Occupational Exposure to Chlorinated Organic Solvents and its Effect on the Renal Excretion of N-Acetyl-Beta-D-Glucosaminidase

Abstract
Organic chlorinated hydrocarbon solvents are known to be nephrotoxic. However, very little is known about renal integrity after occupational exposure to these solvents. Increased urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion caused by necrosis of renal tubular cells can be used as a marker for nephropathy. In this study trichloroethylene (TRI), trichloroethane and freon 113 exposed persons from metal industries have been clinically investigated, and urine samples analysed for NAG activity and for trichloroacetic acid concentration. In order to analyse for possible subclinical kidney damage a group of diabetic patients with subclinical nephropathy served as positive controls. A significant higher NAG activity (p < 0.001) was found in the group of exposed workers as compared to the control group. About 10% of the exposed workers had an enhanced NAG value, corresponding to the level of diabetic patients with subclinical nephropathy. Increased NAG activity was observed in previously TRI-exposed persons, which might indicate induction of an autoimmune renal necrosis.