Urban Policy Interventions to Reduce Traffic Emissions and Traffic-Related Air Pollution: A Systematic Evidence Map

Abstract

BACKGROUND AND AIM: Cities are the world’s engines of economic growth, innovation and social development. They are also hot spots for human exposure to air pollution, mainly originating from traffic. As the urban population grows rapidly, a greater number of people risk exposure to traffic-related air pollution (TRAP) and its adverse, costly health effects. In many cities, there is scope for air quality improvement through targeted policy interventions. This systematic evidence map (SEM) examines and characterizes peer-reviewed evidence on urban-level policy interventions to reduce traffic emissions and/or TRAP from on-road mobile sources, thus potentially reducing human exposures and adverse health effects. METHODS: A previously published protocol details the methods utilized in this SEM, including literature search strategy, eligibility criteria, article screening, data extraction and coding, data visualization, synthesis, and database description (Sanchez et al., 2020). RESULTS:We identified and screened 7528 unique articles from database searches and included 378 articles, published between January 1, 2000 to June 1, 2020, in the final SEM. Data was recorded for various policy interventions implemented across the globe. Documented data includes study characteristics, population characteristics, policy intervention category, study area, pollutants studied, if the effect on traffic emissions and/or TRAP was studied and its direction, if human exposures and health effects were studied, and enablers, barriers, and co-benefits. The evidence recorded for each intervention will be hosted in an open-access, queryable database available on the CARTEEH Data Hub (https://carteehdata.org/). Data visualizations will be created in Tableau Public based on the final database, and a demonstration of these will be delivered during the conference presentation. CONCLUSIONS:This is the first peer-reviewed SEM compiling international evidence on urban-level policy interventions to reduce traffic emissions and/or TRAP in the context of human exposure and health effects in cities. The open-access database is a valuable resource for policymakers and researchers. KEYWORDS: air pollution, policy, policy and practice, exposures, health co-benefits, traffic-related