copy Copyright 1999 by the MassachusettsInstitute of Technology and Yale University
Volume 3 Number 1
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Journal of Industrial Ecology 111
Address correspondence toGregory A KeoleianCenter for Sustainable SystemsUniversity of MichiganDana Building 430 E UniversityAnn Arbor MI 48109-1115 USAPhone (734) 764-3194Fax (734) 647-5841gregakumichedu
Guidance for ImprovingLife-Cycle Design andManagement of Milk PackagingGregory A KeoleianCenter for Sustainable SystemsUniversity of MichiganAnn Arbor MI USA
David V SpitzleyBattelle Memorial InstituteColumbus OH USA
y
Summary
Life-cycle inventory and cost-analysis tools applied to milkpackaging offer guidelines for achieving better environmen-tal design and management of these systems Life-cyclesolid waste energy and costs were analyzed for seven sys-tems including single-use and refillable glass bottles single-use and refillable high-density polyethylene (HDPE) bottlespaperboard gable-top cartons linear low-density polyeth-ylene (LLDPE) flexible pouches and polycarbonate refill-able bottles on a basis of 1000 gal of milk delivered Inaddition performance requirements were also investigatedthat highlighted potential barriers and trade-offs for envi-ronmentally preferable alternatives Sensitivity analyses in-dicated that material production energy postconsumersolid waste and empty container costs were key param-eters for predicting life-cycle burdens and costs Recenttrends in recycling rates tipping fees and recycled materi-als market value had minimal effect on the results Inven-tory model results for life-cycle solid waste and energyindicated the same rank order as results from previouslypublished life-cycle inventory studies of container systems
Refillable HDPE and polycarbonate and the flexiblepouch were identified as the most environmentally prefer-able with respect to life-cycle energy and solid waste Thegreater market penetration of these containers may be lim-ited by performance issues such as empty container stor-age handling requirements and deposit fees for refillablesand resealability and puncture resistance for the pouch
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Introduction
Packaging is a fundamental element of almostevery product system Although product contain-ment protection aesthetics and information pro-vision are the primary requirements influencingpackaging design packaging has also received sig-nificant environmental scrutiny over the last twodecades In particular postconsumer packagingwaste has been targeted for reduction by manufac-turers consumers and policy makers Postcon-sumer solid waste reduction represents animportant opportunity for environmental im-provement however this metric provides only apartial characterization of the total environmentalburden of the package Life-cycle assessment (USEPA 1995 SETAC 1993) represents a more com-prehensive environmental assessment of a packag-ing system by addressing other environmentalburdens such as energy and raw material consump-tion as well as air and water pollutant emissionsThese burdens are evaluated in the material pro-duction manufacturing use and end-of-life man-agement phases of the packaging life cycle
A wide range of life-cycle assessments(LCAs) of packaging systems have been con-ducted (Dover et al 1993 Kooijman 1993 Kutaet al 1995 Midwest Research Institute 1976Deloitte and Touche 1991 Franklin Associates1991 Lundholm and Sundstrom 1985 Boustead1995 Swiss FOEFL 1991 1996) to better under-stand the environmental profile of alternativepackaging systems However full integration ofenvironmental issues into design managementand policy decisions that influence packaginghas been limited in scope In addition to charac-terizing the environmental burdens related topackaging systems improving the sustainabilityof these systems also requires a better under-standing of other key factors affecting their man-agement These factors include a complex set ofeconomic performance and regulatorypolicyrequirements The life-cycle design frameworkprovides a systems-oriented method for analyz-ing these multiple and often conflicting objec-tives (Keoleian et al 1995 Keoleian andMenerey 1993a) This paper evaluates the envi-ronmental cost and performance profiles ofmilk packaging alternatives to develop specificdesign and management guidelines Inventory
and cost models were developed to measure thelife-cycle energy solid waste and costs for sevenalternative milk packaging systems Sensitivityanalyses of key model parameters were con-ducted and inventory model results were com-pared with results from previously publishedstudies In addition performance requirementswere examined and trade-offs among system re-quirements were identified
Methodology
Product System
The methodology for a comparative assess-ment of milk packaging begins with a clear defi-nition of the product system under investigationTo analyze milk container design and manage-ment seven milk containers including single-useand refillable glass bottles single-use and refill-able high-density polyethylene (HDPE) bottlespaperboard gable-top cartons linear low densitypolyethylene (LLDPE) flexible pouches andpolycarbonate bottles were investigated Con-tainer mass and US national average recyclingrates for each container are presented in table 1Sensitivity analyses of key product system pa-rameters including trippage rates containermass landfill tipping fees recycled material mar-ket value and recycle rates were conductedTable 2 provides data on the market value of re-cycled HDPE and glass between 1995 and 1997
This study considered the life-cycle aspects ofmilk packaging for sale to households Packagesused for the delivery of fresh dairy milk were se-lected for study Systems for delivering milk toon-site users such as school lunch programswere not included in this study Additionallythis study did not address impacts associatedwith beverage production and filling Data ontrippage rates for refillable containers variedconsiderably depending on the means of distri-bution and container material Trippage for glassrefillable bottles has been reported to averagebetween 20 and 30 trips (Swope 1995 CalderDairy 1997 Oberwise Dairy 1997) but a milkbottle manufacturer indicated values range fromless than 10 for milk sold by large grocery chainsto 20 to 35 for dairies that own retail stores to 30to 50 for home-delivered milk (Stanpac 1997)
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 113
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
For polycarbonate trippage was reported to av-erage 50 trips (Swope 1995) A dairy in SaratogaSprings New York indicated that polycarbonatebottle trippage was approximately 12 trips forgrocery store retail due in large part to the lackof returns made by customers This dairy how-ever reports that lunch programs yielded atrippage of about 100 trips (Stewartrsquos Dairy1997)
As of 1990 HDPE bottles dominated theUS household milk container market with a68 (volume basis) share whereas paperboard(gable-top) cartons commanded 32 of themarket All other milk containers had a lessthan 1 share (HarborSide Research 1994) In-terestingly the Canadian market is quite differ-
Table 1 Mass and US national recycling rates for container systems (US EPA 1997)
Container Mass a (gcontainer) Recycling Rate ()
1995 1994 1993 1992
One-half-gal (19 L) ContainersGlass bottle
Refillable 9230 c 216 198 199 214Single use 5590 b 216 198 199 214
HDPE bottleRefillable 1340 c 302 293 241 211Single use 452 d 302 293 241 211
LLDPE pouchSingle use 104 b g
Paperboard cartonSingle use 645 d Neg Neg Neg Neg
Polycarbonate bottleRefillable 1219 e g
One-gal (38 L) ContainersGlass bottle
Refillable 14640 c 216 198 199 214HDPE bottle
Refillable 1680 c 302 293 241 211Single use 642 d 302 293 241 211
Paperboard cartonSingle use 1130 d Neg Neg Neg Neg
a Container mass includes caps and labelsb Container mass based on conversation with industry representativec Source (Midwest Research Institute 1976)d Source (Franklin Associates 1991)e Source (Saphire 1994)f The LLDPE pouch is a flexible pouch produced in a form-fill-seal continuous operation The resin used for pouchproduction consists of a mixture of 80 LLDPE with 20 low-density polyethylene (LDPE)g No recycling rate was available for polycarbonate bottles or LLDPE pouches
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ent The flexible pouch claimed a 55 marketshare in 1988 (Erickson 1988) which had in-creased to 83 in 1995 (EPIC 1997) This dis-crepancy along with historical trends makesmany industry analysts believe that there is po-tential for change in the US dairy market(Erickson 1988)
A functional unit of 1000 gal (37854 liters)of delivered milk was used to compare containerson an equivalent use basis This basis was used forall environmental and cost assessments unlessotherwise indicated By contrast the performanceassessment is strictly qualitative in nature
Environmental Assessment
An inventory model was developed to ex-plore the sensitivity of the life-cycle energy andsolid waste burdens to changes in key param-eters The inventory model used 1990 and 1996material production data sets published by asingle source (Ecobalance of Packaging Materi-als Swiss FOEFL 1991 1996) with the excep-tion of polycarbonate which comes fromFranklin (1990) and Boustead (1997) The in-ventory model utilized published data (PPI1995) when appropriate to evaluate the energyrequired for container formation The energyused and solid waste generated by bottle washingfor refillables were determined from MidwestResearch Institute (1976) and compared withrecent data on steam requirements for washingequipment (Dostal amp Lowey ManufacturingCompany 1997) Fuel economy (single-unit die-sel truck) and the solid waste generation factorfor fuel production for the 120-mile transportdistance between the dairy and retail stores wereobtained from Franklin Associates (1992)Transportation energy was modeled assuming alinear relationship between weight and fuel con-sumption more precise modeling was beyondthe scope of this study For example the energyfactor for a single-unit truck is 3136 Btuton-mile (2266 MJ1000 kg-km) and this factor as-sumed that trucks returned empty to theirstarting point For refillable containers thetransportation energy for back hauling emptycontainers was also inventoried In the con-tainer end-of-life stage the energy required forpostconsumer container collection recycling
and disposal were taken from Franklin Associ-ates (1994) The end-of-life solid waste was de-termined based on the container weight andnational average data for the percentage of con-tainers recovered for recycling and the fractionof municipal solid waste incinerated which is16 (US EPA 1996)
