Health benefits by attaining the new WHO air quality guideline targets in China: A nationwide analysis

To reduce the high disease burden caused by air pollution, World Health Organization (WHO) issued a new air quality guideline (AQG) on the 22nd September 2021. A timely quantitative assessment of health benefits by meeting these targets is a key measure to advocate and inform national and regional disease control policies. We collected daily major air pollution data in 315 Chinese cities from the 1st January to the 31st December 2019, and the corresponding annual population and mortality rate in the whole population of each city. Then, the mortality benefits were estimated when daily air pollution levels attained WHO's new AQG targets (15 μg/m³ for PM_2.5, 25 μg/m³ for NO₂ and 100 μg/m³ for O₃) in 315 Chinese cities and 31 provinces by using pollutant- and cause-specific concentration-response functions. In total, 134,025 (95%CI: 92,768; 173,029) air pollution-associated non-accidental deaths could be avoided in 315 Chinese cities in 2019 by attaining WHO's new AQG targets, with 43,800 (95%CI: 29,945; 55,616) avoidable deaths from PM_2.5, 58,070 (95%CI: 45,333; 70,714) from NO₂, and 32,155 (95%CI: 17,490; 46,699) from O₃. Cardiovascular diseases and respiratory diseases accounted for 72,698 (95%CI: 46,561; 101,680) and 17,726 (95%CI: 8603; 26,925) avoidable deaths, respectively. Health benefits from reduction in air pollution levels were 99.26 avoided non-accidental deaths per million population at national level, ranging from 12.48 per million in Tibet to 166.26 per million in Hebei. These findings suggest that the compliance with the WHO updated AQG standards would save substantial amount of air pollution-related premature deaths in China. More stringent air pollution control and management measures are urgently warranted to reduce the disease burden from air pollutants in China, particularly for the worsening O₃ pollution.