A Zero-Waste City, a healthy community: impacts of Zero-Waste City policy on urban residents’ health

This paper treats the first group of Zero-Waste City pilots launched in 2019 as a natural policy experiment. Drawing on a panel of 252 prefecture-level cities over 2012 to 2023, it applies a double machine learning model to identify the causal effect of comprehensive solid-waste governance on urban residents’ health. The results indicate that Zero-Waste City construction brings a significant gain in the health of residents in pilot cities. Channel analysis yields evidence consistent with three proposed pathways: the factor allocation optimization effect, the green innovation driving effect, and the environmental awareness awakening effect. The heterogeneity evidence shows that the improvement is concentrated in central and western cities, in small and medium-sized cities and in non-resource-based cities, whereas the coefficients for eastern, large, and resource-based cities do not reach statistical significance. Health co-benefits should therefore be built into the performance evaluation of Zero-Waste City construction, pilot expansion should proceed city by city rather than uniformly, and policy design should be strengthened along the channels of factor allocation, green innovation and public participation.