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

Abstract

This study reports a spatiotemporal characterization of toluene, benzene, ethylbenzene, and xylenes concentrations (BTEX) in an urban hot spot in Iran, specifically at an bus terminal region in Shiraz. Sampling was carried out according to NIOSH Compendium Method 1501. The inverse distance weighting (IDW) method was applied for spatial mapping. The Monte Carlo simulation technique was applied to evaluate carcinogenic and non-carcinogenic risk owing to BTEX exposure. The highest average BTEX concentrations were observed for benzene in the morning (at 7:00–9:00A.M. local time) (26.15±17.65μg/m3) and evening (at 6:00–8:00P.M. local time) (34.44±15.63μg/m3). The benzene to toluene ratios in the morning and evening were 2.02 and 3.07, respectively. The main sources of BTEX were gas stations and a municipal solid waste transfer station. The inhalation lifetime cancer risk (LTCR) for benzene in the morning and evening were 1.96×10−4 and 2.49×10−4, respectively, which exceeds the recommended value by US EPA and WHO. The hazard quotient (HQ) of all these pollutants was less than 1. The results of this work have implications for public health near ‘hot spots’ such as IKBT where large populations are exposed to carcinogenic emissions.

Concentration and type of bioaerosols before and after conventional disinfection and sterilization procedures inside hospital operating rooms

“…Shiraz is in a semiarid area and the capital of Fars province in southwestern Iran (29 °36′N, 52 °32′ E) with an average elevation of 1500 m above sea level (Dehghani et al, 2018; Delikhoon et al, 2018; Neghab et al, 2017). It is located near Iraq, Saudi Arabia, and Kuwait and has a total population of 1.3 million (Fig.…”

Characteristics and health effects of formaldehyde and acetaldehyde in an urban area in Iran

“…1). It has a population of ~1.8 million according to the recent census report in 2017, that describes it as the fifth most populated city in Iran (Dehghani et al, 2018; Statistical Centre of Iran (SCI), 2016). Shiraz covers 240 km 2 and includes eleven urban terrains with mean population density of nearly 6890 residents per km 2 (Statistical Centre of Iran (SCI), 2016).…”

“…The city is characterized as having a semi-arid climate. This city was categorized as one of the main polluted cities in Iran (Arfaeinia et al, 2017; Dehghani et al, 2018; Fathabadi and Hajizadeh, 2016). The air sampling locations, shown in Fig.…”

“…Afterward, the raster calculation function was used to overlay each layer and create mean maps of FA and AA. The IDW technique is defined as follows (Dehghani et al, 2018): $$\lambda i=Di-\alpha /{\sum }_{i=1}^{n}Di-\alpha$$ where D i , λ i , and α are the distance between station i and an unknown point, the weight of the i sample station, and the weighting power, respectively. Higher weights were assigned to values closer to the interpolated point, following the guidance of past work (Dehghani et al, 2018; Shepard, 1968).…”

“…The number of stations applied in the interpolation is represented by n , which is 16 in this study. Past works have used the IDW method for spatial topography of pollutants such as BTEX compounds in Shiraz, Iran (Dehghani et al, 2018), SO 2 and NO 2 in Mumbai (India) (Kumar et al, 2016), particulate matter in California and Pennsylvania (USA) (Li et al, 2016), and Beijing (China) (Li et al, 2014), and atmospheric wet-deposition in Oregon, Nevada, and Washington (USA) (Latysh and Wetherbee, 2012). …”