Document Type : Research article


1 M.Sc. Department of Occupational health, Faculty of Health, Mazandaran University of Medical Science, Sari, Iran.

2 PhD Student, Department of Occupational health, Faculty of Health, Shahid-Beheshti University of Medical Science, Tehran, Iran.

3 PhD Student, Department of Occupational health, Health Sciences Research Center, Faculty of Health, Student Research Committee, Mazandaran ‎University of Medical Sciences, Sari, Iran.

4 M.Sc. Department of Environmental health, Faculty of Health, Shahid-Beheshti University of Medical Science, Tehran, Iran.


Background and Aims: ٌWith increasing the number of motor vehicles that causes increasing the fuel production and sale, the ambient air quality has been worse. BTEX is one group of the important pollutants that release from gasoline and its burning. The aim of this study is evaluation of BTEX level in refueling station ambient air.
Methods: In this cross-sectional study, the air samples were taken from 24 workers’ breathing zones in 12 gasoline and CNG refueling stations. Samples were analyzed according to NIOSH1501 method and using GC-FID technique.  SPSS-v.16 is used to analyze data with t-test and Linear Regression (p<0.05).
 Result: The mean concentration of benzene, toluene, ethyl-benzene and xylene in gasoline stations was 1787±327, 914±141, 973.4±183 µg/m3 and 476.1±123 respectively, and about CNG stations, there were 1142/9±863, 507.6±458, 694.9±514 and 296±245.6 µg/m3, in that order. The CNG station’s workers, who exposed to benzene, have cancer risk about 15.8×10-6 and the highest HQ index was related to xylene (i.e. 8.656). The cancer risk of gasoline station workers and HQ index were 21.6×10-6 and 16.19 respectively.
Conclusion: Gasoline stations had the highest concentration of benzene that exceeded the OEL-TWA. Cancer and non-cancer risk is in high levels that require decisions to control the condition. Improvement of fuel quality, implementation of vapor recovery systems, smarting the refuel instruments, utilization of plants for purification of BTEX and using of personal protective equipment are our recommendation for improvement of condition.


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