NEUROPHYSIOLOGICAL FUNCTION IN FARM-WORKERS EXPOSED TO ORGANOPHOSPHATE PESTICIDES

To investigate neurophysiological effects of low-level exposure to fol iar organophosphate residues during one season among agricultural work ers, the authors performed a cross-sectional study of 67 Hispanic farm workers and 68 age-, gender-, ethnicity-, and education-matched refer ence subjects. The neurophysiological examination included sensory and motor nerve conduction and neuromuscular junction testing. Erythrocyt e cholinesterase activity was measured at the time of examination. No statistically significant neurophysiological differences between the e xposed and reference groups were observed. Farm workers and reference subjects had similar sensory nerve latency and amplitude (sural), moto r nerve conduction velocity (ulnar), and neuromuscular junction functi on (ulnar). No relationship between duration of exposure during the se ason and electrophysiological measures of nerve function was found. Ex posure of farm workers to the low levels of organophosphate pesticides during one season experienced by farm workers in this study was not a ssociated with impaired peripheral neurophysiological function.