Great Lakes Environmental Research Laboratory
Distinguished Scientist Seminar Series

Dr. Robert J. Letcher
Great Lakes Institute for Environmental Research (GLIER)
and Department of Chemistry and Biochemistry
University of Windsor
Windsor, Ontario, Canada

"Methyl Sulfone and hydroxylated metabolites
of polychlorinated biphenyls in marine wildlife
and their endocrine disruption potential"



    Location: Great Lakes Environmental Research Laboratory
              4840 S. State Rd.
              Ann Arbor, MI  48108-9719
        Date: Wednesday, January 10th, 2001
        Time: 10:30-11:30 am
        Room: 105 (Main Conference Room)

ABSTRACT: Methyl sulfone (MeSO2-) metabolites of polychlorinated biphenyls (PCBs) are persistent and bioaccumulate in biota. These PCB metabolites have emerged as an important class of environmental contaminants in humans, a growing number of marine and terrestrial mammals and some bird species. Hydroxylated (HO-) PCB metabolites are retained in the blood and plasma and have been determined in humans and a limited number of wildlife species. Furthermore, these metabolites are useful biomarkers of the role of metabolism in the toxicokinetics of PCB exposure. Recent in vitro and in vivo bioassay screening have indicated that persistent MeSO2-PCBs and retained OH-PCBs are potentially thyroidogenic and (anti)estrogenic in wildlife and humans. Therefore, the endocrine activity of PCBs in vivo are likely mediated, in part, by PCB metabolites. This presentation will discuss and summarize existing and new information on the levels, congener patterns and nature of MeSO2-PCB and HO-PCB metabolites in marine-related wildlife species. The known thyroidogenic and (anti)estrogenic activity in vitro and in vivo of persistent MeSO2-PCBs and retained OH-PCBs is also discussed to evaluate their potential as endocrine disrupting agents in wildlife and humans.


For further information, please contact:

David F. Reid
NOAA Great Lakes Environmental Research Laboratory
4840 S. State Rd.
Ann Arbor, MI 48108-9719
734-741-2019
reid@glerl.noaa.gov

http://www.glerl.noaa.gov/news/seminars/2001/letcher.html