The effect of respiratory exposure to benzene, toluene, xylene and ethyl benzene on the spirometric indices among the petroleum products loading workers

Abstract Background and Aim: Benzene, toluene, xylene and ethyl benzene (BTEX) are the most important aromatic compounds in petroleum products. BTEX compounds due to their high vapor pressure, easily change to gas form and mixed with ambient air. Petroleum products loading workers are exposed to these compounds by the inhalation of BTEX compounds. The aim of this study was to evaluate the effects of respiratory BTEX exposure on lung function tests. Method: A cross sectional study in summer of 2015 on petroleum products loading workers was performed to determine workers' exposure to benzene, toluene, xylene and ethyl benzene. Eighteen individual samples of air in the breathing zone using active approach by use of activated charcoal were taken. To determine and evaluate of lung function, spirometric tests was performed according to OSHA protocols. Results: The results of analysis of samples showed that the average exposure to benzene was above the occupational exposure limit and the average exposure to ethyl benzene, toluene and xylene were below the occupational exposure limit. Lung functions indices including FVC, FEV1, FEV1 / FVC and FEF25-75 were reduced. Conclusion: The results showed that exposure to BTEX compounds could affect lung function indices, and reduced them.