Waste import and air pollution: Evidence from China's waste import ban

In this paper, we investigate the impact on air pollution of China's 2017 policy banning waste imports. We exploit a difference-in-differences strategy combining the time variation and cross-prefecture variation in waste imports before the policy change. We find that prefectures that imported waste in the prepolicy period experienced greater air quality improvements after the policy shock. This effect is stronger in regions with loose environmental regulations and poor waste utilization capacity. Further investigation shows that reductions in both the burning of unrecyclable waste and the level of industrial production are channels through which the waste import ban reduced air pollution.