Abstract

This study was conducted to establish the effects of flour dust on the lung functions and cardiovascular variables of local flour mill workers in Ijebu Ode Local Government Area of Ogun State, Nigeria. This study involved 35 local flour mill workers and matched controls. The subjects were matched for age, height, weight and socioeconomic status. The pulmonary function tests were done with a portable spirometer. The heart rate and blood pressure of subjects and controls were measured using a digital blood pressure monitor whereas the peripheral oxygen saturation was measured using a pulse oximeter. Independent T-test was used to test the differences in cardiopulmonary variables between the exposed flour mill workers and their matched controls. Regression analysis was used to investigate the effect of duration of exposure to flour dust on lung volumes. Significant reduction in the overall mean values of Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 second (FEV1 ), and Peak Expiratory Flow Rate (PEFR) was observed in the local flour mill workers relative to their matched controls; mean FVC was decreased in the exposed group (1.28±0.13L) when compared with control group (1.90±0.09L) (p<0.001), mean FEV1 was significantly decreased when exposed group (0.99 ± 0.11L) was compared with the control group (1.553 ± 0.0636L) (p<0.0001), likewise the mean PEFR was significantly decreased when exposed group (2.09 ± 0.25L/min) was compared with the control group (3.88 ± 0.23L/min) (p<0.001). Heart rate was significantly increased when exposed group (86.71 ± 1.92) was compared with the control group (77.6 ± 1.48) (p<0.001); the systolic blood pressure was insignificantly increased when exposed group (138.7 ± 5.69) was compared with the control group (131.5 ± 2.642) (p<0.208), the Diastolic Blood Pressure was however significantly increased when exposed group (86.94 ± 2.77) was compared with the control group (79.86 ± 1.79) (p<0.021). Significant negative correlation for the r values were found when FVC, FEV1 and PEFR were regressed on duration (in years) of exposure to flour dust. The FEV1 /FVC ratio of the exposed flour mill workers was on average of 80.5%. Significant reduction in FVC, FEV1 , PEFR and yet a normal FEV1 /FVC ratio is indicative of restrictive pattern of pulmonary disorder.