The risk of lung cancer associated with occupational cadmium (7440439) exposure was examined. Data from a 1976 NIOSH study of mortality among 606 white male workers at a cadmium smelter and follow up studies conducted through 1984 were utilized. The data were analyzed by modified life table analysis techniques to estimate the standardized mortality ratios (SMRs), and by Poisson and Cox proportionate hazard regression models to evaluate the dose response relationships. The cohort showed an overall excess of lung cancer mortality (SMR 149). When stratified according to ethnicity, lung cancer mortality was highest among nonHispanic workers (SMR 211). When analyzed according to exposure category, lung cancer mortality was highest among workers with the highest cadmium exposures and workers who had been employed at the facility for at least 20 years; SMRs were 272 and 161, respectively. The Poisson and Cox models indicated that the risk of lung cancer increased with increasing cadmium exposure, from 1.2 to 205.2 and from 0.5 to 96.4 cases per 1000 workers, respectively. The authors conclude that, based on these data, a lifetime lung cancer risk of 50 to 111 cases/1000 can be estimated if the current OSHA standard for cadmium (100 micrograms per cubic meter) is adhered to.