Epidemiological survey of workers exposed to inorganic germanium compounds

Objectives-To assess occupational exposure to inorganic germanium (Ge) in w orkers from a producing plant, and to assess the health of these workers, w ith a special focus on respiratory, kidney, and liver functions. Methods-Cross sectional study of 75 workers exposed to Ge and 79 matched re ferents. Exposure was characterised by measuring air and urine concentratio ns of the element during a typical working week, and health was assessed by a questionnaire, clinical examination, lung function testing, chest radiog raphy, and clinical chemistry in serum and urine, including high and low mo lecular weight urinary proteins. Results-Airborne concentrations of Ge (inhalable fraction) ranged from 0.03 to 300 mu g/m, which was reflected by increased urinary excretion of Ge (0 .12-200 mu g/g creatinine, after the shift at the end of the working week). Lung, liver, and haematological variables were not significantly different between referents and workers exposed to Ge. A slightly higher urinary con centration of high molecular weight proteins (albumin and transferrin) was found in workers exposed to Ge, possibly reflecting subclinical glomerular changes. No relation was found between the intensity or duration of exposur e and the urinary concentration of albumin. No difference between referents and workers exposed to Ge was found for other renal variables. Conclusions-Measurement of urinary Ge can detect occupational exposure to i norganic Ge and its compounds. It is prudent to recommend the monitoring of renal variables in workers exposed to Ge.