Research ArticleVegetable Contamination by the Fecal Bacteria of PoultryManure Case Study of Gardening Sites in Southern Benin
Seacuteraphin C Atideacutegla1 Joeumll Huat2 Euloge K Agbossou1
Herveacute Saint-Macary3 and Romain Glegravelegrave Kakai1
1Faculte des Sciences Agronomiques Universite drsquoAbomey-Calavi 01 BP 526 Cotonou Benin2CIRAD UPR HortSys 34498 Montpellier Cedex 05 France3CIRAD UPR Recyclage et Risque 34398 Montpellier Cedex 05 France
Correspondence should be addressed to Seraphin C Atidegla atideglasergmailcom
Received 3 November 2015 Accepted 14 February 2016
Academic Editor Marie Walsh
Copyright copy 2016 Seraphin C Atidegla et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited
A study was conducted in southern Benin to assess the contamination of vegetables by fecal coliforms Escherichia coli andfecal streptococci as one consequence of the intensification of vegetable cropping through fertilization with poultry manure Forthis purpose on-farm trials were conducted in 2009 and 2010 at Yodo-Condji and Ayi-Guinnou with three replications andfour fertilization treatments including poultry manure and three vegetable crops (leafy eggplant tomato and carrot) Samplinglaboratory analyses and counts of fecal bacteria in the samples were performed in different cropping seasons Whatever thefertilization treatment the logs of mean fecal bacteria count per g of fresh vegetables were variable but higher than AFNOR criteriaThe counts ranged from 8 to 10 fecal coliforms from 5 to 8 fecal streptococci and from 2 to 6 Escherichia coli whereas AFNORcriteria are respectively 0 1 and 0The long traditional use of poultry manure and its use during the study helped obtain this highpopulation of fecal pathogens Results confirmed that the contamination of vegetables by fecal bacteria is mainly due to the useof poultry manure The use of properly composted poultry manure with innovative cropping techniques should help reduce thenumber and incidence of pathogens
1 Introduction
In Sub-Saharan Africa the products of urban agriculture areconsidered to be one response to the shortage of foodstuffs[1] In addition to the contributions of urban agriculture tourban food security nutrition and local economies farmingalso affects urban water management sanitation and healthservices [2] In that context urban production of vegetablesis increasing rapidly but in both Africa and Asia faces manyconstraints especially land pressure access to water and lowsoil fertility [3ndash5] In Benin West Africa the same problemshave been identified in periurban and urban gardening areaswhere irrigated vegetable production developed rapidly after1990 coinciding with the drastic drop in fish resources in theAtlanticOcean and in the riversThemain vegetable crops areleafy vegetables eggplant (Solanum macrocarpon L) carrots
To satisfy the increasing demand for vegetables despitethe poverty of coastal soils and land pressure farmers tend tointensify production by using mineral and organic fertilizersand pesticides Today animal manure (60 poultry manureand 40 cattle manure) is frequently used as fertilizer inthe study area Grand-Popo in Benin Animal manures havebeen used as effective fertilizers for centuries [6 7] Brookset al [8] investigated potential microbial runoff associatedwith the application of poultry litter on the soil Several otherstudies pointed to pollution and health risks caused by lack ofknowledge and bad practices in the management of livestockmanure and chemical fertilizers [1 3 9]
Excessive use of fertilizer at each agricultural campaignhas been reported in both Africa and Asia particularly the
Hindawi Publishing CorporationInternational Journal of Food ScienceVolume 2016 Article ID 4767453 8 pageshttpdxdoiorg10115520164767453
2 International Journal of Food Science
use of poultry manure at rates of 20 to 50 tsdothaminus1 and theuse of mineral fertilizers such as urea and NPK (10-20-20nitrogen phosphorus and potassium fertilizer) at rates of 12to 2 tsdothaminus1 [6 9] Unfortunately the intensive use of organicmatter like cow dung and poultry manure and other animalfeces are a significant environmental risk to soils waters andcrops including fecal contamination [6]
Many infection outbreaks have been associated withwater or food directly or indirectly contaminated by animalmanure [10 11] by identifying Escherichia coli and fecalcoliforms which are indicators of fecal pollution [12 13] Onesuch examplewas amajorwaterborne outbreak ofEscherichiacoli O157H7 (ECO157) infections with bloody diarrhea andabdominal cramps which lasted from 15 December 1989 to20 January 1990 in Missouri [14] Griffin et al [15] reportedthe occurrence ofmany outbreaks of Escherichia coliO157H7(ECO157) infections in communities nursing homes a daycare center and a kindergarten They mainly took the formof gastrointestinal diseases bloody diarrhea hemolytic ure-mic syndrome or thrombotic thrombocytopenic purpuraContaminated manure can contact the product directlywhen used as a soil fertilizer or indirectly via infiltrationof irrigation water or infiltration of water used to wash theproduct Ibenyassine et al [16] and Steele et al [17] reportedthat contaminated irrigation water and surface runoff watermay be major sources of pathogenic microorganisms thatcontaminate fruits and vegetables in fields Animal fecesincluding poultry manure which contain large numbersof bacteria can contaminate croplands and hence agricul-tural products Fecal bacteria including Escherichia coli areresponsible for serious outbreaks of diarrhea particularlyin children Some of these microorganisms including fecalcoliforms Escherichia coli and fecal streptococci are life-threatening Gastrointestinal diseases are ranked as the sec-ond most important health problem after malaria for mostcommunities in Accra Ghana especially in high-densitylow-income areas Elderly and immune-depressed patientsare also exposed to the risk of gastrointestinal problemsOther infectious diseases including hepatitis typhoid andparatyphoid fever meningitis and skin diseases can also becaused by fecal contamination [18ndash20]
According to the literature few studies have dealt with thelink between the presence of pathogens in freshly harvestedvegetables and the wide use of organic material such aspoultry manure as fertilizer in market gardening in tropicaldeveloping countries [1 21] One risk of the intensive use ofsuch organic waste is fecal contamination of the vegetables[3] Today poor practices used for the management oflivestock manure and chemical fertilizers remain the same asthose reported in 2009-2010 since the farmers in the studyarea have not adopted alternative practices
In the present study this issue was addressed by assessingthe microbiological quality of vegetables cultivated in marketgardening areas in the coastal area of southern Benin Life-threatening pathogens (fecal coliforms Escherichia coli andfecal streptococci) were counted both in the poultry manureand in the fresh vegetables after harvest Both irrigationwaterand the cultivated soil were analyzed The main reason why
this study focuses on fecal coliforms Escherichia coli andfecal streptococci is that Escherichia coli is an ideal indicatorof hygiene in microbiological analyses of raw foods like freshvegetables The origin of these fecal pathogens was identifiedwith the aim of recommending ways to reduce these risks
2 Materials and Methods
21 Study Area The study was conducted in 2009 and 2010 inthe coastal area of southern Benin at market gardening sitesin Yodo-Condji (01∘4610158403310158401015840N-06∘1010158401010158401015840E district of Grand-Popo) and Ayi-Guinnou (01∘4410158403610158401015840N-06∘1510158404810158401015840E district ofAgoue)
The climate is subequatorial characterized by little varia-tion in temperature (annual average 274∘C) and a bimodalrainfall pattern (annual average rainfall 882mm) Marinesandy soils very seeping and porous make up the two firstsoils layers (0ndash18 cm and 18ndash40 cm) with slightly basic pHbetween 73 and 75 [6] at the two sites The land has beencultivated continuously for several decades without fallow
Farmers have easy access to groundwater for crop irri-gation (through spraying water method) but are limited bythe low fertility of the coastal sandy soils To satisfy growingurban demand and to improve crop productivity they haveadopted intensive practices such as application of chemicalfertilizers combinedwith high rates of poultrymanure whichis available locally The length of the crop cycle of thesevegetables varies from 15 to 35 months enabling farmers tosuccessively cultivate four vegetable crops per year
22 Experimental Design At each site the experiment wasconducted in a split-plot design with two factors (4 fertiliza-tion treatments and 3 vegetable crops) and three replicationsduring four successive vegetable growing periods Each plotmeasured 2m2 (2m times 1m)
