The cadmium concentration of renal tissue from 120 patients, who had died at the age of 45-65 years, has been determined by atomic absorption spectrophotometry. The concentration did not differ significantly either between urban and rural dwellers or between male and female subjects. The concentration of cadmium in kidneys from cigarette smokers was about twice as high as in kidneys from non-smokers. Renal cadmium concentration was higher in normotensives than in hypertensives. When smoking habits were taken into account, renal cadmium concentration was found to be 82% higher in normotensives than in hypertensives. The possible roles of water hardness and selenium intake are discussed.