The effects of temperature on polycyclic aromatic hydrocarbon (PAH) exposure and metabolism by fish

Ecological risk assessments (ERAs) for fish must take many factors into account in the comparison of laboratory and field studies when assessing perceived risk; one of these factors is water temperature. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants that pose a hazard to fish populations. Previous literature has indicated that temperature affects PAH availability, uptake, metabolism, and excretion. However, no predictable effect of temperature on PAH metabolism has been indicated, with increases, decreases, and no effect on metabolism being previously reported. The need for a proper understanding of the effect of temperature is critical for proper biomonitoring, ERAS, and comparative toxicological studies.; An initial study of the effect of temperature on ethoxyresorufin- o-deethylase (EROD) activity demonstrated that there was a compensation of activity at lower water temperatures. This effect was observed in both basal EROD induction as well as in PAH-exposed fish. However, the compensation did not occur instantaneously but over a 96 h period. Fish acclimated and exposed at lower temperatures had a slower initial rate of induction but after 96 h of exposure had a higher absolute EROD induction than those acclimated and exposed at a higher temperature. (Abstract shortened by UMI.)...