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Concentrations of 16 polybrominated diphenyl ether (PBDE) congeners were measured in river sediments, paddy soils and three species of paddy-field organisms (crab, loach and carp) collected from the Liaohe River Basin, northeastern China. The total contents of PBDEs (∑ 16 PBDEs) in sediments and paddy soils were in the ranges of 273.4–3246.3 pg/g dry weight (dw), and 192.1–1783.8 pg/g dw, respectively. BDE 209 was the dominant congener both in sediments and paddy soils. The concentrations of ∑ 16 PBDEs in sediments were significantly higher than those in the adjacent paddy soils, indicating a potential transport of PBDEs from river to paddy ecosystems via river water irrigation. The biota–soil accumulation factor (BSAF) was calculated as the ratio between the lipid-normalized concentration in paddy-field organisms and the total organic carbon-normalized concentration in paddy soil. The average BSAF values of ∑ 15 PBDEs followed the sequence of crab (3.6) > loach (3.3) > carp (2.1). BDE 154 had the highest BSAF value, and a parabolic trend between BSAF values of individual PBDE congeners and their log K OW values was observed. In view of the fact that crab had the larger BSAF value and higher lipid content, the ecological risk and health risk for crab cultivation in paddy fields should be of particular concern. [ABSTRACT FROM AUTHOR]

Congener specific distributions of polybrominated diphenyl ethers (PBDEs) were investigated in sediment and mussel (Mytilus edulis) collected from the coast of Bo Sea, China. The median values of BDE-209 and ΣPBDEs (including BDE-17, -28, -47, -66, -71, -85, -99, -100, -138, -153, -154, -183 and -190) were 2.29 and 0.16ngg−1 dry weight in sediment, and 2.43 and 0.68ngg−1 dry weight in mussel, respectively. BDE-209 was the predominant congener (61–99% in mussel and 75–99% in sediment except for one sample with 17%). Different congener patterns (excluding BDE-209) were observed between sediment and mussel, which were attributed to individual congener’s bioaccumulation potential and/or the ability to metabolize. The four most abundant congeners were BDE-47 (40.3%), -99 (22.5%), -71 (8.9%) and -28 (5.8%) in sediment, and -47 (36.4%), -28 (14.5%), -154 (8.6%) and -71 (8.6%) in mussel, respectively. The ratios of BDE-47/BDE-99 and BDE-100/BDE-99 in sediment were lower than those in mussel, indicating higher transformation and uptake rate of BDE-99 in mussel. The biota-sediment accumulation factor (BSAF) of individual PBDE congeners declined with the increase of their logarithm of octanol–water partition coefficients (log K OW) except for BDE-154, indicating congeners with higher log K OW were more likely to retain in sediment. These can be explained with a high affinity of these compounds for carbonaceous geosorbents, and molecular steric hindrance that limits large, very hydrophobic organic compounds from penetrating the cellular membranes. [Copyright &y& Elsevier]