Pesticide contamination of private well water, a growing rural health concern

The Iowa Statewide Rural Well Water Survey (SWRL) was conducted between April 1988 and June 1989. SWRL was designed to provide a statistically valid assessment of the proportion of private rural wells and rural Iowa residents affected by various environmental contaminants. The survey was a systematic sample, stratified by rural population density. Approximately 14% of wells had detections of pesticides: 16 pesticide compounds (mostly herbicides) were detected, including 11 parent compounds and 5 environmental metabolites; 16 pesticides (mostly insecticides) were not detected. Atrazine and its metabolites were found in 8% of wells. Multiple residues were detected in all regions of the state. The mean concentrations were generally