Respiratory problems caused by occupational exposure to flour dust among flour mill workers in Razavi and South Khorasan provinces

Flour dust is one of the allergens in the workplaces and its occupational exposure can cause respiratory impairments. The purpose of this study was to investigate the respiratory effects of exposure to flour dust in flour mill workers. This cross-sectional study was carried out at 6 flour producing factories in Razavi and South Khorasan provinces، Iran. Study subjects included 180 males (90 male workers with current exposure to flour dust and 90 male non-exposed employees). Determination of dust concentration was carried out with personal dust sampler at all production units of studied industries. Respiratory symptoms were investigated with American Thoracic Society questionnaire (Persian version). Lung function tests were done by a calibrated spirometer. The data were analyzed using SPSS (version 16). Mean of age and work experience of exposed group was 36. 8±9. 03 and 12. 0±5. 6 years، respectively. This result، for non-exposed group was 37. 3±8. 1 and 12. 58±5. 5 years، respectively. Atmospheric concentrations of respirable and inhalable dust were 13. 3±2. 38 and 38. 77±3. 6 mg/m3، respectively. Results indicated that prevalence of respiratory symptoms in exposed subjects was significantly higher than non-exposed workers. Likewise، pulmonary function parameters were significantly lower in exposed than reference group (p<0. 05). The findings of this study showed that occupational exposure to flour dust and age could be important factors predicting the prevalence of respiratory symptoms and functional impairment of the lungs