Bioaccumulation of novel brominated flame retardants in a marine food web: A comprehensive analysis of occurrence, trophic transfer, and interfering factors.

Abstract

Although the concept of bioaccumulation for novel brominated flame retardants (NBFRs) is clear, the process and interfering factors of bioaccumulation are still not fully understood. The present study comprehensively evaluated the occurrence, transfer and interfering factors of NBFRs in a marine food web to provide new thought and perspective for the bioaccumulation of these compounds. The occurrence of 17 NBFRs were determined from 8 water, 8 sediment and 303 organism samples collected from Dalian Bay, China. The trophic magnification factor (TMF), the bioaccumulation factor (BAF) and the biota sediment accumulation factor (BSAF) were calculated in a plankton-mollusk-crustacean-fish based food webs. Results showed that among the 17 target NBFRs, 11 compounds appeared the significant trophic magnification and 2 compounds of decabromodiphenylethane (DBDPE) and octabromotrimethylphenylindane (OBIND) presented the significant trophic dilution. The significant positive correlation was found between the value of BAFs and the trophic level for 15 NBFRs (except DBDPE and OBIND), indicating that the species with high BAFs values were all at high trophic levels. The stable and rapid metabolic rates of DBDPE and OBIND constitute the main reason why they hardly accumulate in high trophic level organisms. The BSAFs of NBFRs in swimming organisms were much higher than that in mollusks and crustaceans, indicating that a large part of NBFRs accumulated from food webs. The significant positive correlation between TMF and BAF was observed in high trophic level organisms, which demonstrates the important role of high trophic level organisms in evaluating the bioaccumulation effect of NBFRs.