The four growing periods were from 5 May 2009 to 2September 2009 (period 1) during the long rainy season from10 September 2009 to 12 January 2010 (period 2) during theshort rainy season and the long dry season from 20 January2010 to 13 May 2010 (period 3) during the dry season and thelong rainy season and from 21 May 2010 to 15 August 2010(period 4) during the long rainy season and the short dryseason
The main factor analyzed was fertilization including thechemical fertilizers and poultry manure applied during eachgrowing period using four different treatments (Table 1)Thepoultry manure was composed of chicken feces and woodshavings and came from a local chicken farm
The second factor was the vegetable crop tomato (Lycop-ersicon esculentumM) traditional eggplant (Solanummacro-carpon L) or carrot (Daucus carota L) The vegetables wereharvested the same day and only once
23 Sampling and Analyses A total of 164 samples from thetwo sites were analyzed during the study At harvest timefor each plot and each crop five individual samples collectedfrom the four corners of the plot and one sample from themiddlewere pooled tomake a composite 100 g sample of fresh
International Journal of Food Science 3
Table 1 Fertilization modalities at each growing period application of poultry manure and mineral fertilizers on the three tested vegetablecrops (eggplant tomato and carrot) Amendment was applied one week before sowing top-dressing was applied twice 2 weeks and 4 weeksafter sowing (coastal area of Benin 2009-2010 288 plots)
Fertilization modalities Amendment (tsdothaminus1) Total top-dressing (tsdothaminus1) Total per growing period (tsdothaminus1)T0 control 0 0 0T1 farmer practice 1
vegetables The samples were immediately placed in sterilebags A total of 96 composite samples of fresh vegetableswere analyzed for the period of 2009-2010 Eight samplesof poultry manure were collected before each sowing dateOne kg of poultry manure was collected using the proceduredescribed above All samples of poultry manure were imme-diately sealed in sterile bags at 25∘C and transported to thelaboratory
Analyses of the different samples (poultry manure andvegetables) were performed by the ldquoWater and Food QualityControl Laboratory of the Ministry of Healthrdquo in CotonouAt the time this laboratory was the only one in Cotonouto perform microbiological analyses of both liquid and solidfoods During the study period a second laboratory whichwas only qualified for microbiology analyses in water hadproblems with its specific equipment But as soils and poultrymanure are solid and the target of the present study wasfecal pathogens samples of soils and poultry manures werealso sent to that qualified laboratory In the absence ofevidence from other organizations (FAO CEE and IRD)or other European recommendations that mention levels offecal pathogens recorded in soils and manure AFNOR foodand water criteria are used in the paper To our knowl-edge the purpose of the AFNOR criteria is to identify theconcentration of these pathogens in the substances likevegetables or water consumed by human beings For thisreason we compare our data concerning soils and poultrymanure with AFNOR criteria and analytical techniques
(i) Vegetables and Poultry Manure Note the following(a) Fecal coliforms per g were identified by colimetry
using the V-08-60 RapidrsquoE coli medium (24 h at44∘C)
(b) Escherichia coli per g were identified by colimetryusing the V-08-053 RapidrsquoE coli medium (24 h at44∘C)
(c) Fecal streptococci were identified by NFT 90416 andBartley and Slanetz medium (24 hndash48 h at 37∘C)
The number of fecal microorganisms per gram of com-posite sample of fresh vegetables or of poultry manure or ofsoils was used as the unit of measure
24 Data Analysis Analysis of variance on repeated mea-sures [22] was performed to test the effects of ldquogrowingperiodrdquo ldquofertilization treatmentrdquo ldquovegetable croprdquo and ldquositerdquoon the populations of microorganisms of soils while tra-ditional analysis of variance (nonrepeated measures) wasperformed to test the effects of the above-cited factors (exceptldquogrowing periodrdquo) on the populations of fecal microorgan-isms on the vegetables In the twomodels site was consideredas random factor while the other factors were fixed Thesestatistical analyses were conducted using SAS software ver-sion 92
To stabilize the variances each of the three variables (fecalcoliforms Escherichia coli and fecal streptococci) was log-transformed according to the following relation119910 = ln(119909+1)where 119909 is the number of bacteria observed for each variableand 119910 is the result of the transformation
The adjusted means of the three variables were compiledwith the corresponding coefficients of variation Student-Newman-Keuls (SNK) tests distinguished means by high-lighting the different groups of homogenous treatments
Factors able to explain the variability of the number offecal bacteria in the study area were identified
3 Results and Discussion
31 Changes in Populations of Fecal Bacteria in the PoultryManure as a Function of the Growing Period High temporalvariability of the number of fecal bacteria in the poultrymanure at the two sites was observed (Figure 1) Log-trans-formed fecal coliform counts increased from 5May 2009 to 2September 2009 (period 1) and from 10 September 2009 to 12January 2010 (period 2) Conversely log-transformed countsof Escherichia coli decreased from 4 in period 1 to slightly lessthan 4 in period 2 and were absent from 20 January 2010 to 13May 2010 (period 3) and from 21 May 2010 to 15 August 2010(period 4) The number of streptococci decreased frommorethan 6 in period 1 to slightly less than 6 in period 2 and thenincreased to 8 in period 3 before falling to slightly less than 4in period 4
The high temperatures (30∘C to 35∘C) betweenDecember2009 and January 2010 when the poultry manure was storedoutside the henhouse probably helped reduce populations
4 International Journal of Food Science
0123456789
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
Log
of m
ean
feca
l ger
ms c
ount
per g
of p
oultr
y m
anur
e
Fecal coliformsEscherichia coliFecal streptococci
Figure 1 Changes in populations of the three fecal microorganismsin poultry manure over the four growing periods (coastal area ofBenin 2009-2010)
of fecal coliforms by more than half (growing period 2 togrowing period 3) A similar situation was observed forEscherichia coli in irrigation water and soils at both sites buthere we rather witnessed their disappearance from period1 (harvest period) to period 3 However concerning thepoultry manure the untimely actions of the driving rainduring the trial could explain the variations that occurred inperiod 4 when the poultry manure was stored outside thehenhouse for two months (from April 2010 to May 2010)Rainfall amounted to 147mm in eight days from 1 April 2010to 12 April 2010 versus 16 days for the same volume duringthe same period in 2009 Driving rains could thus also havebeen responsible for the reduction in (or the absence of)microorganisms at some dates in particular Escherichia coliand fecal streptococci in the poultry manure taken from thehenhouse on 10 April 2010 and analyzed on 13 May 2010Thisobservation is in accordance with the results of Hutchisonet al [23] who contrasted the effect of driving rain on thesurvival of fecal coliforms causing their destruction andwashing them out with the effect of drizzle Like Jamieson etal [24] our results showed that bacterial survival was optimalin cold wet conditions But it is possible that competitionamong microorganisms also affects the survival of fecalbacteria in the soil in line with the influence of predation[25] In the study area predation among bacteria could alsobe responsible for the disappearance of fecal pathogens
Based on the results observed through Figure 1 it ispossible to conclude that because there was no organicmatter in the soil as soon as the poultry manure was appliedto the soil the fecal microorganisms remained on the surfaceand moved directly towards the vegetables Franz et al [26]reported that survival of Escherichia coli was optimal in soilsrich in organic matter and under flooding According tothese authors water holding capacity which depends on
soil texture and organic matter content is known to havean impact on fecal bacteria Analyses of poultry manure ingrowing period 4 (the wettest period) revealed the influenceof humidity As soils with a high humus ratio have the highestwater holding capacity they provide a favorable environmentfor the survival of fecal pathogens In conclusion in this studyarea a large proportion of the fecal bacteria supplied by thepoultry manure did not survive due to unfavorable abioticconditions (temperature pH and organic matter content)