Sensitivity analyses were performed to explorethe effects of container weight on life-cycle energyand solid waste and the effects of postconsumerrecycling rates on life-cycle solid waste The envi-ronmental assessment of alternative milk contain-ers presented here includes results frompreviously published life-cycle inventory studies(Midwest Research Institute 1976 Franklin Asso-ciates 1991) These results are compared withmodel results A larger data set for other beveragecontainer systems studied by the authors is re-ported elsewhere (Keoleian et al 1997)
The availability of published US or NorthAmerican material production inventory data iscurrently very limited Consequently this inves-tigation relied heavily on European materialproduction data Production processes are notexpected to differ significantly between Europeand the United States for the materials investi-gated herein Electricity production efficienciesfor Europe and the United States are very com-parable relative to other inventory parameterssuch as air pollutant emission factors hence thisfactor may not strongly affect the representative-ness of the European energy data for US condi-tions For example the electricity productionefficiency for the national grid in the UnitedStates has been reported as 032 (Franklin Asso-ciates 1992) whereas the efficiency for theUnion for the Connection of Production andTransportation of Electricity (UCPTE) wasfound to be 0378 (Swiss FOEFL 1991) Re-gional differences in electricity productionwithin the United States and Europe howeverare much greater than this difference and couldbe significant An analysis of the electricity sup-ply system in the United States indicated thatthe electricity production efficiency varies be-tween 22 and 47 across the ten regionalgrids as defined by the North American ElectricReliability Council (Boustead and Yaros 1994)The influence of the electricity production effi-ciency is minimal because electricity accounts
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 115
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
for between 1 and 28 of the total materialproduction energies for glass plastic resins andpaperboard
Environmental releases could however dif-fer significantly due in part to differences in en-vironmental regulations controlling thesematerial industries In general airborne emis-sions and water effluents data show significantvariability For example a comparison of mate-rial production databases of two major life-cyclepractitioners indicated that the air and wateremissions data varied by as much as 187(Keoleian and McDaniel 1997)1 For this reasonairborne and waterborne emissions data werenot incorporated in this environmental analysis
Cost Assessment
The life-cycle costs analyzed for each con-tainer system include empty container costs fill-ing costs transportation costs and end-of-lifemanagement costs Empty container costs wereevaluated based on the price paid by fillers forenough containers to deliver 1000 gal of milkFilling costs accounted for amortized equipmentcosts only labor and utility costs were not evalu-ated Labor and utility cost data were not avail-able because they were regarded as proprietaryby the dairy industry The cost of transportationfuel was estimated for distributing full containersto retail locations and for the return of emptytrucks back to their starting point Back hauls ofempty containers for refillables were also in-cluded in the cost of transportation to retailModel parameters used for the transportationcost analysis are reported elsewhere (Keoleian etal 1997)
Finally the end-of-life management costswere determined for each container End-of-lifemanagement costs included collection materialor energy recovery costs and landfill disposalcosts Material recovery costs assumed curbsidecollection and accounted for both the materialprocessing costs at a recycling facility and themarket value of recovered materials Waste-to-energy recovery costs were also estimated by ac-counting for the energy embodied in eachcombustible container The cost of disposing ofthe remaining postconsumer wastes not recycledor incinerated were then calculated using an av-
erage tipping fee for sanitary landfill dispositionof municipal solid waste (MSW) in the US re-ported by the National Solid Waste ManagementAssociation of $3025ton (June 1995) Sensitiv-ity analyses were conducted to investigate the ef-fects of volatility in recycled material marketsand solid waste tipping fees on life-cycle resultsRecent national average tipping fees from 1993to 1996 were obtained from BioCycle and the re-gional variation in tipping fees for 1996 were alsoexamined Secondary material prices for glass andHDPE between January 1995 and October 1997were obtained from Recycling Times
The total life-cycle cost is the sum of emptycontainer cost filling equipment cost cost oftransportation to retail and end-of-life manage-ment costs Milk retail prices were not used toestimate relative costs of alternative milk pack-aging The cost for packaging is not always accu-rately reflected in the retail price because milkproducts are often merchandised as loss leaders2
with a very low and variable profit margin
Performance Assessment
Performance requirements define the func-tional attributes of a product system A literaturesurvey revealed that six functional attributes sig-nificantly influence milk package design and se-lection These performance requirements arecontainer clarity burstshatter resistance ease ofopening weight resealability and handling ofempty refillable containers (Dairy Industries In-ternational 1994 Dexheimer 1993 Sfiligoj1994 Urbanski 1991) These attributes are rel-evant to many stakeholders of the milk packag-ing life cycle including package designersdairies distributor s retailers and consumersSeveral potentially important criteria were notevaluated such as barrier properties taste char-acteristics and aesthetics (Urbanski 1991Sfiligoj 1994 Saphire 1994)
After the literature survey was completedeach container was subjectively evaluated basedon the authorsrsquo judgment for the six perfor-mance measures and ranked as follows good (+)neutral (0) or poor (ndash) In this analysis each ofthe six criteria was weighted equally to deter-mine an overall performance score Stakeholderanalysis including focused market research
116 Jour nal of Industrial Ecology
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would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
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is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
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Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
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and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
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most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
112 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Introduction
Packaging is a fundamental element of almostevery product system Although product contain-ment protection aesthetics and information pro-vision are the primary requirements influencingpackaging design packaging has also received sig-nificant environmental scrutiny over the last twodecades In particular postconsumer packagingwaste has been targeted for reduction by manufac-turers consumers and policy makers Postcon-sumer solid waste reduction represents animportant opportunity for environmental im-provement however this metric provides only apartial characterization of the total environmentalburden of the package Life-cycle assessment (USEPA 1995 SETAC 1993) represents a more com-prehensive environmental assessment of a packag-ing system by addressing other environmentalburdens such as energy and raw material consump-tion as well as air and water pollutant emissionsThese burdens are evaluated in the material pro-duction manufacturing use and end-of-life man-agement phases of the packaging life cycle
A wide range of life-cycle assessments(LCAs) of packaging systems have been con-ducted (Dover et al 1993 Kooijman 1993 Kutaet al 1995 Midwest Research Institute 1976Deloitte and Touche 1991 Franklin Associates1991 Lundholm and Sundstrom 1985 Boustead1995 Swiss FOEFL 1991 1996) to better under-stand the environmental profile of alternativepackaging systems However full integration ofenvironmental issues into design managementand policy decisions that influence packaginghas been limited in scope In addition to charac-terizing the environmental burdens related topackaging systems improving the sustainabilityof these systems also requires a better under-standing of other key factors affecting their man-agement These factors include a complex set ofeconomic performance and regulatorypolicyrequirements The life-cycle design frameworkprovides a systems-oriented method for analyz-ing these multiple and often conflicting objec-tives (Keoleian et al 1995 Keoleian andMenerey 1993a) This paper evaluates the envi-ronmental cost and performance profiles ofmilk packaging alternatives to develop specificdesign and management guidelines Inventory
and cost models were developed to measure thelife-cycle energy solid waste and costs for sevenalternative milk packaging systems Sensitivityanalyses of key model parameters were con-ducted and inventory model results were com-pared with results from previously publishedstudies In addition performance requirementswere examined and trade-offs among system re-quirements were identified
Methodology
Product System
The methodology for a comparative assess-ment of milk packaging begins with a clear defi-nition of the product system under investigationTo analyze milk container design and manage-ment seven milk containers including single-useand refillable glass bottles single-use and refill-able high-density polyethylene (HDPE) bottlespaperboard gable-top cartons linear low densitypolyethylene (LLDPE) flexible pouches andpolycarbonate bottles were investigated Con-tainer mass and US national average recyclingrates for each container are presented in table 1Sensitivity analyses of key product system pa-rameters including trippage rates containermass landfill tipping fees recycled material mar-ket value and recycle rates were conductedTable 2 provides data on the market value of re-cycled HDPE and glass between 1995 and 1997
