Abstract: This study compared the neuropsychological performance of a group of 29 workers occupationally exposed to low level of toluene(8 hours TWA=88.0 ppm)with a control group(N=29)not exposed to toluene(8 hours TWA=13.5ppm).The psychological tests consisted of Digit Span,Visual Reproduction of WMS,Benton Visual Retention Test,Trail-Making Test,Symbol-Digit Modality Test,Grooved Pegboard Test,and Finger Tapping Test.Results of the study showed that the performance of the exposed workers were poorer than the control subjects in verbal and nonverbal short term memory,attention and concentration,perceptual-motor function,and finger dexterity.These findings suggested that the brain functions of the exposed workers were significantly deteriorated. The findings also confirmed the usefulness of psychological tests in the detection of neurotoxic effects of occupational exposure to low level of toluene.

Key words: psychological test, toluene, solvent, brain function