32 High Level of Contamination of Harvested VegetablesIndividually site fertilization treatment and type of vege-table had no significant effect on the number of fecalmicroor-ganisms (Figures 2(a) 2(b) and 2(c)) Log-transformed fecalcoliform counts on vegetables were close to 10 that is higherthan those of Escherichia coli and fecal streptococci (eachclose to six) (Figure 3)
The number of populations of microorganisms variedconsiderably among the four growing periods and among thethree vegetables crops (Figures 2(a) 2(b) and 2(c)) From 5May 2009 to 13 May 2010 (three successive growing periods)fecal coliforms increased four times on carrot (28 to 107) andalmost two times on eggplant (48 to 85) In the same periodsfecal coliforms on tomato increased almost four times (from23 to 86) but decreased by half on both vegetables in period 4(Figures 2(a) 2(b) and 2(c)) On tomato (Figure 2(c)) fecalcoliforms increased from two in period 1 to nine in period3 before decreasing to four in period 4 The highest rateof contamination by fecal coliforms (lt11) on carrot and byEscherichia coli on eggplant (7) occurred in period 3 and inperiod 2 on carrot (lt9)The number of fecal coliforms on thevegetables reached its peak in periods 2 and 3 whereas thenumber of Escherichia coli (7) was highest in period 3 andthat of fecal streptococci (gt8) was highest in period 2 Fecalcoliforms were lowest (around 2) in period 1 Escherichiacoli were absent during some growing periods and fecalstreptococci were absent in period 4 (Figure 2(b))
In the vegetable samples the mean number of fecal bac-teria per gram was considerably higher than the levelsrecommended by the French Standards Association [27] forfresh vegetables (Table 2) 8 to 10 times higher than the stand-ard for fecal coliforms 2 to 6 times higher than the standardfor Escherichia coli and 5 to 8 times higher than the standardfor fecal streptococci
Although the original source of contamination of pro-duce has seldom been identified manure from farm ani-mals has long been suspected of being a leading vehicle ofpathogen transmission Concerning the different results andthe fact that the major source of contamination of freshproducts is microbial pathogens we agree with Ijabadeniyiet al [11] who reported that at the preharvest stage thesources include feces irrigation water inadequately com-posted manure soil air animals and human handling
33 Role of Poultry Manure in the Contamination of Vegeta-bles Considering all the treatments (T0 T1 T2 and T3)together we found all three types of fecal bacteria in the threevegetable crops (Figures 2(a) 2(b) and 2(c)) As shown by theresults of the analyses of variance (Table 3) at 119901 lt 005 only
International Journal of Food Science 5
02468
101214
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f car
rot
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(a)
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f egg
plan
t
(b)
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
m co
unt
per g
of t
omat
o
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(c)
Figure 2 (a) Changes in populations of fecal bacteria on carrot per growing period (sites and fertilization treatments considered together(coastal area of Benin 2009-2010 288 plots 32 samples)) (b) Changes in populations of fecal bacteria on eggplant per growing period (sitesand fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32 samples)) (c) Changes in populations of fecalbacteria on tomato per growing period (sites and fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32samples))
Table 2 Populations of fecal coliforms Escherichia coli and fecal streptococci on each crop (sites growing periods and fertilizationtreatments considered together) in comparison to AFNOR criteria (coastal area of Benin 2009-2010 288 plots 96 samples of all crops)
Log of mean fecal bacteriacounted per g of crop
Carrot Eggplant Tomato AFNOR criteriaM SD M SD M SD
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
use of poultry manure at rates of 20 to 50 tsdothaminus1 and theuse of mineral fertilizers such as urea and NPK (10-20-20nitrogen phosphorus and potassium fertilizer) at rates of 12to 2 tsdothaminus1 [6 9] Unfortunately the intensive use of organicmatter like cow dung and poultry manure and other animalfeces are a significant environmental risk to soils waters andcrops including fecal contamination [6]
Many infection outbreaks have been associated withwater or food directly or indirectly contaminated by animalmanure [10 11] by identifying Escherichia coli and fecalcoliforms which are indicators of fecal pollution [12 13] Onesuch examplewas amajorwaterborne outbreak ofEscherichiacoli O157H7 (ECO157) infections with bloody diarrhea andabdominal cramps which lasted from 15 December 1989 to20 January 1990 in Missouri [14] Griffin et al [15] reportedthe occurrence ofmany outbreaks of Escherichia coliO157H7(ECO157) infections in communities nursing homes a daycare center and a kindergarten They mainly took the formof gastrointestinal diseases bloody diarrhea hemolytic ure-mic syndrome or thrombotic thrombocytopenic purpuraContaminated manure can contact the product directlywhen used as a soil fertilizer or indirectly via infiltrationof irrigation water or infiltration of water used to wash theproduct Ibenyassine et al [16] and Steele et al [17] reportedthat contaminated irrigation water and surface runoff watermay be major sources of pathogenic microorganisms thatcontaminate fruits and vegetables in fields Animal fecesincluding poultry manure which contain large numbersof bacteria can contaminate croplands and hence agricul-tural products Fecal bacteria including Escherichia coli areresponsible for serious outbreaks of diarrhea particularlyin children Some of these microorganisms including fecalcoliforms Escherichia coli and fecal streptococci are life-threatening Gastrointestinal diseases are ranked as the sec-ond most important health problem after malaria for mostcommunities in Accra Ghana especially in high-densitylow-income areas Elderly and immune-depressed patientsare also exposed to the risk of gastrointestinal problemsOther infectious diseases including hepatitis typhoid andparatyphoid fever meningitis and skin diseases can also becaused by fecal contamination [18ndash20]
According to the literature few studies have dealt with thelink between the presence of pathogens in freshly harvestedvegetables and the wide use of organic material such aspoultry manure as fertilizer in market gardening in tropicaldeveloping countries [1 21] One risk of the intensive use ofsuch organic waste is fecal contamination of the vegetables[3] Today poor practices used for the management oflivestock manure and chemical fertilizers remain the same asthose reported in 2009-2010 since the farmers in the studyarea have not adopted alternative practices
In the present study this issue was addressed by assessingthe microbiological quality of vegetables cultivated in marketgardening areas in the coastal area of southern Benin Life-threatening pathogens (fecal coliforms Escherichia coli andfecal streptococci) were counted both in the poultry manureand in the fresh vegetables after harvest Both irrigationwaterand the cultivated soil were analyzed The main reason why
this study focuses on fecal coliforms Escherichia coli andfecal streptococci is that Escherichia coli is an ideal indicatorof hygiene in microbiological analyses of raw foods like freshvegetables The origin of these fecal pathogens was identifiedwith the aim of recommending ways to reduce these risks
2 Materials and Methods
21 Study Area The study was conducted in 2009 and 2010 inthe coastal area of southern Benin at market gardening sitesin Yodo-Condji (01∘4610158403310158401015840N-06∘1010158401010158401015840E district of Grand-Popo) and Ayi-Guinnou (01∘4410158403610158401015840N-06∘1510158404810158401015840E district ofAgoue)
The climate is subequatorial characterized by little varia-tion in temperature (annual average 274∘C) and a bimodalrainfall pattern (annual average rainfall 882mm) Marinesandy soils very seeping and porous make up the two firstsoils layers (0ndash18 cm and 18ndash40 cm) with slightly basic pHbetween 73 and 75 [6] at the two sites The land has beencultivated continuously for several decades without fallow
Farmers have easy access to groundwater for crop irri-gation (through spraying water method) but are limited bythe low fertility of the coastal sandy soils To satisfy growingurban demand and to improve crop productivity they haveadopted intensive practices such as application of chemicalfertilizers combinedwith high rates of poultrymanure whichis available locally The length of the crop cycle of thesevegetables varies from 15 to 35 months enabling farmers tosuccessively cultivate four vegetable crops per year
22 Experimental Design At each site the experiment wasconducted in a split-plot design with two factors (4 fertiliza-tion treatments and 3 vegetable crops) and three replicationsduring four successive vegetable growing periods Each plotmeasured 2m2 (2m times 1m)