This study considered the life-cycle aspects ofmilk packaging for sale to households Packagesused for the delivery of fresh dairy milk were se-lected for study Systems for delivering milk toon-site users such as school lunch programswere not included in this study Additionallythis study did not address impacts associatedwith beverage production and filling Data ontrippage rates for refillable containers variedconsiderably depending on the means of distri-bution and container material Trippage for glassrefillable bottles has been reported to averagebetween 20 and 30 trips (Swope 1995 CalderDairy 1997 Oberwise Dairy 1997) but a milkbottle manufacturer indicated values range fromless than 10 for milk sold by large grocery chainsto 20 to 35 for dairies that own retail stores to 30to 50 for home-delivered milk (Stanpac 1997)
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 113
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
For polycarbonate trippage was reported to av-erage 50 trips (Swope 1995) A dairy in SaratogaSprings New York indicated that polycarbonatebottle trippage was approximately 12 trips forgrocery store retail due in large part to the lackof returns made by customers This dairy how-ever reports that lunch programs yielded atrippage of about 100 trips (Stewartrsquos Dairy1997)
As of 1990 HDPE bottles dominated theUS household milk container market with a68 (volume basis) share whereas paperboard(gable-top) cartons commanded 32 of themarket All other milk containers had a lessthan 1 share (HarborSide Research 1994) In-terestingly the Canadian market is quite differ-
Table 1 Mass and US national recycling rates for container systems (US EPA 1997)
Container Mass a (gcontainer) Recycling Rate ()
1995 1994 1993 1992
One-half-gal (19 L) ContainersGlass bottle
Refillable 9230 c 216 198 199 214Single use 5590 b 216 198 199 214
HDPE bottleRefillable 1340 c 302 293 241 211Single use 452 d 302 293 241 211
LLDPE pouchSingle use 104 b g
Paperboard cartonSingle use 645 d Neg Neg Neg Neg
Polycarbonate bottleRefillable 1219 e g
One-gal (38 L) ContainersGlass bottle
Refillable 14640 c 216 198 199 214HDPE bottle
Refillable 1680 c 302 293 241 211Single use 642 d 302 293 241 211
Paperboard cartonSingle use 1130 d Neg Neg Neg Neg
a Container mass includes caps and labelsb Container mass based on conversation with industry representativec Source (Midwest Research Institute 1976)d Source (Franklin Associates 1991)e Source (Saphire 1994)f The LLDPE pouch is a flexible pouch produced in a form-fill-seal continuous operation The resin used for pouchproduction consists of a mixture of 80 LLDPE with 20 low-density polyethylene (LDPE)g No recycling rate was available for polycarbonate bottles or LLDPE pouches
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ent The flexible pouch claimed a 55 marketshare in 1988 (Erickson 1988) which had in-creased to 83 in 1995 (EPIC 1997) This dis-crepancy along with historical trends makesmany industry analysts believe that there is po-tential for change in the US dairy market(Erickson 1988)
A functional unit of 1000 gal (37854 liters)of delivered milk was used to compare containerson an equivalent use basis This basis was used forall environmental and cost assessments unlessotherwise indicated By contrast the performanceassessment is strictly qualitative in nature
Environmental Assessment
An inventory model was developed to ex-plore the sensitivity of the life-cycle energy andsolid waste burdens to changes in key param-eters The inventory model used 1990 and 1996material production data sets published by asingle source (Ecobalance of Packaging Materi-als Swiss FOEFL 1991 1996) with the excep-tion of polycarbonate which comes fromFranklin (1990) and Boustead (1997) The in-ventory model utilized published data (PPI1995) when appropriate to evaluate the energyrequired for container formation The energyused and solid waste generated by bottle washingfor refillables were determined from MidwestResearch Institute (1976) and compared withrecent data on steam requirements for washingequipment (Dostal amp Lowey ManufacturingCompany 1997) Fuel economy (single-unit die-sel truck) and the solid waste generation factorfor fuel production for the 120-mile transportdistance between the dairy and retail stores wereobtained from Franklin Associates (1992)Transportation energy was modeled assuming alinear relationship between weight and fuel con-sumption more precise modeling was beyondthe scope of this study For example the energyfactor for a single-unit truck is 3136 Btuton-mile (2266 MJ1000 kg-km) and this factor as-sumed that trucks returned empty to theirstarting point For refillable containers thetransportation energy for back hauling emptycontainers was also inventoried In the con-tainer end-of-life stage the energy required forpostconsumer container collection recycling
and disposal were taken from Franklin Associ-ates (1994) The end-of-life solid waste was de-termined based on the container weight andnational average data for the percentage of con-tainers recovered for recycling and the fractionof municipal solid waste incinerated which is16 (US EPA 1996)
Sensitivity analyses were performed to explorethe effects of container weight on life-cycle energyand solid waste and the effects of postconsumerrecycling rates on life-cycle solid waste The envi-ronmental assessment of alternative milk contain-ers presented here includes results frompreviously published life-cycle inventory studies(Midwest Research Institute 1976 Franklin Asso-ciates 1991) These results are compared withmodel results A larger data set for other beveragecontainer systems studied by the authors is re-ported elsewhere (Keoleian et al 1997)
The availability of published US or NorthAmerican material production inventory data iscurrently very limited Consequently this inves-tigation relied heavily on European materialproduction data Production processes are notexpected to differ significantly between Europeand the United States for the materials investi-gated herein Electricity production efficienciesfor Europe and the United States are very com-parable relative to other inventory parameterssuch as air pollutant emission factors hence thisfactor may not strongly affect the representative-ness of the European energy data for US condi-tions For example the electricity productionefficiency for the national grid in the UnitedStates has been reported as 032 (Franklin Asso-ciates 1992) whereas the efficiency for theUnion for the Connection of Production andTransportation of Electricity (UCPTE) wasfound to be 0378 (Swiss FOEFL 1991) Re-gional differences in electricity productionwithin the United States and Europe howeverare much greater than this difference and couldbe significant An analysis of the electricity sup-ply system in the United States indicated thatthe electricity production efficiency varies be-tween 22 and 47 across the ten regionalgrids as defined by the North American ElectricReliability Council (Boustead and Yaros 1994)The influence of the electricity production effi-ciency is minimal because electricity accounts
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 115
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
for between 1 and 28 of the total materialproduction energies for glass plastic resins andpaperboard
Environmental releases could however dif-fer significantly due in part to differences in en-vironmental regulations controlling thesematerial industries In general airborne emis-sions and water effluents data show significantvariability For example a comparison of mate-rial production databases of two major life-cyclepractitioners indicated that the air and wateremissions data varied by as much as 187(Keoleian and McDaniel 1997)1 For this reasonairborne and waterborne emissions data werenot incorporated in this environmental analysis
Cost Assessment
The life-cycle costs analyzed for each con-tainer system include empty container costs fill-ing costs transportation costs and end-of-lifemanagement costs Empty container costs wereevaluated based on the price paid by fillers forenough containers to deliver 1000 gal of milkFilling costs accounted for amortized equipmentcosts only labor and utility costs were not evalu-ated Labor and utility cost data were not avail-able because they were regarded as proprietaryby the dairy industry The cost of transportationfuel was estimated for distributing full containersto retail locations and for the return of emptytrucks back to their starting point Back hauls ofempty containers for refillables were also in-cluded in the cost of transportation to retailModel parameters used for the transportationcost analysis are reported elsewhere (Keoleian etal 1997)
Finally the end-of-life management costswere determined for each container End-of-lifemanagement costs included collection materialor energy recovery costs and landfill disposalcosts Material recovery costs assumed curbsidecollection and accounted for both the materialprocessing costs at a recycling facility and themarket value of recovered materials Waste-to-energy recovery costs were also estimated by ac-counting for the energy embodied in eachcombustible container The cost of disposing ofthe remaining postconsumer wastes not recycledor incinerated were then calculated using an av-
erage tipping fee for sanitary landfill dispositionof municipal solid waste (MSW) in the US re-ported by the National Solid Waste ManagementAssociation of $3025ton (June 1995) Sensitiv-ity analyses were conducted to investigate the ef-fects of volatility in recycled material marketsand solid waste tipping fees on life-cycle resultsRecent national average tipping fees from 1993to 1996 were obtained from BioCycle and the re-gional variation in tipping fees for 1996 were alsoexamined Secondary material prices for glass andHDPE between January 1995 and October 1997were obtained from Recycling Times
The total life-cycle cost is the sum of emptycontainer cost filling equipment cost cost oftransportation to retail and end-of-life manage-ment costs Milk retail prices were not used toestimate relative costs of alternative milk pack-aging The cost for packaging is not always accu-rately reflected in the retail price because milkproducts are often merchandised as loss leaders2
with a very low and variable profit margin
Performance Assessment
Performance requirements define the func-tional attributes of a product system A literaturesurvey revealed that six functional attributes sig-nificantly influence milk package design and se-lection These performance requirements arecontainer clarity burstshatter resistance ease ofopening weight resealability and handling ofempty refillable containers (Dairy Industries In-ternational 1994 Dexheimer 1993 Sfiligoj1994 Urbanski 1991) These attributes are rel-evant to many stakeholders of the milk packag-ing life cycle including package designersdairies distributor s retailers and consumersSeveral potentially important criteria were notevaluated such as barrier properties taste char-acteristics and aesthetics (Urbanski 1991Sfiligoj 1994 Saphire 1994)
