Appendix 5

Shin-ichi Sakai

Substance Flow Approach for Regionally Based Assessment of POPs

Human-Activity-Based Sourcesof POPs

Intentionally produced substances for commercial activities of industry, agriculture and medicine-- PCBs, PCP, DDT, Aldrin, Dieldrin, Endrin, HCH, etc.

Unintentionally produced by-products during chemical and combustive reactions-- PCDDs/DFs, Co-PCBs, etc.

Three Backgrounds of POPs

1. There are two types: intentional products and unintentional by- products.

2. They widely range from regional level to global level.

3. There is a time lag between emission, transport and accumulation.

Regionally Based Assessment of POPs- Material Flow Approach

1. Inventory of each POPs source in the regional environment, paying attention to air, soil and water phase

2. Input/Output analysis to understand which processes destroy or produce POPs for products and waste circulating in various industrial and social sectors as a material chain

3. Time trend analysis using soil or sediment core to evaluate accumulativeness and persistency

Source Inventory of PCDDs/DFs in JapanInventory issued by MITI in November 1998

Total emission into air: 5,300 g-TEQ/yrMSW incineration: 80%Steel manufacturing (electric furnace):

190 g-TEQ/yr, 3.5%Steel manufacturing (sintering):

119 g-TEQ/yr, 2.2%Zinc recovery: 34 g-TEQ/yr, 0.6%Aluminum alloy manufacturing:

16 g-TEQ/yr, 0.3%

Inventory issued by MHW in September 1998Emission from MSW incineration with high PCDDs/DFs concentration was reduced from 1,338 g-TEQ/yr in 1997 to 94 g-TEQ/yr in 1998.

Material ChainTaking zinc recovery processes as an example,

- Zinc is recovered from fly ash containing PCDDs/DFs from steel manufacturing of scrap metals.

- PCDDs/DFs contained in fly ash are mostly decomposed in the refining process of zinc recovery.(Approx. 70% of PCDDs/DFs are decomposed.)

PCDDs/DFs, not destroyed during the refining process and formed during the waste gas treatment process, amount to 34 g-TEQ/yr.

It is important to understand the industrial chain of these materials in controlling PCDDs/DFs is important.

An Example of Regional Water System

Lake Biwa

- Largest lake in Japan- Surface area: 685 km2

- Volume: 27.5 m3

- North-south longest length: 63 km- East-west longest length: 23 km- Maximum depth: 104 m- Average depth: 41 m

Catchment area of Lake Biwa is 3,848 km2, 53% of the total basin of the Yodo river, where 120 rivers start from mountains in Shiga prefecture flow together.

An Example of Regional Water System

The Yodo river- Length of the main river: 75.1 km- Average flow volume: 200 m3/sec- 70% of the volume originates from Lake Biwa.- It runs through 5 prefectures, Osaka, Kyoto,

Hyogo, Shiga and Mie.- Size of the basin: 7,281 km2, 35% of the area of the Kinki region

A source of drinking water for 14 mio people in the Kinki districtUse for agricultural and industrial activities

An Example of Regional Water SystemOsaka Bay

- Elliptic Inland Sea- Location: Eastern part of the Seto Inland Sea- Long axis: 60 km- Short axis: 30 km- Surface area: 1,400 km2

- Average depth: 28 m

Osaka Bay leads to the ocean through the Tomogashima Channel and leads to the Sea of Harima through the Akashi Strait.The main current runs through the Tomogashima Channel and the Akashi Strait taking the route from the center of the bay toward the western side.The water from the land, pours into the bay from inner part of the bay, flows toward the mouth of the bay along the eastern side.

PCBs Concentration Level in the Water System of Lake Biwa and Osaka Bay

Investigation

Fukushima et al. traced the PCBs concentrations in the water system of Lake Biwa, the Yodo River and Osaka Bay in order to judge the effect of the PCBs regulation and to clarify the PCBs transport in the water environment.

PCBs Concentration Level in the Water System

Results

Before the regulation:Level in the surface stream was high in vigorously productive and consumptive areas.

After the regulation:Level in rivers running through Osaka City lowered: 0.18 µg/ 0.02 µg/ Level in rivers flowing into the Yodo River lowered: 0.07 µg/ 0.01 µg/ Level in the main course of the Yodo River retained 0.01 µg/.Level in the surface water of the coastal area

of Osaka Bay: 0.05 µg/ 0.01 µg/

PCBs Concentration Level in the Water System

Conclusion

Except for inconsistencies before and after 1978, the PCBs levels in the surface water and the sediment are proportional.

PCBs in the surface water of the coast and the mouth of the river are removed by the settling of suspended particles.

PCBs removed with particles is piled up as sediment.

The settled PCBs with particles determines the PCBs level in the surface layer of the sediment.

Material Flow Analysis

To manage organic substances which are formed and decomposed in society, such as PCDDs/DFs, the material flow concept is more important than material balance.

