[The combined effect of ionizing radiation and smoking on the causation of bronchial carcinoma (author's transl)].

For the prevention of bronchial carcinoma the identification of its causes is of highest priority. Especial attention should be dedicated to the combined action of several factors. In this paper a review is given on the combination effect of simultaneous action of ionizing radiation and smoking observed by epidemiological studies in miners exposed to radon and its consecutive products. The amplifying action of both factors observed under working conditions brought about to refer to such combinations in smokers also outside their working life. This results from the natural loading by radiation of the respiratory tract, from radioactive material in the emmission of power stations on the base of fossil fuels, and from the contents of tobacco with 210Pb and 210Po. The combined action of radiation and smoking is regarded as another motivation to give up smoking strictly.