Auditory brainstem evoked potentials in asymptomatic lead-exposed subjects.

Auditory Brainstem Evoked Potentials (ABEP) were recorded from 29 adults and children, accidentally exposed to lead through food until approximately a year prior to this study. ABEP were recorded in response to 75 dBHL clicks presented at rates of 10/sec. and 55/sec. Average values were calculated for peak latency and for interpeak latency differences. Average values of the effect of increasing stimulus rate were calculated as well. Similar values were calculated for normative child and adult control groups. IPLD(I-III) showed the most significant and recurring results, with longer intervals in lead-exposed children compared with their control group. Increasing stimulus rate, on the other hand, affected the adult lead-exposed subjects more than the children. These results may imply an impairment of the peripheral portion of the auditory system with axonal and myelin involvement. ABEP is suggested as a sensitive detector of subclinical lead exposure effects on the nervous system.