A Big Picture View of Halogenated Chemical Exposures in China

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1 Green Science Policy Institute Symposium on Reducing Exposure to Toxic Chemicals in China August 22, 2009; Beijing, China A Big Picture View of Halogenated Chemical Exposures in China Eddy Y. Zeng State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences

2 Persistent Halogenated Compounds (PHCs) OCPs Organochlorine pesticides Likely derived from e- waste PBDEs PCBs PCDD/Fs PBBs TBBPA PBDD/Fs ClPAHs PAHs Polybrominated diphenly ethers Polychlorinated biphenyls Polychlorinated dibenzo-p-dioxins and dibenzofurans Polybrominated biphenyls Tetrabromobisphenol A Polybrominated dibenzo-p-dioxins and dibenzofurans Chlorinated polycyclic aromatic hydrocarbons Polycyclic aromatic hydrocarbons

3 Contents 1. E-waste in China 2. Estimated inventories of e-waste derived PHCs in the environment of China 3. Human exposure to PHCs in China 4. Recommendations to containing e-waste tsunami in China

4 Flow of Global E-Waste Approximately 70% of e-waste generated worldwide is processed in China every year From:

5 Localities of E-Waste Processing Sites Ni and Zeng, ES&T, 2009

6 Composition of E-Waste Generated in the U.S. China has been importing e-waste for over 10 years, receiving 50 80% of the U.S. obsolete computers (500 million computers became obsolete from 1997 to 2007). However, computers comprise only 4.4% of e-waste totals. The most recent data available were compiled in Percentage of total is labeled on the top of each bar. Ni and Zeng, ES&T, 2009

7 Emissions of PBDEs in China Chinese domestic production of BFRs in 2006 was ~80,000 metric tons (Development Trends of Fire Retardants in China, 2008) The amount of PBDEs imported to China in the form of e-waste was estimated at 35,000 metric tons/year (Guan et al., 2007) The amount of PBDEs accumulated from all BFRcontaining commercial products in China may reach 200,000 metric tons/year (Ni and Zeng, unpublished)

8 The State of E-Waste in China Quantity increases rapidly Out of control? Duel sources Accelerating domestic demand for electronic appliances and devices Tremendous amounts of e-waste have been illegally imported to China Flow into rural areas A large number of small-scale e-waste processing sites are expected to be in operation in China

9 The State of E-Waste in China Improper and crude recycling techniques Toner sweeping, open burning of plastics or plasticscontaining parts, cathode-ray tube cracking and dumping, circuit board recycling, acid stripping of chips, plastic chipping and melting and direct dumping of waste residues

10 Movement and Impact of E-Waste in China Importation Domestic generation E-Waste in China Unsound recycling treatment Persistent halogenated compounds from e-waste emitted into ambient environment Impact on local environment Migration Impact on remote area Ni and Zeng, unpublished

11 Contents 1. E-waste in China 2. Estimated inventories of e-waste derived PHCs in the environment of China 3. Human exposure to PHCs in China 4. Recommendations to containing e-waste tsunami in China

12 E-Waste Sites under Investigation Ni and Zeng, unpublished

13 Data Analysis The amount of e-waste derived individual PHCs accumulated in the environment of China (I i, tons/yr) can be estimated with the following equation: I i = k V C i where k Conversion factor V Annual total amount (tons/yr) of e-waste generated in and imported to China C i Concentration (ng/g) of the ith compound in e-waste

14 Estimated annual accumulated inventories of polychlorinated dibenzop-dioxins and dibenzofurans (PCDD/Fs) in the environment of China Compounds Concentration (pg/g) a Inventory (g/year) PCDDs 2378-TCDD PeCDD HxCDD HxCDD HxCDD HpCDD OCDD Sum PCDFs 2378-TCDF PeCDF PeCDF HxCDF HxCDF HxCDF HxCDF HxCDF HxCDF OCDF Sum a Concentrations of PCDD/Fs in electronic shredder waste

15 Estimated annual accumulated inventories of chlorinated polycyclic aromatic hydrocarbons (ClPAHs) in the environment of China Compounds Concentration (ng/g) a Inventory (kg/year) ClPAHs 3,9-Cl2Phe ClFlu ClFlu ClPr ,9,10-Cl3Phe ClBaA ClBaP Sum a Concentrations of ClPAHs in electronic shredder waste. Individual congeners include 3,9- dichlorophenanthrene (3,9-Cl2Phe), 3-monochlorofluoranthene (3-ClFlu), 8- monochlorofluoranthene (8-ClFlu), 1-monochloropyrene (1-ClPyr), 3,9,10- trichlorophenanthrene(3,9,10-cl3phe), 7-monochlorobenz[a]anthracene (7-ClBaA), 6- monochlorobenzo[a]pyrene (6-ClBaP).

