[Etiology of bronchial cancer: smoking, passive smoking, environment and occupation].

The inhaled tobacco smoke is the most important determinant in the etiology of lung cancer and there is a clear dose-effect relation between lung cancer risk and the duration of smoking, the number of cigarettes and the intensity of inhalation. The opinions about lung cancer risk from passive smoking are divided and the published data are still in discussion. Occupational substances include chromates, nickel, beryllium, alkylated compounds, vinylchloride, arsenic compounds and in particular asbestos. Fortunately air pollution has no or small part in the etiology of lung cancer.