Halogenated phenolic contaminants in the blood of marine mammals from Japanese coastal waters

- Specific differences in the accumulation profiles of OH-PCBs were found in marine mammals.
- 6OH-BDE47 was dominant isomer in all marine mammals.
- 6OH-BDE47, 6MeO-BDE47 and 2,4,6-BPh showed significant positive correlations.
- Lower concentrations of brominated compounds were found in pinnipeds.
- Pinnipeds might have a capability to degrade organobromine compound.

Information on accumulation of halogenated phenolic contaminants in the blood of marine mammal is limited. The present study, we determined the residue levels and patterns of chlorinated and brominated phenolic contaminants (OH-PCBs, OH-PBDEs and bromophenols) in the blood collected from pinnipeds (northern fur seal, spotted seal, Steller sea lion and ribbon seal) and small cetaceans (harbor porpoise and Dall's porpoise) from Japanese coastal waters. Concentrations of PCBs and OH-PCBs found in pinnipeds were the same as in small cetaceans living in the same coastal area. However, significantly lower concentrations of brominated compounds (PBDEs, MeO-PBDEs, OH-PBDEs) were found in the blood of pinnipeds than the levels found in cetacean species which live same area (p < 0.05). This difference of accumulation pattern suggested pinnipeds have an enhanced capability to degrade organobromine compounds relative to cetaceans.