The health impacts of urban transport: Linkages, tools and research needs

Transport is an essential component of the progress and growth of cities and urban areas but has a large negative and inequitable impact on human health. Current knowledge on the health impacts associated with urban transport shows that traffic is causing premature mortality and a large burden of morbidity through nine key pathways: (1) motor vehicle crashes, (2) human physical inactivity, (3) climate change, (4) social exclusion, (5) community severance, and traffic-related environmental exposures including (6) air pollution, (7) noise, (8) green space reduction, and (9) local temperature rises. These exposures and their health effects are not proportionally distributed, notably varying by income and race, whereby lower income and ethnic minority populations are disproportionately negatively affected. Further, these groups exhibit a variety of other factors that make them more vulnerable to adverse environmental exposures including poor diet, suboptimal health care, stress, and violence exposure. Other important vulnerable groups include children and the elderly. In this chapter, we present a conceptual model linking urban and transport planning, environment, and health. We synthesize the key traffic-related exposures and their health effects to frame the issues related to health impact assessment. We review equity issues and the need to incorporate them in health impact assessments. In a case study, we describe a quantitative health impact assessment of traffic-related air pollution and children's asthma in one of the 10% most deprived local authorities in the United Kingdom. We finally give recommendations on how future quantitative health impact assessments can explore equity issues more explicitly and systematically. We conclude that there is an urgent need to reduce the health burden of urban transport and pay particular attention to the uneven burden among different populations.