Levels of cadmium (CdB) and lead (PbB) were determined in the blood of 579 60-65 year-old residents of Cologne and two small cities near Cologne. CdB-levels in cigarette smokers are on the average 3-4 times higher than in non-smokers (geometric means: non-smokers, 0.44 micrograms/l; less than or equal to 10 cigarettes/d, 1.16 micrograms/l; greater than 10 cigarettes/d, 1.85 micrograms/l). The results indicate that, with regard to the internal dose, cadmium exposure via smoking may contribute even more than does exposure via food. PbB-levels (geometric mean: 8.49 micrograms/100 ml; range: 2.9-30.3 micrograms/100 ml) are in the acceptable range as defined by the CEC reference values. Male smokers have on the average slightly higher PbB-levels than male non-smokers. In women PbB-levels are on the average lower than in men.