Assessment of the known and the unknown: Brominated flame retardants

Polybrominated diphenyl ethers (PBDEs) are widely used as a class of brominated flame-retardants. As a congener of PBDEs, 2,2′,4,4′-tetrabromodiphenylether (BDE 47) is the most toxic congener to animals. In this study, we applied metabolomics to characterize the gender-specific metabolic responses in mussel Mytilus galloprovincialis exposed to BDE 47 for 30 days. Results indicated the apparent gender-specific responses in M. galloprovincialis with BDE 47 exposures (1 and 10 μg/L) at metabolite level. Basically, BDE 47 induced disruption in osmotic regulation and altered energy metabolism in mussels, via differential metabolic pathways. In addition, the hormesis phenomenon was observed in both male and female mussel samples exposed the two concentrations of BDE 47, indicated by the contrarily altered metabolites from two BDE 47 treatments (1 and 10 μg/L), respectively. Overall, this study confirmed the gender-specific responses to BDE 47 exposures in mussels and suggested the gender differences should be considered in marine ecotoxicology.