Waste Import and Air Pollution : Evidence from China's Waste Import Ban

In this paper, we investigate the impact of China's policy in 2017 to ban waste imports on air pollution. We exploit the difference-in-differences strategy, which combines the time variation and the cross-prefecture variation in the waste import before the policy change. We find that prefectures importing more waste in the pre-policy period experience more improvement of air quality after the policy shock. This effect is stronger in regions with loose environmental regulations and poor waste utilizing capacity. Further investigation shows that reduced burning of the unrecyclable waste and reduced industrial production are channels through which the waste import ban policy reduces air pollution