[Detection of early kidney damage in workers exposed to lead, mercury, and cadmium (author's transl)].

Our study was performed to evaluate potential adverse effects on the kidney caused by an occupational exposure to cadmium, lead, and mercury, respectively. We examined 81 individuals of a Zn-Cd-plant and of a Ni-Cd-battery factory, occupationally exposed to cadmium. In a chemical company, synthesizing mercury-compounds, we analyzed 23 exposed workers. The 21 persons with an exposure to lead were employed in a secondary lead smelting plant. To evaluate the degree of the occupational exposure we analyzed the concentrations of the heavy metals in blood and urine samples. As indicators of an adverse effect on the kidney the renal elimination of specific proteins was determined. The analysis of proteins with a higher molecular weight, such as albumine and acid alpha 1-glycoproteine, was performed using a new developed laser nephelometric method. Patterns of renal eliminated proteins with a lower molecular weight were characterized applying radio immunological determination of beta 2-microglobuline. The results found in workers exposed to cadmium verified previous studies. The occurrence of a characteristic beta 2-microglobulinuria takes place after a sufficient long period of exposure. In addition to this, cadmium exposed workers had an increased elimination of total proteine. Persons with an exposure to mercury also showed a slightly increased elimination of beta 3-microglobuline and total proteine. An intensive long exposure to mercury and its (in-) organic compounds seems to induce an increased renal elimination of proteins. No increased renal elimination was found in persons occupationally exposed to lead.