[Cadmium exposure and health effects among residents in irrigation area with ore dressing wastewater].

About 0.05 mg Cd/L was found in the irrigation water contaminated by the wastewater discharged from the wolfram ore dressing plants, and about 1 mg Cd/kg was found in irrigated acid soil. The main sources of the cadmium intake by residents, living in pollution areas, were agricultural products. The average intake of cadmium was 366.7-381.9 micrograms/d, smokers 416.6 micrograms/d. Among residents, who have been exposed to cadmium for more than 25 years, cadmium absorption (CdU greater than or equal to 10 micrograms/g Cre) was 60% and early effect of target organ (CdU greater than or equal to 15 micrograms/g Cre and beta 2 -mU greater than or equal to 500 micrograms/g Cre) was 17%. Levels of CdU and CdB were beyond the critical value in the observation areas. The concentrations of CaU, beta 2-mU and NAGU were significantly higher among residents in observation areas compared with control areas. Owing to the combined cadmium effect the cases with fractional beta 2-m excretion greater than 0.10 were 46% in the observation areas, and it was much higher than that in control areas (20.3%) in a case-control study among residents who have been suffering from an original nephropathy with tubulo-interstitial abnormalities.