[Clinical symptoms and findings in the lower airways of soot-exposed workers].

Eighty three still exposed and 46 formerly exposed workers, exposed especially to dust of carbon black and extreme heat climate conditions up to 2 and 30 years, were asked using a standardized questionnaire concerning complaints of the lower airways. The workers were investigated clinically, by X-rays and functionally to find out disturbances of health in the lower airways. The sputum was investigated cytologically. Moreover, the certificates of death were checked. The results were compared to those of 144 control persons living in the same region. The still exposed and the formerly exposed workers were suffering from chronic bronchitis, from non-specific bronchial hyperreactivity and from obstructive ventilatory disturbances in dependence on the duration of exposition more frequently than the control persons. But the mean values of the one-second value of forced expiratory volume in per cent of the vital capacity of every group were not different. Severe disturbances of the lung function were stated in some cases mostly exposed more than 20 years. On 3 workers, exposed more than 20 years, roentgenological signs of a pneumoconiosis were diagnosed demonstrating the fibrogenic effect of carbon black. The cytological findings of sputum didn't show any new aspects. Compared to the other people no deviating frequencies of causes of death were found, especially not more cases with neoplasma. The mostly less frequencies of symptoms and findings of the formally exposed workers were estimated as a hint for regression of the disturbance. The expected dependence of the signs on smoking habits was not recognized. So the exposition described was emphasized as a professional noxious factor, particularly as compared to the control persons important differences were found and the influence of the duration of exposition on the symptoms and findings was significant. Workers exposed to soot suffering from chronic bronchitis, nonspecific hyperreactivity, and especially obstructive ventilatory disturbances should be held in pulmonary dispensary in time.