Cancer incidence and community exposure to air emissions from petroleum and chemical plants in Contra Costa County, California: A critical epidemiological assessment

The northern part of Contra Costa County, California is heavily industrialized with a number of petroleum refineries, chemical facilities and other small industrial plants. Several epidemiological studies have been conducted in the country to assess cancer risk in relation to estimated air pollution levels. In this paper, the air monitoring data, air pollution modeling and the epidemiologic studies are critically reviewed. The association between cancer risk and estimated emissions is critically evaluated. The role of occupational and lifestyle (such as cigarette smoking and diet) confounding exposures is also assessed. The importance of validating exposure data generated by air pollution models in epidemiologic studies is emphasized. Pollutants of major concern are sulfur dioxide, nitrogen oxides, and hydrocarbons