Health Benefit Evaluation for PM2.5 as Well as O3-8h Pollution Control in Chengdu, China from 2016 to 2020

Both particulate matter with aerodynamics of less than 2.5 (PM2.5) and ozone are the two main air pollutants in China, which seriously endanger human health. To estimate the adverse impacts of PM2.5and ozone on human health during the implementation of air pollution prevention and control actions in Chengdu, both the generalized additive model and the nonlinear distribution lag model of epidemiology were adopted to explore the exposure-response relationship coefficients β of daily ozone 8h maximum concentration average (O3-8h), as well as that of PM2.5on disease deaths in Chengdu from 2014 to 2016. On this basis, the environmental risk model and environmental value assessment model were both adopted to evaluate the health effects and health benefits in Chengdu from 2016 to 2020, respectively, with the assumption that PM2.5and O3-8hconcentration were reduced to specified air pollution control limits (35μg·m-3and 70 μg·m-3, respectively). The results showed (1) the annual concentration of PM2.5presented gradually decreasing trends in Chengdu from 2016 to 2020. Specifically, ρ(PM2.5) from 63μg·m-3in 2016 decreased to 40. 92μg·m-3in 2020. The average annual decline rate was approximately 9. 8% . In contrast, the annual concentration of O3-8hfrom 155μg·m-3in 2016 increased to 169 μg·m-3in 2020, and the increasing rate was approximately 2.4%. (2) Both PM2.5and O3-8hhad lag effects on three types of disease deaths. Under the maximum lag effect, the corresponding exposure-response relationship coefficients β of PM2.5were 0.000 360 0, 0. 000 500 1, and 0. 000 923 7 for all-cause, cardiovascular, and respirator}- premature deaths, respectively, whereas the corresponding β of O3-8hwere 0.000 3103,0.000 672 6, and 0.000 700 2, respectively. (3) If ρ (PM2.5) was reduced to the national secondary standard limit (35μg·m-3), the corresponding number of health beneficiaries and economic benefits declined yearly. Specifically, the health beneficiary number of all-cause, cardiovascular, and respiratory disease deaths were reduced from 1 128, 416, and 328 in 2016 to 229, 96, and 54 in 2020, respectively. There were a total number of 3 314 avoidable premature deaths for all-cause diseases during the five years, resulting in a total health economic benefit of 7.66 billion yuan. (4) If we assume that ρ(O3-8h) was reduced to the concentration limit specified by the World Health Organization (70 μg·m-3), the corresponding number of health beneficiaries and economic benefits were increasing yearly. Specifically, the health beneficiaries' numbers of all-cause, cardiovascular, and respiratory disease deaths rose from 1 919, 779, and 606 in 2016 to 2 429, 1 157, and 635 in 2020, respectively. The annual average growth rates of avoidable all-cause and cardiovascular mortality were 6.85% and 10.72%, respectively, which was higher than the annual average rise rate of ρ(O3-8h). There were 10790 total avoidable deaths from all-cause diseases during the five years, resulting in a total health economic benefit of 26. 62 billion yuan. These findings indicate that PM2.5pollution in Chengdu had been well controlled, whereas O3pollution had become more severe and had become another key air pollutant threatening human health. Therefore, the synchronous control of PM2.5and ozone should be implemented in the future. © 2023 Science Press. All rights reserved.