[Epidemiology of chronic bronchitis from the viewpoint of occupational medicine].

In a comprehensive epidemiological study the influence of age, smoking and exposure to dust upon the prevalence of chronic bronchitis could be confirmed and quantified. From the quantified contributing factors it is evident that chronic bronchitis after exposure to dust cannot generally be declared as occupational disease. The relative risk of heavy smokers of 1,9 is of the same order as the relative risk after 20 years' exposure to dust. Individual measures of health control and health care are necessary and should be intensified after 10 years of exposure.