Evaluation of Volatile Organic Compounds at Petrochemical Complexes in Iran

The operation of petroleum refineries and petrochemical plants is associated with the emission of organic compounds into the atmosphere, causing local and regional pollution that is harmful to people’s health.
The present study aimed at determining and evaluating personal exposure to hazardous compounds in ambient air of petrochemical complex in south of Iran.
A total of 716 air samples were collected at 18 complexes of an Iranian petroleum complex. A charcoal desorption tube was used to obtain samples from VOCs, and a gas chromatography equipped to flame ionization detector (GC-FID) was used for analyzing the compounds. A gas chromatography-mass spectrophotometer (GC-MS) was used to determine the quantity of the compounds.
More than 40 VOCs were detected in all samples and high concentrations of benzene were observed in 12 complexes, but the concentrations of non-carcinogen compounds were below the occupational exposure limit. The greatest amount of exposure to the VOCs occurred in the groups of operators, site workers, analyzers, mechanics, samplers, and site men. Other possible carcinogenic compounds such as epichlorohydrin ethylbenzene were above the occupational permissible exposure limits in a few petrochemical complexes. The mean ratios of benzene to toluene (B/T), (benzene to xylenes) B/X, ethylbenzene to toluene (EB/T), and ethyl benzene to xylene (EB/X) were, respectively, 1.2, 1.9, 0.12, and 1.2 during the summer and were less than the same ratios in the winter.
The results of this study revealed that benzene is a major pollutant in workplaces and is distributed throughout petrochemical complexes by wind. Thus, there is an urgent need to control the spread of benzene through air. Photochemical reaction is also an important factor in pollution in different seasons of the year.