persistent manufactured chemicals for non-pesticide applications and persistent by-products of...

Persistent manufactured chemicals for non-pesticide applications and

persistent by-products of industrial and combustion process

in China and Hong Kong

Ming H. WongHong Kong Baptist University

GEF PDF-B Workshop, Jan 1999

Table of contents

1. General background of China and Hong Kong.2. The use of persistent organics in China and Hong Kong.3. Case study – PCBs, PCDDs and PCDFs in China.4. PAHs in China.5. Total PCBs, PCDDs, PCDFs and PAHs in abiotic and biotic samples from China, Taiwan and Hong Kong.6. Case study – PCBs and PAHs in Hong Kong.7. Polycyclic aromatic hydrocarbons in water and sediment of

South China River.8. PCBs in freshwater fish and sediments collected from the

Pearl River Delta and Hong Kong.9. Induction of Cytochrome P4501A1 gene expression in Tilapia exposed to coastal sediment.10. General conclusion.

1. General background of China and Hong Kong

Climate- Subtropical, with cool dry winters and hot wet summers.- Rainfall occurs predominantly in the summer, coinciding with the highest air temperatures.

Population- The Pearl River delta, with an area of 23270 km2 (Ma, 1994) and a population of 15 million (Chan, 1995).- Hong Kong with an area of 1,067 km2 and a population of over 6 million.

Industrialization- Since the implementation of the economic reform and open door policy in 1978, the provinces of the South China take the lead.- Organic discharge from the industries textile, plastic, printing, dying, tannery, food, electroplating and paper production.- Heavy industrial activities and residential population close to Victoria

Harbour, but also in the developing New Towns.

Pollution- Environmental policy and legislation in China are neither strict nor effectively enforced.- Pollutants from Guangzhou and Shenzhen are washed into Hong Kong’s

estuarine waters.- The quality of drinking water and local food supplies are affected. - 2,000 major industrial factories and an estimated 200,000 smaller ones in Hong

Kong. - In Hong Kong, agricultural pollution from New Territories is due to rearing of

pigs and poultry, the populations of which are currently estimated to be 0.7 million and 7.5 million, respectively.

- Hong Kong produces about 24,000 tonnes of solid wastes per day (HKEPD, 1995).

- Since 3.5 million people and a large proportion of the industrial base are concentrated around Victoria Harbour of Hong Kong. Sewage and industrial effluents from these sources enter Victoria Harbour with little treatment (Connell et al, 1998).

- In Hong Kong, over 25% of the land in the urban area has been gained from reclamation (Morton, 1989). The reduction in water area due to reclamation has reduced the tidal flushing of both Victoria and Tolo Harbours, and exacerbated the problems of pollution due to sewage discharges.

Table 1a. Manufactured persistent organic chemicals in China: Heat Stabilizer

Use Example Chemical Group Use & Description

Major

Manufacturer

Location

Heat

Dibasic Lead

Phthalate

Phthalate - electric resistant for

PVC

- heat and light

stabilizer for plastic

Shanghai

Stabilizer Pentachlorobiphenyl PCBs - heat resistant for

plastic

- flame retardant and

plasticizer

Shanghai

2. The use of persistent organics in China and Hong Kong

Table 1b. Manufactured persistent organic chemicals in China: Plasticizer


Major

Manufacturer Location

Dimethyl

Phthalate (DMP)

Phthalate - plasticizer Shanghai, Hunan

Diisooctyl

Phthalate (DOP)

Phthalate - plasticizer for plastic, paint and

rubber

widely distributed in

China

Plasticizer

Butyl Benzyl

Phthalate

Phthalate - plasticizer for PVC & rubber and

use with other plasticizer

Jiangsu, Zhejiang

Chlorinated

Paraffin-42

Polychlorinated

Paraffin

- plasticizer for PVC

- additive for paint and lubricant oil

Shanghai, Guangzhou

Chlorinated

Paraffin-52

Polychlorinated

Paraffin

- plasticizer for PVC

- additive for paint and lubricant oil

Shanghai, Guangzhou

Diisoctyl m-

Phthalate

Phthalate - plasticizer

- substitute for DOP

Tianjian

Table 1c. Manufactured persistent organic chemicals in China: Flame Retardant


Major

Manufacturer Location

Decabromo Diphenyl

Ether (FR-10)

Polybromo

Diphenyl

- flame retardant for PVC,

nylon, etc

Jiangsu, Tianjian,

Shangdong, Shanghai

Decabromodiphenyl Oxide Polybromo

Diphenyl

- flame retardant for plastic Jiangsu

Tetrabromo Bisphenol A Polybromo Phenol - flame retardant for

plastic, rubber

Tianjian, Zhejiang,

Shanghai

Tetrabromo Bisphenol A

Allyl Ether

Polybromo Phenol - flame retardant for

plastic, rubber

Shangdong, Shanghai,

Beijing

Flame

Retardant

1, 2 - Bis (2, 4, 6-Tribomo

Phenoxy) Ethane (FR-3B)

