The article discusses how new tools and data are being used to reduce air pollution from traffic in cities. Scientists are using advanced models to map air pollution levels near roads and develop strategies to improve air quality. Personal monitoring devices and apps are helping people track their exposure and find ways to reduce it. These tools have been successful in identifying ways to lower air pollution, but more research is needed on how they affect people's behavior. In Canada, interventions like clean routes and urban design changes have been implemented to reduce traffic-related air pollution. A study also shows that providing air pollution information can influence individual behavior.