Polybrominated diphenyl ethers (PBDEs) in the riverine and marine sediments of the Laizhou Bay area, North China†
Abstract
62 riverine and marine sediments were collected from the Laizhou Bay area, where the largest manufacturing base of brominated flame retardants (BFRs) in Asia is located. Eight polybrominated diphenyl ethers (PBDEs) were analyzed to investigate the impact of rapidly-developed bromine industries on the regional aquatic system. PBDE concentrations varied largely in riverine sediments. Σ7PBDEs (including BDE 28, 47, 99, 100, 153, 154 and 183) and BDE 209 ranged from 0.01 to 53 ng g−1 dw and from 0.74 to 285 ng g−1 dw with a mean value of 4.5 ng g−1 dw and 54 ng g−1 dw, respectively, indicating a strong influence of direct pollution discharges from local factories. In marine sediments, Σ7PBDEs and BDE 209 ranged from not detected (nd) to 0.66 ng g−1 dw and from 0.66 to 12 ng g−1 dw with a mean value of 0.32 ng g−1 dw and 5.1 ng g−1 dw, respectively. PBDE concentrations were mostly <10 ng g−1 dw for Σ7PBDEs and <50 ng g−1 dw for BDE 209, which are at a relatively low level for monitored riverine and coastal sediments around the world. Even at the most contaminated sites in Laizhou Bay area, PBDE concentrations were not among the highest concentrations reported in the literature. Congener compositions were dominated by BDE 209 (57.2–99.9% of the sum of BDE congeners), with minor contributions from penta- and octa-BDE products. Tri- to octa-BDE congeners were well correlated among each other (r > 0.75) and thus sources from similar