环境化学课程报告

1. Report for Environmental Chemistry 环境化学课程报告 --Introduction of PAHs and Dioxins 制作：王昊、王沛 Designed by Hao Wang & Pei Wang

2. Glimpse of the two chemicals • PAHs, abbreviation of “Polycyclic aromatic hydrocarbons”, are potent atmospheric pollutants that consist of fused aromatic rings and do not contain heteroatoms or carry substituents.[1] • Dioxins refer to polychlorinated dibenzo-p-dioxin(PCDDs) and polychlorinated dibenzofuran (PCDFs). [1] http://en.wikipedia.org/wiki/Polycyclic_aromatic_hydrocarbon

3. On PAHs--Source Volcanic activity Natural source Natural fire Biosynthesis Source: Main source Fossil fuels’ burning Anthropogenic source Incense Incomplete combustion of other substances containing hydrocarbons Tobacco Fired food

4. On PAHs 16 US EPA priority PAHs naphthalene acenaphthylene acenaphthene fluorene phenanthrene anthracene fluoranthene pyrene probable human carcinogens benzo[k]fluoranthene benzo[b]fluoranthene benzo[a]anthracene chrysene benzo[a]pyrene indeno[1,2,3-cd]pyrene benzo[g,h,i]perylene dibenzo[a,h]anthrancene

5. On PAHs--Environmental level 16 US EPA priority PAHs were present in majority water samples. The concentrations of ∑ PAHs in water ranged from 144.3 to 2360 ng·L-1 with the mean value of 662ng·L-1. 26 sample sites along Yellow River The concentrations of ∑ PAHs in SPMs ranged from 506.6 to 10,510 ng·g-1dry weight with the mean value of 4100ng·g-1 . The concentrations of ∑ PAHs in sediments ranged from 16.4 to 1358 ng· g-1 dry weight with the mean value of 182.0ng·g-1. [2] Jian-Hui Sun et al. Distribution of polycyclic aromatic hydrocarbons (PAHs) in Henan Reach of the Yellow River, Middle China [J] Ecotoxicology and Environmental Safety 72 (2009) 1614– 1624

6. On PAHs--Environmental level Concentrations of different rings PAHs in different sample sites’ water were quite different. Concentration of 2-, 3-, 4-, 5-, 6-ring and total PAHs in water in Henan Reach of the Yellow River

7. On PAHs--Environmental level PAS-GP-II passive sampler Glass bucket Dustfall samples were collected from March, 2005 to January, 2006 at 4 sampling sites in the southeastern suburb of Beijing. Concentrations of ∑16PAHs ranged from 0.72 to 40.45 µg g−1. 2–3 ring PAH compounds were the dominant ones in dustfall samples. [3]Shucai Zhang et al. Dry deposition of atmospheric polycyclic aromatic hydrocarbons(PAHs) in the southeast suburb of Beijing, China[J] Atmospheric Research 89 (2008) 138–148

8. On PAHs--Environmental level High molecular weight compounds tended to stay in TSP, while more low and medium molecular weight ones could be found in gas phase and dustfall. Relative percentage of 16 PAH compounds in 3 media

9. On PAHs--Toxicity 1 Teratogenic, carcinogenic and mutagenic properties. 2 Inhibit microbial growth 3 Photo-induced toxicity

10. On PAHs--Toxicity PAHs had long been thought to be direct carcinogens, however, as research on them deepens, people have realized that PAHs themselves do not have a directly negative effect on our health, but the substances generated through metabolismworks. Bay region Discussion of the Mechanism L region K region

11. On PAHs--Control measure Physical methods 1 Microwave Technology Coagulation& sedimentation … … Chemical method 2 Photocatalytic oxidation Supercritical water oxidation … … 3 Biological methods … … Biodegradation by Microbes Phytoremediation

12. The Stockholm Convention polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) belongs to the initial 12 POPs of the convention. Annex A (Elimination) Annex B (Restriction) Annex C (Unintentional production) Parties must take measures to reduce the unintentional releases of chemicals listed under Annex C with the goal of continuing minimization and, where feasible, ultimate elimination. [4]http://chm.pops.int/default.aspx

13. On PCDD/Fs--Source Industrial-Chemical Processes Natural Sources Thermal Processes Secondary Sources [5]Heidelore Fiedler, Dioxins and Furans (PCDD/PCDF The Handbook of Environmental Chemistry Vol. 3 Part O ,Persistent Organic Pollutants Chapter6

14. On PCDD/Fs--Environmental level The most toxic organic compound ever found The presence of dioxins and dioxin-like PCBs is expressed as toxic equivalents (TEQ) after multiplication of congener-specific concentration levels with toxicity equivalency factors (TEF) developed based on their relative toxicity compared to 2,3,7,8-TCDD.

15. On PCDD/Fs--Environmental Levels Summary of PCDD/PCDF concentrations in soil from EU Member States. Concentrations in ng TEQ/kg d·m.

16. On PCDD/Fs--Environmental Levels Summary of air concentrations from EU Member States. Concentrations of ambient air samples in fg TEQ/m3 and deposition in pg TEQ/m2·d

17. On PCDD/Fs--Environmental level The mean level of PCDD/Fs in the free range egg samples was 5.7(1.79/0.314) times higher than those in the caged egg samples. Geographical locations of the areas where egg sampleswere collected in Taiwan. 17 PCDD/Fs were determined using HRGC-HRMS( high resolution gas chromatography-high resolution mass spectrometry) [6] Jing-Fang Hsu et al. Elevated PCDD/F Levels and Distinctive PCDD/F CongenerProfiles in Free Range Eggs[J], Agriculture and food chemistry, 2010, 58, 7708–7714

18. On PCDD/Fs--Toxicity The changes in Yushchenko's face were due to chloracne, which results from dioxin poisoning , and dioxin levels found in Yushchenko's blood was 6,000 times above normal! The former president of Ukraine Victor Yushchenko In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphenyls (PCBs) and 1 g of dioxins were distributed to animal farms in Belgium.

19. On PCDD/Fs--Toxicity Reproductive toxicity Neurotoxicity Immunotoxicity Carcinogenic toxicity Endocrine disruptors … …

20. On PCDD/Fs--Toxicity Chinese dietary intake of dioxins is 72.48pg per person per day,equals1.21pg/kg BW per person per day and 36.24pg/kg BW per person per month. equal Dioxin level caused by waste incineration in some advanced countries [7] Tao Liao et al. Pollution and analysis of Dioxin-li ke compounds in food [J] Food and Machinery, 2008 24(4) 153-165

21. On PCDD/Fs--Control measure For Treatment Plant: Dioxins begin to decompose at about 500 ° C, and can be completely decomposed in 2s at 800 ° C. . New technology to improve the combustion temperature For regulators: Higher standards on atmospheric environmental quality and dioxin tolerable daily intake(TDI) Database on Dioxin-like compounds in different food and environmental mediums of China Promote Refuse Sorting For us:

22. On PCDD/Fs--Control measure Reduce pollution Electricity A waste incineration plant in Osaka, Japan

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