Hospital admissions attributable to reduced air pollution due to clean-air policies in China

The Air Pollution Prevention and Control Action Plan (APPCAP) is considered to be the most stringent air pollution control policy in China implemented since 2013. This policy is a milestone in China to mitigate serious air pollution. However, health benefits attributable to reduced fine-particulate air pollution after the implementation of the APPCAP have not been quantitatively estimated on a PM_2.5 constituent-specific and morbidity cause-specific basis. Here we conducted a nationwide case-crossover study based on hospital admission records in 292 Chinese cities during 2013-2017. Compared with 2013, the annual average concentrations of PM_2.5 and black carbon (BC) in 2017 decreased by 28.61% and 20.35%, respectively. As a result, the average relative reductions in annual attributable fractions of nine major cause-specific hospital admissions associated with PM_2.5 and BC were 30.00% and 21.14%, respectively, among which annual attributable fraction for depression showed the largest reduction. Nationally, cities with higher reductions in PM_2.5 and BC were found to have higher absolute reductions in annual hospital admission attributable fractions associated with PM_2.5 and BC, and geographic inequality in health benefits still existed. Our study highlights the substantial wide-ranging health benefits of reduced PM_2.5 and BC levels following the nationwide implementation of the APPCAP in China.