STUDIES ON URINARY PROTEOGLYCAN EXCRETION IN OCCUPATIONAL CADMIUM EXPOSURE

Six foundrymen occupationally exposed to cadmium fumes excreted in ran dom urine samples 4.8+/-2.9 mug cadmium/g creatinine (+/-S.D.). Six co ntrols excreted 0.15+/-0.09 mug/g creatinine (+/-S.D.). The excretion of glycosaminoglycans by exposed men (2.3+/-1.1 mg/mmol creatinine, +/ -S.D.) did not differ from that of controls (2.3+/-1.6 mg/mmol, +/-S.D .). However, electrophoretic analysis of the isolated urinary proteogl ycan fraction revealed a dose-dependent progressive increase in the in tensity of two bands with a molecular weight between 45,000 and 50,000 . In control urines and in samples with urinary cadmium less than 3 mu g/g creatinine, only one major band with a molecular weight of 100,000 was detected. The changes may serve as early indicators of the harmfu l effects of cadmium on the proteoglycan-containing barriers of the ne phron.