Pancreatic cancer is a rapidly fatal disease that has been linked with
pesticide use. Previous studies have reported excess risks of
pancreatic cancer with organochlorines such as
DDT, however, many other commonly used pesticides have not been examined. To further examine the potential associations between the use of a number of pesticides and
pancreatic cancer, we conducted a case-control analysis in the Agricultural Health Study, one of the largest prospective cohorts with over 89,000 participants including
pesticide applicators and their spouses in Iowa and North Carolina. This analysis included 93 incident
pancreatic cancer cases (64 applicators, 29 spouses) and 82,503
cancer-free controls who completed an enrollment questionnaire providing detailed
pesticide use, demographic and lifestyle information. Ever use of 24 pesticides and intensity-weighted lifetime days [(lifetime exposure days) x (exposure intensity score)] of 13 pesticides was assessed. Risk estimates were calculated using unconditional logistic regression controlling for age, smoking, and diabetes. Among
pesticide applicators, 2
herbicides (
EPTC and
pendimethalin) of the 13 pesticides examined for intensity-weighted lifetime use showed a statistically significant exposure-response association with
pancreatic cancer. Applicators in the top half of lifetime
pendimethalin use had a 3.0-fold (95% CI 1.3-7.2, p-trend = 0.01) risk compared with never users, and those in the top half of lifetime
EPTC use had a 2.56-fold (95% CI = 1.1-5.4, p-trend = 0.01) risk compared with never users. Organochlorines were not associated with an excess risk of
pancreatic cancer in this study. These findings suggest that
herbicides, particularly
pendimethalin and
EPTC, may be associated with
pancreatic cancer.