Trichloroethylene in urine as biological exposure index

Occupational exposure to trichloroethylene (TRI) was studied by analysis of environmental air and urine from 49 workers operating in a special printing house on glass. For the measurement of environmental concentration of TRI (C-env), the ambient air was sampled using personal passive dosimeters. The activated charcoal was desorbed with carbon disulfide and injected into a gascromatograph-mass spectrometer (GC-MSD). The biological monitoring of exposed workers was conducted by determining the concentration of TRI in urine (C-urine). Urine concentration of TRI was determined by headspace analysis using GC-MSD. Significant correlation was found between the environmental TRI concentration and urinary TRI concentration. The use of a regression equation between C-urine (mug/l) and C-env (mg/m(3)) (C-urine = 0.081 x C-env + 4.27) resulted in a value of C-urine corresponding to Threshold Limit Value-Time Weighted Average (TLV-TWA) exposure value (269 mg/m(3)) of 26.0 mug/L.