After the literature survey was completedeach container was subjectively evaluated basedon the authorsrsquo judgment for the six perfor-mance measures and ranked as follows good (+)neutral (0) or poor (ndash) In this analysis each ofthe six criteria was weighted equally to deter-mine an overall performance score Stakeholderanalysis including focused market research
116 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 113
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
For polycarbonate trippage was reported to av-erage 50 trips (Swope 1995) A dairy in SaratogaSprings New York indicated that polycarbonatebottle trippage was approximately 12 trips forgrocery store retail due in large part to the lackof returns made by customers This dairy how-ever reports that lunch programs yielded atrippage of about 100 trips (Stewartrsquos Dairy1997)
As of 1990 HDPE bottles dominated theUS household milk container market with a68 (volume basis) share whereas paperboard(gable-top) cartons commanded 32 of themarket All other milk containers had a lessthan 1 share (HarborSide Research 1994) In-terestingly the Canadian market is quite differ-
Table 1 Mass and US national recycling rates for container systems (US EPA 1997)
Container Mass a (gcontainer) Recycling Rate ()
1995 1994 1993 1992
One-half-gal (19 L) ContainersGlass bottle
Refillable 9230 c 216 198 199 214Single use 5590 b 216 198 199 214
HDPE bottleRefillable 1340 c 302 293 241 211Single use 452 d 302 293 241 211
LLDPE pouchSingle use 104 b g
Paperboard cartonSingle use 645 d Neg Neg Neg Neg
Polycarbonate bottleRefillable 1219 e g
One-gal (38 L) ContainersGlass bottle
Refillable 14640 c 216 198 199 214HDPE bottle
Refillable 1680 c 302 293 241 211Single use 642 d 302 293 241 211
Paperboard cartonSingle use 1130 d Neg Neg Neg Neg
a Container mass includes caps and labelsb Container mass based on conversation with industry representativec Source (Midwest Research Institute 1976)d Source (Franklin Associates 1991)e Source (Saphire 1994)f The LLDPE pouch is a flexible pouch produced in a form-fill-seal continuous operation The resin used for pouchproduction consists of a mixture of 80 LLDPE with 20 low-density polyethylene (LDPE)g No recycling rate was available for polycarbonate bottles or LLDPE pouches
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ent The flexible pouch claimed a 55 marketshare in 1988 (Erickson 1988) which had in-creased to 83 in 1995 (EPIC 1997) This dis-crepancy along with historical trends makesmany industry analysts believe that there is po-tential for change in the US dairy market(Erickson 1988)
A functional unit of 1000 gal (37854 liters)of delivered milk was used to compare containerson an equivalent use basis This basis was used forall environmental and cost assessments unlessotherwise indicated By contrast the performanceassessment is strictly qualitative in nature
Environmental Assessment
An inventory model was developed to ex-plore the sensitivity of the life-cycle energy andsolid waste burdens to changes in key param-eters The inventory model used 1990 and 1996material production data sets published by asingle source (Ecobalance of Packaging Materi-als Swiss FOEFL 1991 1996) with the excep-tion of polycarbonate which comes fromFranklin (1990) and Boustead (1997) The in-ventory model utilized published data (PPI1995) when appropriate to evaluate the energyrequired for container formation The energyused and solid waste generated by bottle washingfor refillables were determined from MidwestResearch Institute (1976) and compared withrecent data on steam requirements for washingequipment (Dostal amp Lowey ManufacturingCompany 1997) Fuel economy (single-unit die-sel truck) and the solid waste generation factorfor fuel production for the 120-mile transportdistance between the dairy and retail stores wereobtained from Franklin Associates (1992)Transportation energy was modeled assuming alinear relationship between weight and fuel con-sumption more precise modeling was beyondthe scope of this study For example the energyfactor for a single-unit truck is 3136 Btuton-mile (2266 MJ1000 kg-km) and this factor as-sumed that trucks returned empty to theirstarting point For refillable containers thetransportation energy for back hauling emptycontainers was also inventoried In the con-tainer end-of-life stage the energy required forpostconsumer container collection recycling
and disposal were taken from Franklin Associ-ates (1994) The end-of-life solid waste was de-termined based on the container weight andnational average data for the percentage of con-tainers recovered for recycling and the fractionof municipal solid waste incinerated which is16 (US EPA 1996)
Sensitivity analyses were performed to explorethe effects of container weight on life-cycle energyand solid waste and the effects of postconsumerrecycling rates on life-cycle solid waste The envi-ronmental assessment of alternative milk contain-ers presented here includes results frompreviously published life-cycle inventory studies(Midwest Research Institute 1976 Franklin Asso-ciates 1991) These results are compared withmodel results A larger data set for other beveragecontainer systems studied by the authors is re-ported elsewhere (Keoleian et al 1997)
The availability of published US or NorthAmerican material production inventory data iscurrently very limited Consequently this inves-tigation relied heavily on European materialproduction data Production processes are notexpected to differ significantly between Europeand the United States for the materials investi-gated herein Electricity production efficienciesfor Europe and the United States are very com-parable relative to other inventory parameterssuch as air pollutant emission factors hence thisfactor may not strongly affect the representative-ness of the European energy data for US condi-tions For example the electricity productionefficiency for the national grid in the UnitedStates has been reported as 032 (Franklin Asso-ciates 1992) whereas the efficiency for theUnion for the Connection of Production andTransportation of Electricity (UCPTE) wasfound to be 0378 (Swiss FOEFL 1991) Re-gional differences in electricity productionwithin the United States and Europe howeverare much greater than this difference and couldbe significant An analysis of the electricity sup-ply system in the United States indicated thatthe electricity production efficiency varies be-tween 22 and 47 across the ten regionalgrids as defined by the North American ElectricReliability Council (Boustead and Yaros 1994)The influence of the electricity production effi-ciency is minimal because electricity accounts
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 115
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
for between 1 and 28 of the total materialproduction energies for glass plastic resins andpaperboard
Environmental releases could however dif-fer significantly due in part to differences in en-vironmental regulations controlling thesematerial industries In general airborne emis-sions and water effluents data show significantvariability For example a comparison of mate-rial production databases of two major life-cyclepractitioners indicated that the air and wateremissions data varied by as much as 187(Keoleian and McDaniel 1997)1 For this reasonairborne and waterborne emissions data werenot incorporated in this environmental analysis
Cost Assessment
The life-cycle costs analyzed for each con-tainer system include empty container costs fill-ing costs transportation costs and end-of-lifemanagement costs Empty container costs wereevaluated based on the price paid by fillers forenough containers to deliver 1000 gal of milkFilling costs accounted for amortized equipmentcosts only labor and utility costs were not evalu-ated Labor and utility cost data were not avail-able because they were regarded as proprietaryby the dairy industry The cost of transportationfuel was estimated for distributing full containersto retail locations and for the return of emptytrucks back to their starting point Back hauls ofempty containers for refillables were also in-cluded in the cost of transportation to retailModel parameters used for the transportationcost analysis are reported elsewhere (Keoleian etal 1997)
Finally the end-of-life management costswere determined for each container End-of-lifemanagement costs included collection materialor energy recovery costs and landfill disposalcosts Material recovery costs assumed curbsidecollection and accounted for both the materialprocessing costs at a recycling facility and themarket value of recovered materials Waste-to-energy recovery costs were also estimated by ac-counting for the energy embodied in eachcombustible container The cost of disposing ofthe remaining postconsumer wastes not recycledor incinerated were then calculated using an av-
erage tipping fee for sanitary landfill dispositionof municipal solid waste (MSW) in the US re-ported by the National Solid Waste ManagementAssociation of $3025ton (June 1995) Sensitiv-ity analyses were conducted to investigate the ef-fects of volatility in recycled material marketsand solid waste tipping fees on life-cycle resultsRecent national average tipping fees from 1993to 1996 were obtained from BioCycle and the re-gional variation in tipping fees for 1996 were alsoexamined Secondary material prices for glass andHDPE between January 1995 and October 1997were obtained from Recycling Times
The total life-cycle cost is the sum of emptycontainer cost filling equipment cost cost oftransportation to retail and end-of-life manage-ment costs Milk retail prices were not used toestimate relative costs of alternative milk pack-aging The cost for packaging is not always accu-rately reflected in the retail price because milkproducts are often merchandised as loss leaders2
with a very low and variable profit margin
Performance Assessment
Performance requirements define the func-tional attributes of a product system A literaturesurvey revealed that six functional attributes sig-nificantly influence milk package design and se-lection These performance requirements arecontainer clarity burstshatter resistance ease ofopening weight resealability and handling ofempty refillable containers (Dairy Industries In-ternational 1994 Dexheimer 1993 Sfiligoj1994 Urbanski 1991) These attributes are rel-evant to many stakeholders of the milk packag-ing life cycle including package designersdairies distributor s retailers and consumersSeveral potentially important criteria were notevaluated such as barrier properties taste char-acteristics and aesthetics (Urbanski 1991Sfiligoj 1994 Saphire 1994)
