Measuring the 1, 3-Butadiene and simulating the method of its releasing by GIS application and evaluating the cancer risk in Tehran municipality's 9th district in 2019- 2020

According to the heavy traffic in Tehran, a high amount of 1, 3-Butadiene (BD) in this city is highly expected. This study has been estimated the lifetime cancer risk (LCR) attributable to BD people exposure in Tehran municipality's 9th district and simulation the way of its releasing. This research is an applied study that has been done in the form of field research. Cancer risk assessment were carried out based on the United States Environmental Protection Agency method. BD concentration measurements were performed at 30 points which specified in the area and daily at three different time in four seasons since autumn of 2019 till summer of 2020. LCR then was calculated for four different groups of residents, employees, first and second classes of the pedestrian. Finally, the way of releasing BD in the 9th district was evaluated by GIS software. The results showed that the highest and lowest BD concentrations were 2819 and 424 ppb, respectively, in autumn and spring and were measured in the north and west side of the 9th district which much higher than inhalation reference concentration, in addition the LCR estimation of population due to exposure with high level of BD are exceeded the USEPA benchmark of 1 × 10-6 in the 4 specified groups. So that the amount of LCR in the residents is 790 times more than the USEPA benchmark. According to the results, the necessity for traffic control by urban management and producing green vehicles to prevent pollutants emission is essential.