The effects of road pricing on transportation and health equity: a scoping review

Road pricing is increasingly considered as an option to support transportation infrastructure costs, manage demand, and reduce emissions. However, the extent to which implementation of such approaches may impact transportation and health equity is unclear. In this scoping review, we examine the differential transportation and health effects of road pricing policies across population groups and geographic region. We conducted a systematic database search of Transport Research International Documentation, GEOBASE, Scopus, and Ovid Medline, supplemented by bibliographic review and internet searches. Fifteen studies were included in the review. The studies evaluated area and cordon road pricing systems in Singapore, London, Stockholm, Milan, and Gothenburg, and had a median follow-up period of 12 months. Outcomes evaluated include car commuting, mode shift to public transit, accessibility to destinations, affordability, welfare, social interactions, air pollution, traffic injuries and deaths, acute asthma attacks, and life expectancy. While more studies across diverse urban contexts and policy settings will be needed to strengthen the evidence base, the existing evidence suggests road pricing has mostly net positive effects related to a reduction in car trips, air pollution, asthma attacks, and road traffic collisions, and increases in life expectancy. Frequency and ease of social interactions were found to be negatively impacted, with fewer visits to family and friends. The population groups that generally fared better across transportation and health outcomes were those with higher incomes, men, and people between the ages of 35–55. Across space, there are benefits for both the areas inside and outside the cordon boundary, but to a greater degree for the area inside. Overall, the evidence base is limited by a narrow set of health-related outcomes and a lack of longer-term studies. We did not come across any studies assessing distributional effects of noise pollution, mode shifts to walking or cycling, or other morbidities in the general population that are not listed above. In addition, there are few evaluations that include non-work trips, therefore potentially missing effects for unemployed populations or women who are more likely to make non-work trips. We find that the limited body of evidence on area and cordon pricing policies suggests these policies are beneficial for a number of transportation and health outcomes, particularly for populations inside the cordon area, but that there may be some degree of inequities in the distribution of the benefits and burdens.