Region-oriented simultaneously joint two-pollutant control strategies required to substantially reduce deaths attributed to both PM2.5 and ozone pollution in China

Abstract

China is confronting serious air pollution of fine particulate matter (PM2.5) and ozone, which routinely exceed air quality standards. PM2.5 concentrations decreased by 30-40% while ozone increased by 15-20%, across China during 2015-2019. This could be attributed to targeted clean air policies that have focused more on controlling particulate matter since 2013. The deaths attributable to PM2.5 and ozone exposure over China changed from 1.45 and 0.13 million in 2015 to 1.04 and 0.21 million in 2019, respectively. The changes in mortality, PM2.5 and ozone present spatially heterogeneous patterns across cities and regions. The ozone production regimes (NOx -limited, volatile organic compounds (VOCs)-limited or transition between them), the responses of P(O3) to the change in NOx and VOCs, the reactions of HO2, OH, and RO2, and meteorological conditions, are regionally dependent and spatially heterogeneous. Our results have important implications for developing a smarter, region-oriented, two-pollutant coordinated control policy for VOCs and NOx in China.