PESTICIDE EXPOSURE AND END-STAGE RENAL DISEASE AMONG PESTICIDE APPLICATORS AND THEIR SPOUSES IN THE AGRICULTURAL HEALTH STUDY

Abstract

Experimental studies suggest a relationship between pesticide exposure and renal impairment, but epidemiological research on the long-term effects of chronic low-level and acute pesticide exposure on renal disease risk is limited. This study investigated the relationship between end-stage renal disease (ESRD) risk and 1) long-term use of and exposure to specific pesticides; 2) short-term high-level pesticide exposures; and 3) farming and household factors that may increase exposure to pesticides, among male licensed pesticide applicators (N=55,580) and their wives (N=32,099) in the Agricultural Health Study (AHS). AHS participants reported pesticide use and exposure via self-administered questionnaires at enrollment (1993-1997). Associations between ESRD and pesticide exposures were estimated with Cox proportional hazard regression models controlling for age at enrollment, state of enrollment (applicator analyses only), and personal use of any pesticide (wives analyses only). ESRD cases were identified via linkage to the United States Renal Data System (USRDS). Standardized incidence ratios (SIRs) were calculated to compare ESRD incidence rates in the AHS cohort to the general population. We identified 320 and 103 ESRD cases diagnosed between enrollment and 31 December 2011 among pesticide applicators and wives, respectively. Among applicators, ESRD risk was elevated with use of the fungicide metalaxyl, and the herbicides imazethapyr, paraquat, and petroleum oil, with positive exposure-response trends observed for paraquat, pendimethalin, and the insecticide chlordane. Medical visits due to pesticide use were associated with ESRD. Among wives who never applied pesticides, ESRD risk was significantly associated with husbands' ever use of paraquat and butylate, with a positive exposure-response trend observed for husband's cumulative use of these pesticides. Positive associations were observed with private well proximity to pesticide mixing areas, washing pesticide-exposed clothing with the family wash, and spending >10 hours in the sun during the growing season, though estimates were imprecise. ESRD incidence rates were lower among applicators and wives compared to the general population. Our findings support a possible association between ESRD risk and chronic exposure (both direct and indirect) to certain pesticides and suggest that pesticide exposures resulting in medical visits may increase the risk of incident ESRD.Doctor of Philosoph