Occupational exposure to tetrachloroethene and its effects on the kidneys

Occupational exposure to tetrachloroethene (TCE) has been reported to cause early adverse effects on the kidneys. We investigated the effects of TCE exposure on the kidneys in 82 exposed and 19 nonexposed workers from four dry-cleaning shops in The Netherlands. The mean inhaled amount of TCE in the exposed group, which was assessed by determination of its concentration in alveolar air samples, was 8.4 mg/m3 (range, 2.2-44.6 mg/m3). This value corresponds to a mean 8-hour time-weighted average exposure of 7.9 mg/m3 (range, 1-221 mg/m3). A chronic dose index (CDI) was estimated from data on the current TCE dose and the occupational history of the individual subjects. The mean CDI in the exposed group was 400 months X mg/m3 (range, 12-4882 months X mg/m3). Effects on the tubules were assessed with the parameters N-acetyl-beta-D-glucosaminidase, beta-galactosidase, alanine aminopeptidase, and retinol-binding protein (RBP) in urine. Early effects on the glomeruli were monitored with the parameter albumin in urine. Total protein in urine was determined for the general assessment of effects on the glomeruli and tubules. The tubular parameter RBP was increased in the exposed group, compared with the nonexposed group. None of the other parameters differed between the study groups, and none of the renal-effect parameters correlated with the TCE dose or the CDI. In conclusion, occupational exposure to TCE may cause a minor effect on the tubular RBP at exposure levels below the Dutch occupational exposure limit (240 mg/m3).