The four growing periods were from 5 May 2009 to 2September 2009 (period 1) during the long rainy season from10 September 2009 to 12 January 2010 (period 2) during theshort rainy season and the long dry season from 20 January2010 to 13 May 2010 (period 3) during the dry season and thelong rainy season and from 21 May 2010 to 15 August 2010(period 4) during the long rainy season and the short dryseason
The main factor analyzed was fertilization including thechemical fertilizers and poultry manure applied during eachgrowing period using four different treatments (Table 1)Thepoultry manure was composed of chicken feces and woodshavings and came from a local chicken farm
The second factor was the vegetable crop tomato (Lycop-ersicon esculentumM) traditional eggplant (Solanummacro-carpon L) or carrot (Daucus carota L) The vegetables wereharvested the same day and only once
23 Sampling and Analyses A total of 164 samples from thetwo sites were analyzed during the study At harvest timefor each plot and each crop five individual samples collectedfrom the four corners of the plot and one sample from themiddlewere pooled tomake a composite 100 g sample of fresh
International Journal of Food Science 3
Table 1 Fertilization modalities at each growing period application of poultry manure and mineral fertilizers on the three tested vegetablecrops (eggplant tomato and carrot) Amendment was applied one week before sowing top-dressing was applied twice 2 weeks and 4 weeksafter sowing (coastal area of Benin 2009-2010 288 plots)
Fertilization modalities Amendment (tsdothaminus1) Total top-dressing (tsdothaminus1) Total per growing period (tsdothaminus1)T0 control 0 0 0T1 farmer practice 1
vegetables The samples were immediately placed in sterilebags A total of 96 composite samples of fresh vegetableswere analyzed for the period of 2009-2010 Eight samplesof poultry manure were collected before each sowing dateOne kg of poultry manure was collected using the proceduredescribed above All samples of poultry manure were imme-diately sealed in sterile bags at 25∘C and transported to thelaboratory
Analyses of the different samples (poultry manure andvegetables) were performed by the ldquoWater and Food QualityControl Laboratory of the Ministry of Healthrdquo in CotonouAt the time this laboratory was the only one in Cotonouto perform microbiological analyses of both liquid and solidfoods During the study period a second laboratory whichwas only qualified for microbiology analyses in water hadproblems with its specific equipment But as soils and poultrymanure are solid and the target of the present study wasfecal pathogens samples of soils and poultry manures werealso sent to that qualified laboratory In the absence ofevidence from other organizations (FAO CEE and IRD)or other European recommendations that mention levels offecal pathogens recorded in soils and manure AFNOR foodand water criteria are used in the paper To our knowl-edge the purpose of the AFNOR criteria is to identify theconcentration of these pathogens in the substances likevegetables or water consumed by human beings For thisreason we compare our data concerning soils and poultrymanure with AFNOR criteria and analytical techniques
(i) Vegetables and Poultry Manure Note the following(a) Fecal coliforms per g were identified by colimetry
using the V-08-60 RapidrsquoE coli medium (24 h at44∘C)
(b) Escherichia coli per g were identified by colimetryusing the V-08-053 RapidrsquoE coli medium (24 h at44∘C)
(c) Fecal streptococci were identified by NFT 90416 andBartley and Slanetz medium (24 hndash48 h at 37∘C)
The number of fecal microorganisms per gram of com-posite sample of fresh vegetables or of poultry manure or ofsoils was used as the unit of measure
24 Data Analysis Analysis of variance on repeated mea-sures [22] was performed to test the effects of ldquogrowingperiodrdquo ldquofertilization treatmentrdquo ldquovegetable croprdquo and ldquositerdquoon the populations of microorganisms of soils while tra-ditional analysis of variance (nonrepeated measures) wasperformed to test the effects of the above-cited factors (exceptldquogrowing periodrdquo) on the populations of fecal microorgan-isms on the vegetables In the twomodels site was consideredas random factor while the other factors were fixed Thesestatistical analyses were conducted using SAS software ver-sion 92
To stabilize the variances each of the three variables (fecalcoliforms Escherichia coli and fecal streptococci) was log-transformed according to the following relation119910 = ln(119909+1)where 119909 is the number of bacteria observed for each variableand 119910 is the result of the transformation
The adjusted means of the three variables were compiledwith the corresponding coefficients of variation Student-Newman-Keuls (SNK) tests distinguished means by high-lighting the different groups of homogenous treatments
Factors able to explain the variability of the number offecal bacteria in the study area were identified
3 Results and Discussion
31 Changes in Populations of Fecal Bacteria in the PoultryManure as a Function of the Growing Period High temporalvariability of the number of fecal bacteria in the poultrymanure at the two sites was observed (Figure 1) Log-trans-formed fecal coliform counts increased from 5May 2009 to 2September 2009 (period 1) and from 10 September 2009 to 12January 2010 (period 2) Conversely log-transformed countsof Escherichia coli decreased from 4 in period 1 to slightly lessthan 4 in period 2 and were absent from 20 January 2010 to 13May 2010 (period 3) and from 21 May 2010 to 15 August 2010(period 4) The number of streptococci decreased frommorethan 6 in period 1 to slightly less than 6 in period 2 and thenincreased to 8 in period 3 before falling to slightly less than 4in period 4
The high temperatures (30∘C to 35∘C) betweenDecember2009 and January 2010 when the poultry manure was storedoutside the henhouse probably helped reduce populations
4 International Journal of Food Science
0123456789
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
Log
of m
ean
feca
l ger
ms c
ount
per g
of p
oultr
y m
anur
e
Fecal coliformsEscherichia coliFecal streptococci
Figure 1 Changes in populations of the three fecal microorganismsin poultry manure over the four growing periods (coastal area ofBenin 2009-2010)
of fecal coliforms by more than half (growing period 2 togrowing period 3) A similar situation was observed forEscherichia coli in irrigation water and soils at both sites buthere we rather witnessed their disappearance from period1 (harvest period) to period 3 However concerning thepoultry manure the untimely actions of the driving rainduring the trial could explain the variations that occurred inperiod 4 when the poultry manure was stored outside thehenhouse for two months (from April 2010 to May 2010)Rainfall amounted to 147mm in eight days from 1 April 2010to 12 April 2010 versus 16 days for the same volume duringthe same period in 2009 Driving rains could thus also havebeen responsible for the reduction in (or the absence of)microorganisms at some dates in particular Escherichia coliand fecal streptococci in the poultry manure taken from thehenhouse on 10 April 2010 and analyzed on 13 May 2010Thisobservation is in accordance with the results of Hutchisonet al [23] who contrasted the effect of driving rain on thesurvival of fecal coliforms causing their destruction andwashing them out with the effect of drizzle Like Jamieson etal [24] our results showed that bacterial survival was optimalin cold wet conditions But it is possible that competitionamong microorganisms also affects the survival of fecalbacteria in the soil in line with the influence of predation[25] In the study area predation among bacteria could alsobe responsible for the disappearance of fecal pathogens
Based on the results observed through Figure 1 it ispossible to conclude that because there was no organicmatter in the soil as soon as the poultry manure was appliedto the soil the fecal microorganisms remained on the surfaceand moved directly towards the vegetables Franz et al [26]reported that survival of Escherichia coli was optimal in soilsrich in organic matter and under flooding According tothese authors water holding capacity which depends on
soil texture and organic matter content is known to havean impact on fecal bacteria Analyses of poultry manure ingrowing period 4 (the wettest period) revealed the influenceof humidity As soils with a high humus ratio have the highestwater holding capacity they provide a favorable environmentfor the survival of fecal pathogens In conclusion in this studyarea a large proportion of the fecal bacteria supplied by thepoultry manure did not survive due to unfavorable abioticconditions (temperature pH and organic matter content)
