Research On Bioconcentration And Biomagnification Of Polybrominated Diphenyl Ethers And Short-chain Chlorinated Paraffins In A Typical Northern Area Of China

Polybrominated diphenyl ethers (PBDEs) and short-chain chlorinated paraffins (SCCPs) are typical halogenated flame retardants. The research on their environmental occurrence and behavior has become an important issue. As one signatory country of "Stockholm Convention on Persistent Organic Pollutants (POPs)", it is essential to carry out the studies on residual levels, pollution characteristics and environmental behavior of PBDEs and SCCPs in typical environment matrixes, so as to provide theoretical basis and original data for ecological risk assessment of these chemicals.In this study, the occurrence and bioaccumulation of PBDEs and SCCPs was investigated in a typical northern area of China (including the Liaohe River Basin, the Liaodong Bay and coastal area around the Bohai Sea) by field sampling, samples pretreatment and gas chromatography-mass spectrometry analysis. The results are as follows:(1) The total PBDEs levels (ΣPBDEs) in the sediments, soils and organisms range from273.4to3246.3pg/g (dry weight, dw),192.1to1783.8pg/g (dw) and1.3to8.8ng/g (dw), respectively. Pearson correlation analysis and principal component analysis indicate that the PBDEs are mainly from the urban areas, the PBDE congener patterns in soils and sediments have no significant difference, and are irrespective of the traditional irrigation ways. Furthermore, the bio-sediment accumulation factors (BSAF) are>1, indicating the bioaccumulation of PBDEs.(2) The ΣPBDEs in different organisms ranged from0.14to11.7ng/g (dw), and BDE-47is a predominant congener. The trophic magnification factors (TMFs) of two kinds of food webs, Zooplankton-Invertebrates-Fish-Birds and Zooplankton-Invertebrates-Birds, are>1, indicating the apparent biomagnification of PBDEs and the influence of the food chain length. Furthermore, the four concentration ratios, BDE-99/100, BDE-99/47, BDE-153/154and BDE-183/154, decrease with the increase of the trophic level, suggesting their steady metabolism in the process of trophic transfer.(3) The ΣSCCPs in surface sediments and bivalves range from97.4to1756.7ng/g (dw) and476.4to3269.5ng/g (dw), respectively. The lowed carbon and chlorinated congener groups predominate in all the samples. The bio-sediment accumulation factors (BSAF) are>1, indicating the bioaccumulation of SCCPs in bivalves. Moreover, a significant linear relationship (r=0.37, p<0.01) between the BSAF of individual congeners and their logKOW values was observed.(4) The logarithm of bioaccumulation factors (BAF) for SCCPs range from4.5to5.6for all the organisms. The BSAFs of the major SCCPs range from0.1to7.3in eight benthic invertebrates. These values obviously vary with the aquatic species, implying that bioaccumulation of SCCPs is influenced by the local residual levels and the pollution profiles. The TMF ofCCPs was determined to be2.38in the Zooplankton-Shrimp-Fish food web, indicating the biomagnification potential of SCCPs in the marine ecosystem. Moreover, a significant linear relationship between the TMF values of individual congener groups of SCCPs and their logKow values was observed (r=0.66, p<0.01).