PARENT SESSION
PW7 - Biotransformation / Metabolisms / Degradation
Wednesday, 20 November 2002
8:00 AM to 6:30 PM
Exhibit Hall

(P801) Phenolic PCB metabolites and other polyhalogenated phenolics in fish from the Detroit River.

Li, Hongxia^*,1, Bennett, Erin¹, Drouillard, Ken¹, Haffner, Douglas¹, Letcher, Robert¹, ¹ Great Lakes Institute for Environmental Research, University of Windsor, Windsor, Ontario, Canada

ABSTRACT- Benthic and pelagic fish species in the Detroit River contain some of the highest PCB and organochlorine concentrations relative to other populations in the Great Lakes system. PCBs and octachlorostyrene (OCS), have been shown to be biotransformed to phenolic (OH) metabolites and retained in the blood of mainly aquatic mammalian species, whereas such studies in fish are extremely limited. In the present study, PCBs, OCs (DDTs, chlordanes, HCH and OCS), phenolic PCB and OC metabolites, and pentachlorophenol (PCP) were determined and compared in the plasma from 2 pelagic and 3 benthic fish species that were collected from areas in the upper Detroit River. In largemouth bass (Micropterus salmoides), northern pike (Esox lucius), brown bullhead (Ameiurus nebulosus), common carp (Cyprinus carpio) and white sucker (Catostomus commersoni), despite variations in species and sampling location, the -PCB (38 to 210 ng/g, wet weight), -chlordane (1 to 8 ng/g, wet weight) and -DDT (4 to 26 ng/g, wet weight) concentrations were comparable. Variable numbers of OH-PCB congeners (-OH-PCBs, 0.5 to 3 ng/g, wet weight) were identified and quantified in all species. PCP (0.1 to 3.5 ng/g, wet weight) was also present in all species, whereas the supposed OCS metabolite, 4-OH-heptachlorostyrene (4-OH-HpCS, 0.08 to 0.18 ng/g. wet weight) was detectable in all species except the northern pike. In all the fish studied, cytochrome P450 enzyme capacity to metabolize PCB congeners and OCS is indicated, as well as the capacity to retain these phenolic metabolites in the blood. Knowledge of phenolic metabolites is important to understand the influence and importance of metabolism in the fate and toxicokinetics of PCBs and OCs. Furthermore, OH-PCBs and 4-OH-HpCS are capable of endocrine disrupting activity, and their presence may be impacting the reproductive and developmental health of Detroit River fish.

Key words: Phenolics, PCB, Benthic fish, Pelagic fish