The research on traffic-related air pollution (TRAP) and human health has greatly evolved in the past few decades leading to improved practices and policy decision-making in many regions. Significant advances have been made including advancing the methods to assess traffic activity, vehicle emissions, air pollution, and human exposures. Furthermore, the associations between TRAP and numerous health effects have been established in epidemiology and emerging health effects are continuously being studied. The strength of the overall body of evidence is assessed and the case for biological plausibility has been strengthened through toxicological and mechanistic studies and novel high-resolution and high-throughput technologies interrogating -omics (genomics, transcriptomics, proteomics, or metabolomics). More stringent air quality guidelines have been developed and research is yet showing health risks occurring below these thresholds. Burden of disease and health impact assessments are being used more often to qualitatively asses and quantify the health burden attributable to TRAP and demonstrate the unequal distribution of that burden according to socioeconomic and sociodemographic factors. Policy options to mitigate TRAP and its adverse health effects are expanding and so are the studies quantifying the potential impacts and the cost effectiveness of a wide range of policies. The potential health impacts of emerging technologies are being discussed and best practices to achieve TRAP reductions and a multitude of goals, beyond air quality, are now documented. We have come a long way, but there are as yet critical knowledge gaps which need to be filled offering exciting research opportunities and a pathway to push and track progress toward the goal of clean air and protection of the public’s health. This book synthesizes the state-of-the-art knowledge on TRAP and human health.
