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

Abstract

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 571.4 pg g À1 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.

A Review of Hydroxylated and Methoxylated Brominated Diphenyl Ethers in Marine Environments

“…In China, OH/MeO-PBDEs were found to be much higher in marine sediments from the East China Sea (11.4−129.1 pg/g dw for ΣOH-PBDEs and nd-838.1 pg/g dw for ΣMeO-PBDEs) and southern Yellow Sea (58.9-402. To explore the source of OH/MeO-PBDEs in marine sediments, investigated the correlations between OH-and MeO-PBDEs and phytoplankton biomarker (brassicasterol, dinosterol and alkenones) concentrations collected from the East China Sea and the southern Yellow Sea, and found significant positive correlations between the concentrations of most compounds [11,25], suggesting that phytoplankton may be the potential producers of OH-and MeO-PBDEs in the marine environment. Although interconversion of 6-MeO-BDE 47 and 6-OH-BDE 47 was investigated in sediment, the much lower conversion ratio from 6-MeO-BDE 47 to 6-OH-BDE 47 (0.010 ± 0.002) [26] and comparable levels of the two compounds in most surface sediments from the East China Sea suggest that a large proportion of 6-OH-BDE 47 may be from the natural production by marine organisms rather than from the conversion from 6-MeO-BDE 47 [25].…”

“…OH/MeO-PBDEs have been detected in various marine organisms, including biota at a low trophic level (algae, sponges, invertebrates) [2][3][4][5] to those at a high trophic level (seals, whales, polar bears) [6][7][8][9] from all over the world. In addition, OH/MeO-PBDEs have been detected in marine abiotic environmental matrices, such as sea water and sediment [3,[10][11][12]. It is noteworthy that OH/MeO-PBDEs were also detected in humans [13][14][15][16][17].…”

Emerging environmental pollutants hydroxylated polybrominated diphenyl ethers: From analytical methods to toxicology research

“…∑OH‐PBDEs in bivalves are usually much higher than those in fishes (De la Torre et al, 2013; Liu et al, 2014; Kim et al, 2015; Liu et al, 2018). The high concentration of OH‐PBDEs in bivalves may come from algae and phytoplankton they feed on, which are the sources of the naturally occurring OH‐PBDEs (Fan et al, 2014a,b, 2015). In contrast to bivalves, marine animals in higher trophic levels, such as dolphins, sharks, and whales, do not accumulate high levels of OH‐PBDEs (Montie et al, 2009; Nomiyama et al, 2011; 2011; DaZhang et al, 2012; Dahlberg et al, 2016).…”

“…The hydroxyl group is prone to locate at the ortho ‐positions to the biphenyl bond in the OH‐PBDEs detected in soil, and the microbial biomass may contribute to the transformation from PBDEs to OH‐PBDEs (Huang et al, 2010; Wang et al, 2014). OH‐PBDEs discovered in marine sediments help illustrate that except for transforming from PBDEs that are produced by industrial manufacture, some OH‐PBDEs (e.g., 6‐OH‐BDE‐47, 2′‐OH‐BDE‐68) also have natural origination in oceans (Wan et al, 2009; Haraguchi et al, 2010; Fan et al, 2014a,b, 2015). Multiple genera of algae, such as Coccolithophorids, Caulerpa taxifolia, Padina minor, and Gracilaria edulis, can produce OH‐PBDEs (Haraguchi et al, 2010; Fan et al, 2014a,b).…”