Benzene, toluene, ethylbenzene and xylene concentrations in atmospheric ambient air of gasoline and CNG refueling stations

Abstract

This study aimed to assess workers' exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) compounds in refueling stations of Ardabil city (Iran). Twenty-four refueling stations including 15 petrol and 9 compressed natural gas (CNG) stations from different regions were selected and monitored for ambient BTEX concentrations. Air samples were taken based on NIOSH Manual of Analytical Method no 1501. Target compounds were extracted using CS 2 and analyzed by GC equipped with FID. Average concentrations of benzene, toluene, ethylbenzene, and xylene were obtained 2.01, 1.80, 2.72, and 1.65 mg/m 3 , respectively. Benzene concentrations exceeded the occupational exposure limit set by the Iran Ministry of Health and Medical Education. Its concentrations were significantly higher in commercial areas (2.72 mg/m 3 ) compared to suburban areas (1.89 mg/m 3 ). BTEX concentrations in gasoline stations were slightly, but not significantly, higher than those in CNG stations. Long-term exposure cancer risk of 1884×10 −6 ±390× 10 −6 and hazard index of 22.83±3.66 were estimated for benzene and BTEX compounds, respectively. The results declare the necessity for controlling BTEX emission (mainly benzene) and monitoring employee's exposure in refueling stations.

Characteristics and health effects of BTEX in a hot spot for urban pollution

“…A factor affecting the diurnal profile of benzene is time-dependent emissions in the vicinity of either gas stations (Kountouriotis et al, 2014; Rattanajongjitrakorn and Prueksasit, 2014) or heavily congested roadways (Correa et al, 2012; Kourtidis et al, 2002; Lin et al, 2011). In addition, the results of this study reveal that the average concentration of BTEX was more than other studies, specifically those conducted in the Tri-City area (Gdansk, Gdynia, Sopot), Poland (Marć et al, 2014), Ardabil, Iran (Hazrati et al, 2016b), and Gorakhpur, India (Masih et al, 2016). This can most likely be explained by the combination of heavy traffic, fuel quality standards, old cars, and vicinity to five gas stations in the sampling region of IKBT.…”

“…These findings are opposite of previous studies since benzene was the most abundant as compared to other components of BTEX in ambient air (Cerón-Bretón et al, 2015; Mohamed et al, 2002; Moolla et al, 2015; Mosaddegh Mehrjerdi et al, 2014; Srivastava et al, 2006). The mean values of benzene observed by Moolla et al (2015) (South Africa), Hazrati et al (2016a, 2016b) (Ardabil, Iran), Mosaddegh Mehrjerdi et al (2014) (Yazd, Iran), Mohamed et al (2002) (United States), Srivastava et al (2006) (Mumbai, India), and Cerón-Bretón et al (2015) (Monterrey, Mexico) were, 313.16, 1690, 1932, 18.94, 539.95, and 55.24μg/m 3 , respectively (Cerón-Bretón et al, 2015; Hazrati et al, 2016b; Mohamed et al, 2002; Moolla et al, 2015; Mosaddegh Mehrjerdi et al, 2014; Srivastava et al, 2006). A factor affecting the diurnal profile of benzene is time-dependent emissions in the vicinity of either gas stations (Kountouriotis et al, 2014; Rattanajongjitrakorn and Prueksasit, 2014) or heavily congested roadways (Correa et al, 2012; Kourtidis et al, 2002; Lin et al, 2011).…”

“…This can most likely be explained by the combination of heavy traffic, fuel quality standards, old cars, and vicinity to five gas stations in the sampling region of IKBT. In addition, previous studies reported that different refineries in Iran generate petrol with different qualities in terms of aromatic compounds (Hazrati et al, 2016b). Benzene included in gasoline varies from 1% to 5%, depending on the countries’ legislation, fuel quality and season (Karakitsios et al, 2007).…”

Assessment of BTEX Concentrations in Air Ambient of Gas Stations Using Passive Sampling and the Health Risks for Workers

“…The toluene, ethylbenzene and xylenes concentrations found in the air of the gas stations in this study did not exceed the limits stipulated by NIOSH and NR-15 (Table 2) Comparing the BTEX concentration levels obtained in this study with other cities in Brazil and the world (Figure 3), the values found these compounds were generally higher those obtained in Rio de Janeiro/Brazil [18], but much smaller those obtained in Bangkok/Thailand [15], Ardabil/Iran [20] and Murcia/Spain [35]. These variations can be attributed to differences in the composition of the fuels used in other countries, and the influence of seasonal and/or weather local factors.…”

Determination of benzene, toluene, ethylbenzene and xylene in field and laboratory by means of cold fiber SPME equipped with thermoelectric cooler and GC/FID method

“…BTEX (benzene, toluene, ethylbenzene, and xylene) are common hazardous volatile organic compounds (VOCs) and toxic air pollutants emitted into the atmosphere from natural and artifi cial sources 1 . These compounds are widely used in industries, such as paint, printing, synthetic rubber and resin, detergent, ink and pesticides.…”