32 High Level of Contamination of Harvested VegetablesIndividually site fertilization treatment and type of vege-table had no significant effect on the number of fecalmicroor-ganisms (Figures 2(a) 2(b) and 2(c)) Log-transformed fecalcoliform counts on vegetables were close to 10 that is higherthan those of Escherichia coli and fecal streptococci (eachclose to six) (Figure 3)
The number of populations of microorganisms variedconsiderably among the four growing periods and among thethree vegetables crops (Figures 2(a) 2(b) and 2(c)) From 5May 2009 to 13 May 2010 (three successive growing periods)fecal coliforms increased four times on carrot (28 to 107) andalmost two times on eggplant (48 to 85) In the same periodsfecal coliforms on tomato increased almost four times (from23 to 86) but decreased by half on both vegetables in period 4(Figures 2(a) 2(b) and 2(c)) On tomato (Figure 2(c)) fecalcoliforms increased from two in period 1 to nine in period3 before decreasing to four in period 4 The highest rateof contamination by fecal coliforms (lt11) on carrot and byEscherichia coli on eggplant (7) occurred in period 3 and inperiod 2 on carrot (lt9)The number of fecal coliforms on thevegetables reached its peak in periods 2 and 3 whereas thenumber of Escherichia coli (7) was highest in period 3 andthat of fecal streptococci (gt8) was highest in period 2 Fecalcoliforms were lowest (around 2) in period 1 Escherichiacoli were absent during some growing periods and fecalstreptococci were absent in period 4 (Figure 2(b))
In the vegetable samples the mean number of fecal bac-teria per gram was considerably higher than the levelsrecommended by the French Standards Association [27] forfresh vegetables (Table 2) 8 to 10 times higher than the stand-ard for fecal coliforms 2 to 6 times higher than the standardfor Escherichia coli and 5 to 8 times higher than the standardfor fecal streptococci
Although the original source of contamination of pro-duce has seldom been identified manure from farm ani-mals has long been suspected of being a leading vehicle ofpathogen transmission Concerning the different results andthe fact that the major source of contamination of freshproducts is microbial pathogens we agree with Ijabadeniyiet al [11] who reported that at the preharvest stage thesources include feces irrigation water inadequately com-posted manure soil air animals and human handling
33 Role of Poultry Manure in the Contamination of Vegeta-bles Considering all the treatments (T0 T1 T2 and T3)together we found all three types of fecal bacteria in the threevegetable crops (Figures 2(a) 2(b) and 2(c)) As shown by theresults of the analyses of variance (Table 3) at 119901 lt 005 only
International Journal of Food Science 5
02468
101214
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f car
rot
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(a)
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f egg
plan
t
(b)
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
m co
unt
per g
of t
omat
o
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(c)
Figure 2 (a) Changes in populations of fecal bacteria on carrot per growing period (sites and fertilization treatments considered together(coastal area of Benin 2009-2010 288 plots 32 samples)) (b) Changes in populations of fecal bacteria on eggplant per growing period (sitesand fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32 samples)) (c) Changes in populations of fecalbacteria on tomato per growing period (sites and fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32samples))
Table 2 Populations of fecal coliforms Escherichia coli and fecal streptococci on each crop (sites growing periods and fertilizationtreatments considered together) in comparison to AFNOR criteria (coastal area of Benin 2009-2010 288 plots 96 samples of all crops)
Log of mean fecal bacteriacounted per g of crop
Carrot Eggplant Tomato AFNOR criteriaM SD M SD M SD
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
Table 1 Fertilization modalities at each growing period application of poultry manure and mineral fertilizers on the three tested vegetablecrops (eggplant tomato and carrot) Amendment was applied one week before sowing top-dressing was applied twice 2 weeks and 4 weeksafter sowing (coastal area of Benin 2009-2010 288 plots)
Fertilization modalities Amendment (tsdothaminus1) Total top-dressing (tsdothaminus1) Total per growing period (tsdothaminus1)T0 control 0 0 0T1 farmer practice 1
vegetables The samples were immediately placed in sterilebags A total of 96 composite samples of fresh vegetableswere analyzed for the period of 2009-2010 Eight samplesof poultry manure were collected before each sowing dateOne kg of poultry manure was collected using the proceduredescribed above All samples of poultry manure were imme-diately sealed in sterile bags at 25∘C and transported to thelaboratory
Analyses of the different samples (poultry manure andvegetables) were performed by the ldquoWater and Food QualityControl Laboratory of the Ministry of Healthrdquo in CotonouAt the time this laboratory was the only one in Cotonouto perform microbiological analyses of both liquid and solidfoods During the study period a second laboratory whichwas only qualified for microbiology analyses in water hadproblems with its specific equipment But as soils and poultrymanure are solid and the target of the present study wasfecal pathogens samples of soils and poultry manures werealso sent to that qualified laboratory In the absence ofevidence from other organizations (FAO CEE and IRD)or other European recommendations that mention levels offecal pathogens recorded in soils and manure AFNOR foodand water criteria are used in the paper To our knowl-edge the purpose of the AFNOR criteria is to identify theconcentration of these pathogens in the substances likevegetables or water consumed by human beings For thisreason we compare our data concerning soils and poultrymanure with AFNOR criteria and analytical techniques
(i) Vegetables and Poultry Manure Note the following(a) Fecal coliforms per g were identified by colimetry
using the V-08-60 RapidrsquoE coli medium (24 h at44∘C)
(b) Escherichia coli per g were identified by colimetryusing the V-08-053 RapidrsquoE coli medium (24 h at44∘C)
(c) Fecal streptococci were identified by NFT 90416 andBartley and Slanetz medium (24 hndash48 h at 37∘C)
The number of fecal microorganisms per gram of com-posite sample of fresh vegetables or of poultry manure or ofsoils was used as the unit of measure
24 Data Analysis Analysis of variance on repeated mea-sures [22] was performed to test the effects of ldquogrowingperiodrdquo ldquofertilization treatmentrdquo ldquovegetable croprdquo and ldquositerdquoon the populations of microorganisms of soils while tra-ditional analysis of variance (nonrepeated measures) wasperformed to test the effects of the above-cited factors (exceptldquogrowing periodrdquo) on the populations of fecal microorgan-isms on the vegetables In the twomodels site was consideredas random factor while the other factors were fixed Thesestatistical analyses were conducted using SAS software ver-sion 92
To stabilize the variances each of the three variables (fecalcoliforms Escherichia coli and fecal streptococci) was log-transformed according to the following relation119910 = ln(119909+1)where 119909 is the number of bacteria observed for each variableand 119910 is the result of the transformation
The adjusted means of the three variables were compiledwith the corresponding coefficients of variation Student-Newman-Keuls (SNK) tests distinguished means by high-lighting the different groups of homogenous treatments
Factors able to explain the variability of the number offecal bacteria in the study area were identified
3 Results and Discussion
31 Changes in Populations of Fecal Bacteria in the PoultryManure as a Function of the Growing Period High temporalvariability of the number of fecal bacteria in the poultrymanure at the two sites was observed (Figure 1) Log-trans-formed fecal coliform counts increased from 5May 2009 to 2September 2009 (period 1) and from 10 September 2009 to 12January 2010 (period 2) Conversely log-transformed countsof Escherichia coli decreased from 4 in period 1 to slightly lessthan 4 in period 2 and were absent from 20 January 2010 to 13May 2010 (period 3) and from 21 May 2010 to 15 August 2010(period 4) The number of streptococci decreased frommorethan 6 in period 1 to slightly less than 6 in period 2 and thenincreased to 8 in period 3 before falling to slightly less than 4in period 4
The high temperatures (30∘C to 35∘C) betweenDecember2009 and January 2010 when the poultry manure was storedoutside the henhouse probably helped reduce populations
4 International Journal of Food Science
0123456789
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
Log
of m
ean
feca
l ger
ms c
ount
per g
of p
oultr
y m
anur
e
Fecal coliformsEscherichia coliFecal streptococci
Figure 1 Changes in populations of the three fecal microorganismsin poultry manure over the four growing periods (coastal area ofBenin 2009-2010)
