Contributions Of Major Air Pollution Sources To Fine Particles And Its Diease Burden

One of the major issues that China is confronting is to reduce the ambient PM2.5 level and its health risks.To address this issue,one of the prerequisites is to identify and understand the contributions of major air pollution sources to ambient PM2.5 and its disease burden.This study aims to assess the contributions of coal combustion and other major air pollution sources to ambient PM2.5 and its disease burden,as well as the variation trends in different emission control scenarios in the future.The results can provide reference and foundation for the formation of scientific and reasonable energy and environmental policies to effectively reduce the ambient PM2.5 concentration and its health risks.First this study conducted sensitivity analysis for coal combustion and other major emission sectors using the atmospheric chemistry transport model GEOS-Chem and emission inventories for 2013 and different scenarios in 2030,in order to identify the temporal and spatial distribution of the contributions of major emission sectors and their future variation.Based on the simulation results,this study took the advantage of non-linear risk functions to assess the contributions of major air pollution sources to disease burden attributable to ambient PM2.5.This study found that coal combustion is the dominant contributor for ambient PM2.5 in China in 2013.Industrial coal burning is the largest contributor among the sub-sectors of coal combustion,while transportation and domestic biofuel combustion are two largest sources in non-coal emission sectors.By further analysis of the future variation trend of ambient PM2.5 in the year 2030,this study indicates that in the scenario with the most stringent control policies,the PM2.5 level in most parts of China can decrease to below 35 ?g/m3,which can meet the second concentration limit in the National Ambient Air Quality Standards.However,along with the application of more stringent control measures,the fractional contribution of coal combustion keeps increasing due to the larger reduction of emissions from non-coal sources.Coal remains as the single largest contributor to ambient PM2.5 in the future.Through analyzing the disease burden attributable to PM2.5 and its major sources,this study found that coal combustion led to 366,000 premature deaths in China in 2013,which was the largest source to disease burden due to ambient PM2.5.In future scenarios,the disease burden attributable to PM2.5 keep increasing even in the most strictly controlled scenario,due to the aging of population and increasing prevalence of relative diseases.In addition,the fractional contribution of coal combustion to disease burden increases compared to that in the base year,which still remains as the largest source in the future.For this reason,this study concludes that there is an urgent need for even more aggressive strategies to reduce emissions from coal combustion as well as other major emission sectors,in order to further reduce the PM2.5 level to stabilize and lower the attributable burden of disease.