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Investigation of the efficiency of carbon nanotubes coated with cobalt and molybdenum nanoparticles in the removal of elemental mercury vapors from the air
Full text linkEvaluation of the strength of all ceramic crown with modified core complex with resin and ceramic
Full text linkبررسی آگاهی، نگرش و عملکرد متخصصین درمان ریشه ایران در مواجهه با بیماران قلبی در سال ۱۴۰۰-۱۳۹۹
Full text linkبررسی مقایسه تاثیر مدل اطلاعاتی-انگیزشی-رفتاری و مشاوره روانی آموزشی بر رضایت جنسی و روش پیشگیری از بارداری تحت اجبار همسر در زنان مراجعه کننده به مراکز بهداشتی درمانی شهر کرمان سال ۱۳۹۹-۱۳۹۸
Full text linkبررسی تاثیر پیش درمانی با رسوراترول بر اثر ضدتشنج اسید والپروئیک در تشنج ناشی از پنتیلن تترازول در موش
Full text linkمقایسهی میانگین ابعاد کرونهای استیل زنگ نزن دندانهای مولر اول و دوم شیری مورد استفاده در ایران با متوسط ابعاد این دندانها در کتاب آناتومی و مورفولوژی دندان
Full text linkEvaluation of oxidative stress and DNA damage caused by Paraquat poisoning in animal model
Full text linkInvestigation of pesticides residues (Deltamethrin, Abamectin, Acetamiprid) in crops grown on the farm and in the greenhouse
Full text linkMeasurement of BTEX (benzene, toluene, ethylbenzene and xylene) concentration at gas stations
Full text linkBackground: Fuel stations are one of the major sources of air pollution with volatile organic compounds,
especially the four main petrol compounds benzene, toluene, ethylbenzene, and xylene (BTEX). BTEX
in gasoline enters the air of gas stations due to high evaporation of gasoline. Therefore, determining the
concentration of these compounds in gas stations in crowded and busy cities is one of the important
priorities of environmental health, which is doubly important in terms of its negative effects on health.
Methods: In this descriptive cross-sectional study, a total of 39 samples were collected from 13 gas
stations. Sampling was performed in autumn 2018 in three working shifts (morning, noon, and night).
The method NIOSH-1501 (i.e., using charcoal sorbent tubes and SKC pump with a flow rate of 0.2
L/min) was used for sampling the BTEX compounds. The mean difference and correlation of BTEX
compounds based on meteorological parameters and the number of nozzles in gas stations were assessed
using one-way ANOVA and correlation tests.
Results: The mean and standard deviation of benzene, toluene, ethylbenzene, and xylene concentrations
in the air of fuel stations were 2.784 ± 1.461, 3.495 ± 1.390, 2.091 ± 0.811, and 1.140 ± 0.419 mg/m3,
respectively. The relationship between BTEX compounds and meteorological parameters such as
humidity and exposure time is very important. There is a strong correlation between the concentrations
of BTEX compounds. The highest correlation was observed between benzene and toluene and the
lowest one was observed between benzene and xylene. In this study, no significant relationship was
observed between air temperature and concentration of BTEX compounds, but there was a relationship
between relative humidity and the concentration of BTEX compounds.
Conclusion: The average benzene concentration in the air at the fuel stations was about 5.5 times the
standard limit. Authorities should improve fuel quality and reduce its evaporation through engineering
measures to overcome the issue.
Keywords: BTEX, Gas stations, Ira
