NEUROBEHAVIORAL AND NEUROPHYSIOLOGICAL OUTCOMES OF ACUTE REPEATED PERCHLOROETHYLENE EXPOSURE

Two groups of male volunteers were exposed to 50ppm and 10ppm (controls) perchloroethylene (Per), respectively, for four h/day on four consecutive days. The higher of the two concentrations corresponds to the current MAK value for Per in Germany. A German version of the NES battery was given daily at the beginning and end of each experimental session; a pre-exposure baseline session was run before the first experimental test. Additionally, visual evoked potentials (VEPs) and brainstem auditory evoked potentials were recorded. Analysis of co-variance, with pre-exposure baseline values as co-variates, revealed significant performance deficits for vigilance and eye-hand coordination, as well as borderline prolongation of simple reaction times at elevated Per exposure, as compared to control conditions. A comparison of the two groups revealed a significant increase of the VEP peak latencies N75, P100 and N150 during the exposure to 50ppm Per as compared to the baseline values, whereas they tended to decrease in the control group. It is concluded that the "no adverse-effect level" for acute signs of CNS depression is below the current MAK value for Per.