Technical Services Study/Fish Histopathology Damage Assessment after the Exxon Valdez Oil Spill
Tissue samples from 4 fish species examined for microscopic lesions after the Exxon Valdez oil spill revealed that fishes in Prince William Sound were significantly affected by the oil spill. In Dolly Varden char, hepatic lipidosis and megalocytosis were the major histopathologic markers separating exposed from reference sites. In adult herring in 1989, hepatocellular necrosis occurred in fish from exposed sites only. In larval herring in 1989, ascites prevalence was significantly greater in fish from oiled sites. Adult pink salmon had no lesions significantly related to oil exposure. Larval and juvenile pink salmon had few lesions; those most likely related to oil exposure were renal tubular necrosis and vascular thrombosis. In rockfish species from 1990 and 1991, hepatocellular lipidosis and macrophage aggregates in the liver, spleen, and kidney were the major histopathologic markers separating exposed from reference sites; based on lack of documented exposure, however, these probably resulted from site differences other than oil exposure.
