Pollutant emission reductions deliver decreased PM2.5-caused mortality across China during 2015-2017

Abstract

Air pollution is a serious environmental issue and leading contributor to disease burden in China. Rapid reductions in fine particulate matter (PM2:5) concentrations and increased ozone concentrations occurred across China during 2015 to 2017. We used measurements of particulate matter with a diameter ≤ 2:5 μm (PM2:5) and ozone (O3) from more than 1000 stations across China along with Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) regional air quality simulations, to explore the drivers and impacts of observed trends. The measured nationwide median PM2:5 trend of 3:4μgm3 yr1 was well simulated by the model (3:5μgm3 yr1).With anthropogenic emissions fixed at 2015 levels, the simulated trend was much weaker (0:6μgm3 yr1), demonstrating that interannual variability in meteorology played a minor role in the observed PM2:5 trend. The model simulated increased ozone concentrations in line with the measurements but underestimated the magnitude of the observed absolute trend by a factor of 2. We combined simulated trends in PM2:5 concentrations with an exposure-response function to estimate that reductions in PM2:5 concentrations over this period have reduced PM2:5-attributable premature mortality across China by 150 000 deaths yr1.