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Persistent manufactured chemicals for non-pesticide applications and persistent by-products of industrial and combustion process in China and Hong Kong Ming H. Wong Hong Kong Baptist University GEF PDF-B Workshop, Jan 1999. Table of contents.

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  1. Persistent manufactured chemicals for non-pesticide applications and persistent by-products of industrial and combustion process in China and Hong KongMing H. WongHong Kong Baptist UniversityGEF PDF-B Workshop, Jan 1999

  2. 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.

  3. 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.

  4. 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.

  5. 2. The use of persistent organics in China and Hong Kong Table 1a. Manufactured persistent organic chemicals in China: Heat Stabilizer

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

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

  8. 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, 1997 Yu, Z. M., ZhongGuo Hua Gong Shang Pin Da Quan (Dian Wei Hei), ZhongGuo Wu Zi Chu Ban She, Beijing, China, 1993 Yu, Z. M. ZhongGuo Hua Gong Shang Pin Da Quan (Dian Wei Hei), ZhongGuo Wu Zi Chu Ban She, Beijing, China, 1991 Wu, 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, 1997 Jiang, 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

  9. 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 Kong 2) Hong Kong Trade Statistics - Exports and Re-exports, 1993 -1996, Census and Statistics Department, Hong Kong

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

  11. Table 4. (cont.)

  12. Table 4. (cont.) Reference: National Environmental Protection Agency, Database: Environmental Protection. Hebei Publisher, 1990

  13. 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.

  14. 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.

  15. • 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/L • Sewage 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

  16. • 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, 1995Bio-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 exposure Suitability of assessing peripheral blood of fish for the induction of micronuclei as a short term test for monitoring environmental genotoxicants

  17.  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 pulp PCDFs in pulp ranged from 7.3 to 80.4 pg/g dry pulp

  18. • 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 respectively Levels of PCDDs & PCDFs in lake sediments ranged from 51 to 220 ng/g and 0.3 to 15 ng/g respectively

  19. 4. Case study - PAHs in China Table 5. Benzo(a)pyrene concentration in China soil and atmosphere from industrial and non-industrial area

  20. 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.

  21. 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.

  22. 5. Total PCBs, PCDDs, PCDFs and PAHs in abiotic and biotic samples from China, Taiwan and Hong Kong China Taiwan Hong Kong Figure 1a. Mean concentration (ppb) of total PCBs in different monitoring samples from China, Taiwan and Hong Kong.

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

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

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

  26. 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.

  27. 6. Case Study - Study of PCBs and PAHs in Hong Kong Table 7. Concentrationsa of total PCBs and total PAHs in sediments from Victoria Harbour (Connell et al., 1998). 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

  28. Table 8. Concentrationsa of total PCBs in sediments collected in Hong Kong marine areas (Water Control Zones) during 1995-1996b (Connell et al., 1998) NA = not available.amg 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).

  29. Table 9. Concentrationsa of total PAHs in sediments collected in Hong Kong marine areas (Water Control Zones) during 1995-1996b (Connell et al., 1998) NA = not available.amg 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).

  30. 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 mg kg-1 and 40 to 60 mg kg-1 wet weight respectively).

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

  32. 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.

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

  34. Pearl River Deep Bay Shenzhen River Control Hong Kong Rivers Figure 3a. Mean concentrations of total PAHs in sediment of South China rivers.

  35. Pearl River Deep Bay Shenzhen River Control Hong Kong Rivers Figure 3b. Mean concentrations of total PAHs in surface water of South China rivers

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

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

  38. 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).

  39. 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.

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

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

  42. Figure 4. Bioaccumulation of PCBs in different fishes µg/g lipid

  43. 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).

  44. 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.

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

  46. The Outline Method of Reverse-Transcriptase- Polymerase-Chain-Reaction (RT-PCR) Liver tissues Total RNA Specific primers for CYP1A1 RT-PCR PCR products • The present method is very sensitive • in detecting CYP1A1 gene expression, • which is specific to organic contaminants. • The method is simple and rapid. Agarose gel electrophoresis

  47. Marker Control PCB/3h PCB/6h PCB/12h Sediment exposure ~270 bp Induction of CYP1A1 gene expression in fish liver tissues using RT-PCR..

  48. 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.

  49. 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.

  50.  In Hong Kong the most concern persistent organic chemicals are PCBs, PAH and pesticides.  Background concentrations of 5 to 9.8 mg kg-1wet weight of total PCBs and 40 to 60 mg 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 to 25.5 mg kg-1 and 66 to 116 mg kg-1, respectively.  Substantial contamination was found in typhoon shelters (total PCBs, up to 169 mg kg-1 wet weight; total PAHs, up to 115 mg kg-1 wet weight).

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