Original Contribution Occupational Exposure to Pesticides and Risk of Non-Hodgkin’s Lymphoma

Pesticide exposure may be a risk factor for non-Hodgkin’s lymphoma, but it is not certain which types of pesticides are involved. A population-based case-control study was undertaken in 2000–2001 using detailed methods of assessing occupational pesticide exposure. Cases with incident non-Hodgkin’s lymphoma in two Australian states (n 694) and controls (n 694) were chosen from Australian electoral rolls. Logistic regression was used to estimate the risks of non-Hodgkin’s lymphoma associated with exposure to subgroups of pesticides after adjustment for age, sex, ethnic origin, and residence. Approximately 10 % of cases and controls had incurred pesticide exposure. Substantial exposure to any pesticide was associated with a trebling of the risk of non-Hodgkin’s lymphoma (odds ratio 3.09, 95 % confidence interval: 1.42, 6.70). Subjects with substantial exposure to organochlorines, organophosphates, and ‘‘other pesticides’ ’ (all other pesticides excluding herbicides) and herbicides other than phenoxy herbicides had similarly increased risks, although the increase was statistically significant only for ‘‘other pesticides.’ ’ None of the exposure metrics (probability, level, frequency, duration, or years of exposure) were associated with non-Hodgkin’s lymphoma. Analyses of the major World Health Organization subtypes of non-Hodgkin’s lymphoma suggested a stronger effect for follicular lymphoma. These increases in risk of non-Hodgkin’s lymphoma with substantial occupational pesticide exposure are consistent with previous work. case-control studies; herbicides; lymphoma, non-Hodgkin; occupational exposure; pesticide