Metabolism of PCBs by the Deepwater Sculpin ( Myoxocephalus thompsoni )

Great Lakes Institute for Environmental Research, University of Windsor, Windsor, Ontario, Canada
Environmental Science and Technology (Impact Factor: 5.33). 01/2002; 35(24):4747-52. DOI: 10.1021/es015571l
Source: PubMed


Methylsulfonyl-PCBs (MeSO2-PCBs) are hydrophobic organic contaminants that bioaccumulate in the environment similar to their parent molecules, PCBs. Previously, MeSO2-PCBs have primarily been identified in tissues of birds, humans, and other mammals. However, evidence now supports formation of these metabolites in deepwater sculpin, Myoxocephalus thompsoni, a benthic forage fish predominant in the Great Lakes. The ability of deepwater sculpin to form MeSO2-PCBs is unprecedented for a freshwater fish species and presents a novel biochemical pathway for organochlorine metabolism. Additionally, this appears to be a unique PCB metabolic pathway resulting in a reduction of as much as 10% in the sculpin PCB burden, which is further transformed into another class of organic contaminants in the Great Lakes ecosystem.

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