Both sides of tobacco leaves accumulate Po-210 through their sticky hairs (trichomes) by means of diffusive deposition. It is known that tobacco leaves may contain high amounts of Po-210 concentrations. However, there is less information about radionuclides in tobacco plants. In the study, the Po-210 concentrations were determined monthly in different morphological parts of tobacco plants (leaf, stem, root) and soil samples and soil-to-plant transfer factor for Po-210 was determined and the activity concentrations of Po-210 radionuclide in 16 different popular brands of cigarettes were investigated in order to estimate the annual effective doses of Po-210 to smokers. Besides the study investigated (focused on) the correlation between the amount of rainfall and Po-210 concentration of tobacco leaf. The results of the present study indicated that the activity concentration of Po-210 in cigarettes distributed in Turkey ranged from 16.1 +/- 1.0 to 37.6 +/- 2.6 mBq per cigarette and the mean value of their activity concentrations was 22.4 +/- 1.5 mBq per cigarette. The mean value of annual effective doses of Po-210 to smokers (20 cigarettes smoked by an individual per day) obtained from these activity concentrations was estimated to be 188.5 +/- 12.4 mu Sv y(-1).