Accounting for the Health Benefits of Air Pollution Regulations in China, 2008–2020
Patrick L. Kinney1, Beizhan Yan2, Xiaoming Shi3, Maigong Zhou3, Shuxiao Wang4, Lucas Henneman5, Jia Xing4, Phil Hopke6, Tiantian Li3, Peng Yin3, Howard Chang7, Corwin Zigler8, Haidong Kan9
1Boston University School of Public Health, MA, USA; 2Columbia Lamont Doherty Earth Observatory, Palisades, NY, USA; 3China Centers for Disease Control, Beijing, China; 4Tsinghua University School of the Environment, Beijing, China; 5Harvard T.H. Chan School of Public Health, Boston, MA, USA; 6University of Rochester, NY, USA; 7Emory University, Atlanta, GA, USA; 8University of Texas, Austin, TX, USA; 9Fudan University, Shanghai, China
Background: China launched ambitious air pollution regulations in 2013 that have resulted in substantial improvements in air quality. From 2013 to 2017, PM2.5 levels declined up to 40% in Beijing and other parts of eastern and northern China. Not all regions in China experienced such rapid decreases, with some regions experiencing smaller or even no decrease in PM2.5 (e.g., Sichuan Province). In contrast to the general decline in PM2.5, ozone concentrations increased in some regions since 2013. The large but heterogeneous changes in air pollution present a unique opportunity for accountability research.
Methods: This project will quantify the causal pathway linking regulations, emissions, ambient air pollution, and mortality in response to regulations implemented starting in 2013 in China. First, we will use the community multiscale air quality (CMAQ) model to simulation ambient PM2.5 and ozone throughout China. CMAQ will be run using observed emissions as well as counterfactual emission scenarios that eliminate source-specific emission control policies. We will perform diagnostic evaluations of CMAQ model outputs using air pollution observations. Also, we will evaluate and compare PM2.5 source contributions and their changes estimated by the CMAQ Integrated Source Apportionment Method (ISAM) and observation-based positive matrix factorization (PMF) approaches. In parallel, we will analyze and compare speciated PM2.5 and gaseous co-pollutant measurements from 3 Chinese cities (Beijing, Zhengzhou, and Nanjing) to quantify changing source contributions over time. Next, we will analyze the extent to which regulatory policies, emissions, and/or air quality were associated with reduced mortality. Mortality data will be analyzed from two large nationwide cohorts that have data spanning the periods before and after the implementation of regulations. We will analyze the impacts of regulations on mortality using both standard epidemiologic models as well as novel causal models linking regulations directly to health outcomes.
Results: This will be the first empirical investigation of the mortality benefits of China’s large-scale ambient air pollution control programs. This is made possible by a unique collaboration among an international team of investigators.
Conclusions: Given the scope of air pollution regulations implemented in recent years in China, and the rich exposure and health outcome data now available, this project will provide a unique opportunity to evaluate health accountability associated with large-scale air pollution policies.