Polybromo Phenol - flame retardant and heat

stabilizer for plastic

Zhejiang

Chloroparaffin-70 Polychlorinated

Paraffin

- flame retardant for

plastic, paint & adhesive

Shanghai, Shangdong,

Shenyang

Tetrabromophthalic

Anhydride

Phthalate flame retardant for plastic Zhejiang

Dibromocresyl Glycidyl

Ether

Polybromo Phenol flame retardant for plastic Jiangsu

Table 2. Output of manufactured persistent organic chemicals in China

References for Tables 1 & 2:Wang, L. S., Hua Gong Chan Pin Zong Ji, Shanghai Science & Technology Publisher, China, 1997Yu, Z. M., ZhongGuo Hua Gong Shang Pin Da Quan (Dian Wei Hei), ZhongGuo Wu Zi Chu Ban She, Beijing, China, 1993Yu, Z. M. ZhongGuo Hua Gong Shang Pin Da Quan (Dian Wei Hei), ZhongGuo Wu Zi Chu Ban She, Beijing, China, 1991Wu, W. Z., Schramn, K. W., Henkelmann, B., Yediler, A., & Kettrup, A., PCDD/Fs, PCBs, HCHs, and HCB in sediments and soil of Ya-er lake in China: Results on residual levels and correlation to the organic carbon and the particle size , Chemosphere, Vol. 34, No. 1, pp. 191-202, 1997Jiang, K. Li, L. J., Chen, Y. D., & Jin, J., Determination of PCDD/Fs and Dioxin-like PCBs in Chinese commercial PCBs and emissions from a testing PCB incineration, Chemosphere, Vol. 34, No. 5 - 7, pp. 941-950, 1997

Product Chemical 1992 (tonnes) 1993 (tonnes)Dibutyl Phthalate 73,989 85,151Dioctyl Phthalate 153,171 139,162Dimethoxyethyl Phthalate 49 42

Plasticizer Butyl Benzyl Phthalate 313 467Disodecyl Phthalate 1,770 220Mixed Phthalate 228 211Dicotyl-p-Phthalate 12,269 6,505Chlorinated Paraffin 43,787 40,189

Stabilizer for Plastic andRubber

Dibasic Lead Phthalate &Organometallic Stabilizer

4,595 4,635

Table 3. Import & export of persistent organic chemicals in Hong Kong

References:1) Hong Kong Trade Statistics - Import,1993 -1996, Census and Statistics Department, Hong Kong2) Hong Kong Trade Statistics - Exports and Re-exports, 1993 -1996, Census and Statistics Department, Hong Kong

Import StatisticsCommodities Unit 1993 1994 1995 1996

Aromatic Cyclic Alcohols and their Halogenated, Sulphonated, Nitrated or Nitrosated Derivatives kg 1,062,493 1,343,189 1,533,794 1,562,531Halogenated, Sulphonated, Nitrated and Nitrosated Derivatives of Phenols or Phenol-Alcohol kg 758,776 950,525 1,003,327 591,640Phthalic Anhydride kg 2,353,072 5,524,191 15,168,230 81,414Dioctyl-o-Phthalates kg 61,357,396 90,387,720 80,122,197 688,107Dimethyl-t-Phthalates kg NA 16,000 483,000 NAInsecticides kg 15,248,510 16,049,884 16,556,661 12,544,204Compound Plasticizers for Rubber or Plastics HK$ 209,127 351,368 668,319 652,260Liquid Dielectic Transformer No. 47 510 499 10209

Export StatisticsCommodities Unit 1993 1994 1995 1996

Insecticides kg NA 4,082,026 NA 3,934,040Compound Plasticizers for Rubber or Plastics HK$ 40,278 NA 79,961 52,995

Table 4. The order of high priority environmental pollutants of China

Group NameAcute ToxicityLD50 (mg/kg)

Chronic ToxicityTCLO (mg/kg)

Aquatic-lifeToxicity (mg/L)

Dichloromethane 2136 / /Trichloromethane 908 20.1 /Tetrachloromethane 2800 43 (human) /

1. Halogenated 1,2-Dichloroethane 678 1338 / Methane / 1,1,1-Trichloroethane 5100 43 / Ethane 1,1,2-Trichloroethane 582 532 /

1,1,2,2-Tetrachloroethane 30 / /Trichloroethylene 3670 594 /Tetrachloroethane 3005 2100 /Tribromomethane 1147 1100 /

2. Benzene p-Xylene 3810 150 10-100Chlorobenzene 2910 750 1-100

3. Chlorinated o-Dichlorobenzene 670 / / Benzene p-Dichlorobenzene 500 / /

Hexachlorobenzene 10000 / /4. Polychinated Biphenyls

PCBs 2000 0.067 / day /

Table 4. (cont.)




