TITLE: Biochemical responses to sediment-associated contaminants in brown bullhead (Ameriurus nebulosus) from the Niagara River ecosystem

JOURNAL: Ecotoxicology
VOLUME: 06
ISSUE: 01
PAGES: 0013-0034

AUTHOR: NANCY A. EUFEMIA, TRACY K. COLLIER, JOHN E. STEIN, DAVID E. WATSON, RICHARD T. DI GIULIO

ADDRESS: Ecotoxicology Laboratory, School of the Environment, Duke University, Durham, NC 27708-0328 USA. Environmental Conservation Division, Northwest Fisheries Science Center, National Marine Fisheries Service, 2725 Montlake Boulevard East, Seattle, WA 98112-2097 USA. Ecotoxicology Laboratory, School of the Environment, Duke University, Durham, NC 27708-0328 USA

ABSTRACT: Brown bullhead (Ameriurus nebulosus) were collected from three sites in the Niagara River ecosystem in June and September of 1991, and sediment samples from these sites were obtained in July 1991. The sites were located inthe Buffalo River, the Niagara River adjacent to the Love Canal dump site, and in Black Creek, a Canadian tributary of the Niagara River which served as a reference site. Sediment samples from these sites contained measurable concentrations of various polycyclic aromatic hydrocarbons (PAHs) and chlorinated hydrocarbons (CHs). However, the Buffalo River and Love Canal samples were significantly more contaminated than those from Black Creek. Moreover, Buffalo River samples contained greater PAH concentrations than samples from the Love Canal, while the reverse was observed for CHs. Bile and liver of bullhead were used for the following analyses: fluorescent aromatic compounds in bile, a measure of exposure to PAHs, microsomal cytochrome P450 (CYP) and P450IA (CYP1A) contents and ethoxyresorufin-O-deethylase (EROD) activities, total glutathione (TH-GSH) concentrations, concentrations of 8-oxodeoxyguanosine (8-oxo-dG), and concentrations of hydrophobic DNA adducts (as measured by 32P-postlabelling). Additionally, a laboratory experiment was performed to examine CYP1A-associated responses in bullhead exposed to the model inducer, β-naphthoflavone (BNF). Results from the laboratory induction study were generally consistent with those observed in the field study, but the field study results suggested induction of CYP1A in bullhead from the reference site (Black Creek). For both field collections, fish from the Buffalo River displayed the greatest concentrations of fluorescent compounds in bile and hepatic DNA adducts, whilst fish from the Love Canal site displayed the greatest microsomal CYP1A concentrations and EROD activities. TH-GSH concentrations were significantly greater in Buffalo River fish versus Black Creek only for the June sampling. No statistically significant differences in 8-oxo-dG concentrations in bullhead hepatic DNA were observed among the sites at either sampling date. The different patterns in biochemical responses observed were consistent with sediment chemistries, and these resultssuggest that exposure of feral teleosts to different suites of bioavailable contaminants can be associated with expression of a characteristic array of biochemical responses

KEYWORDS: Ameriurus