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

Environ Health Perspect. 2017 Jul 19;125(7):077013. doi: 10.1289/EHP793.

Abstract

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 (n=161) were compared with AHS cohort members without AMD (n=39,108). 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 [OR=2.7 (95% CI: 1.8, 4.0)] and organophosphate [OR=2.0 (95% CI: 1.3, 3.0)] insecticides and phenoxyacetate herbicides [OR=1.9 (95% CI: 1.2, 2.8)]. 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.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Aged
  • Aged, 80 and over
  • Agricultural Workers' Diseases / chemically induced
  • Agricultural Workers' Diseases / epidemiology*
  • Case-Control Studies
  • Female
  • Humans
  • Incidence
  • Iowa / epidemiology
  • Logistic Models
  • Macular Degeneration / chemically induced
  • Macular Degeneration / epidemiology*
  • Male
  • Middle Aged
  • North Carolina / epidemiology
  • Occupational Exposure
  • Pesticides / adverse effects*
  • Prospective Studies
  • Risk Factors

Substances

  • Pesticides