of fecal coliforms by more than half (growing period 2 togrowing period 3) A similar situation was observed forEscherichia coli in irrigation water and soils at both sites buthere we rather witnessed their disappearance from period1 (harvest period) to period 3 However concerning thepoultry manure the untimely actions of the driving rainduring the trial could explain the variations that occurred inperiod 4 when the poultry manure was stored outside thehenhouse for two months (from April 2010 to May 2010)Rainfall amounted to 147mm in eight days from 1 April 2010to 12 April 2010 versus 16 days for the same volume duringthe same period in 2009 Driving rains could thus also havebeen responsible for the reduction in (or the absence of)microorganisms at some dates in particular Escherichia coliand fecal streptococci in the poultry manure taken from thehenhouse on 10 April 2010 and analyzed on 13 May 2010Thisobservation is in accordance with the results of Hutchisonet al [23] who contrasted the effect of driving rain on thesurvival of fecal coliforms causing their destruction andwashing them out with the effect of drizzle Like Jamieson etal [24] our results showed that bacterial survival was optimalin cold wet conditions But it is possible that competitionamong microorganisms also affects the survival of fecalbacteria in the soil in line with the influence of predation[25] In the study area predation among bacteria could alsobe responsible for the disappearance of fecal pathogens
Based on the results observed through Figure 1 it ispossible to conclude that because there was no organicmatter in the soil as soon as the poultry manure was appliedto the soil the fecal microorganisms remained on the surfaceand moved directly towards the vegetables Franz et al [26]reported that survival of Escherichia coli was optimal in soilsrich in organic matter and under flooding According tothese authors water holding capacity which depends on
soil texture and organic matter content is known to havean impact on fecal bacteria Analyses of poultry manure ingrowing period 4 (the wettest period) revealed the influenceof humidity As soils with a high humus ratio have the highestwater holding capacity they provide a favorable environmentfor the survival of fecal pathogens In conclusion in this studyarea a large proportion of the fecal bacteria supplied by thepoultry manure did not survive due to unfavorable abioticconditions (temperature pH and organic matter content)
32 High Level of Contamination of Harvested VegetablesIndividually site fertilization treatment and type of vege-table had no significant effect on the number of fecalmicroor-ganisms (Figures 2(a) 2(b) and 2(c)) Log-transformed fecalcoliform counts on vegetables were close to 10 that is higherthan those of Escherichia coli and fecal streptococci (eachclose to six) (Figure 3)
The number of populations of microorganisms variedconsiderably among the four growing periods and among thethree vegetables crops (Figures 2(a) 2(b) and 2(c)) From 5May 2009 to 13 May 2010 (three successive growing periods)fecal coliforms increased four times on carrot (28 to 107) andalmost two times on eggplant (48 to 85) In the same periodsfecal coliforms on tomato increased almost four times (from23 to 86) but decreased by half on both vegetables in period 4(Figures 2(a) 2(b) and 2(c)) On tomato (Figure 2(c)) fecalcoliforms increased from two in period 1 to nine in period3 before decreasing to four in period 4 The highest rateof contamination by fecal coliforms (lt11) on carrot and byEscherichia coli on eggplant (7) occurred in period 3 and inperiod 2 on carrot (lt9)The number of fecal coliforms on thevegetables reached its peak in periods 2 and 3 whereas thenumber of Escherichia coli (7) was highest in period 3 andthat of fecal streptococci (gt8) was highest in period 2 Fecalcoliforms were lowest (around 2) in period 1 Escherichiacoli were absent during some growing periods and fecalstreptococci were absent in period 4 (Figure 2(b))
In the vegetable samples the mean number of fecal bac-teria per gram was considerably higher than the levelsrecommended by the French Standards Association [27] forfresh vegetables (Table 2) 8 to 10 times higher than the stand-ard for fecal coliforms 2 to 6 times higher than the standardfor Escherichia coli and 5 to 8 times higher than the standardfor fecal streptococci
Although the original source of contamination of pro-duce has seldom been identified manure from farm ani-mals has long been suspected of being a leading vehicle ofpathogen transmission Concerning the different results andthe fact that the major source of contamination of freshproducts is microbial pathogens we agree with Ijabadeniyiet al [11] who reported that at the preharvest stage thesources include feces irrigation water inadequately com-posted manure soil air animals and human handling
33 Role of Poultry Manure in the Contamination of Vegeta-bles Considering all the treatments (T0 T1 T2 and T3)together we found all three types of fecal bacteria in the threevegetable crops (Figures 2(a) 2(b) and 2(c)) As shown by theresults of the analyses of variance (Table 3) at 119901 lt 005 only
International Journal of Food Science 5
02468
101214
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f car
rot
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(a)
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f egg
plan
t
(b)
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
m co
unt
per g
of t
omat
o
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(c)
Figure 2 (a) Changes in populations of fecal bacteria on carrot per growing period (sites and fertilization treatments considered together(coastal area of Benin 2009-2010 288 plots 32 samples)) (b) Changes in populations of fecal bacteria on eggplant per growing period (sitesand fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32 samples)) (c) Changes in populations of fecalbacteria on tomato per growing period (sites and fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32samples))
Table 2 Populations of fecal coliforms Escherichia coli and fecal streptococci on each crop (sites growing periods and fertilizationtreatments considered together) in comparison to AFNOR criteria (coastal area of Benin 2009-2010 288 plots 96 samples of all crops)
Log of mean fecal bacteriacounted per g of crop
Carrot Eggplant Tomato AFNOR criteriaM SD M SD M SD
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
Figure 1 Changes in populations of the three fecal microorganismsin poultry manure over the four growing periods (coastal area ofBenin 2009-2010)
of fecal coliforms by more than half (growing period 2 togrowing period 3) A similar situation was observed forEscherichia coli in irrigation water and soils at both sites buthere we rather witnessed their disappearance from period1 (harvest period) to period 3 However concerning thepoultry manure the untimely actions of the driving rainduring the trial could explain the variations that occurred inperiod 4 when the poultry manure was stored outside thehenhouse for two months (from April 2010 to May 2010)Rainfall amounted to 147mm in eight days from 1 April 2010to 12 April 2010 versus 16 days for the same volume duringthe same period in 2009 Driving rains could thus also havebeen responsible for the reduction in (or the absence of)microorganisms at some dates in particular Escherichia coliand fecal streptococci in the poultry manure taken from thehenhouse on 10 April 2010 and analyzed on 13 May 2010Thisobservation is in accordance with the results of Hutchisonet al [23] who contrasted the effect of driving rain on thesurvival of fecal coliforms causing their destruction andwashing them out with the effect of drizzle Like Jamieson etal [24] our results showed that bacterial survival was optimalin cold wet conditions But it is possible that competitionamong microorganisms also affects the survival of fecalbacteria in the soil in line with the influence of predation[25] In the study area predation among bacteria could alsobe responsible for the disappearance of fecal pathogens
Based on the results observed through Figure 1 it ispossible to conclude that because there was no organicmatter in the soil as soon as the poultry manure was appliedto the soil the fecal microorganisms remained on the surfaceand moved directly towards the vegetables Franz et al [26]reported that survival of Escherichia coli was optimal in soilsrich in organic matter and under flooding According tothese authors water holding capacity which depends on
soil texture and organic matter content is known to havean impact on fecal bacteria Analyses of poultry manure ingrowing period 4 (the wettest period) revealed the influenceof humidity As soils with a high humus ratio have the highestwater holding capacity they provide a favorable environmentfor the survival of fecal pathogens In conclusion in this studyarea a large proportion of the fecal bacteria supplied by thepoultry manure did not survive due to unfavorable abioticconditions (temperature pH and organic matter content)