Phenol 317 300 /m-Cresol 242 143 /

5. Phenol 2,4-Dichlorophenol 580 / /2,4,6-Trichlorophenol 820 / /Pentachlorophenol 27 50 1p-Nitrophenol 250 10 /p-Nitro-toluene 1960 / /

6.Nitrobenzen 2,4-Dinitro-toluene 268 / /Trinitro-toluene 795 / /p-Nitrochlorobenzene 420 / /2,4-Dinitro-1-chlorobenzene 1070 / /Aniline 250 150 /Dinitroaniline 418 1.1 /

7. Aniline p-Nitroaniline 750 / /2,6-Dilchloro-1-nitroaniline 1500 (oral-mice) / /

Table 4. (cont.)




Naphthalene 1250 (oral-mice) / 1-10Fluoranthene 2000 / /

8. Polyaromatic Benzo[b]fluoranthene / / / Hydrocarbon Benzo[k]fluoranthene / / /

Benzo[a]pyrene 50 0.455 /Indeno[1,2,3-c,d]pyrene / / /Benzo[g,h,i]perylene / / /Dimethyl-phthalate 6800 1125 /

9. Phthalate Di-n-butyl-phthalate 8000 140 /Dioctyl-phthalate 6513 5000 /Hexachloro-cyclohexane 88 / /DDT 113 6 <1DDV 25 15 /

10. Pesticides Dimethoate 140 / /Parathion 6 / /Parathion-methyl 9 / /Nithofen 740 37.5 /Trichorfon 150 2.2 /

11.Acrylonitrile Acrylonitrile 78 37.9 /

Reference:National Environmental Protection Agency, Database: Environmental Protection. Hebei Publisher, 1990

The use of persistent organics in China and Hong Kong

Conclusion

1) Many manufactured persistent organic chemicals (eg. phthalate, halowax, polybromophenol, etc.) are actively used in heat stabilizer, plasticizer and flame retardant.

2) More than 200,000 tonnes and 40,000 tonnes of phthalate and halowax are produced every year.

3) China produces about 5000 tonnes of Pentachlorophenol (PCP) annually (Wu et al., 1997).

4) Environmental concerns on liquid dielectric transform are growing owing to the existence of PCBs and PCB substitutes.

5) Input of persistent organic chemicals to HK is much more than output.

3. Case Study – PCBs, PCDDs & PCDFs in China

- Industrial production started from 1965 and ceased at 1974

- 10,000 tonnes produced during that periods- Two different types of Chinese commercial PCBs –

PCB3 and PCB5, which are similar to Aroclor 1242 and 1254 respectively

- Pentachlorobiphenyl is still applied as one of the additives in the manufacture of paint today.

- Starting from 1985, more than 2000 transforms have been demolished.

• Scientific Studies

• Yang Y. H., Sheng G. Y., Fu J. M. & Min Y. S. Organochlorinated compounds in waters of the Pearl River Delta region. Environmental Monitoring and Assessment, 44, 567 – 575, 1997

Ranged from 0.80 to 9.23 g/LSewage water > river water

• Chu S. G., Xu X. B., Fang Y. P., The distribution and environmental behaviour of PCBs in classic polluted sites, Acta Scientia Circumstantiae, 15, 1, 1995

Bio-magnification in reference contaminated area[PCBs] in water < sediment < fish

Bio-accumulation in fish[PCBs] in muscle < bile < gallbladder < liver

• Chu S. G., Xi Z. Q., Xu X. B, Polychlorinated Biphenyl (PCB) Congeners in Mussel and other Mollusc from Da Chen Island, East China Sea, Bull. Environ. Contam. Toxicol., 55, 682 – 688, 1995

Bio-concentration ranged from 1.40 to 9.34 g/kg[PCBs] correlated with distance of sampling sites from the estuary

of the river.

