Occupational risk factors for renal-cell carcinoma in Denmark.

Abstract
Risk factors for renal-cell carcinoma, the most frequent type of kidney cancer, remains enigmatic. Time trends in incidence and changes in the regional distribution of this cancer are suggestive of environmental risk factors. This study reports on occupational risk factors for renal-cell carcinoma in Denmark. In a population-based study, 365 persons with histologically verified renal-cell carcinoma and 396 referents were interviewed. Information was collected on occupation, education, and occupational exposure to a number of suspected substances, including hydrocarbons, asbestos, and radiation. Risk of renal-cell carcinoma was found to be associated with employment as a truck driver, exposure to gasoline, other hydrocarbons, and insecticides and herbicides. The risk of renal-cell carcinoma was higher in the lower socioeconomic strata for both the men and the women. Nonsignificantly elevated risks were observed for employment in oil refineries, gasoline stations, and the iron and steel industry. No association was found for exposure to radiation or for employment in industries such as leather manufacturing and health care, which have previously been linked to an increased risk of renal-cell carcinoma. The risk of renal-cell carcinoma is increased in lower socioeconomic strata, and previously identified or suspected risk factors do not explain the excess in risk. This study adds additional support to the hypothesis of a link between renal-cell carcinoma and hydrocarbons and also demonstrates the need for further studies on occupational risk factors for renal-cell carcinoma.