Concentrations and bioavailability of polyhalogenated biphenyls in sediments from Yongding New River in Tianjin,China
天津永定新河沉积物中多卤联苯的污染水平和生物有效性

Concentrations of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) in sediments and simultaneously sampled daphnia from Yongding New River in Tianjin, China were determined to preliminarily assess their potential ecological risks. According to the results, 18 PCB congers and 14 PBB congeners could be detected in all sediment samples, and their total concentrations ranged from 492.4 to 3251.9 ng·g~(-1) and 429. 7 to 2950. 0 ng·g~(-1)( normalized to total organic carbon) , respectively. Their concentrations in daphnia samples were from 301. 8 to 1765. 4 ng·g~(-1) and 309.7 to 1987. 8 ng·g~(-1)( normalized to lipids) , respectively. The calculated in-situ bio-sediment accumulation factors (BSAFs) of PCBs and PBBs ranged from 0. 1 to 1. 3 and 0. 1 to 3. 0, respectively. Most BSAFs were much lower than those predicted by equilibrium partitioning theory, and no significant relationship between BSAF and logA_(ow)(p >0. 08) was found. It can be concluded that concentrations of PCBs and PBBs in sediments from Yongding New River were higher than many reported from other areas, but the bioavailability for most of sediment-associated PCBs and PBBs was low and varied greatly among different sampling sites (coefficients of variation: 20% ～90% ).