TRICHLOROETHYLENE EXPOSURE IN VAPOR DEGREASING AND THE URINARY-EXCRETION OF N-ACETYL-BETA-D-GLUCOSAMINIDASE

In order to elucidate the potential nephrotoxicity of low level occupational exposure to trichloroethylene (TRI), urine analysis of the tubular enzyme N-acetyl-beta-D-glucosaminidase (U-NAG) was included in a cross-sectional study of metal degreasers in central Sweden. Eighty-six percent of 8-h TRI in air measurements were well below 50 mg/m3. Normal levels of NAG were found in morning urine samples from 29 workers compared to a historical reference group. A weak positive correlation (r = 0.48; P <0.01) was observed between U-NAG activity and the concentration of the TRI metabolite trichloroacetic acid in urine but not with other estimates of recent or long-term exposure. In conclusion, TRI does not seem to be nephrotoxic at low exposure levels.