In situ biomonitoring of caged, juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Lower Duwamish Waterway

► Juvenile salmon were caged for 10 days in a river contaminated with PAHs and PCBs. ► Gill DNA adducts were elevated relative to hepatic adducts at two locations. ► FACs were comparable or higher than published levels detected in wild-caught fish. ► Results emphasize the importance of multi-year sampling in site characterization.