Through the input/output analysis from each source to various environmental media, we can understand the appropriate control and monitoring points.

Co-PCBs

Co-PCBs can be classified into two groups according to their sources:

1. CO-PCBs contained in PCBs products manufactured in the past

Approx. 60,000 tons of PCBs were produced by 1972 in Japan.

Approx. 50,000 tons of PCBs are assumed to still be in use or stock in industrial

facilities.

2. Co-PCBs formed as by-products of various incineration processes

Co-PCBs Formationin Incineration Processes

Percentages of Co-PCBs in all PCBs detected in emission gas and fly ash: 5~10%

Compared to Co-PCBs in PCB products which account for 1%, the percentage of Co-PCBs in all PCBs formed in the incineration process is higher.

Contribution rate of Co-PCBs to the TEQ-concentration of PCDDs/DFs: 2~4%* Only 3 kinds of non-ortho Co-PCBs (#77, #126 and #169) were measured.

Co-PCBs in Different Compositions of MSW

Concentration of #118 (2,3’,4,4’,5-P5CB) was high.

Concentrations of #105 (2,3,3’,4,4’-P5CB) and #77 (3,3’,4,4’-T4CB) were also relatively high.

Congener profiles of Co-PCBs in MSW compositions and atmosphere were completely different from those in emission gas and fly ash from MSW incineration facilities.

Input Amount per waste-ton (wet basis)

PCBs: 13,000 ~ 33,000 µg/waste-ton

Co-PCBs: 450 ~ 550 µg/waste-ton,0.13 ~ 0.29 µg-TEQ/waste-ton

PCDDs/DFs: 1.2 µg-TEQ/waste-ton

Contribution rate of Co-PCBs : 19%

Total Values of PCBs and Co-PCBs Released from MSW Incinerators

Results:

Total TEQ-based amount of Co-PCBs:2.8 µg-TEQ/waste-ton(> the input amount of 0.29 µg-TEQ/waste-ton)

Total input amount of PCBs:13,000 ~ 33,000 µg/waste-ton

Total output amount: 1,000 µg/waste-tonOver 90% of PCBs were decomposed.

Conclusion:

TEQ-based Co-PCBs are formed in the incineration process but Co-PCBs and PCBs as a total are decomposed.

Input/Output Amount ofeach Co-PCBs Congener

#126 and #169 of non-ortho Co-PCBs increased 10 to 50 times in the incineration processes.

These Co-PCBs contribute to the raise in the total TEQ-based output amount.

#105, #114 and #118 were decomposed at the rate of over 90%.

Non-ortho Co-PCBs are selectively formed in the incineration process.

Input/Output Amount of Dioxins (PCDDs/DFs + Co-PCBs)

Total dioxins (PCDDs/DFs + Co-PCBs)Input amount (TEQ): 1.5 µg/waste-tonOutput amount (TEQ): 160~220 µg/waste-ton

Co-PCBsPercentage in the total TEQ input: 19%Percentage in the total TEQ output: 2.2~3.1%

In emission from MSW Incineration:Co-PCBs (TEQ) < PCDDs/DFs (TEQ)

In environmental and living samples including food: Co-PCBs (TEQ) > PCDDs/DFs (TEQ)

Possible reasons:Bioaccumulation of Co-PCBs is high.Main source of PCBs is PCB products in the

environment and not incineration facilities

Future Challenges

Environmental monitoring, discussion of measures and risk assessment have to be comprehensively carried out to evaluate POPs at a regional level.

It is urgent to establish the long-term monitoring system for some environmental media, which are decisive in determining effective measures and in reviewing the measures.

Vegetables

Milk Products

Meat

Fish

Others(Drinking water Respiration)

ExposureInventory

Sourc

e Invento

ryA

ir M

edia

Sourc

e Invento

rySoil

Media

Sourc

e Invento

ryW

ate

r M

edia

Deposition

ResiduesSecondary Materials

Fig.2 Substance Flow Approach for Persistent Chemicals

Input/OutputAnalysis

By-productsMaterial Works(Fe)

Sources　 Environment Human

①Input/OutputAnalysis

By-products Gas Phase

Particle Phase

Particle Phase

PCP

Products

PBDETBBP-A

Products

PCBs

Products

Birds

Eco-System

Fish

Eco-System

②Historical Trends(Accumulation)

Soil

Sediment

Dissolved Phase

Animals

Eco-System

0

2

4

6

PCDD

/DFs

[ng/

g]Input/Output

Analysis

By-productsMaterial Works(Cu)

Pesticides

Products

③Environmental 　 Behavior Model

Plants

Eco-System

Fig.4 PCBs in Surface Water and Sediment of Osaka Bay-Yearly Average between 1974 and 1993

0

1

2

3

4

5

0

0.01

0.02

0.03

0.04

0.05

0.06

Con

cent

rati

on(µ

g/g

dry

basi

s)

Year

Concentration(µ

g/l)

1974 78 82 86 90 93

Surface Water

Sediment