Abstract
Regional air pollution is one of the most important problems in large cities in developed countries. Road traffic suppression is thought to be one effective tool, however, the effect has not been fully understood. In this study, we examined the influence that the reduction of road traffic volume has on regional air quality by studying air quality during traffic restriction for the 2015 Tokyo Marathon race. The data from two air monitoring stations were analyzed: one located nearby the marathon course (road-side station), the other located in a residential area approximately 650m northwest from the road-side station (residential station). At the time of traffic regulation, it was found that NOx concentration at the road-side station was lower than at the residential station. One the other hand, PM2.5 concentrations did not differ between the two stations. In future research, it will be necessary to study how to evaluate the impact of long-term traffic regulations not only in road-side areas but also in residential areas.
https://ror.org/046ra6g36 