• Chu S., Xi Z., Xu X. Zhang Y., Xu Y, Induction of Micronuclei in peripheral erythrocytes of Misgurnus anguillicaudatus by polychlorinated biphenyls. Bull. Environ. Contam. Toxicol., 57, 179 -182, 1996

Water polluted by PCBs have a possible mutagenicity of aquatic organisms

Increase on the incidence of micronuclei with the increase of [PCB3] and time exposureSuitability of assessing peripheral blood of fish for the induction of

micronuclei as a short term test for monitoring environmental genotoxicants

Xi Z. Q., Chu S. G., Xu X. B., Zhang Y. Y. Xu. Y., Fang Y.P., Li W., Effects of PCBs on the Electrolyte Balance in Blood of Crucian Carp, Research Centre for Eco-Environmental Sciences, Academia Sinica, Beijing, China, (in process)

Effect on dielectric concentration balance in the plasma of carp[Na+] [K+]

No observable change in [Ca2+] & [Mg2+]

Zheng M. H., Bao Z. C., Wang K. O., Xu X. B., Levels of PCDDs and PCDFs in the Bleached Pulp from Chinese Pulp and Paper Industry, Bull. Environ. Contam. Toxicol., 59, 90 – 93, 1997

PCDDs in pulp ranged from 140.0 to 390.5 pg/g dry pulpPCDFs in pulp ranged from 7.3 to 80.4 pg/g dry pulp

• Zheng M. H., Bao Z. C., Wang K. O., Xu X. B., Polychlorinated Dibenzo – p Dioxins and Dibenzofurans in lake Sediments from Chinese Schistosomiasis Area, Bull. Environ. Contam. Toxicol., 59, 653 – 656, 1997

Total PCDDs & PCDFs were 15760 ng/g and 2260 ng/g in Na-PCP respectivelyLevels of PCDDs & PCDFs in lake sediments ranged from 51 to 220 ng/g and 0.3 to 15 ng/g respectively

Table 5. Benzo(a)pyrene concentration in China soil and atmosphere from industrial and non-industrial area

4. Case study - PAHs in China

Soil g/g Atmosphere g/100m3

Wheat, corn field RiceSamplinglocation n mean n mean n mean

Deposition(100t/km2/month)

Industrialarea

17 229.4 133.0 23 179.785.5 20 8.76 4.81 164.0 62.4

Non-industrial

area

16 0.8 0.7 18 3.6 2.9 21 0.5 0.04 27.0 11.9

Table 6. PAH concentrations at different diameter of suspended particulate in air

Reference:Liu, S. J. and Wu, Y. Carcinogenic polycyclic aromatic hydrocarbon in environment. Environment Protection in China. 1995.

Particlediameter

Pyrene Chrysene Benz(a)anthracene

m Industrialarea

Residentialarea

Ruralarea

Industrialarea

Residentialarea

Ruralarea

Industrialarea

Residentialarea

Ruralarea

>7.0 3.68 0.57 0.18 3.25 0.58 0.10 2.49 0.49 0.097.0-3.3 1.67 0.28 0.10 3.38 0.42 0.25 1.57 0.34 0.383.3-2.0 2.53 0.51 0.12 2.73 1.29 0.14 1.63 0.29 0.362.0-1.1 1.79 0.75 0.22 2.82 0.72 0.38 3.46 0.61 0.951.1 5.22 7.94 0.48 7.17 4.51 0.82 9.75 1.22 3.50Total 14.89 10.05 1.10 19.35 7.52 1.69 18.90 2.95 5.28

Particlediameter

Perylene Benzo(a)pyrene

m Industrial area

Residential area

Ruralarea

Industrial area

Residential area

Ruralarea

>7.0 14.26 4.86 0.94 2.04 0.92 0.467.0-3.3 20.57 1.08 2.33 2.24 0.75 0.703.3-2.0 6.21 1.16 1.20 1.49 0.77 0.552.0-1.1 31.90 3.30 2.28 3.39 0.80 0.641.1 41.73 33.09 5.96 6.75 3.08 3.06Total 114.67 43.49 12.71 15.91 6.32 5.41

Case Study - PAHs in China

Conclusion

The background values of benzo(a)pyrene ranged from 1.5-28 g/kg in soil.

Benzo(a)pyrene levels in soils collected from cultivated field in industrial area were 179-223 g/kg.

More than 6 times higher than those in non-industrial area.

Elevated benzo(a)pyrene levels in air of industrial area due to combustion process.

Particle size affects the absorption of PAH to suspended particles in the atmosphere.

94% PAH was associated with the particles smaller than 2.9 m.

PAH containing particles could settle down in lung via respiration

Pose a potential health problem to human beings.

Sediment Water Breast milk Biota Soil Fly ash Food

PC

B (

ppb)

1x10-8

1x10-4

1

1x104

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

China Taiwan Hong Kong

5. Total PCBs, PCDDs, PCDFs and PAHs in abiotic and biotic samples from China, Taiwan and Hong Kong

Figure 1a. Mean concentration (ppb) of total PCBs in differentmonitoring samples from China, Taiwan and Hong Kong.


1x104

1

1x10-4

1x10-8 N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

PC

DD

(pp

b)


Figure 1b. Mean concentration (ppb) of total PCDDs in differentmonitoring samples from China, Taiwan and Hong Kong.


