Methoxylated and hydroxylated polybrominated diphenyl ethers in surface sediments from the southern Yellow Sea: spatial distribution and potential producers

Environmental context Methoxylated and hydroxylated polybrominated diphenyl ethers are of increasing concern owing to their global distribution and potential ecological risks. We investigated the spatial distribution and sources of these brominated compounds in surface sediments from the southern Yellow Sea, China. The results suggest that marine phytoplankton may be the potential producers of these compounds, thereby providing new insights into their occurrence and provenance in marine environments. Abstract Methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have recently caused worldwide concern; however, there have been very limited studies on their presence in marine sediments. In the present study, MeO-PBDEs, OH-PBDEs and phytoplankton biomarkers were determined in surface sediments from the southern Yellow Sea. MeO-PBDEs and OH-PBDEs are ubiquitous in southern Yellow Sea sediments, with total contents ranging from 43.0 to 571.4pgg(-1) dry weight. High contents of these compounds mainly concentrated in the central southern Yellow Sea basin, and their spatial distributions generally presented a seaward-increasing trend. By comparing with total organic carbon and terrestrial organic matter contributions in sediments, these compounds were inferred to originate mainly from marine production rather than from terrigenous inputs. Statistical analysis shows that there are significant correlations between MeO-PBDEs, OH-PBDEs and phytoplankton biomarkers, indicating that MeO-PBDEs and OH-PBDEs are mainly natural compounds, and the phytoplankton are likely to be their potential producers in the southern Yellow Sea, especially for dinosterol.