Halogenated flame retardants (HFRs) in surface sediment from the Pearl River Delta region and Mirs Bay, South China

A total of 43 surface sediment collected from rivers and the estuaries in the Pearl River Delta (PRD) region and Mirs Bay from the South China were analyzed for twelve halogenated flame retardants (HFRs) including polybrominated diphenyl ethers (PBDEs) using liquid chromatography-tandem mass spectrometer system. Their levels, spacial distribution, congener profiles and possible sources were investigated. Decabromodiphenyl ethane (DBDPE) was the predominant contaminant (1.520-1714 ng/g dw) in the study area exceeding those of PBDEs (8.090-595.8 ng/g dw), implying that DBDPE has been the predominant HFR products in this region in recent years in addition to PBDEs. Whereas the ratio of [DBDPE/BDE 209] varied among samples, this is indicative of different usage patterns of HFRs between PRD region and Mirs Bay. The PBDEs congener was dominated by BDE 209, with the average value accounting for 86.8% of the total PBDE in the sediment samples.