Source Identification and risk assessment of BTEX compounds in occupational exposure of Bus Rapid Transit (BRT) drivers in limited traffic zone of Tehran in 2015-2016

Recently, there is an increasing concern about the quality of breath air in cabins of public transportation system. Present study measured the driver’s occupational exposure of BTEX as the most important and toxic group of VOCs in cabins of Tehran bus rapid transit (BRT) system. NIOSH 1501 was used for sampling and analyzing. Samples were extracted by CS2 and analyzed by GC-FID. The main sources of target pollutants were determined and the risk carcinogenic and non- carcinogenic of these compounds were evaluated by USEPA and WHO methods. SPSS Ver.20 was used for Statistical processing of data and Wilcox-test and Kendal were used for comparison and correlation, respectively. The mean inner concentration of Benzene, Toluene, Ethylbenzene, (m+p) - Xylene, o- Xylene and BTEX was measured 8.75, 24.33, 25.90, 43.71, 33.46 and 136.15 µg/m3, respectively. The lifetime cancer risk (LTCR) of Benzene in line 1, 2 and 7 was 7.07×10-5, 4.68×10-5 and 3.08×10-5, respectively. Mean concentration of Benzene was more than Iran environmental protection organization and European :::union::: (EU) recommended levels. LTCR of Benzene was more than recommended levels by USEPA and WHO. The Hazard Quotient (HQ) of all under investigation compounds were less than 1. Therefore, non-carcinogenic risk of them was in acceptable range.