Brominated flame retardants (BFRs) in marine food webs from Bohai Sea, China

In this study, brominated flame retardants (BFRs), including 13 polybrominated diphenyl ethers (PBDEs) and 17 novel brominated flame retardants (NBFRs) are determined in 18 species (including plankton, invertebrate, and fish) from Bohai Sea, China. Trophic transfer of these compounds is also assessed in the marine food web. Significant trophic magnification (p < 0.01) for 11 PBDE congeners (BDE-17, BDE-28, BDE-47, BDE-49, BDE-66, BDE-85, BDE-99, BDE-100, BDE-153, BDE-154 and BDE-183) is observed. No significant correlation is observed for BDE-138 (p = 0.06), and significant trophic dilution is observed for BDE-209 (p < 0.0001). In PBDEs, BDE66 has the highest TMF value of 3.9 (95% confidence interval (CI): 32-4.7), followed by BDE-47 (TMF: 3.8, 95% CI: 2.6-5.4) and BDE-28 (3.0, 22-4.1). For NBFRs, ATE. TBECH (indude alpha- and beta-isomer), PBBZ, TBCO ( indude alpha- and beta-isomer), PBT, DFFE, HBBZ, PBBA, BTBPE. PBEB and HCDBCO are observed significant trophic magnification (p < 0.01), significant trophic dilution is observed for BATE (p < 0.01), DBDPE (p < 0.001) and OBIND (p < 0.0001), no significant correlation is observed for p-TBX (p= 0.77). In NBIRs, PBT has the highest TMF value of 4.5 (95% CI: 3.1-6.3), followed by PBEB (TMF: 4.0, 95% CI: 2.1-7.6) and HCDBCO (3.9, 3.1-5.0). Regression analysis between K-OW and TMF values of BFRs suggest that TMF values have a trend of first rising and then falling against the values of log K-OW. Generally, chemicals with higher K-OW value have stronger trophic magnification capacity than those with lower ones, but due to the influence of bioavailability, the trophic magnification ability of the superhydrophobic compounds may be inhibited. To our best knowledge, this is the first report of trophic transfer of NBFRs in marine food web and trophic transfer of 9 NBFRs (alpha-TBECH, p-TBX, BATE. PBBZ, alpha-TBCO, alpha-TBCO, DFFE, OBIND, and HCDBCO) in aquatic food web. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, trophic transfer of PBDEs and NBFRs was investigated in marine food web in Bohai Sea, China. Significant trophic magnification was observed for certain PBDE congeners, while some NBFRs showed significant trophic dilution. Chemicals with higher K-OW values generally exhibited stronger trophic magnification capacity, but bioavailability could inhibit the trophic magnification ability of superhydrophobic compounds. This study is the first to report on the trophic transfer of NBFRs in marine food web and 9 NBFRs in aquatic food web.