title: Tumor prevalence and biomarkers of exposure in brown bullheads (Ameiurus nebulosus) from the tidal Potomac River, USA, watershed.
abstract: Associations between contaminant exposure and liver and skin tumor prevalence were evaluated in brown bullheads (Ameiurus nebulosus) from the tidal Potomac River, USA, watershed. Thirty bullheads (> or = age 3) were collected from Quantico embayment, near a Superfund site that released organochlorine contaminants; Neabsco Creek, a tributary with petroleum inputs from runoff and marinas; and Anacostia River (spring and fall), an urban tributary designated as a Chesapeake Bay region of concern, that was contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and organochlorine pesticides. Fish were collected from the Tuckahoe River, as a reference. Cytochrome P450 activity, bile PAH metabolites, and muscle organochlorine pesticide and PCB concentrations were measured in randomly selected individuals and sediment contaminants were analyzed. We found statistically significant differences in liver tumor prevalences: Anacostia (spring), 50%; Anacostia (fall), 60%; Neabsco, 17%; Quantico, 7%; and Tuckahoe, 10%. Skin tumor prevalences were significantly different: Anacostia (spring), 37%; Anacostia (fall), 10%; Neabsco, 3%; Quantico, 3%; and Tuckahoe, 0%. Tumor prevalence in Anacostia bullheads warrants concern and was similar to those at highly contaminated sites in the Great Lakes. Evidence was found of higher PAH exposure in Anacostia fish but a cause-effect linkage could not be established. Fish tumor surveys, with histopathologic examination of internal and external organs, are recommended for monitoring the status of regions of concern.
authors.affiliation: U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, Maryland 21401, USA. fred_pinkney@fws.gov
authors.forename: A E
authors.initials: AE
authors.lastname: Pinkney
authors.forename: J C
authors.initials: JC
authors.lastname: Harshbarger
authors.forename: E B
authors.initials: EB
authors.lastname: May
authors.forename: M J
authors.initials: MJ
authors.lastname: Melancon
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor; D002273:Carcinogens / Q000032:analysis / Q000633:toxicity; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology / Q000662:veterinary; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D018281:Cholangiocarcinoma / Q000473:pathology; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005393:Fish Diseases / Q000139:chemically induced / Q000453:epidemiology*; D007059:Ictaluridae / Q000502:physiology*; D008113:Liver Neoplasms / Q000453:epidemiology / Q000662:veterinary; D016015:Logistic Models; D008396:Maryland; D009369:Neoplasms / Q000139:chemically induced / Q000453:epidemiology* / Q000662:veterinary*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000633:toxicity; D012878:Skin Neoplasms / Q000453:epidemiology / Q000662:veterinary; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D014408:Biomarkers, Tumor; D002273:Carcinogens; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D003577:Cytochrome P-450 Enzyme System; D019363:Cytochrome P-450 CYP1A1