Contamination Characteristic And Source Of Brominated Flame Retardants In Various Typical Environmental Matrices Of Shanghai

Shanghai is the center for industrial and economic development in China.Recently, all kinds of PBDEs-treated products are used frequently because of rapidincrease in population and industry. Available studies showed that PBDEs areubiquitous contaminant in different environment medium from Shanghai and theimpact of PBDEs on the environment and their potential risk for animal and humanhealth is a current concern for the scientific community for several years. However,little information is available on the emission sources, spatial distribution pattern andtemporal trend of PBDEs in megacity, especially for the novel brominated flameretardants. The research objects of the present study aimed to understanding thepollution levels, spatial distribution, composition patterns, possible sources, soilmass inventories and dust potential healthy risk of14PBDEs in different land useareas, and four novel brominated flame retardants in sediments from principalwatersheds of Shanghai were also studied. The major findings and conclusions are asfollows:①The optimal accelerate solvent extraction method was performed at100°Cwith DCM/HEX (3:1, V/V), and which for four novel brominated flame retardantswas performed at100°C with DCM/HEX (1:1, V/V). The cleanup procedure forsediment was performed by Florisil solid phase extraction cartridges with4mLhexane, and then eluted with4mL dichloromethane. The average recoveries of targetcompounds at two spiked levels (2,10μg L-1) were in the range of79.5%-119.7%,with relative standard deviations (RSDs) of2.6%-15.3%.②This study unveiled the pollution levels, spatial distributions and potentialpollution sources of PBDEs in soil and outdoor dust from different functional areasof Shanghai for the first time. BDE-209accounted for more than80%of the totalPBDEs in each of the soil samples. The mean concentrations of Σ14PBDEs in soilfrom different functional areas decreased in the following sequence: automobilemanufacture area＞commercial area＞residential area＞industrial area＞agricultural area＞parks. Σ14PBDEs statistic significant high was observed in automobilemanufacture area by anova analysis. The levels of BDE-209in soil were relativelyhigh, while those of the total concentrations of the other PBDE congeners (except forBDE-209) were relatively low in the world. BDE-209accounted for more than60%of the total PBDEs in each of the outdoor dust samples. Σ13PBDEs statisticsignificant high was observed in commercial area by anova analysis and Σ14PBDEsstatistic significant high was observed in commercial area except for parks by anovaanalysis. The levels of BDE-209in dust were relatively low, while those of the totalconcentrations of the other PBDE congeners (except for BDE-209) were moderate inPacific Asia area.③There was no significance among PBDEs between soil and outdoor dust bycanonical correlation analysis. The source apportionment of PBDEs in soil andoutdoor dust was carried out by correlation analysis and principal componentanalysis. The results indicated that these congeners have similar source and/orpathway in those environmental medium and degradation in the environment andatmospheric transport could also control the levels of contaminants in theenvironment. The relatively high factor loadings of low brominated PBDEscongeners indicated point source pollution and atmospheric precipitation was themajor contaminated pathway for soil and outdoor dust, respectively.④PBDEs soil mass inventories showed that residential area, agriculture areaand automobile manufacture area have most PBDEs soil mass inventories. Dustingestion was the major way leads to dust exposure, while dermal absorption was theminor way. The daily exposure dose of infants, toddlers and children was3-11foldshigher than adults. With the hazard quotient approach, four novel brominated flameretardants were estimated to pose no hazard to benthic organisms in riverinesediments in Shanghai at present.