Metabolites of Aromatic Hydrocarbons in the Bile of Brown Bullheads (Ictalurus nebulosus)

Abstract

In vivo metabolism and biliary excretion of PAH by brown bullheads was determined using an HPLC/fluorescence method. In laboratory studies, 24 hours after feeding of PAH, bullheads had evidence for polar metabolites of the PAH in their bile as detected by HPLC’/fluorescence. These materials were detectable only at wavelengths specific for the compound that was fed. Analysis of bile from wild bullheads collected from areas with varying degrees of pollution demonstrated that bullheads from the Buffalo River had benzo[a]pyrene equivalents that were 7–148 times greater than those found in fish from less polluted areas. Similarly, levels of phenanthrene equivalents were 7–297 times greater in Buffalo River fish when compared to the other sites. These studies indicate that bullheads can rapidly metabolize dietary PAH, and wild bullheads from industrially impacted waterways such as the Buffalo River are receiving significant PAH exposure. This PAH exposure may account, in part, for the increased incidence of neoplasia observed in the bullheads.