Online consumption and sustained air pollution exposure: Evidence from a quasi-experiment in China

This study examines how air pollution affects household consumption in the digital economy. Using a proprietary dataset constructed from more than 500 million online transactions across 291 Chinese cities from 2017 to 2019, we study how online spending changes when pollution rises. To identify causal effects, we exploit quasi-exogenous variation in air quality generated by China’s winter heating policy and implement a difference-in-differences design comparing northern and southern cities around the heating period. We find that pollution increases online spending on health-related products and necessities and reduces spending on non-essential goods. The response is concentrated in the heating period itself, with little evidence of stockpiling before or delayed adjustment afterward. Item-level evidence shows that the increase in spending operates mainly through higher quantities purchased rather than higher payment per item. Additional evidence from Baidu search activity suggests that the spending response is associated with greater attention to pollution risks and protective products, as well as worse mood.