[Chronic bronchitis in workers producing iron-manganese alloys].

Out of 205 workers employed at production of iron-manganese alloys in 35.6% chronic bronchitis (CB) was found. In 11.1% CB occurred in non-smokers, and in 42.5% in cigarette smokers. The incidence of CB was increasing with the number of smoked cigarettes, and in the workers with smoking index < or = 10 it was 53.3% (smoking index = number of cigarette packs smoked daily (1 pack = 20 cigarettes) x number of smoking years). No influence of occupation environment was found on the incidence of CB in the studied workers.