COVID-19, City Lockdown, and Air Pollution: Evidence from China

Guojun He; Yuhang Pan; Takanao Tanaka

(2020) use seasonal agricultural straw burning as the instrumental variable for PM2.5, and estimate how PM2.5 affects mortality; and Fan et al. (2020) examine how turning on the coalfired winter heating system affects weekly mortality. 8 These studies estimate that a 10 µg/m 3 increase in PM2.5 would lead to a 2.2%~3.25% increase in mortality, which is largely consistent with a recent quasi-experimental study in the U.S. (Deryugina et al., 2020) . 9 8 A few other studies also use quasi-experimental approaches to estimate the impacts of air pollution on mortality in China, including Chen et al. (2013 ), He et al. (2016 , and Ebenstein et al. (2017) . However, these studies are less relevant to our research context because they use data from at least a decade ago and focus on coarse measures of air pollution, such as total suspended particles (TSP), or on PM10. 9 We summarize the related studies in Appendix Table A8 . We see that quasi-experimental studies find larger effects on mortality than associational studies.