Ventilatory function in Nigerian asbestos factory workers.

Ventilatory function indices; forced vital capacity (FVC), forced expiratory volume in one second (FEV1), the percentage of vital capacity in one second (FEV1%) and peak expiratory flow rate (PEFR) were measured to find the effect of asbestos fiber on lung function in 95 male Nigerian asbestos factory workers (aged 25-55 years). The results were compared with a control group of age and sex-matched Nigerians from the same area that were not exposed to asbestos fiber or any known air pollutant. The results were also compared with expected values calculated from linear regression equations worked out for healthy Nigerians. The mean values of FVC, FEV1 and PEFR were significantly lower in the asbestos factory workers than in the control group (P less than 0.01, 0.05 and 0.001 respectively). FEV1 in asbestos factory workers showed a statistically significant negative correlation with the duration of service (P less than 0.05). The reduced FVC and FEV1 and normal FEV1% in asbestos factory workers is indicative of restrictive lung defect and may be attributed to asbestos fiber exposure. Frequent monitoring of the health of these factory workers and control measures should be stepped up in the factory.