The role of oxidative stress in pulmonary function in bakers exposed to flour dust.

Objective. This study aimed to determine the effect of exposure to flour dust on pulmonary function and the role of oxidative stress. Methods. This case-control study was conducted on 163 bakery workers (exposed group) and 177 administrative workers (unexposed group). Pulmonary function and flour dust exposure were measured by spirometry and NIOSH 0500 and 0600 methods. Oxidative stress indices including malondialdehyde (MDA), nitric oxide (NO) and total antioxidant capacity (TAC) were measured in serum samples. Results. The mean respirable and total dust exposure of bakery workers were 2.5 ± 1.72 and 6.53 ± 3.26 mg/m3. The forced vital capacity (FVC) and forced expiratory volume in the first 1 s (FEV1) were significantly lower in the exposed group than in the unexposed group. The levels of MDA and NO were higher in smokers than in non-smokers in the exposed group. The most important variables that predicted FVC and FEV1 were MDA, NO and TAC. With increased exposure to respirable dust, the levels of MDA (β = 3.39, p < 0.001) and NO (β = 16.48, p < 0.001) increased and total antioxidant levels decreased (β = -0.37, p < 0.001). Conclusions. Exposure to flour dust may impair pulmonary function by increasing oxidative stress and weakening antioxidant defense.