PCD

F (p

pb)

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

1x10-8

1x10-4

1

1x104


Figure 1c. Mean concentration (ppb) of total PCDFs in differentmonitoring samples from China, Taiwan and Hong Kong.


PAH

(pp

b)

1x10-8

1x10-4

1

1x104

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A


Figure 1d. Mean concentration (ppb) of total PAHs in differentmonitoring samples from China, Taiwan and Hong Kong.

Total PCBs, PCDDs, PCDFs and PAHs in abiotic and biotic samples from China, Taiwan and Hong Kong

Conclusion

Distribution patterns of PCBs in sediments showed smaller spatial variations.

In HK and Taiwan, total PCBs retained more in sediments than that in China.

Only a few monitoring surveys are available on the PCDD, PCDF, and PAH contamination in air, water, sediments of China.

Spatial distribution of such contamination is unclear.

Multi-compartment monitoring is essential to elucidate the behavior and fate of persistent organic chemicals and to assess the current status of contamination.

Table 7. Concentrationsa of total PCBs and total PAHs in sediments from Victoria Harbour (Connell et al., 1998).

6. Case Study - Study of PCBs and PAHs in Hong Kong

tance Units Harbour station Typhoon sheltersVS1 VS2 VS3 VS4 VS5 VS6 VS8 VS9 VS10 VS14 VS12 to VS14 &

VS16 to VS20Period

l PCBs g kg-1

(dw)10 16 6.8 14 5.6 11 4.3 3.2 27 38-81 1992b

l PCBs g kg-1

(ww)NA 25.5

(23.7)10.2(6.8)

NA 9.5(8.3)

16.7(13.9)

NA 9.0(4.9)

14.5(13.7)

ND-169 1995-1996c

l PAHs mg Kg-1

(dw)5.6 12.7 12.6 14.0 9.6 3.1 3.9 1.20 68 454 ND-139 1992b

l PAHs g Kg -1

(ww)NA 191

(104)125

(126)NA 78

(51)336167)

NA 139(92)

135(88)

1159(811)

ND-824 1995-1996c

ND = not detected; NA = not available; ww = wet weight; dw = dry weight.a Means with standard deviations in parenthese where available.b Hong et al., 1995.c EPD, 1995 - 1996.

Reference:Connell, D. W., Wu, R. S. S., Richardson, B. J., Leung, K., Lam, P. S. K., and Connell, P. A. Occurrence of persistent organic contaminants and related substances in Hong Kong marine areas: an Overview. Marine Pollution Bulletin 36:376-384, 1998

Table 8. Concentrationsa of total PCBs in sediments collected in Hong Kong marine areas (Water Control Zones) during 1995-1996b (Connell et al., 1998)

Stations Average (SD)ZoneS1 S2 S3 S4 S5 S6 S7

Deep Bay 10.0(7.0) 8.75(3.5) 6.75(2.3) 15.5(16.6) NA NA NA 10.25(3.7)Eastern Buffer 6.25(2.5) 5.25(0.5) 33.0(27.4)c 7.25(2.6) NA NA NA 12.9(13.3)

Junk Bay NA 9.0(2.7) NA NA NA NA NA 9.0(2.7)Mirs Bayb 6.75(3.5) 6.5(3.0) 7.75(3.2) 5.0(0) 5.0(0) 9.75(9.5) 6.25(2.5) 6.7(1.5)

North Western NA 6.7(2.0) 7.0(2.8) 7.25(3.8) 14.7(11.8)c 9.75(4.2) NA 9.1(3.4)Port Shelter 12.6(11.5)c 6.75(3.5)c 5.75(2.25) 11.75(12.2) 5.3(0.5) 5.75(1.5) 5.0(1.6) 7.5(3.2)

Southern 5.25(0.5) 5.0(0) 5.5(1.0) 8.3(5.7) 8.25(3.9) 5.0(0) 16.0(1.6)c 7.6(3.9)Tolo Harbour NA 7.0(2.6) 7.7(7.2) 5.0(0) 10.0(9.2) NA 15.25(16.6)c 8.99(3.9)

Western 10.5(4.5) 7.75(5.5) NA NA NA NA NA 9.1(1.9)

NA = not available.a g kg-1 wet weight with standard deviations in parentheses.b EPD, 1995-1996.c Typhoon shelters and sheltered anchorages.d Mirs Bay Stations continued: S8 5.3(0.5); S9 6.6 (2.8); s10 5.0 (0); S11 7.6 (4.6); S12 6.3 (2.3); S13 4.6 (0.5); S14 6.6 (2.0); S15 8.5 (7.0); S16 6.0 (1.7); S17 9.0 (6.9).

