Cognitive evoked potentials VEP P300 persons occupationally exposed to low concentrations of toluene.

Cognitive evoked potentials VEP P300 were examined in 49 workers at printing press occupationally exposed to low concentrations of toluene for averagely 20 years, and in 59 control subjects. The exposure level of toluene was evaluated in randomly selected subgroups comprising 36 exposed and 27 control subjects. The concentrations of toluene were measured in peripheral blood on Wednesday morning before entering the work area, while the hippuric acid in urine was measured before and after entering the work area. The results show that the absolute number of exposed subjects displaying lower amplitude of cognitive wave VEP P300R and prolonged latency of the accompanying spontaneous wave VEP P300F was significantly greater than that of the controls.