Abstract
Urinary .beta.2-microglobulin (.beta.2-m), .alpha.1-microglobulin (.alpha.1-m), amino-nitrogen, glucose, calcium, phosphorus, cadmium concentrations, and pH values were analyzed in urine samples from 187 females aged 55-66 years in the Jinzu River basin, which is known to be a cadmium-polluted area, and from 32 controls living in two adjacent reference areas in 1983-1984. Mean urinary .beta.2-m, .alpha.1-m, amino-nitrogen, glucose, cadmium concentrations and pH values in the inhabitants of the Jinzu River basin were significantly higher than those in the adjacent reference areas. Sixty-four inhabitants in a cadmium-polluted area were found to have rental tubular dysfunction with urinary .beta.2-m level exceeding 1 mg/g creatinine and urinary glucose level exceeding 100 mg/g creatinine. The severity of renal tubular dysfunction in several inhabitants were comparable to those of the patients with Itai-itai disease. Mean cadmium concentrations in rice (mean: 0.32-0.57 ppm) which has been daily consumed by the inhabitants of the Jinzu River basin were significantly higher than those in the reference areas (mean: 0.12-0.13 ppm). The close relationship between cadmium exposure and the degree of renal tubular dysfunction was well demonstrated by principal component analysis.