After the literature survey was completedeach container was subjectively evaluated basedon the authorsrsquo judgment for the six perfor-mance measures and ranked as follows good (+)neutral (0) or poor (ndash) In this analysis each ofthe six criteria was weighted equally to deter-mine an overall performance score Stakeholderanalysis including focused market research
116 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
114 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ent The flexible pouch claimed a 55 marketshare in 1988 (Erickson 1988) which had in-creased to 83 in 1995 (EPIC 1997) This dis-crepancy along with historical trends makesmany industry analysts believe that there is po-tential for change in the US dairy market(Erickson 1988)
A functional unit of 1000 gal (37854 liters)of delivered milk was used to compare containerson an equivalent use basis This basis was used forall environmental and cost assessments unlessotherwise indicated By contrast the performanceassessment is strictly qualitative in nature
Environmental Assessment
An inventory model was developed to ex-plore the sensitivity of the life-cycle energy andsolid waste burdens to changes in key param-eters The inventory model used 1990 and 1996material production data sets published by asingle source (Ecobalance of Packaging Materi-als Swiss FOEFL 1991 1996) with the excep-tion of polycarbonate which comes fromFranklin (1990) and Boustead (1997) The in-ventory model utilized published data (PPI1995) when appropriate to evaluate the energyrequired for container formation The energyused and solid waste generated by bottle washingfor refillables were determined from MidwestResearch Institute (1976) and compared withrecent data on steam requirements for washingequipment (Dostal amp Lowey ManufacturingCompany 1997) Fuel economy (single-unit die-sel truck) and the solid waste generation factorfor fuel production for the 120-mile transportdistance between the dairy and retail stores wereobtained from Franklin Associates (1992)Transportation energy was modeled assuming alinear relationship between weight and fuel con-sumption more precise modeling was beyondthe scope of this study For example the energyfactor for a single-unit truck is 3136 Btuton-mile (2266 MJ1000 kg-km) and this factor as-sumed that trucks returned empty to theirstarting point For refillable containers thetransportation energy for back hauling emptycontainers was also inventoried In the con-tainer end-of-life stage the energy required forpostconsumer container collection recycling
and disposal were taken from Franklin Associ-ates (1994) The end-of-life solid waste was de-termined based on the container weight andnational average data for the percentage of con-tainers recovered for recycling and the fractionof municipal solid waste incinerated which is16 (US EPA 1996)
Sensitivity analyses were performed to explorethe effects of container weight on life-cycle energyand solid waste and the effects of postconsumerrecycling rates on life-cycle solid waste The envi-ronmental assessment of alternative milk contain-ers presented here includes results frompreviously published life-cycle inventory studies(Midwest Research Institute 1976 Franklin Asso-ciates 1991) These results are compared withmodel results A larger data set for other beveragecontainer systems studied by the authors is re-ported elsewhere (Keoleian et al 1997)
The availability of published US or NorthAmerican material production inventory data iscurrently very limited Consequently this inves-tigation relied heavily on European materialproduction data Production processes are notexpected to differ significantly between Europeand the United States for the materials investi-gated herein Electricity production efficienciesfor Europe and the United States are very com-parable relative to other inventory parameterssuch as air pollutant emission factors hence thisfactor may not strongly affect the representative-ness of the European energy data for US condi-tions For example the electricity productionefficiency for the national grid in the UnitedStates has been reported as 032 (Franklin Asso-ciates 1992) whereas the efficiency for theUnion for the Connection of Production andTransportation of Electricity (UCPTE) wasfound to be 0378 (Swiss FOEFL 1991) Re-gional differences in electricity productionwithin the United States and Europe howeverare much greater than this difference and couldbe significant An analysis of the electricity sup-ply system in the United States indicated thatthe electricity production efficiency varies be-tween 22 and 47 across the ten regionalgrids as defined by the North American ElectricReliability Council (Boustead and Yaros 1994)The influence of the electricity production effi-ciency is minimal because electricity accounts
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 115
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
for between 1 and 28 of the total materialproduction energies for glass plastic resins andpaperboard
Environmental releases could however dif-fer significantly due in part to differences in en-vironmental regulations controlling thesematerial industries In general airborne emis-sions and water effluents data show significantvariability For example a comparison of mate-rial production databases of two major life-cyclepractitioners indicated that the air and wateremissions data varied by as much as 187(Keoleian and McDaniel 1997)1 For this reasonairborne and waterborne emissions data werenot incorporated in this environmental analysis
Cost Assessment
The life-cycle costs analyzed for each con-tainer system include empty container costs fill-ing costs transportation costs and end-of-lifemanagement costs Empty container costs wereevaluated based on the price paid by fillers forenough containers to deliver 1000 gal of milkFilling costs accounted for amortized equipmentcosts only labor and utility costs were not evalu-ated Labor and utility cost data were not avail-able because they were regarded as proprietaryby the dairy industry The cost of transportationfuel was estimated for distributing full containersto retail locations and for the return of emptytrucks back to their starting point Back hauls ofempty containers for refillables were also in-cluded in the cost of transportation to retailModel parameters used for the transportationcost analysis are reported elsewhere (Keoleian etal 1997)
Finally the end-of-life management costswere determined for each container End-of-lifemanagement costs included collection materialor energy recovery costs and landfill disposalcosts Material recovery costs assumed curbsidecollection and accounted for both the materialprocessing costs at a recycling facility and themarket value of recovered materials Waste-to-energy recovery costs were also estimated by ac-counting for the energy embodied in eachcombustible container The cost of disposing ofthe remaining postconsumer wastes not recycledor incinerated were then calculated using an av-
erage tipping fee for sanitary landfill dispositionof municipal solid waste (MSW) in the US re-ported by the National Solid Waste ManagementAssociation of $3025ton (June 1995) Sensitiv-ity analyses were conducted to investigate the ef-fects of volatility in recycled material marketsand solid waste tipping fees on life-cycle resultsRecent national average tipping fees from 1993to 1996 were obtained from BioCycle and the re-gional variation in tipping fees for 1996 were alsoexamined Secondary material prices for glass andHDPE between January 1995 and October 1997were obtained from Recycling Times
The total life-cycle cost is the sum of emptycontainer cost filling equipment cost cost oftransportation to retail and end-of-life manage-ment costs Milk retail prices were not used toestimate relative costs of alternative milk pack-aging The cost for packaging is not always accu-rately reflected in the retail price because milkproducts are often merchandised as loss leaders2
with a very low and variable profit margin
Performance Assessment
Performance requirements define the func-tional attributes of a product system A literaturesurvey revealed that six functional attributes sig-nificantly influence milk package design and se-lection These performance requirements arecontainer clarity burstshatter resistance ease ofopening weight resealability and handling ofempty refillable containers (Dairy Industries In-ternational 1994 Dexheimer 1993 Sfiligoj1994 Urbanski 1991) These attributes are rel-evant to many stakeholders of the milk packag-ing life cycle including package designersdairies distributor s retailers and consumersSeveral potentially important criteria were notevaluated such as barrier properties taste char-acteristics and aesthetics (Urbanski 1991Sfiligoj 1994 Saphire 1994)
After the literature survey was completedeach container was subjectively evaluated basedon the authorsrsquo judgment for the six perfor-mance measures and ranked as follows good (+)neutral (0) or poor (ndash) In this analysis each ofthe six criteria was weighted equally to deter-mine an overall performance score Stakeholderanalysis including focused market research
116 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 115
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
for between 1 and 28 of the total materialproduction energies for glass plastic resins andpaperboard
Environmental releases could however dif-fer significantly due in part to differences in en-vironmental regulations controlling thesematerial industries In general airborne emis-sions and water effluents data show significantvariability For example a comparison of mate-rial production databases of two major life-cyclepractitioners indicated that the air and wateremissions data varied by as much as 187(Keoleian and McDaniel 1997)1 For this reasonairborne and waterborne emissions data werenot incorporated in this environmental analysis
Cost Assessment
The life-cycle costs analyzed for each con-tainer system include empty container costs fill-ing costs transportation costs and end-of-lifemanagement costs Empty container costs wereevaluated based on the price paid by fillers forenough containers to deliver 1000 gal of milkFilling costs accounted for amortized equipmentcosts only labor and utility costs were not evalu-ated Labor and utility cost data were not avail-able because they were regarded as proprietaryby the dairy industry The cost of transportationfuel was estimated for distributing full containersto retail locations and for the return of emptytrucks back to their starting point Back hauls ofempty containers for refillables were also in-cluded in the cost of transportation to retailModel parameters used for the transportationcost analysis are reported elsewhere (Keoleian etal 1997)
