Fine-particulate air pollution and behaviorally inclusive mortality impacts of China’s winter heating policy, 2013–2018

China’s spatially discontinuous winter heating policy has been used to examine how sustained exposure to air pollution impacts health. This influential literature exploits quasi-experimental cross-sectional variation in atmospheric emissions in a geographically vast and populous nation. Our study introduces an alternative external definition of the winter heating boundary and takes advantage of an unprecedented expansion of pollution and mortality surveillance, covering at least 10 times more sites and finer-grained pollution particle sizes that are more relevant to health standards today. We estimate spatial discontinuities in pollution and mortality that shrink over time, consistent with tighter emissions regulations, higher quality medical care, and increased air quality disclosure to – and defensive behavior by – the public. We find that in 2013–2015 a 10-μg/m3 increase in PM2.5 raised behaviorally inclusive mortality for cardiovascular and respiratory causes by 11% (95% confidence interval = 2–20%) and lung cancer mortality by 20% (95% CI = 4–37%).