We deployed semi-permeable membrane devices (SPMDs) on beaches in Prince William Sound (PWS), Alaska, to evaluate whether bioavailable contaminants from different pollution sources can induce cytochrome P450 1A (CYP1A) in biota. Deployment sites included canneries, salmon hatcheries, and beaches where lingering oil remains from discharges during the 1964 earthquake or the 1989 Exxon Valdez oil spill. Other sites were selected at random to evaluate region-wide contaminant inputs or were located in salmon streams to evaluate contaminants introduced into PWS by migrating salmon. Following ~28 d deployments, an aliquot of the accumulated contaminants was injected into juvenile rainbow trout (Oncorhynchus mykiss), and CYP1A activity measured by the ethoxyresorufin-o-deethylase (EROD) assay after 2 and 7 d. The oiled sites and one hatchery site with numerous creosote pilings elicited strong EROD responses, and the salmon streams elicited significant but weak responses during late summer compared to late spring. Responses from the other sites were not significant, indicating contaminants from these sources are unlikely to cause CYP1A induction in resident biota.