Finally the end-of-life management costswere determined for each container End-of-lifemanagement costs included collection materialor energy recovery costs and landfill disposalcosts Material recovery costs assumed curbsidecollection and accounted for both the materialprocessing costs at a recycling facility and themarket value of recovered materials Waste-to-energy recovery costs were also estimated by ac-counting for the energy embodied in eachcombustible container The cost of disposing ofthe remaining postconsumer wastes not recycledor incinerated were then calculated using an av-
erage tipping fee for sanitary landfill dispositionof municipal solid waste (MSW) in the US re-ported by the National Solid Waste ManagementAssociation of $3025ton (June 1995) Sensitiv-ity analyses were conducted to investigate the ef-fects of volatility in recycled material marketsand solid waste tipping fees on life-cycle resultsRecent national average tipping fees from 1993to 1996 were obtained from BioCycle and the re-gional variation in tipping fees for 1996 were alsoexamined Secondary material prices for glass andHDPE between January 1995 and October 1997were obtained from Recycling Times
The total life-cycle cost is the sum of emptycontainer cost filling equipment cost cost oftransportation to retail and end-of-life manage-ment costs Milk retail prices were not used toestimate relative costs of alternative milk pack-aging The cost for packaging is not always accu-rately reflected in the retail price because milkproducts are often merchandised as loss leaders2
with a very low and variable profit margin
Performance Assessment
Performance requirements define the func-tional attributes of a product system A literaturesurvey revealed that six functional attributes sig-nificantly influence milk package design and se-lection These performance requirements arecontainer clarity burstshatter resistance ease ofopening weight resealability and handling ofempty refillable containers (Dairy Industries In-ternational 1994 Dexheimer 1993 Sfiligoj1994 Urbanski 1991) These attributes are rel-evant to many stakeholders of the milk packag-ing life cycle including package designersdairies distributor s retailers and consumersSeveral potentially important criteria were notevaluated such as barrier properties taste char-acteristics and aesthetics (Urbanski 1991Sfiligoj 1994 Saphire 1994)
After the literature survey was completedeach container was subjectively evaluated basedon the authorsrsquo judgment for the six perfor-mance measures and ranked as follows good (+)neutral (0) or poor (ndash) In this analysis each ofthe six criteria was weighted equally to deter-mine an overall performance score Stakeholderanalysis including focused market research
116 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
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Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
116 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
would establish a more concrete valuation sys-tem and ranking of performance criteria
Results and Discussion
This section presents the environmentalcost and performance characteristics of theseven milk packaging systems investigated Inreviewing these results trade-offs among the al-ternatives begin to emerge and provide some in-sight into the relative success of these packagingsystems in the market Guidelines are also for-mulated based on the environmental and costassessments to enhance milk packaging designand management decisions
Environmental Assessment
Energy ConsumptionTable 3 presents the total life-cycle energy
consumption for each container based on previ-ous studies and the inventory model using 1990and 1996 (1997 for polycarbonate) material pro-duction data sets Model results using the mostrecent material production data indicate the en-ergy use for refillable containers per 1000 gal ofmilk delivered ranged from 670 MJ for 50-trip 1-gal refillable HDPE bottles to 7200 MJ for a 5-trip 05-gal refillable polycarbonate bottleSingle-use containers per 1000 gal of milk deliv-ered consumed between 2060 MJ for a 05-galflexible pouch and 15300 MJ for a 05-gal glassbottle Refill rates have a dramatic effect on thetotal life-cycle energy consumption of milk con-tainers An individual refillable container is gen-erally more material-intensive relative to asingle-use container of the same design and ma-terial type As container reuse rate increasescontainer production energy becomes less sig-nificant on a unit volume delivered basis Thetotal life-cycle energy approaches the sum of thewashing filling and transport energies in thelimit as the refill rate increases
The inventory model using 1990 and 1996material production data sets corroborated resultsfrom previous studies The rank order of containersystems for life-cycle solid waste and energy wasconsistent among studies In general more recentinventory data sources (1990 and 1996) indicateda lower material production energy that accounts
for the lower total life-cycle energy computedfrom the model compared to previous studiesReasons for these differences may include im-provements in process efficiency energy supplyefficiencies and LCA methods Model resultsbased on the 1990 inventory data set did not dif-fer significantly from the 1996 model case
As is apparent from table 3 material produc-tion energy constitutes the majority of manycontainersrsquo life-cycle energy inputs On averagematerial production consumes 93 89 and90 of total life-cycle energy for single-use milkcontainers for the previously published studiesfor the model results based on the 1990 data setand for the model results based on the 1996 dataset respectively For the high trippage refillablecontainers based on model results with the 1996data set this percentage is only 36 which is ex-pected due to the increased importance of wash-ing and transportation at higher refill rates
Model predictions for the effect of containerweight reduction on the life-cycle energy areshown in table 4 In general table 4 shows a strongcorrelation between weight reduction and life-cycle energy reduction Some beverage containerpackaging has undergone significant weight reduc-tions (Porter 1993) Making containers lighter islimited however because all containers mustmeet minimum strength requirements particu-larly refillable containers No weight reduction forglass refillable bottles was found in comparing1976 data (Midwest Research Institute 1976) tocurrent bottle masses (Keoleian 1997) Specificweight reduction data were not available for othermilk containers
Solid Waste GenerationThe total life-cycle solid waste is presented in
table 5 for each milk container Model resultsassuming a zero postconsumer recycling rateagreed well with results from previous studiesthat did not account for postconsumer recyclingThe model using the 1996 material productiondata set and 1995 recycling rates indicated thatthe HDPE 1-gal 50-trip refillable bottle gener-ated the least life-cycle solid waste (4 kg1000gal) whereas the single-use glass container gen-erated the most life-cycle solid waste (951 kg1000 gal) The relatively small difference be-tween the 1996 model case and previous studies
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 117
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
Table 3 Comparison of material production and total life cycle energy per 1000 gal of milk deliveredfrom previous studies with model results using 1990 and 1996 inventory data sets
Previous studies Model results Model results(1996) (1990)
Mat Mat Matprod Total Source prod Total prod Total
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
118 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 4 Effects of container weight reduction on total life-cycle energy use and solid waste per 1000gal of milk delivered
Life cycle energy use Life cycle solid wasteMJ ( change from base) kg ( change from base)
10 25 10 25Base reduction reduction Base reduction reduction
Note All results generated using the life-cycle inventory model
Theoretical 10 reduction in container weight
Theoretical 25 reduction in container weight
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 119
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
is due to differences in the solid waste factors formaterial production transportation and wash-ing For single-use milk containers postcon-sumer waste accounts for 90 of life-cycle solidwaste on average In the case of refillable con-tainers postconsumer waste accounts for 74 ofthe life-cycle solid waste The difference resultsfrom the waste associated with the washing andadditional transportation requirements for therefillable containers
The effects of recent changes in HDPE andglass recycling rates on total life-cycle solidwaste are also indicated in table 5 The corre-sponding recycling rates are shown in table 1 Ingeneral the variation in the recent national av-erage recycling rates did not have a dramatic ef-fect on the total life-cycle solid waste Strongcorrelations exist for both container weight re-duction (table 4) and postconsumer recyclingwith the total life-cycle solid waste Weight re-duction of the container a source reductionstrategy will have a slightly greater impact on
total life-cycle solid waste reduction than is ob-served for an equivalent percentage increase inthe recycle rate
Cost Assessment
The total life-cycle costs for each containerper 1000 gal of milk delivered are indicated intable 6 These costs ranged from $44 for 50-triprefillable HDPE containers to $1039 for single-use glass bottles For the single container systemsshown in table 6 empty container costs repre-sent 79 of the total on average Costs for refill-able container systems are less dependent onempty container costs than are single-use sys-tems Container costs accounted for 51 of thelife-cycle cost for high-trippage refillable sys-tems A sensitivity analysis of tipping fees on thenet end-of-life cost for each container system isshown in figure 1 National average tipping feeswere very steady between 1993 and 1996 ($28ton in 1993 $29ton in 1994 $34ton in 1995
Figure 1 Effect of landfill tipping fee on end-of-life cost for container systems (12 gal containers)
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
120 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
