Contamination Characteristic And Source Of Polybrominated Diphenyl Ethers In Environmantal And Demic Media Of Shanghai

Located in the estuary of Yangtze River, Shanghai is the center for industrial and economic development in China. In recent years, with the intensifying of urbanization and industrialization, the manufacture and usage of fire retardants in Shanghai increase day by day. Now many papers manifest that fire retardants are widespread in all kinds of environmental media. As one of fire retardants, PBDEs are used widely, degrade difficultly and can migrate long-distance in the environment. Besides, they have biological toxicity effects, which are included: interference of immune toxicity nervous system toxicity, reproduction and developmental toxicity and hepatotoxicity. This study set the sediment in Shanghai as the target object and conducted a systematic and indepth research about the pollution level, composition patterns and possible sources of 13 PBDEs in the target medium. This paper also make a potential ecological risk assessment to judge the influence between PBDEs and bentonic organisms. In the next step, human serum samples from Jiading District, Shanghai, were collected to detect and analyze the pollution level and content of each homolog. By comparison of PBDEs’ concentrations, the relationship of PBDEs’ pollution levels in the environmental medium and human body was reflected. The major findings and conclusions are as follows:①This study unveiled that PBDEs were widespread in the sediment of Shanghai. The concentrations of PBDEs in the southeast was highest(1008.5~13087.1 pg g-1 dw, average, 3502.59 pg g-1 dw) and then in the middle(876.0~8697.8 pg g-1 dw,average, 3113.23 pg g-1 dw). The pollution states were relatively low in both west(124.0~4203.3 pg g-1 dw, average, 2567.36 pg g-1 dw) and north areas(933.9~2184.1 pg g-1 dw, average, 1543.96 pg g-1 dw). By comparison of correlational researches from domestic and abroad, it is clear that the concentration of BDE-209 in Shanghai was in the intermediate level which was lower than in surrounding cities but higher than in Taiwan and Hainan. BDE-209 was the main congener which accounted for more than 72% of the total. PCA was applied in the analysis of the sources of PBDEs congeners and the research reveals that flame retardant products used in business were the main source of PBDEs in sediments in rivers. Meanwhile, the relatively high factor loadings of low brominated PBDEs congeners indicated high brominated PBDEs could transform low brominated PBDEs in different pathways of degradation. Besides, it turned out from the ecological risk assessment that bentonic organisms have few ecological risk made by PBDEs in the sediments. However, there are potential possibilities to improve the ecological risk when high concentration of De BDEs transform into highly toxic Pe BDEs. Thus, further researches should be conducted to investigate the risk from PBDEs to aquatic ecosystem.②This study explored the analysis methods and instrument conditions about PBDEs in human serum. The RSD of appearance time of standard PBDEs was between 0.01% and 0.07% which was relatively stable. Nevertheless, the RSD of peak areas was between 15% and 22% which had high deviation, but still was within a reasonable range. This paper introduced two methods of analysis about PBDEs in serum. Method one: liquid-liquid extraction was used to extract lipid, GPC was used to remove the lipid and PBDEs was extracted by organic solvent. Method one was somewhat complicated and its recovery is not stabilization. Method two: Solid phase extraction was used to extract PBDEs and it was convenient as separation, extract and purification were mixed into one step. The recovery range of PBDEs congeners was 49.2%~144.7% and two internal standards’ recoveries were 111.6% and 132.4% in method one. While in method two it was 81.1%~117.2%,105.8% and 114.6%. By this token, method two was proper to detect PBDEs in human serum. In our study, the mean concentration of PBDEs in human serum was 6.677 ng/g, and the range was 0.545~26.743 ng/g, which meant that the substance was widespread in serum. In total PBDEs congeners, the proportion of Hexa-BDEs was generally high and Penta-BDEs and Hepta-BDEs were in the less place. Compared with domestic and abroad, the concentrations of PBDEs in serum in Jiading, Shanghai was in the intermediate level which was similar in Menorca, Spanish, Indiana and Australia, far below in Dalian, China.③This paper discussed about the contamination characteristic and source of brominated flame retardants in environmental and demic media of Shanghai. The concentrations of PBDEs in sediment was 0.124~13.09 ng/g and BDE-209 account for more than 72% of total PBDEs congeners. However, the values of PBDEs in serum was 0.545~26.743 ng/g and BDE-153, BDE-154 occupied the highest proportion. Thus we can know that concentrations of PBDEs in sediment and serum were in the same order of magnitudes but the main congeners were different. According to the study in our research team, the values of other environmental media in Shanghai exceed in sediment but the main congener was the same BDE-209, which meant that they all came from the contamination of industrial application of PBDEs and migrated and transformed in the environmental media. When the high brominated PBDEs enter human body, they may transform low brominated PBDEs in metabolic process and gather in the serum. Therefore, we detected high value of Hexa BDE in the serum samples.