Distribuzione della pneumoconiosi e della bronchite cronica negli addetti alla produzione del cemento.

An examination of 318 cement workers was carried out to evaluate the prevalence rate of pneumoconiosis and chronic bronchitis. In 7.2% of the exposed workers there was radiological evidence of pneumoconiosis; small-irregular opacities were less common than category 2. There were positive cases in all departments, but only in workers with over 10 years exposure. The incidence rate of chronic bronchitis was related to the job and the length of exposure, taking into account smoking habits. The clinical classification of chronic bronchitis met the criteria of the E.C.C.S. definition. 23.5% of the exposed group gave positive answers to the questionnaire on chronic bronchitis. The respiratory symptoms were related to the job and the length of exposure. In smokers there was a higher incidence of chronic bronchitis than in non-smokers. Statistical analysis showed that exposure and smoking habits have a potentiating effect on respiratory tract disease in the more severely exposed group. Functional ventilatory changes were classified as obstructive in type and were well related to the symptoms of chronic bronchitis.