Effect of COVID-19 on transportation air pollution by moderation and mediation analysis in Queens, New York.

The outbreak of the COVID-19 virus in 2020 has left many changes in the quality of life and environment, including air quality in different parts of the world. As a result of lockdown conditions, the level of air pollution has been changed considerably due to topographic, geographical, and cultural conditions as well as traffic restrictions. Thus, this study aimed to investigate the effect COVID-19 outbreak on improving air quality as a result of changes in traffic volume and traffic patterns in Queens, New York, using the moderation and mediation analysis model structure.