Association Between Intake of Fruits and Vegetables by Pesticide Residue Status and Total Cancer Risk

Abstract

Abstract Objectives Intake of conventionally grown fruits and vegetables (FVs) is a primary route of exposure to pesticide residues in the general population. While occupational exposure to pesticides used in agriculture is known to be carcinogenic, it is unclear whether exposure to residues of these pesticides through diet carries comparable risks. To address this question, we evaluated the relation of FV intake, classified according to their pesticide residue status, with risk of cancer. Methods This prospective cohort study included 150,830 women (Nurses’ Health Study, 1998–2012, and Nurses’ Health Study II, 1999–2013) and 29,486 men (Health Professionals Follow-up Study, 1998–2012) who had no history of cancer. FV intake was ascertained using validated food frequency questionnaires. We categorized FVs as having high- or low-pesticide-residues using a validated scoring system based on pesticide surveillance data from the US Department of Agriculture. We used multivariate-adjusted Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) of total and site-specific cancer related to high- and low-pesticide-residue FV intake. Results A total of 18,969 incident cancer cases were documented during 1136,110 person-years of follow-up. In the pooled multivariable analysis, high-pesticide-residue FV intake was not significantly associated with cancer risk. The HR (95% CI) comparing individuals in increasing quintiles of high-residue FV intake to individuals in the lowest quintile were 0.99 (0.94, 1.04), 1.03 (0.98, 1.09), 0.98 (0.93, 1.04), and 1.00 (0.94, 1.06) (p, linear trend = 0.91). When specific sites were examined, we found no association between intake of high-pesticide-residue FVs and risk of any of the sites examined, including malignancies previously linked to occupational pesticide exposure. Similarly, intake of low-pesticide-residue FVs was unrelated to total or site-specific cancer risk. Conclusions These findings suggest that exposure to pesticide residues through intake of FVs at usual levels in the United States is not related to cancer risk despite well documented carcinogenesis in occupational settings. Funding Sources National Institutes of Health.