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Study on Contamination Levels of Dibenzo-p-dioxins and Dibenzofurans, Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers in Atmosphere of a Seaside City, P R China

Author: WangChunLei
Tutor: YangDaCheng；ZhangJianQing
School: Southwestern University
Course: Organic Chemistry
Keywords: Dioxins PCBs Polybrominated diphenyl ethers Atmosphere Exposure risk assessment
CLC: X51
Type: Master's thesis
Year: 2010
Downloads: 258
Quote: 1
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Abstract

The two ah British (of polychlorinated dibenzo-p-dioxins and dibenzofurans, the formation of PCDD / Fs), PCBs (poly-chlorinated biphenyls, PCBs) and polybrominated diphenyl ethers (polybrominated diphenyl ethers, PBDEs) and other persistent organic pollutants, the outstanding carcinogenic, mutagenic, teratogenic \The atmosphere in three persistent organic pollutants, can migrate through the atmosphere of this environmental media and enters the human body through the food chain or the respiratory tract, resulting in human exposure. This study reference the international authoritative standard method, using high resolution gas chromatography / high resolution double focusing magnetic mass spectrometer (HRGC / HRMS) trace organic pollutant analysis technology platform of wet and dry seasons the atmosphere of a city in China over 17 chlorinated - dibenzo - Bis (?) total of 44 English / furans, 18 PCBs and more than nine polybrominated diphenyl ether monomer pollution levels were analyzed further on the body of the three categories compounds the level of exposure to the risk assessment. The studies have shown that the atmosphere of the city, including wet and dry seasons, including two ah British concentration range of 103.32-11882.95fg / m ~ 3, the average 3426.84fg / m ~ 3, the median of value 2950.35fg / m - 3; toxicity equivalent concentration range of 11.45 to 370.12 fg I-TEQ / m to 3, an average of 157.49 fg I-TEQ / m ~ 3, the median value of 151.24 fg I-TEQ / m ~~ 3. polychlorinated biphenyls the total concentration range of 9.16 ~ 126.60 pg / m ~ 3, the average value of 52.72 pg / m ~ 3, the median value of 55.61 pg / the m ~~ 3. Which, the concentration of PCBs in six indicative range of 8.34 ~ 122.67 pg / m ~ 3, an average of 50.17 pg / m to 3 the median of value 52.81pg / m ~~; 12 second English-like PCBs concentration range referral 0.83 ~ 4.28 pg/m3, average 2.55 pg/m3, the median value of 2.69pg / m ~ 3. 12 class two (?) British polychlorinated biphenyls total TEQ (ΣTEQ-PCBs) range 1.81-19.55 fg WHO-TEQ / m3, the average of 10.94 fg WHO-TEQ / m ~ 3, the median value of 12.82 fg WHO-TEQ / m ~~ 3. Polybrominated diphenyl ethers concentration range of 9.21 ~ 168.86 pg / m ~ 3, the average concentration for 34.23 p / m 3, the median value of 19.30 pg / m ~ 3, wet period samples detected a monomer BDE-209, The concentration range of 13.05-172.51 pg / m ~ 3, an average of 49.67 pg / m ~ 3, the median value of 27.28 pg / m ~~ 3. Atmospheric samples (?) British in the average concentration of the dry season 3837.59fg/m3, the average concentration of the wet period 3016.10fg / m ~ 3 toxicity equivalent concentration were 135.41 fg I-TEQ / m ~ 3 and 179.57 fg I-TEQ / m ~ 3. PCBs in the dry season, the average concentration of 44.97 pg/m3, wet period the average concentration of 60.48 pg/m3; the TEQ were: 10.79fgWHO-TEQ / m 3 and 11.10 fg WHO-TEQ / m to 3. The dry season, the average concentration of polybrominated diphenyl ethers 14.81 pg / m ~ 3, the wet period's average concentration was 53.65 pg / m ~~. The comparative analysis of the two periods sample concentration found different pollutants have significant seasonal differences, namely the dry season (?) British concentration higher than the wet period, the concentration is higher than the dry season wet period of polychlorinated biphenyls and polybrominated diphenyl ethers . Studies have shown that the abundance there are large differences between the different monomers. In all the samples in the two periods, OCDD accounted II (?) Britain and the total concentration of the highest rate of monomer (> 20%), and 2,3,4,7,8-PeCDF contribution to the total TEQ The largest monomer. PCB-28 is indicative of PCBs in the highest concentration of monomer, PCB-118 is a class two (?) British PCBs highest concentration of monomer. With the results of other studies have shown that PCB-126, all samples the the total TEQ PCB compounds biggest contribution monomer, the contribution rate of 94%, followed by the monomer PCB-169. BDE-47 and BDE-99 (except BDE-209) is higher abundance configuration, but the decline in the dry season the proportion of the other monomer (such as BDE-28 in the two periods of monomers , BDE-153, BDE-183) content in the proportion of increase the monomer distribution tends to be averaged. The city atmosphere British TEQ levels similar to the average of Sao Paulo, Brazil, higher than Taiwan, Hong Kong and cities in Japan and Europe and the United States level than has been reported, but lower than South Korea's medium-sized cities and the Mainland, Beijing, Guangzhou and Shanghai average. The the PCBs the TEQ level with Yokohama, Manchester TEQ level close below Gyeonggi-do, South Korea, as well as the level of air pollution in Taizhou. The concentration levels of PBDEs in Chicago studied concentration level range, higher than the city level in Toronto, Canada, South Korea, Japan, Osaka and Kyoto, and Singapore, Guangzhou, Beijing, Taizhou City is lower than the domestic level through the respiratory tract Photo into the exposure risk assessment showed that PCDD / Fs day of the city's adult Inhalation exposure 0.0025-0.041 pg I-TEQ/kg/day: the child breathing intake of PCDD / Fs daily exposure to 0.0058 to 0.094 pg I-TEQ/kg/day. Polychlorinated biphenyls average adult respiratory intake for the 0.0018 pg WHO-TEQ/kg/day, the children average 0.0040 pg WHO-TEQ/kg/day. City residents daily intake of PCDD / Fs DL-PCBs total (including respiratory, dietary intake) for adults 1.39 pg WHO-TEQ/kg/day children the 5.52 pg WHO-TEQ/kg/day. Residents through the day Inhalation of PCDD / Fs amount of DL-PCBs proportion of the total intake for adults and children, respectively 2.09% and 1.21%, respectively. Daily inhalation exposure to polybrominated diphenyl ethers amount of 5.56 pg / kg / day. Children's Day respiratory exposure to 12.66 pg / kg / day.

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CLC: > Environmental science, safety science > Environmental pollution and its prevention > Atmospheric pollution and its control
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