32 High Level of Contamination of Harvested VegetablesIndividually site fertilization treatment and type of vege-table had no significant effect on the number of fecalmicroor-ganisms (Figures 2(a) 2(b) and 2(c)) Log-transformed fecalcoliform counts on vegetables were close to 10 that is higherthan those of Escherichia coli and fecal streptococci (eachclose to six) (Figure 3)
The number of populations of microorganisms variedconsiderably among the four growing periods and among thethree vegetables crops (Figures 2(a) 2(b) and 2(c)) From 5May 2009 to 13 May 2010 (three successive growing periods)fecal coliforms increased four times on carrot (28 to 107) andalmost two times on eggplant (48 to 85) In the same periodsfecal coliforms on tomato increased almost four times (from23 to 86) but decreased by half on both vegetables in period 4(Figures 2(a) 2(b) and 2(c)) On tomato (Figure 2(c)) fecalcoliforms increased from two in period 1 to nine in period3 before decreasing to four in period 4 The highest rateof contamination by fecal coliforms (lt11) on carrot and byEscherichia coli on eggplant (7) occurred in period 3 and inperiod 2 on carrot (lt9)The number of fecal coliforms on thevegetables reached its peak in periods 2 and 3 whereas thenumber of Escherichia coli (7) was highest in period 3 andthat of fecal streptococci (gt8) was highest in period 2 Fecalcoliforms were lowest (around 2) in period 1 Escherichiacoli were absent during some growing periods and fecalstreptococci were absent in period 4 (Figure 2(b))
In the vegetable samples the mean number of fecal bac-teria per gram was considerably higher than the levelsrecommended by the French Standards Association [27] forfresh vegetables (Table 2) 8 to 10 times higher than the stand-ard for fecal coliforms 2 to 6 times higher than the standardfor Escherichia coli and 5 to 8 times higher than the standardfor fecal streptococci
Although the original source of contamination of pro-duce has seldom been identified manure from farm ani-mals has long been suspected of being a leading vehicle ofpathogen transmission Concerning the different results andthe fact that the major source of contamination of freshproducts is microbial pathogens we agree with Ijabadeniyiet al [11] who reported that at the preharvest stage thesources include feces irrigation water inadequately com-posted manure soil air animals and human handling
33 Role of Poultry Manure in the Contamination of Vegeta-bles Considering all the treatments (T0 T1 T2 and T3)together we found all three types of fecal bacteria in the threevegetable crops (Figures 2(a) 2(b) and 2(c)) As shown by theresults of the analyses of variance (Table 3) at 119901 lt 005 only
International Journal of Food Science 5
02468
101214
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f car
rot
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(a)
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
ms
coun
t per
g o
f egg
plan
t
(b)
0
2
4
6
8
10
12
Log
of m
ean
feca
l ger
m co
unt
per g
of t
omat
o
Fecal coliformsEscherichia coliFecal streptococci
5 M
ay 2
009
to2
Sept
embe
r 200
9
10 S
epte
mbe
r 200
9 to
12 Ja
nuar
y 20
10
20 Ja
nuar
y 20
10 to
13 M
ay 2
010
21 M
ay 2
010
to15
Aug
ust 2
010
(c)
Figure 2 (a) Changes in populations of fecal bacteria on carrot per growing period (sites and fertilization treatments considered together(coastal area of Benin 2009-2010 288 plots 32 samples)) (b) Changes in populations of fecal bacteria on eggplant per growing period (sitesand fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32 samples)) (c) Changes in populations of fecalbacteria on tomato per growing period (sites and fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32samples))
Table 2 Populations of fecal coliforms Escherichia coli and fecal streptococci on each crop (sites growing periods and fertilizationtreatments considered together) in comparison to AFNOR criteria (coastal area of Benin 2009-2010 288 plots 96 samples of all crops)
Log of mean fecal bacteriacounted per g of crop
Carrot Eggplant Tomato AFNOR criteriaM SD M SD M SD
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
Figure 2 (a) Changes in populations of fecal bacteria on carrot per growing period (sites and fertilization treatments considered together(coastal area of Benin 2009-2010 288 plots 32 samples)) (b) Changes in populations of fecal bacteria on eggplant per growing period (sitesand fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32 samples)) (c) Changes in populations of fecalbacteria on tomato per growing period (sites and fertilization treatments considered together (coastal area of Benin 2009-2010 288 plots 32samples))
Table 2 Populations of fecal coliforms Escherichia coli and fecal streptococci on each crop (sites growing periods and fertilizationtreatments considered together) in comparison to AFNOR criteria (coastal area of Benin 2009-2010 288 plots 96 samples of all crops)
Log of mean fecal bacteriacounted per g of crop
Carrot Eggplant Tomato AFNOR criteriaM SD M SD M SD
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
Table 3 Analysis of variance onrepeated measures Fisher values illustrating the effects of growing period fertilization modality vegetablecrop and site on the fecal bacteria populations in vegetables (coastal area of Benin 2009-2010 288 plots)
Figure 3 Populations of fecal coliforms Escherichia coli andfecal streptococci on vegetables (sites growing periods fertilizationtreatments and vegetables considered together (coastal area ofBenin 2009-2010 288 plots 96 samples))
the growing period had a significant effect (probability 01)on the concentrations of the three fecal bacteria analyzedTheapplication of fertilizer had no significant impact on the highinitial contamination of the environment For instance thecontrol treatment (T0) that is no poultry manure resultedin as high level of fecal coliforms as treatments T1 (mineralfertilizer) T2 (mineral fertilizer + poultry manure) andT3 (manure only) on all three vegetables (Figure 4) Werecorded log-transformed average counts of eight for fecalcoliforms in the plots with the control treatment T0 six forEscherichia coli and three for fecal streptococci
On the other hand treatments T2 and T3 tended toresult in more fecal coliforms and fecal streptococci in all thegrowing periodsThis tendency was most marked in period 2in the short rainy season and in period 3 during the long dryseason (Figures 1 2(a) 2(b) and 2(c))
The control treatment (T0) under which no poultrymanure was applied resulted in the same high concentrationof fecal microorganisms in all three vegetables as treatmentsT1 T2 and T3This is likely due to the untimely actions of theflow of irrigation water and rain on the plots under controltreatment T0 The long traditional use of poultry manurewhich probably left fecal bacteria in the soil and water in
0
2
4
6
8
10
12
14
T0 T1 T2 T3
Log
of m
ean
feca
l ger
ms c
ount
per g
of v
eget
able
Fecal coliformsEscherichia coliFecal streptococci
Figure 4 Populations of the three fecal bacteria per fertilizationtreatment T0 unfertilized control T1 mineral fertilization (urea+ NPK) T2 mineral fertilization + 10 tsdothaminus1 of poultry manureand T3 40 tsdothaminus1 of poultry manure (coastal area of Benin 2009-2010 288 plots) The fertilization with or without poultry manurehad no significant impact on the high initial contamination of theenvironment
the study area before the beginning of the trials is anotherprobable explanation
On the other hand the lower number of Escherichiacoli in all three vegetables with treatment T3 confirmedthat contamination was recent Even though three monthspassed between application of the fertilizer and harvest it ishighly probable that Escherichia coli we counted came fromthe applied poultry manure So in the case of Grand-Popoboth traditional organic fertilizers (poultry manure and cowdung) and the poultry manure supplied during the trial canbe assumed to be responsible for the contamination Ourresults are in agreement with those of Amponsah-Doku etal [9] who reported that poultry manure which is the mainfertilizer used by 75 of lettuce growers in Accra and Kumasi(Ghana) was responsible for the contamination of the lettuceby numerous fecal coliforms
Urban areas can also be sources of fecal pollution stormwaters can transport fecal organisms in runoff originatingfrom domestic waste urban wildlife or domestic animalsThe many heaps of wastes observed in the villages of Ayi-Guinnou and Yodo-Condji and the liquid wastes deposited in
International Journal of Food Science 7
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