Table 9. Concentrationsa of total PAHs in sediments collected in Hong Kong marine areas (Water Control Zones) during 1995-1996b (Connell et al., 1998)

StationsZoneS1 S2 S3 S4 S5 S6 S7

Average (SD)

Humanpopulationc

(x 105)Deep Bay 231(213.7) 64(29.1) 51(15.3) 47(13.1) NA NA NA 98.8(88.9) 3.68

Eastern Buffer 42(5.2) 40(1.4) 230(158.3)d 60(13.2) NA NA NA 93.6(92.5) 2.32Junk Bay 45(9.9) NA NA NA NA NA NA 45.5(9.9) 0.82Mirs Bayb 41(1.5) 41(3.6) 40(1.4) 40(1.2) 40(1.2) 44(3.2) 40(1.4) 40.4(1.5) 0.23

North Western NA 62(19.7) 44(4.9) 49(9.9) 125(51.9)d 61(28.1) NA 68.6(32.6) 3.86Port Shelter 120(117.7)d 42(2.0)d 43(5.3) 48(11.3) 40(1.15) 43(6.9) 51(11.8) 55.7(28.8) 0.48

Southern 43(5.4) 49(8.5) 170(174.4) 104(53.6) 60(5.7) 41(2.8) 156(44.8)d 89.5(55.0) 2.62Tolo Harbour NA 40(2.1) 40(2.1) 39(2.6) 41(2.6) NA 50(13.9)d 42.41(4.4) 7.10

Western 60(13.5) NA NA NA NA NA NA 58.1(3.4) 3.95

NA = not available.a g kg-1 wet weight with standard deviations in parentheses.b EPD, 1995-1996.c Typhoon shelters and sheltered anchorages.d Mirs Bay Stations continued: S8 5.3(0.5); S9 6.6 (2.8); S10 5.0 (0); S11 7.6 (4.6); S12 6.3 (2.3); S13 4.6 (0.5); S14 6.6 (2.0); S15 8.5 (7.0); S16 6.0 (1.7); S17 9.0 (6.9).

Case Study - PCBs and PAHs in HK

Conclusion

Total PCBs and PAH in sediments have been monitored at 13 stations in Victoria Harbour.

PCBs and PAHs in marine sediments at 66 stations in 10 water quality zones in Hong Kong were collated and analysed between 1987 and 1996.

Contamination by the PCBs was lower than world wide standards (up to 25.5 g/kg wet weight).

Substantial petroleum contamination in Victoria Harbour sediments (up to 116 g/kg wet weight)

Total PCBs and PAHs were widely distributed in Hong Kong sediments (background concentrations of 5 to 9.8 g kg-1 and 40 to 60 g kg-1 wet weight respectively).

Substantial contamination was found in typhoon shelters (total PCBs up to 169 g kg-1 wet weight; total PAHs, up to 1159 g kg-1 wet weight).

Much of the PCBs and PAHs due to industrial discharges and stormwater run-off (trace concentration originating from road ways, motor vehicle discharges, disposal of electrical equipment and other items).

Sewage would also be expected to contain trace concentrations.

PAHs are probably of combustion origin and the levels in the various water quality zones show an approximate relationship with the size of the human population in the catchment.

7. Polycyclic aromatic hydrocarbons in water and sediment of South China River

Study sites:

Pearl River, Deep Bay, Shenzhen River, Reservoir (Control site), Hong Kong Rivers

Samples:

River water and sediments at 16 locations in Pearl River Delta.

Analysis:

16 PAHs were investigated.

Figure 2. Map of South China showing the sampling locations of sediment and water.

Figure 3a. Mean concentrations of total PAHs in sediment of South China rivers.

Pearl River

Deep Bay

Shenzhen River

Control

Hong Kong Rivers

Sites

a b c d e f g h i j k l m n o p

(g/

Kg

dry

wt)

0

500

1000

1500

2000

2500

Pearl River

Deep Bay

Shenzhen River

Control

Hong Kong Rivers

Figure 3b. Mean concentrations of total PAHs in surface water of South China rivers

Sites

a b c d e f g h i j k l m n o p

(g/

L)

0

1

2

3

4

5

6

Table 10. Present results compared with Sediment Quality Criteria for organic micro-pollutants (expressed in µg/kg)

Present study Hong Kong and China guidelines European guidelines

CompoundPearlRiver

ShenzhenRiver

HongKong

HK(Target A)

HK(Trigger B)

HK(Action C)

China DutchIntervention value

UK targetvalue

Fluoranthene <10-280 <10-140 <10-459 1200 5250 7000 ND ND NDBenzo(b)fluoranthene

<10-188 <10-52 <10-167 550 2250 3000 ND ND ND

Benzo(k)fluoranthene

<10-134 <10-33 <10-80 550 2250 3000 ND ND ND

Benzo(a)pyrene <10-547 <10-35 <10-136 200 2250 3000 ND ND NDBenzo(ghi)perlene

<10-148 <10-27 <10-120 200 2250 3000 ND ND ND

Indeno (123-cd)pyrene

<10-36 <10-35 <10-40 200 2250 3000 ND ND ND

Total PAH(Sum 10)

