Pesticide Use and Age-Related Macular Degeneration in the Agricultural Health Study

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of blindness in developed countries. Few studies have investigated its relationship to environmental neurotoxicants. In previous cross-sectional studies, we found an association between pesticide use and self-reported retinal degeneration. OBJECTIVE: We evaluated the association of pesticide use with physician-confirmed incident AMD. METHODS: The Agricultural Health Study (AHS) is a prospective cohort of pesticide applicators and their spouses enrolled from 1993–1997 in Iowa and North Carolina. Cohort members reported lifetime use of 50 specific pesticides at enrollment. Self-reports of incident AMD during follow-up through 2007 were confirmed by reports from participants’ physicians and by independent evaluation of retinal photographs provided by the physicians. Confirmed cases ([Formula: see text]) were compared with AHS cohort members without AMD ([Formula: see text]). We estimated odds ratios (ORs) and 95% confidence intervals (CIs) by logistic regression with adjustment for age, gender, and smoking. RESULTS: AMD was associated with ever use of organochlorine [[Formula: see text] (95% [Formula: see text])] and organophosphate [[Formula: see text] (95% CI: 1.3, 3.0)] insecticides and phenoxyacetate herbicides [[Formula: see text] (95% [Formula: see text])]. Specific pesticides consistently associated with AMD included chlordane, dichlorodiphenyltrichloroethane (DDT), malathion, and captan; others with notable but slightly less consistent associations were heptachlor, diazinon, phorate, 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), and 2,4-dichlorophenoxyacetic acid (2,4-D). Results were similar for men and women. Some specific pesticides were associated with both early- and late-stage AMD, but others were associated with only one stage. CONCLUSIONS: Exposures to specific pesticides may be modifiable risk factors for AMD. https://doi.org/10.1289/EHP793