Table 5 Comparison of model results for postconsumer and total life-cycle solid waste per 1000 gal ofmilk delivered with previous studies including variations in national average recycling rate
Model resultsPrevious studies with recycling
0 Recycling 0 Recycling 1995 1994 1993 1992
Post-Total Source consumer Total Total Total Total Total
Although the polycarbonate bottle manufacturer has a bottle buy-back program the percentage of discarded con-tainers recycled through this system is not known
Neg These containers reported to have a negligible recycle rate during the years studied
NA Data not available
Recycle rates for HDPE and glass provided in table 1
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 121
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
and $32ton in 1996) and consequently end-of-life costs would not change significantly Therange of tipping fees shown on the abscissa infigure 1 represents the regional variation for1995 The tipping fee over this range does havea strong effect (about 24) on the end-of-lifecost for single-use glass In contrast the tippingfee even at the extreme regional 1995 values of$8ton and $79ton has a very weak effect on thetotal life-cycle cost for all containers studiedThe largest variation was observed for glasssingle-use bottles where the life-cycle cost in-creased by only 6 when the tipping fee was in-creased from $8ton to $79ton The effects ofrecent fluctuations in the market value of re-cycled material on the end-of-life cost for eachcontainer were examined in figure 2 HDPEshowed the most dramatic change betweenApril 1995 and April 1996 the price of recycledHDPE decreased to one-third its initial valueand the end-of-life cost increased by 41 Simi-lar to the tipping fee case a sensitivity analysisof recycled material prices indicated that thisparameter did not have a major effect on the to-tal life-cycle costs even though prices showedsignificant volatility over a 3-year period The
greatest change was found for a single-use HDPEbottle where a 67 drop in the price of recycledHDPE led to only a 3 increase in the total life-cycle cost The sensitivity analysis results for thetipping fee and the recycled material marketvalue support previous findings indicating thatthe total life-cycle cost is dominated by theempty container price
Other anecdotal information regarding refill-able bottles provides some insight into their lim-ited success in the marketplace In general arelatively significant deposit is required on refill-able bottles (generally more than 50 cents) Thisincrease in the purchase cost of milk sold in re-fillable containers may discourage many custom-ers If the deposit is reduced bottle return ratesdrop significantly and bottle replacement ex-penses incurred by dairies increase accordingly
Performance
A qualitative evaluation of each milk con-tainer system is indicated in table 7 The overallperformance represents an average of the scoresfor the six performance criteria The HDPE re-fillable and single-use bottles had high scores for
Table 6 Life-cycle costs of 05-gal milk containers (values rounded to the nearest dollar) ($1000 gal)
Empty of Transportation End of Life-cycleContainer Trips container $ total filling $ life $ cost $
End-of-Life = recycling incineration and landfill disposal
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
122 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
most performance criteria leading to an overallbest performance rating The single-use and re-fillable glass containers had a low overall scorebecause of their potential for breakage transpar-ency and relatively high weight The limitationsof the paperboard carton are its potential forleakage and its difficulty in opening particularlyfor the elderly (Sfiligoj 1994)
In the case of refillable containers merchantsmust accommodate returns of refillable contain-ers whereas consumers must be responsible forrinsing and returning them to the grocery storeA return infrastructure has been established inbottle bill states although the trend is shiftingalmost exclusively toward recycling nonrefill-able containers Even though returns may beconsidered inconvenient nonreturnable pack-aging also requires some type of consumer ac-tion either through trash disposal or recyclingThe polycarbonate refillable container had simi-
lar ratings as the HDPE refillable except that itis less able to block ultraviolet light which hasthe potential to lead to losses in nutritionalvalue (Dexheimer 1993)
The weak attributes of the pouch are its vul-nerability to puncture and its resealability limita-tions A pitcher which must be cleanedperiodically is required to hold the pouch and fa-cilitate pouring and storage Thus although cur-rently popular in regional markets both thepouch and refillable bottles exhibit clear perfor-mance trade-offs that limit their successful mar-ket penetration
Design Guidelines andRecommendations
Design guidelines for milk packaging weredeveloped from the analyses of life-cycle inven-tory results presented in tables 3 to 5 Based on
Figure 2 Trends in end-of-life cost due to variations in recycled material value between 1995 and 1997(12-gal containers) Recycled material values for HDPE and glass are shown in table 2
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 123
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
life-cycle solid waste and energy data for a vari-ety of container systems the following two envi-ronmental guidelines for container design areproposed
Minimize total life-cycle energy by mini-mizing material production energy par-ticularly for single-use containers Thiscan be achieved by using less energy-in-tensive materials and reducing the mate-rial intensity of each container Makingboth single-use and refillable containerslighter will also reduce transportation en-ergy requirements For refillable contain-ers high refill rates will reduce thecontribution of the material productionenergy to the total life-cycle energy on aunit delivered basis
Minimize total life-cycle solid waste byminimizing postconsumer solid wasteThis can be achieved through reductionsin container weight per volume deliveredand through achieving high refill rateswith refillable systems
A special caveat must be stated here regardingthese guidelines They do not address environ-mental impacts related to air emissions and wa-ter effluents and do not distinguish betweentypes of solid waste In addition resource deple-tion and scarcity issues for elemental flows(originating from the earth) of materials and en-ergy were not considered Therefore these
guidelines are limited in their ability to facilitatethe design or selection of container systems withthe least overall environmental impact Specialcaution should be exercised when applying theseguidelines to other beverage container systemshowever functionally similar systems should fol-low similar patterns for the distribution of solidwaste and energy across the life cycle
Another design guideline can be deducedfrom an analysis of life-cycle cost results Table 6indicates that empty container costs contributeda majority of the total life-cycle costs conse-quently the following guideline is proposed
Minimize total life-cycle costs by minimiz-ing empty container cost on a per-volumebasis
This can be achieved by either high trippagerate for refillable bottles or by limiting materialand fabrication costs for single-use containersLife-cycle cost represents the costs to societythat are reflected in the marketplace Externali-ties such as possible global warming caused bygreenhouse gas emissions were not included intotal life-cycle cost
Conclusions
The life-cycle inventory and cost analysistools were applied to milk packaging to guideenvironmental improvements through betterdesign Simplified design guidelines for improv-
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
124 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
ing the environmental performance of milkpackaging were recommended based on resultsfrom the inventory model developed herein andan analysis of previous life-cycle inventory stud-ies For single-use containers the total life-cycleenergy can be approximated by computing thematerial production energy of the package Forthis reason less energy-intensive materialsshould be encouraged along with less material-intensive containers For refillable containershigh refill rates should be achieved to best ex-ploit the initial energy investment in the pro-duction of the container Life-cycle solid waste islargely determined by postconsumer packagingwaste consequently less material-intensive con-tainers in general should be emphasized
The packaging community does not have easyaccess to life-cycle inventory data or the resourcesto perform rigorous life-cycle inventory studies ona routine basis The metrics and guidelines devel-oped in this study are intended to respond tothese limitations As published life-cycle data be-come more widely available and techniques forimpact assessment are further developed addi-tional metrics addressing ecological and humanhealth consequences caused by air pollutantemissions and water pollutant effluents and re-source depletion issues should be established formilk and juice packaging These metrics willcomplement the metrics proposed here and willprovide a more comprehensive measure of a pack-aging systemrsquos environmental performance
Close agreement in the relative rankings ofcontainer systems was found between results fromprevious studies and the inventory model devel-oped in this article Milk packaging and beveragecontainers in general are relatively simple prod-uct systems to analyze because of their single-ma-terial composition It is expected that variabilityamong studies would be greater for more complexproduct systems when more assumptions andjudgments must be made regarding system bound-aries and allocation rules Sensitivity and sce-nario analyses were useful in exploring theimportance of material production inventory pa-rameters container mass and recycling rates ontotal life-cycle energy solid waste and cost
The life-cycle cost analysis showed that theempty container cost was the major determinantof total life-cycle cost which also includes the
transportation filling and end-of-life costs suchas collection and disposal Volatility in the mar-ket value of recycled materials and the dramaticregional variation in tipping fees did not have asignificant impact on the total life-cycle cost
