Description of BTEX concentrations with wind roses in Tehran city: the study of monitoring, GIS-zoning maps and risk assessment

Abstract

In the present study, the emission of BTEX compounds has been investigated in a one-year period (2016–2017) in Tehran city. According to, 26 sampling stations were selected in different parts of the city and had been sampled in four seasons of year to determine the concentration of BTEX as well as other meteorological parameters such as temperature, humidity and wind speed. Spatial distribution analysis of BTEX was introduced by using the Inverse Distance Weighting (IDW) method in Arc GIS 10.3. Also, to determine the carcinogenic and non-carcinogenic risk of target compounds, Monte Carlo simulation was used. The results showed that the annual mean of benzene, toluene, ethylbenzene, m-xylene and o-xylene were 30.08 ± 21.97, 54.17 ± 40.29, 25.81 ± 15.21, 27.83 ± 19.1 and 23.16 ± 12.28 μg/m³, respectively. According to the result, the maximum and minimum concentrations of BTEX were in the center and north of the city, respectively. Temporally, the maximum value of BTEX was 232.61 ± 123.93 µg/m³ in the autumn and the minimum value was 57.88 ± 24.93 µg/m³ in the spring. The result obtains from the inhalation lifetime cancer risk (LTCR) indicative the carcinogenic potential of benzene. Noncarcinogenic risk index, namely the hazard quotient (HQ) for all BTEX compound except benzene concentration in the autumn (1.55), were lower than 1 degree so they were not harmful to human health.

Graphical Abstract

Keywords:

• Air pollution
• BTEX
• IDW
• LTCR
• Tehran

Acknowledgments

This article is the result of a research project entitled "Study of BTEX pollutant concentrations and modeling its emission status using advanced statistical models in the air of Tehran" approved by the Medical Unit of Tehran Islamic Azad University No. 30602 in 2015, which with the financial support of Azad University Islamic Tehran has been done. The authors appreciate the cooperation of this university.

Disclosure statement

The authors declare that they have no conflict of interest