455.25-1199.3

185.51-674.25

142.27-1384.2

ND ND ND ND 40000 1000

Target A – indicate the desired quality for fairly clean sediment; they slightly exceed but are close to the background levels. Trigger B – indicate that moderate pollution occurs. The target values proposed equate to about 50% of the trigger levels. Action C – indicate heavily polluted sites (Lau Wong, 1991). Intervention Values are now available to identify “serious contamination” of soils, sludges and groundwaters and to indicate

when remediation is necessary. “Target Values” are specified to indicate desirable uncontaminated chemical contents of both soils and water.

References:Contaminated Spoil Management Study. (1991). Final Report, Vol. 1. Mott MacDonald Hong Kong Ltd., Agreement CE 30/90. Environmental Protection Department, Hong Kong Government.Cairney, T. (1996). Contaminated Land Problems and Solutions.

Table 11. Present results compared with Water Quality Criteria for organic micro-pollutants (expressed in µg/l)

Present study China guidelines European guidelines

Compound Pearl RiverShenzhen

River Hong Kong ChinaUK

target valueDutch

Intervention valueNaphthalene <0.1-1.4 <0.1-1.2 <0.1-0.5 ND 0.1 70Anthracene <0.1-0.1 <0.1-0.2 <0.1-0.2 ND 0.02 5Phenanthrene <0.1-1.8 <0.1-3.0 <0.1-4.3 ND 0.02 5Fluoranthene <0.1-0.2 <0.1-0.3 <0.1-0.2 ND 0.005 1Benz(a)anthracene <0.1-0.1 <0.1 <0.1 ND 0.002 0.5Chrysen <0.1-0.2 <0.1-0.2 <0.1-0.3 ND 0.002 0.05Benzo(b)fluoranthene <0.1 <0.1 <0.1 ND ND NDBenzo(k)fluoranthene <0.1 <0.1 <0.1 ND 0.001 0.05Benzo(a)pyrene <0.1 <0.1 <0.1 0.002 0.001 0.05Benzo(ghi)perlene <0.1 <0.1 <0.1 ND 0.002 0.05Indeno (123-cd)pyrene <0.1 <0.1 <0.1 ND 0.0004 0.05Total PAH (Sum 10) <0.1-2.934 0.1-2.942 <0.1-3.433 ND ND ND

- Target A – indicate the desired quality for fairly clean sediment; they slightly exceed but are close to the background levels.- Trigger B – indicate that moderate pollution occurs. The target values proposed equate to about 50% of the trigger levels.- Action C – indicate heavily polluted sites.- Intervention Values are now available to identify “serious contamination” of soils, sludges and groundwaters and to indicate

when remediation is necessary. - Target Values are specified to indicate desirable uncontaminated chemical contents of both soils and water.

Reference Lu, R. (1995). Standards for domestic drinking water. Handbook of Regulations on Environmental Protection in China.

Polycyclic aromatic hydrocarbonsin water and sediment of South China river

Conclusion

Total PAHs in the different locations show wide variations.

Elevated levels of total PAHs in sediments (up to 2200 g/kg dry wt.) and water (up to 5 g/L) were detected in some locations.

Elevated concentrations of PAHs are observed in location adjacent to industrial area.

Significant PAH contamination was found to be due to Benzo(a)pyrene and chrysene in sediment and water, respectively (slightly exceed the recommended guidelines).

8. PCBs in freshwater fish and sediments collected from the Pearl River Delta and Hong Kong.

Study sites:Pearl River Delta:

fish ponds: Dongguan, Shunde, Nanhai, Zhongshan and Shenzhen

Hong Kong: Fish ponds: Au Tau, Mai Po and San Tin Rivers: Shing Mun River, Lam Tsuen River and Tai Po River

Samples: sediments and freshwater fish

Freshwater fish species: black bass, tilapia, common carp, big head, silver carp and grass carp.

Table 12a. Concentrations of PCBs in sediments collected from the Pearl River Delta and Hong Kong.

PCBs(ng/g dry wt) References

Sediment pond sediment, Pearl River Delta < 1 present studypond sediment, Hong Kong < 1 ibidriver sediment, Hong Kong 43-461 ibid

river sediment, Hong Kong 12.7-46.0 Chui et al. 1990Victoria Harbor 3.2-81 Hong et al. 1995Tolo Harbor 5.0-15.3 Connell et al.

1998

Table 12b. Concentrations of PCBs in fish flesh collected from the Pearl River Delta and Hong Kong.

