Inhalation exposure and related health risks of BTEX in ambient air at different microenvironments of a terai zone in north India

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

“…5 and Table 3, the average LTCRs of benzene in the morning and evening were 1.96×10 −4 and 2.49×10 −4 , respectively, which exceed the recommended value by US EPA and WHO. Similar findings have been obtained by Li et al (2014) in the ambient urban atmosphere of Beijing (China) (Li et al, 2014), in the north urban atmosphere of India (Masih et al, 2016), and by a gas station in Bangkok, Thailand (Tunsaringkarn et al, 2012) with mean LTCR values of benzene reported at 1.34×10 −5 , 4.6×10 −6, and 1.75×10 − 4 , respectively. In addition, different results have been obtained by Miri et al (2016) in the ambient air in Tehran, Iran and Hu et al (2010) in the ambient air in Nanjing, China with mean LTCR values of benzene reported at 3.93×10 −7 and 1×10 −7, respectively.…”

“…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.…”

“…The ratio of B to T is generally utilized as an identifier for emission sources of target compounds (Hazrati et al, 2016b; Jiang et al, 2017; Masih et al, 2016; Miri et al, 2016). Table 1 compares BTEX concentrations and it various ratios in the current study versus other regions.…”

“…Small X/B and Ebz/B ratios in our study suggest that the sampled air masses were photochemically aged (e.g., via reactions with hydroxyl radicals) and that benzene has a relatively low reactivity as compared with ethylbenzene and xylenes. Therefore, M&P-xylene, ethylbenzene and o-xylene could be included in photochemical reactions with hydroxyl radicals (Bauri et al, 2016; Jiang et al, 2017; Masih et al, 2016; Muezzinoglu et al, 2001). These results emphasize the findings of previous research, in which the minimum concentration of BTEX species was for ethylbenzene and xylenes (Bauri et al, 2016).…”

“…Ideal regions to study BTEX emissions and impacts include ‘hot spots’, which are typically urban areas where ambient levels significant exceed those of surrounding remote areas (Zhu et al, 2008). Pollution in developing countries has significantly increased in recent years and fresh emissions especially are a major health concern for large populations in these areas (Bauri et al, 2016; Hazrati et al, 2016b; Masih et al, 2016; Rad et al, 2014; Saxena and Ghosh, 2012; Tunsaringkarn et al, 2014). …”