16 Estimated annual accumulated inventories of polybrominated diphenly ethers (PBDEs), tetrabromobisphenol A (TBBPA), polybrominated biphenyls (PBBs), polybrominated phenols (PBPs) in the environment of China. Compounds Concentration (ng/g) a Inventory (tons/year) PBDEs penta-bde hexa-bde hepta-bde octa-bde nona-bde deca-bde Sum TBBPA PBBs tetra-bb penta-bb hexa-bb Sum PBPs mono-bp di-bp tri-bp tetra-bp penta-bp Sum a Concentrations in plastics

17 A Couple of Observations PBDEs are the dominant components of PHCs in e-waste, followed by ClPAHs and PCDD/Fs PCDD/Fs and ClPAHs should not be neglected because they are mostly emitted from e-waste recycling processes

18 Contents 1. E-waste in China 2. Estimated inventories of e-waste derived PHCs in the environment of China 3. Human exposure to PHCs in China 4. Recommendations to containing e-waste tsunami in China

19 Internal Exposure No association between the duration of exposure to PBDEs and oxidative DNA damage However, extended exposure to PBDEs may have an effect on the levels of thyroid-stimulation hormone and genotoxic damage among the exposed population It is speculated that other e-waste derived PHC components in addition to PBDEs may also affect the balance of thyroid hormone homeostasis Yuan et al., ES&T, 2008

20 External Exposure Exposed Control Concentrations of PCDD/Fs (pg/g lipid) Taizhou placenta Taizhou human milk Taizhou hair Hangzhou placenta Hangzhou human milk Hangzhou hair Comparison of PCDD/F concentrations in people between exposed group (Taizhou) and control group (Hangzhou) Chan et al., ES&T, 2007

21 External Exposure Total Dietary Intake (ng/day) Exposed (Taizhou) Control (Yandang) 10 PBBs PBDEs PCBs Total dietary intakes of PBDEs, PCBs and PBBs by local residents of the exposed (Taizhou) and control groups (Yandang) Zhao et al., Sci. Total Environ., 2009

22 A Few Observations People residing near e-waste disposal areas are exposed to toxic substances via inhalation, in addition to dermal contact and consumption of local contaminated foods Food consumption is one of the most important routes for human exposure to PHCs of e-waste origin The magnitude of human exposure to these toxics in e-waste sites in China is at the high end of the global range

23 Outflows of PHCs from China via Fish Exportation A Other North America Couries the U.S South America Africa China Europe Other Asia Countries Oceania DDTs 50 HCHs 50 PCBs 50 PBDEs 50 DDTs 90 HCHs 90 PCBs 90 PBDEs 90 B Macao China Hong Kong Korea Japan Taiwan DDTs 50 HCHs 50 PCBs 50 PBDEs 50 DDTs 90 HCHs 90 PCBs 90 PBDEs 90 Outflows (grams) of DDTs, HCHs, PCBs, and PBDEs via fish exportation from China to (1) Europe, (2) North America except for the U.S., (3) the U.S., (4) Asia except for Korea, Japan, Taiwan, Hong Kong, and Macao, (5) South America, (6) Africa, (7) Oceania, (8) Korea, (9) Japan, (10) Taiwan, (11) Hong Kong, and (12) Macau. Japan, Korea and the U.S. are top three receptors of PHCs through fishery trade from China Meng et al., ES&T, 2007

24 Contents 1. E-waste in China 2. Estimated inventories of e-waste derived PHCs in the environment of China 3. Human exposure to PHCs in China 4. Recommendations to containing e-waste tsunami in China

25 1 June 2009 Issue

26 Recommendations to Containing E- Waste Tsunami in China Enhanced Law Enforcement The Chinese government must take steps to allocate sufficient resources to rigorously enforce existing environmental laws and regulations Minimization or Elimination of Manufacturing- Related Pollution Sources China should adopt more appropriate models to deal with the e-waste problem Increased International Collaboration One of the most effective ways to resolve the e-waste crisis

27 A Crazy Thought Why can t we adopt the same quota system as for CO 2 emissions to regulate e-waste? Based on the economic benefits from manufacturing electronic products containing fire retardants and other toxic ingredients Based on the per capita usage of electronic products (e.g., China ranks No. 62 and 106 in the per capita numbers of televisions and computers, respectively, while the U.S. ranks No. 3 and 4 in the same categories. From

28 Acknowledgements Personnel Hong Gang Ni (Shenzhen Graduate School of Peking University) Ying Guo (Guangzhou Institute of Geochemistry, CAS) Xiang-Zhou (Tongji University, Shanghai) Yu-Feng Guan (South China Normal University) Funding Sources National Natural Science Foundation of China Chinese Academy of Sciences

29 Thank you for your attention!