Lung function and respiratory symptoms among workers in an automobile manufacturing factories, Iran

Introduction: Exposure to volatile organic compound (VOCs), dust, and silica can effect on the airways, induced respiratory symptoms, as well as effecting on lung functions. The purpose of this study, was to estimate the prevalence of respiratory symptoms and respiratory disorders among workers exposed to pollutants in the automobile manufacturing factories in Tehran, Iran. Methods: This study was a case-control research performed in 2016. The subjects include 40 workersexposed to different level of dust, BTEX, and silica. 40 unexposed individuals were considered as control group. Methods 1501 and 7602 presented by the National Institute of occupational safety and Health(NIOSH) were used for the sampling and analysis of compounds in the air. In this study, Gas Chromatography- Flame Ionization Detector (GC-FID) was used for analysis of compounds of interest. 6 silicasamples were collected during the campaign. Silica analyses were performed by using visible absorption spectrophotometry system. Lung functions were evaluated for each participant using spirometry system.Results: The average amount of total dust and free silica measured in factory were 7.3±1.04 mg.m-3 and 0.017±0.02 mg.m-3 respectively. Average benzene, toluene, ethyl-benzene and xylene exposurelevels in exposed subject’s median were 0.775±0.12, 1.2±2.08, 45.8±8.5, and 42.5±23.9 ppm respectively. Statistical tests showed significant difference between pulmonary function tests (except PEF) ofexposed and non-exposed individuals before and after employment. Workers exposed to pollutants presented lower levels of FVC, VC, and PEF than the control group except FEV1/FVC%, FEV1, FEF2575and FEV1/VC%. Conclusion: This research demonstrated decline in lung volumes and respiratory symptoms, significantdifference associated with the exposure to dust or gas, duration of exposure, and smoking habit. Therefore, based on the results obtained during this study, lung function tests should be performed before and after the employment to identify sensitive workers candidates.

کلیدواژه ها:

Lung function ، respiratory symptoms ، dust ، silica ، compound BTEX