National and Sub-national Exposure to Ambient Particulate Matter and its Attributable Burden of Disease in Iran from 1990 to 2016

Abstract

TPS 642: Environmental justice and impacts, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: This work was conducted as a part of the National and Sub-national Burden of Diseases, Injuries, and Risk Factors (NASBOD) Study in Iran. We aimed (1) to estimate national and sub-national long-term exposure of Iranian population to ambient particulate matter (PM) < 2.5 μm (PM2.5) from 1990 to 2016, and (2) to estimate the national and provincial burden of disease (BoD) attributable to PM2.5 in Iran. Methods: We used all available ground measurements of PM < 10 μm (PM10) (used to estimate PM2.5 for some station-years) and PM2.5 from 91 monitoring stations. We estimated the annual mean exposure to PM2.5 for all Iranian population from 1990 to 2016 through a multi-stage modeling process. The BoD, in terms of mortality and years of life lost (YLL) attributable to PM2.5 exposure, was quantified according to the methods developed by the Global Burden of Disease Study. Results: The national annual average PM10 concentration was about 121 μg/m3 in 1990 and 62 μg/m3 in 2016. Both of the PM10 and PM2.5 concentrations exceeded the World Health Organization (WHO) guideline value in all studied years. We estimated that only in 2016, about 41,000 deaths and approximately 3,000,000 YLL could be attributable to the long-term exposure to PM2.5 in Iran. Among the studied causes of death and YLL, ischemic heart disease was the leading, followed by stroke, lower respiratory infection, chronic obstructive pulmonary disease, and lung cancer. In 2016, about 43% of all PM related mortality in Iran was, respectively, in the following provinces: Tehran (12.6%), Isfahan (9.3%), Khorasan Razavi (8.0%), Fars (6.5%), and Khozestan (6.4%). Conclusions: In summary, we found that the majority of Iranians were exposed to the levels of ambient particulate matter exceeding the WHO guidelines, and that the ambient particulate matter imposed substantial burden of disease in Iran in this period.