Ecotoxicological risk assessment of polybrominated diphenyl ethers in sediment on benthic organisms at some areas of the Northern Vietnam

Abstract

In this study, the authors determined levels and patterns of Polybrominated diphenyl ethers (PBDEs) in surface sediment samples collected from some areas in the Northern Vietnam. Concentration of PBDEs in all samples ranged from 1.31 to 1715 ng/g dry weight with mean value as 324 ng/g. Concentrations (mean and range) of total 8 most popular PBDEs congeners in sediment from Trieu Khuc village, Hanoi; Bui Dau village, Hung Yen province and some craft villages in Bac Ninh province were 537 (363- 864); 432 (1.31-1715) and 2.89 (1.77-3.87) ng/g, respectively. The most predominant congeners in sediment were BDE-209 and BDE-99. The relatively high levels of PBDEs in sediment from informal e-waste recycling sites in Trieu Khuc and Bui Dau in comparison with those from non-recycling areas suggested that recycling activities were making potential sources of PBDEs emission. The ecotoxicological risks of sedimentary PBDEs on benthic organisms (Daphina magna) in studied areas were evaluated by the estimation of risk quotient for each congeners. Risk quotients of most samples were in range of 0 < RQs ≤ 100 (equals to no significant risk or potential for adverse effects); however, in rarely extraordinary sites such as Trieu Khuc and Bui Dau, high value of RQs for some congeners such as BDE-99, -100, -183 and -209 indicated that potential adverse effects should be expected.