the environment along with vegetable leftovers were possiblesources of contamination Moreover for more than 70 ofthe local population river banks and the beach are defecationareas with deleterious consequences for the microbiologicalquality of the irrigation water which is also used as drinkingwater by the local population [1 28]
4 Conclusion
Application of contaminated poultry manure to the cropsin gardening sites may result in contamination of vegetablesby the following fecal bacteria fecal coliforms Escherichiacoli and fecal streptococci Our study has demonstrated thatthe use of poultry manure as fertilizer during the agronomictrials has influenced the fecal bacteria counts recorded on thevegetables The long traditional use of poultry manure whichprobably left fecal bacteria in the soil and water in the studyarea before the beginning of the trials is another probableexplanation
This statement of the environment constitutes a genuinedanger for the public health that of the farmers localpopulations and the consumers of the vegetables produced inthe area The combination of market gardening and livestockrising is widely considered to be a good way to increase plantyields But our results show that it can also have negativeimpacts on human health For this reason to achieve sustain-able urban agriculture in Africa those designing innovativecropping systems need to be mindful of the environmentand of public health concerns and such systems should bedeveloped through multidisciplinary research that includesmoremedical biological environmental and socioeconomiccomponents But in the immediate future the use of properlycomposted poultry manure should help reduce the numberand range of pathogens and hence avoid the application ofcontaminated manure
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
Acknowledgments
The current study was conducted with the financial supportof Hydraulic and Water Control Laboratory of the Facultyof Agronomic Science of Abomey-Calavi University throughProject BEN145-UACFSA The authors thank Cecile Fovet-Rabot very much for her comments and corrections made tothe paper
References
[1] H De Bon L Parrot and P Moustier ldquoSustainable urbanagriculture in developing countries A reviewrdquo Agronomy forSustainable Development vol 30 no 1 pp 21ndash32 2010
[2] M Lydecker and P Drechsel ldquoUrban agriculture and sanitationservices in Accra Ghana the overlooked contributionrdquo Inter-national Journal of Agricultural Sustainability vol 8 no 1-2 pp94ndash103 2010
[3] D J Midmore and H G P Jansen ldquoSupplying vegetables toAsian cities is there a case for Peri-urban productionrdquo FoodPolicy vol 28 no 1 pp 13ndash27 2003
[4] OCofieV RVeenhuizenV deVreede and SMaessen ldquoWasteManagement for Nutrient Recovery options and challenges forurban agriculturerdquoUrban AgricultureMagazine vol 23 pp 3ndash72010
[5] P Drechsel and S Dongus ldquoDynamics and sustainability ofurban agriculture examples from sub-Saharan Africardquo Sustain-ability Science vol 5 no 1 pp 69ndash78 2010
[6] S Atidegla Effets des differentes doses drsquoengrais mineraux et dela fiente de volaille sur lrsquoaccumulation de biocontaminants etpolluants (germes fecaux composes azotes et phosphores metauxlourds) dans les eaux les sols et les legumes de Grand-Popo auBenin [PhD thesis] EDPFLASH Universite drsquoAbomey-Calavi(UAC) Benin West Africa 2011
[7] M Delgado C Rodrıguez J V Martın R Miralles de Imperialand F Alonso ldquoEnvironmental assay on the effect of poultrymanure application on soil organisms in agroecosystemsrdquoScience of the Total Environment vol 416 pp 532ndash535 2012
[8] J P Brooks A Adeli M R Mclaughlin and D M Miles ldquoTheeffect of poultry manure application rate and AlCl3 treatmenton bacterial fecal indicators in runoffrdquo Journal of Water andHealth vol 10 no 4 pp 619ndash628 2012
[9] F Amponsah-Doku K Obiri-Danso R C Abaidoo L AAndoh P Drechsel and F Kondrasen ldquoBacterial contamina-tion of lettuce and associated risk factors at production sitesmarkets and street food restaurants in urban and peri-urbanKumasi Ghanardquo Scientific Research and Essays vol 5 no 2 pp217ndash223 2010
[10] Centers for Disease Control and Prevention (CDCP) ldquoOut-breaks of Escherichia coli O157 H7 infections among childrenassociated with farms visitsmdashPennsylvania and WashingtonrdquoMorbidity and Mortality Weekly Report vol 50 no 15 pp 293ndash297 2001
[11] O A Ijabadeniyi L K Debusho M Vanderlinde and EM Buys ldquoIrrigation water as a potential preharvest source ofbacterial contamination of vegetablesrdquo Journal of Food Safetyvol 31 no 4 pp 452ndash461 2011
[12] T Garcia-Armisen and P Servais ldquoRespective contributions ofpoint and non-point sources of E coli and enterococci in alarge urbanized watershed (the Seine river France)rdquo Journal ofEnvironmental Management vol 82 no 4 pp 512ndash518 2007
[13] M J Pantshwa A M van der Walt S S Cilliers and C CBezuidenhout ldquoInvestigation of faecal pollution and occur-rence of antibiotic resistant bacteria in the Mooi river system asa function of a changed environmentrdquo 2009 httpwwwewisacozaliteraturefiles2008 137pdf
[14] D L Swerdlow B AWoodruff R C Brady et al ldquoAwaterborneoutbreak in Missouri of Escherichia coli O157H7 associatedwith bloody diarrhea and deathrdquo Annals of Internal Medicinevol 117 no 10 pp 812ndash819 1992
[15] M P Griffin S M Ostroff R V Tauxe et al ldquoIllnesses asso-ciated with Escherichia coliO157 H7 infections a broad clinicalspectrumrdquo Annals of Internal Medicine vol 109 no 9 pp 705ndash712 1988
[16] K Ibenyassine R AitMhand Y Karamoko N Cohen and MM Ennaji ldquoUse of repetitive DNA sequences to determine thepersistence of enteropathogenic Escherichia coli in vegetablesand in soil grown in fields treated with contaminated irrigationwaterrdquo Letters in Applied Microbiology vol 43 no 5 pp 528ndash533 2006
8 International Journal of Food Science
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
[17] M Steele A Mahdi and J Odumeru ldquoMicrobial assessment ofirrigation water used for production of fruit and vegetables inOntario Canadardquo Journal of Food Protection vol 68 no 7 pp1388ndash1392 2005
[18] M Makoutode A K Assani E M Ouendo V D Aguehand P Diall ldquoQualite et mode degestion de lrsquoeau de puits enmilieu rural au Benin cas de la sous-prefecture de Grand PopordquoMedecine drsquoAfrique Noire vol 46 pp 528ndash534 1999
[19] Y H B Nguendo G Salem and J Thouez ldquoRisques sanitaireslies aux modes drsquoassainissement des excreta a Yaounde Camer-ounrdquoNatural Science and Sociology vol 16 no 1 pp 3ndash12 2008
[20] P Turgeon P Michel P Levallois M Archambault and ARavel ldquoFecal contamination of recreational freshwaters theeffect of time-independent Agroenvironmental factorsrdquo WaterQuality Exposure and Health vol 3 no 2 pp 109ndash118 2011
[21] A Abdulkadir L H Dossa D J-P Lompo N Abdu and Hvan Keulen ldquoCharacterization of urban and peri-urban agro-ecosystems in three West African citiesrdquo International Journalof Agricultural Sustainability vol 10 no 4 pp 289ndash314 2012
[22] M J Crowder and D J Hand Analysis of Repeated MeasuresChapman and Hall New York NY USA 1990
[23] M L Hutchison L DWalters AMoore KM Crookes and SM Avery ldquoEffect of length of time before incorporation on sur-vival of pathogenic bacteria present in livestock wastes appliedto agricultural soilrdquo Applied and Environmental Microbiologyvol 70 no 9 pp 5111ndash5118 2004
[24] R C Jamieson R J Gordon K E Sharples G W Strattonand A Madani ldquoMovement and persistence of fecal bacteriain agricultural soils and subsurface drainage water a reviewrdquoCanadian Biosystems Engineering vol 44 pp 1ndash9 2002
[25] K R Reddy R Khaleel and M R Overcash ldquoBehavior andtransport of microbial pathogens and indicator organisms insoils treated with organic wastesrdquo Journal of EnvironmentalQuality vol 10 no 3 pp 255ndash266 1981
[26] E Franz A V Semenov A J Termorshuizen O J de Vos JG Bokhorst and A H C van Bruggen ldquoManure-amended soilcharacteristics affecting the survival of E coli O157H7 in 36Dutch soilsrdquo Environmental Microbiology vol 10 no 2 pp 313ndash327 2008
[27] AFNOR (Association Francaise de Normalisation) Diction-naire de Lrsquoenvironnement de lrsquoAssociation Francaise de Normal-isation Les Termes Normalises AFNOR (Association Francaisede Normalisation) Paris France 1994
[28] C Atidegla and K Agbossou ldquoPollutions chimique et bac-teriologique des eaux souterraines des exploitations maraı-cheres irriguees de la commune deGrand-Popo cas des nitrateset bacteries fecalesrdquo International Journal of Biological andChemical Sciences vol 4 no 2 pp 327ndash337 2010
![Fecal contamination and related health effects at a ... contamination and related health effects at a ... Aeromonas hydrophila Aeromonas hydrophila ... Ewers 125.ppt [Read-Only]](https://static.documents.pub/doc/80x56/5ada57817f8b9aee348ca8a5/fecal-contamination-and-related-health-effects-at-a-contamination-and-related.jpg)
