Investigation of the spatioal and temporal trends of Tabriz air pollution during (2006 - 2016) and estimation of attributed death

Abstract

This study was conducted to investigate the long-term temporal trends and spatial variations of ambient PM10, PM2.5, O3, NO2, NO, SO2 and CO concentrations and also to evaluate their health effects in Tabriz city, between 2006 and 2017. Real-time hourly concentrations of PM10, O3, SO2, NO2, NO, PM2.5, and CO measured at nine air quality monitoring stations (AQMSs) were obtained from the Tabriz Department of Environment (TDoE) during 2006-2017 and analyzed. Spatial and temporal variations of pollutants using the Moran’s I index and Mann-Kendall's test and were analyzed. In addition, the health impacts of air pollutants were estimated using the World Health Organization (WHO) AirQ+ software updated in 2017. The results of this study showed that the annual trend of PM10, PM2.5 and SO2 was decreasing while concentrations of NO2, NO and CO was increasing but was almost constant for O3 during the study period. During some of the studied days for PM10, PM2.5 and SO2 levels were exceeded greater than the WHO AQG and National and U.S.EPA standard levels. Moreover, the highest monthly mean concentrations of PM10 in Mehr (80.3 µg/m³), PM2.5 and SO2 in Dey (42.9 and 45.7 µg/m³) and O3 in Khordad (77.8 µg/m³), NO and CO in Azar (53.7 µg/m³ and 4.3 Mg/m³) and NO2 in Bahman (87.3 µg/m³) were observed. Compared between the stations, the Raste Kuche Station was more polluted than the other stations. It was estimated that attributable proportions due to long-term exposure to PM10 were between 7.9% and 28.7% for post neonatal infant mortality and between 20.7% and 61.5% for incidence of chronic bronchitis in adults. the number of death due to long-term exposure to PM2.5 was about 9% for all causes, 32.7% for IHD, 24.8% for stroke, 21.3% for COPD, 21.4% for ALRI and 14.4% for lung cancer. Our study results showed that there were no effective policies and strategies to reduce Tabriz air pollution during the study period; and codification and implementation of effective control policies is necessary to improve ambient air quality of Tabriz. Effective control planning and implementation policies are essential to improve the air quality of the Tabriz environment. So this information provides a key step for city managers, policymakers, and health officials to reduce the health impacts of air pollution.