EARLY DIAGNOSIS OF N-HEXANE-CAUSED NEUROPATHY

n-Hexane neuropathy was studied in 20 workers exposed for prolonged pe riods to this solvent, and with urinary 2,5-hexanedione concentrations exceeding the biological exposure index recommended by the American C onference of Governmental Industrial Hygienists (5 mg/L) with a mean o f 11.02 mg/L (range 5.3-24.2 mg/L). Although neurological examination did not detect significant anomalies in any of the patients, and the c onduction velocity and F waves of all the nerves tested were normal, n eurographic studies revealed significant differences in the amplitude of sensory nerve action potentials (SNAP) recorded from the sural (mea n 14.0 mu V), median (mean 17.3 mu V), and ulnar (mean 7.9 mu V) nerve s when compared with normal values from healthy adults of the same age range, examined under identical conditions. The amplitude of the SNAP in sural and median nerves correlated significantly with the number o f years worked. The notable decrease in mean amplitude of the SNAP app eared to reflect the primary neurotoxic effects of 2,5-hexanedione. (C ) 1994 John Wiley and Sons, Inc.