8292265 Multiple pesticide exposure and prostate cancer risk in a cohort of agricultural workers

<h3>Objective</h3> The link between pesticides and prostate cancer risk has been studied in temperate regions and for specific substances. Few studies have examined multiple exposures in tropical environments, where pesticides are used more intensively. We aimed to investigate the role of occupational exposure to pesticide mixtures in prostate cancer incidence among banana workers in the French West Indies. <h3>Material and Methods</h3> The data come from a historical cohort study of 11,182 banana workers, followed for cancer incidence from 1981 to 2019. Exposure to 17 pesticides was assessed using a crop-exposure matrix. The study included 8,799 men with complete data on occupational exposure to pesticides and prostate cancer risk. Hierarchical Bayesian models were used to investigate the association between the risk of prostate cancer and occupational exposure to each pesticide, adjusting for the others, accounting for the strong correlations between pesticide exposures. Principal component analysis (PCA) and hierarchical clustering on PCA were used to define different exposure profiles and their potential role in prostate cancer risk was examined. The effect of a simultaneous increase of 25% in pesticide exposure levels was estimated by quantile g-computation. The analyses were adjusted for age and area of residence. <h3>Results</h3> Exposure to bitertanol, flusilazole, mineral oil and diquat were associated with an increase in prostate cancer risk, with adjustment for exposure to other pesticides. Four profiles of exposure were identified, and an elevated risk of prostate cancer was found among workers in profile 4, those with a very high exposure to all pesticides. A simultaneous increase in insecticides and herbicides levels increased the risk of prostate cancer. <h3>Conclusion</h3> The results suggest a deleterious effect of occupational exposure to a mixture of pesticides on the incidence of prostate cancer in banana workers in the French West Indies.