[Monitoring of respiratory symptoms and pulmonary ventilatory function in sisal processing workers]

The prevalence of acute and chronic respiratory symptoms and ventilatory capacity was studied in 50 textile workers exposed to sisal dust. A follow-up study was performed 19 years later and included 20 workers out of the 50. The first study showed a considerably higher prevalence of all chronic respiratory symptoms in the exposed than in control workers although the difference was statistically significant only for chest tightness (P < 0.01). Comparison of the prevalence in the first and the follow-up study in 20 textile workers revealed a statistically significant increase in the rate of chronic cough, dyspnea, chest tightness and nasal catarrh. During the follow-up study the prevalence of almost all chronic respiratory symptoms was significantly higher in exposed than in control workers. Results of ventilatory capacity in 50 sisal workers showed acute reductions of FVC and FEV1 during work shift on Monday and the following Thursday. Comparison of the measured and predicted normal values demonstrated lower values in the follow-up study in comparison to those in the first study. The mean annual fall of ventilatory capacity tests was 0.027 L for FVC and 0.036 L for FEV1. Data suggest that long-term exposure to sisal dust may cause the development of chronic respiratory symptoms and lung function impairment in sensitive subjects.