PCBs(g/g wet wt) References

Fish flesh pond fish, Pearl River Delta 0.0009-0.023 present study

pond fish, Hong Kong 0.0003-0.0075

ibid

Tilapia in river, Hong Kong 0.066-0.078 ibid

Tilapia and Mullet in Mai PoMarshes

0.0025-0.017 Liang et al. 1998

Public health guidelines for fishery products: NEPA, China 0.2 US Food and Drugs Administration 2 US EPA 0.01

If an adult weighing 70 kg consumed 6.5 g of fish every day with PCBs concentration greater than 0.01 g/g wet wt, for 70 years, the risk would correspond to one cancer death per 100,000 person.

Note: Data in the present study printed in bold-face exceeded the US EPD recommended guideline.

Figure 4. Bioaccumulation of PCBs in different fishes

0

1

2

3

4

5

blackbass

tilapia big head silvercarp

grasscarp

PCBsa

cb

b

aµ

g/g

lipi

d

PCBs in freshwater fish and sediments collected from the Pearl River Delta and Hong Kong.

Conclusion

1. PCBs levels in pond sediments were less than 1 ng/g (dry wt).

2. PCBs concentrations in river sediments ranged from 43-461 ng/g (dry wt), which were higher than the previous studies in relation to Shing Mun River (12.7-46.0 ng/g dry wt, Chui et al. 1991), Tolo Harbour (5.0-15.3 ng/g wet wt, Connell et al. 1998) and Victoria Harbour (3.2-81 ng/g dry wt, Hong et al. 1995).

3. Although PCBs concentrations in fish flesh collected from fish ponds in the Pearl River Delta and Hong Kong did not exceed the NEPA maximum permissible limits (0.2 g/g wet wt), 16% of fish collected from the Pearl River Delta and 100% of fish collected from the rivers in Hong Kong exceeded the more stringent guidelines of US EPA (0.01 g/g wet wt).

4. Factors affecting bio-accumulation of PCBs in fish.

Ecological niches: feeding habits affects PCBs accumulation in freshwater fish cultured in wastewater system at Au Tau.

Possible uptake pathways for sediment-sorbed PCBs accumulated in tilapia: ingestion sediment and/or contact with contaminated particles contributed to the major uptake route rather than water.

9. Induction of Cytochrome P4501A1 Gene Expression in Tilapia Exposed to Coastal Sediment

The Outline Method of Reverse-Transcriptase-Polymerase-Chain-Reaction (RT-PCR)

Liver tissues Total RNA

PCR products

Agarose gel electrophoresis

Specific primersfor CYP1A1

RT-PCR

•The present method is very sensitive in detecting CYP1A1 gene expression, which is specific to organic contaminants.

•The method is simple and rapid.

Marker

Control

PCB/3h

PCB/6h

PCB/12h

Sedimentexposure

Induction of CYP1A1 gene expression in fish liver tissues using RT-PCR..

~270 bp

Induction of Cytochrome P4501A1 gene expression in Tilapia exposed to coastal sediment

Conclusion

Exposure of tilapia to the sediments of PCBs (i.p. injection)

induced CYP1A1 levels in the liver tissues.

The biomarker is highly sensitive to the organic pollutant.

This enables us to monitor trace organic contamination in local waters.

General Conclusion Only a few monitoring surveys are available on the flame

retardant, PCB substitute and phthalates contamination in air, water, and sediment of China, although they are manufactured and used.

The order of highly concern on persistent organic chemicals is PCBs > PAH > phthalate > pesticides.

The data indicates that the sediments of China are contaminated with a relatively high concentration of total PAHs, as well as lower concentrations of total PCBs, PCDDs and PCDFs.

Benzo(a)pyrene is mostly concerned PAH component in China.

In Hong Kong the most concern persistent organic chemicals are PCBs, PAH and pesticides.

Background concentrations of 5 to 9.8 g kg-1wet weight of total PCBs and 40 to 60 g kg-1 wet weight of total PAHs in Hong Kong marine sediment.

Elevated concentrations of PCBs and PAHs were found in Victoria Harbour sediment in the range 9.56 to25.5 g kg-1 and 66 to 116 g kg-1, respectively.

Substantial contamination was found in typhoon shelters (total PCBs, up to 169 g kg-1 wet weight; total PAHs, up to 115 g kg-1 wet weight).

Sediments in Hong Kong rivers contained PAH and PCB concentrations of 194 to 2199 g kg-1 dry wt and 12.7 to 461 g kg-1 dry wt, respectively.

More monitoring work should be done to get a clear geographical distribution of persistent organic chemicals in our region.

Multi-compartment monitoring and bioaccumulation assessment is essential to elucidate the behavior and fate of persistent organics, also to assess the current status of contamination.

persistent manufactured chemicals for non-pesticide applications and persistent by-products of...

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