Neoplastic changes in freshwater fishes: Correlation with oil refining

Traditionally, oil pollution has been viewed as single event, large scale disasters such as the Exxon Valdez spill in Alaska. However, it is becoming increasingly apparent that by products and anthropogenic contaminants resulting from oil exploration, extraction, recovery, refining, and the manufacture and use of oil and oil-based products are negatively impacting the environment. Potential problems of freshwater pollution by oil contaminants are increasing in many parts of the world from both active and abandoned oil production facilities. In the USA many ''Superfund'' sites have been designated for cleanup under the Comprehensive Environmental Response, Compensation and Liability Act of 1980; primarily because of waste discharged on to the sites by the oil industry. Pollution of surface and groundwater from these sites has already occurred and in some cases has led to deleterious effects on the complex aquatic and terrestrial ecosystems on and near these sites. The effect of oil and oil related products on aquatic organisms will be reviewed. Specifically, the discussion will focus on preneoplastic and neoplastic changes in fishes with a primary endpoint of cancer. Finally, a summary of current studies of feral fishes residing on and near an abandoned oil refinery in Oklahoma will be presented