MASS-SPECTROMETRIC ANALYSIS FOR AROMATIC-COMPOUNDS IN BILE OF FISH SAMPLED AFTER THE EXXON-VALDEZ OIL-SPILL

After the Exxon Valdez oil spill, the exposure of marine organisms to petroleum had to be determined. Gas chromatography/mass spectrometry was used to identify metabolites of aromatic compounds (ACs), such as alkylated naphthols, phenanthrols, and dibenzothiophenols, in the hydrolyzed bile of five salmon (Oncorhynchus gorbuscha) and four pollock (Theragra chalcogramma) captured in Prince William Sound several months after the oil spill. These metabolites were not found in control fish sampled from areas not impacted by the oil. The metabolites were identified by comparison to those from the hydrolyzed bile of a halibut (Hippoglossus stenolepis) which had been injected with weathered Prudhoe Bay crude oil. The dibenzothiophenols are proposed as promising marker compounds for identifying the exposure of fish to certain crude oils. In addition, a high-performance liquid chromatographic method to screen bile for metabolites of ACs was validated for use in estimating the exposure of fish to petroleum.