Preliminary Studies On Polybrominated Diphenyl Ethers And Decabromodiphenyl Ethane In Various Typical Environmental Matrices Of Shanghai

With the continuous development of social economics and further growing regionalurbanization and industrialization, numerous categories of flame retardants, includingpolybrominated diphenyl ethers (PBDEs) and polybromodiphyl ethane (DBDPE), continuouslyspread to the environment and cause increasingly serious pollution. As an international metropolis,industrial structure of Shanghai mainly consists of heavy industries, which makes the resourceconsumption and pollution discharge at a high level. What is more, with the increasing ofindustries of computer and automobile, the pollution of flame retardants in the environment havebeen aggravating. Meanwhile, with the rapid growing of population, the total amount of garbage,automobile exhaust and emission of other pollutants continuously increase, which makes Shanghaiface serious problems of environmental pollution.The research objects of the present study aimed to understanding the pollution levels, spatialdistribution, isomeric composition, possible sources and potential ecological risk of8PBDEs(including BDE-28,-47,-99,-100,-153,154,-183and-209) and DBDPE in variousenvironmental mediums of Shanghai, and supplying data of the pollution relations between thoseenvironmental mediums, and precondition for formulating strategies of regional or globalcontrolling as well. The major findings and conclusions are as follows:(1) This study unveiled the pollution levels, spatial and seasonal distributions and potentialpollution sources of PBDEs in the sediment from principal watersheds of Shanghai (includingHuangpu River, Suzhou Creek and Yunzao Creek) for the first time. Furthermore, the potentialecological risk caused by PBDEs was also studied in this study, which supplied importantscientific basis for controlling the discharge of PBDEs and protecting the local ecologicalenvironment.The results showed that PBDEs were detected in all the sediment samples, indicating thatthese contaminants were ubiquitous in riverine environment of Shanghai. Compared to otherglobal studies, it could be found that the levels of BDE-209in sediment were relativly high, whilethose of the total concentrations of the other PBDE congeners (except for BDE-209) wererelatively low. BDE-209accounted for more than97%of the total PBDEs in each of the sediment samples.Of the other individual PBDE congeners measured exclusion of BDE-209, BDE-47and BDE-99were the most abundant, followed by BDE-28. The results of Spearman correlation coefficient testshowed that BDE-209significantly correlated with total concentration of PBDEs in sediments,which indicated BDE-209mostly contributed to PBDE contaminants in sediments. PBDEs insediments of Shanghai mainly derived from the commercial flame retardants of PBDEs. Thehigher brominated PBDE homologues in sediment may transform into the lowers through differentpaths.With the hazard quotient approach, PBDEs were estimated to pose no hazard to benthicorganisms in riverine sediments in Shanghai at present. However, due to high concentration ofdeca-BDE and the high toxicity of penta-BDE, potential risk of PBDEs to organisms inecosystems of Shanghai watersheds may be still an issue of concern.(2) This study unveiled the pollution levles, distributions and potential sources of PBDEs inindoor dust and human hair samples from campus environment as well. The sources of PBDEs indust and hair samples were analyzed, and correlation analysis of PBDE homologues in both dustand hair samples were conducted.The results showed that PBDEs could be found in all the indoor dust and human hair samples,implying these pollutants had been widely spreaded in the non-occupational exposureenvironment. All the detection frequencies of PBDE congeners were found to be100%, whilemost PBDE congeners showed good detection frequencies (>50%) in hair samples except forBDE-100and BDE-154.BDE-209was the predominant congener among all the PBDEs in both dust and hair samples.BDE-47and BDE-99were the second dominant congeners in detected samples. Spearmancorrelation coefficient test and pricipal component analysis showed that PBDEs in dust and hairsamples mainly derived from the commercial PBDEs, especially commercial decabrominateddiphenyl ethers. Through the correlation coefficient test, significant positive correlations wereobserved between human hair and indoor dust for BDE-47(r=0.44, p=0.048) and BDE-99(r=0.68, p=0.025).(3) This study reported the contamination levels and distribution characteristics of DBDPEin non-biological samples (sediment) and biological samples (human hair) from Shanghai area for the first time.The results showed that DBDPE was detectable in all the sediment and hair samples, whichimplied this emerging brominated flame retardant had been widely distributed in differentenvironmental mediums in Shanghai. Significant correlations were found between DBDPE andPBDEs in sediment, however there was no correlation between the two substances in hair samples.Such phenomena demonstrated DBDPE and BDE-209in sediment shared common pollutionsources, and sources of the two substances might be more random. In addition, the correlationsbetween DBDPE and TOC in the summer sediment samples were better, but less in the wintersamples.Average concentrations of DBDPE detected in the sediments of different rivers were infollowing descending order: Suzhou Creek> Huangpu River> Yunzao Creek. The genderdifference of DBDPE concentrations in hair was similar to other pollutants, such as PBDEs, PCBs,OCPs and so on; pollutant concentrations in female hair samples are always higher than those inmales, namely. The average concentration of DBDPE in female hair was3.4times higher than thatin males in the present study.