Association between diesel exposure at work and prostate cancer

Objectives The possible etiologic relevance of occupational factors such as cadmium, cutting oils, diesel fuel and fumes, herbicides, polycyclic aroma tic hydrocarbons (PAH), polychlorinated biphenyls, soot, tar, mineral oil, and solvents to prostate cancer was studied. Methods A case-referent study design was used to recruit 192 subjects with histologically confirmed prostate cancer and 210 referents who had prostate cancer histologically excluded either in one of two urologic practices (Ha mburg and Frankfurt) or in the urological policlinic of the Frankfurt Unive rsity. Data were gathered with a self-administered questionnaire and analyz ed using logistic regression to control far age, region, and cigarette smok ing. A job-exposure matrix was used for assigning exposure. For the calcula tion of dose-yeats, the duration of contact with specific substances was we ighted by the intensity and probability of exposure according to a job expo sure matrix. Results The analysis of dose-years yielded a statistically significant asso ciation between occupational exposure to diesel fuel or fumes and prostate cancer (odds ratio 3.7, 95% confidence interval 1.4-9.8, for subjects expos ed to more than 25 dose-years in a comparison with subjects never exposed). For the other substances, no statistically significant differences in expo sure were found between the cases and referents. When only jobs with a high exposure probability were used to classify the participants as exposed, on ly exposure to PAH was significantly associated with prostate cancer. Conclusions In keeping with results from other studies, this study provides further evidence that exposure to diesel fuel or fumes - possibly mediated through PAH - may be associated with the development of prostate cancer.