Introduction: 2,4-Dichlorophenoxyacetic acid (2,4-D) is the most commonly used herbicide in the U.S. linked to adverse health outcomes and is a potential carcinogen. The relationship between 2,4-D and prostate cancer is unknown. Using a large, nationally representative survey of individuals in the United States, we investigated the relationship between 2,4-D exposure and prostate cancer. Methods: Data were leveraged from the National Health and Nutrition Examination (NHANES) Survey, which is a population-based cross-sectional study of men and women in the U.S, including biological specimen collection. Our cohort of interest was men aged 50 years and over. Urinary 2,4-D was used as a measure of exposure. Our primary outcome was history of prostate cancer based on individual reply of “yes” to either ever having prostate cancer or being treated for prostate cancer. Survey weights were applied to extrapolate estimates to the general at-risk male population in the United States. Chi-square, ANOVA, and multivariable, weighted logistic regression were used to analyze the relationship between 2,4-D and prostate cancer. Results: We identified 1,788 men, representing an estimated 691,709 men after survey weights were applied. Overall, the median 2,4-D level in urine was 0.28 mcg/mL (IQR 0.26 – 0.53). Within the total cohort, we observed a significant increased odds of prostate cancer for increasing exposure of 2,4-D (OR 1.02 95%CI [1.01,1.05]). Individuals in the highest quartile of 2,4-D exposure had a significantly increased odds of a prostate cancer diagnosis compared to the lowest quartile (OR=3.46 95%CI [1.11,10.72]). Stratification by age revealed significant associations between 2,4-D and prostate cancer in men age 70+ who were in the highest quartile of exposure (OR=3.79 95%CI[1.51,9.52]. Conclusions: These preliminary findings represent the first investigation of 2,4-D exposure and risk of prostate cancer. Future studies are warranted to corroborate these findings and elucidate potential mechanisms underlying these associations. SOURCE OF Funding: No sources of funding.
