Can promoting ethanol gasoline usage improve air quality? Evidence from Tianjin, China

Promoting the use of ethanol gasoline is an important approach for China to achieve sustainable and high-quality development. Based on the daily air quality data of Tianjin, China, from 2013 to 2020, this paper in-vestigates whether the implementation of the ethanol gasoline policy helped improve air quality using regres-sion discontinuity analysis. We find that the implementation of the ethanol gasoline policy had a very limited positive effect on the overall air quality index (AQI) and no obvious effect on the reduction of particulate mat -ter (PM2.5 and PM10). However, the results reveal that the ethanol gasoline policy reduced SO2, NO2, and CO by about 36%, 19%, and 20%, respectively. These findings provide policy insights for other cities in China and other rapidly developing cities in the world to promote the use of ethanol gasoline.