Prostate cancer in pesticide applicators in Swedish agriculture

BACKGROUND: The use of chemicals in agriculture has been associated with elevated risks of prostate cancer. The aim of this study was to analyze prostate cancer risk in a cohort of 20,025 pesticide applicators in agriculture licensed between 1965-1976. METHODS: The cohort was followed up in the Swedish Cancer Register from date of licence until death of December 31, 1991. The mean follow-up time was 21.3 years. RESULTS: We found a statistically significant increased risk of prostate cancer with 401 cases observed compared to 355 expected, with a standardized incidence ratio (SIR) of 1.13 (95% confidence interval: 1.02-1.24). There were 7 cases among those born in 1935 or later, and the SIR was 2.03 (0.82-4.19). For those born earlier than 1935 the SIR was 1.12 (1.01-1.24). CONCLUSIONS: These findings of a statistically significant increased risk of prostate cancer, together with recent results from other studies, imply a relationship between agrochemicals or other risk factors in the environment of farmers and prostate cancer.