Lung function abnormalities among garri processing workers in Ogbomoso, Nigeria

Local production of garri (cassava crisps) is associated with air pollution and consequently lung function abnormalities among garri processing workers. This study was aimed at describing lung function abnormalities among Nigerians engaged in cassava crisps (garri) processing.

A total of 351 workers and 351 controls were recruited at garri factories in Ogbomoso, Nigeria by multistage random sampling technique. Lung functional abnormalities were defined according to standardised European Respiratory Society/American Thoracic Society guidelines. Data analysis was performed using the IBM SPSS statistics version 22.0.

The mean age of patients was similar to that of controls (41.7 ± 14.9 vs. 41.6 ± 14.7 yearsP = 0.960). Larger proportion (46.2%) of cassava crisps factory workers had abnormal ventilatory function parameters compared to 6.8% in controls (P < 0.001). The mean peak expiratory flow among garri factory workers was significantly lower than that of the controls; 268.25 ± 86.20 versus 349.04 ± 97.21 (L/min) (P < 0.001), likewise the mean forced vital capacity (FVC) (litres) and forced expiratory volume (FEV₁) (litres) of garri factory workers and controls were significantly lower than those of the controls; 2.55 ± 1.07 versus 2.87 ± 0.79 (P < 0.001) and 2.00 ± 0.76 versus 2.41 ± 0.83 (P < 0.001) with FEV₁/FVC ratio of 0.82 ± 0.16 versus 0.87 ± 0.06 (P < 0.001), respectively. The restrictive pattern of ventilatory functional abnormality was predominant among garri factory workers, 92 (26.2%). Sixty-two (17.7%) and 8 (2.3%) of garri factory workers had an obstructive and mixed pattern of ventilatory function abnormalities, respectively.

Garri processing workers had significant ventilatory function impairment. Preventive strategies should be encouraged to reduce occupational hazards associated with garri processing in Nigeria.