The effect of power plant fuel change on the air pollution (SO2 and NOX ) of surrounding areas: A passive measurement method and health risk assessment

Abstract Background This study aimed to measure the concentrations of sulfur dioxide (SO2) and nitrogen oxides (NOX) and their relationship with the variables of changing seasons and fuel consumption for Qom Combined Cycle Power Plant in three stations around the power plant from December 2014 to May 2015. Methods In this study, passive sampling was employed in three monitoring sites around the power plant, namely, Pardisan, Mahdiyeh, and Sagheh stations and health risks were assessed for non-carcinogenic effects of exposure to SO2 and NOX via the inhalation route. Results Results showed that the maximum mean concentration values of NOX in winter (when power plants used gasoil) and spring (when power plants used gas fuel) were 52.70 ± 21.70/52.70 ± 13.20 and 22.10 ± 7.00 µg/m3, which were related to Mahdiyeh/Pardisan and Pardisan stations, respectively. In addition, the maximum mean concentration values of SO2 in winter and spring were 5.00 ± 0.20 and 3.90 ± 0.70µg/m3, both for the Mahdiyeh station. Results showed moderately significant correlation between NOx and SO2 concentration values when the power plant consumed gasoil (Spearman rho coefficient 0.68, p < 0.05). Furthermore, significant correlation was observed between gaseous concentration values and the change in power plant fuel type (p < 0.05). The SO2 Hazard quotients (HQ) values for all age groups were less than 1.00. But the NOx HQ values for less than 2 years old (Infants) and 2–6 years old (Children) were more than 1.00 and for other groups were less than 1.0. Furthermore, the Hazard index (HI) calculation showed that HI for NOx was 3.65, which were > 1, showing an unacceptable chance to human health. Conclusions In conclusion, the use of gasoil by power plants will remarkably increase the emission of pollutants and consequently the concentration of the pollutants in surrounding areas, thereby increasing the health risk for residents of these regions particularly for children which shows the importance of clean fuel supply and the use of emission control technology in the power plant.