Analysis of milk container systems high-lighted both trade-offs and some consistent pat-terns for environmental cost and performancecriteria Refillable HDPE and polycarbonatebottles and the flexible pouch were shown to bethe most environmentally preferable containerswith respect to life-cycle energy and solid wastecriteria These containers were also found tohave the least life-cycle costs The strong corre-lation between least life-cycle cost and least life-cycle environmental burden indicates that themarket system could potentially encourage theseenvironmentally preferable containers For thisto occur retailers would have to account forcontainer costs more accurately in pricing milkIn other cases significant externalities (environ-mental burdens) not reflected in the market sys-tem may also create a barrier for marketpenetration of an environmentally preferablecontainer The ideal container would combinethe following attributes low fabrication costbarrier properties comparable to glass lowweight and shatter resistance afforded by plas-tics resealability (screw-on top) low materialproduction energy per unit delivered low mate-rial production of solid waste per unit deliveredand high end-of-life recyclability (dependent oninfrastructure) These characteristics apply toboth single-use and refillable container systems
Performance factors currently influence theoverall viability of alternative container systemsmuch more significantly than environmentalburdens Several performance criteria were high-lighted that present potential barriers to other-wise environmentally preferable containers suchas the refillable bottles and pouches Containersthat require significant changes in merchandis-ing andor consumer practices will encountermarket resistance Public education about theenvironmental merits of these systems may berequired to influence their acceptance
In addition to cost and performance govern-ment policies and regulations can potentiallyinfluence the design of container packagingThe diverse and complex policies and regula-
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
Keoleian and Spitzley Improving Life-Cycle Design and Management of Milk Packaging 125
A P P L I C AT I O N S AN D I M P L E M EN TAT I O N y
tions related to packaging systems include feesand taxes municipalstatefederal goals bansand mandates recyclingwaste minimization re-quirements and manufacturer packaging re-quirements (Keoleian et al 1997) The networkof regulatory and policy incentives and con-straints is not balanced in its coverage of the to-tal life-cycle system In particular currentpolicies and regulations tend to focus mainly onthe recycling of postconsumer packaging wasteThis emphasis could favor less environmentallypreferable packaging such as single-use glasscontainers over a pouch system that results inless total life-cycle energy and waste Regula-tions that support postconsumer solid wasteminimization should be encouraged but instru-ments that focus on discrete stages must be de-veloped in a fashion that does not eliminatepackaging systems that are preferable from a to-tal life-cycle perspective This narrow perspec-tive was also observed for consumers whoseperception of environmental performance wasbased on single attributes such as material typeand returnability which often conflicted withlife-cycle assessments (Van Dam 1996) Glassrefillable bottles were perceived to be muchmore environmentally preferable than plasticrefillables In general consumers lack informa-tion about the environmental profiles of pack-ages and related costs and consequently givelittle attention to this factor in milk purchasesThe metrics established in this study can helpeducate the public milk distributors retailerspackaging designers material suppliers andpolicymakers about the environmental conse-quences of milk and juice packaging
Acknowledgments
This manuscript is based on a Life Cycle De-sign Demonstration Project conducted with DowChemical Company We would like to thank JeffMcDaniel (former graduate student researcher atthe University of Michigan) Scott Noesen(Dow Project Leader) and Tony Kingsbury(Dow) for their valuable roles in this project
This project was wholly funded by the USEnvironmental Protection Agency under Assis-tance Agreement CR 822998-01-0 to the Uni-versity of Michigan Kenneth Stone is the
project officer at the US EPA National RiskManagement Research Laboratory The con-tents do not necessarily reflect the views andpolic ies of the US EPA Mention of tradenames or commercial products does not consti-tute endorsement or recommendation for use
Notes
1 Editorrsquos note For a discussion of the influence ofvariation in datasets on LCA results see E CopiusPeereboom et al Influence of inventory data setson life-cycle assessment results A case study onPVC Journal of Industrial Ecology 2(3) 109ndash130(1999)
2 A loss leader is merchandise sold at or below re-tailer cost that draws customers into a store and isintended to create additional purchases that maynot have occurred otherwise
References
BioCycle 1994ndash1997 (April issues) The state of gar-bage BioCycle nationwide survey BioCycle
Boustead I 1997 Eco-profiles of the European plasticsindustry Report 13 Polycarbonate Brussels As-sociation of Plastics Manufacturers in Europe
Boustead I 1995 Eco-profiles of the European plasticsindustry report 8 Polyethylene terephthalate (PET)Brussels Association of Plastic Manufacturers inEurope Technical and Environmental Centre
Boustead I and B R Yaros 1994 Electricity supplyindustry in North America Resources Conserva-tion and Recycling 12 121ndash134
Calder Dairy 1997 Personal communication Lin-coln Park MI
Dairy Industri es Internat ional 1994 NCF Sligolaunches first 15 L carton Dairy Industries Inter-national 59(6) 47
Deloitte and Touche 1991 Energy and environmentalimpact profiles in Canada of tetra brik aseptic cartonand glass bottle packaging systems Deloitte andTouche
Dexheimer E 1993 Fighting the light Campaignaims to sell more milk packaged in paperboardDairy Foods Magazine 94(9) 81
Dostal amp Lowey Manufacturing Company Inc 1997Personal communication Menomonee Falls Wis
Dover S E Madden M Common and S Boyden1993 Milk packaging in Australia A case studyin environmental priorities Resources Conser-vation and Recycling 9 61ndash73
EPIC 1997 The evolution of milk packaging and the ef-
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
126 Jour nal of Industrial Ecology
y AP P L I C AT I O N S A N D I M P L E M EN TAT I O N
fect on solid waste in Ontario from 1968 to 1995Mississauga Ontario Environment and PlasticsIndustry Council
Erickson G 1988 Milk in bag finds niche saves $Packaging 33 8ndash10
Franklin Associates 1990 Comparative energy evalua-tion of plastic products and their alternatives for thebuilding and construction and transportation indus-tries Prairie Village KS Franklin Associates
Franklin Associates 1991 Resource and environmentalprofile analysis of high-densit y polyethylen e andbleached paperboard gable milk containers PrairieVillage KS Franklin Associates
Franklin Associates 1992 Appendix A Energy require-ments and environmental emissions for fuel consump-tion Prairie Village KS Franklin Associates
Franklin Associates 1994 The role of recycling in inte-grated solid waste management to the year 2000Stamford CT Keep America Beautiful Inc
HarborSide Research 1994 Estimated price per ton ofcommon packages
Keoleian G A 1997 Unpublished dataKeoleian G A J Koch and D Menerey 1995 Life
cycle design framework and demonstration projectsProfiles of ATampT and AlliedSignal EPA600R-95107 US Environmental Protection AgencyNational Risk Management Research Labora-tory Cincinnati Ohio
Keoleian G A and J S McDaniel 1997 Life cycledesign of instrument panels A common senseapproach SAE International Congress and Expo-sition Warrendale PA SAE InternationalTechnical Paper 970695
Keoleian G A and D Menerey 1993 Life cycle de-sign guidance manual Environmental requirementsand the product system US EPA Office of Re-search and Development Risk Reduction Engi-neering Laboratory Cincinnati Ohio
Keoleian G A D V Spitzley and J McDaniel1997 Life cycle design of milk and juice packagingEPA 600R-97082 (NTIS 1-800-553 -6847)US Environmental Protection Agency Officeof Research and Development National RiskManagement Research Laboratory CincinnatiOhio
Kooijman J M 1993 Environmental assessment ofpackaging Sense and sensibility EnvironmentalManagement 17(5) 575ndash586
Kuta C C D G Koch C C Hildebrandt and D CJanzen 1995 Improvement of products and pack-aging through the use of life cycle analysis Re-sources Conservation and Recycling 14 185ndash198
Lundholm M P and G Sundstrom 1985 Tetra brikaseptic environmental profile Resource and envi-
ronmental impact of tetra brik aseptic carton and ofrefillable glass bottles Malmo Sweden Tetra Pak173 pp report
Midwest Research Institute 1976 Resource and environ-mental profile analysis of five milk container systemswith selected health and economic considerationsWashington DC United States EnvironmentalProtection Agency
Oberwise Dairy 1997 Personal communication Au-rora IL
Porter W J 1993 Recycling at the crossroads SterlingVA Porter and Associates
PPI 1995 Life-cycle inventory analysis Thermoplasticresin fabrication conversion processes a preliminarystudy Polymer Processing Institute at StevensInstitute of Technology Hoboken NJ
Recycling Times 1995 (Jan 24 April 18 July 25Oct 17) 1997 (Jan 20 April 28 July 21 Oct13 1997 issues include data on previous year)The Markets Page Waste Agersquos Recycling Times
Saphire D 1994 Case reopened Reassessing refillablebottles New York INFORM
SETAC 1993 Workshop reportmdashguidelines for life-cycleassessment A code of practice Pensacola FL Soci-ety of Environmental Toxicology and Chemistry
Sfiligoj E 1994 Spouting off Beverage World (Octo-ber) 233
Stanpac Inc 1997 Personal communication LewistonNY
Stewartrsquos Dairy 1997 Personal communicatio nSaratoga Springs NY
Swiss FOEFL 1991 Ecobalance of packaging materialsstate of 1990 Berne Switzerland Swiss FederalOffice of Environment Forests and Landscape
Swiss FOEFL 1996 Oumlkoinventare fuumlr VerpackungenBerne Switzerland Swiss Federal Office of Envi-ronment Forests and Landscape
Swope T 1995 New wine from old bottles The En-vironmental Magazine 6(4) 32ndash35
Urbanski A 1991 Torn between two bottles OceanSpray test markets two beverage package sizesFood amp Beverage Marketing 10(11) 38
US EPA 1995 Life cycle impact assessment A concep-tual framework key issues and summary of existingmethods EPA-452R-95-002 Research TrianglePark NC US Environmental Protect ionAgency Office of Air Quality
US EPA 1997 Characterization of municipal solid wastein the United States 1996 update EPA530-R-97-015 United States Environmental ProtectionAgency Solid Waste and Emergency Response
Van Dam Y K 1996 Environmental assessment ofpackaging The consumer point of view Environ-mental Management 20(5) 607ndash614
