Comprehensive indicators of traffic-related premature mortality

Motor vehicle circulation is associated with multiple social benefits; nevertheless, it is widely acknowledged that it also produces a variety of adverse health effects, of which the most relevant are associated with mortality from road accidents and exposure to atmospheric pollution. Though in Chile these impacts have been quantified and evaluated independently, no indicators have been developed so far to account for this activity's global impact on public health, or to express the individual impact that can be attributed to each vehicle category. In order to fill this void, the present study aimed at designing and quantifying indicators that account for the global impact on health that different motor vehicle categories impose on Chilean society. Health impact was quantified as the number of expected premature deaths caused by road accidents and exposure to atmospheric pollutants. Total premature mortality was understood as the total annual deaths that occurred as a consequence of road accidents and the exposure to O-3 and PM2.5 derived from traffic-related emissions of its precursors. All estimations were made considering Chile's Metropolitan Region in 2005 as a basic scenario. Differentiated indicators were obtained for 15 vehicle categories as a function of different parameters: traveled kilometer, vehicle, and vehicle lifetime. According to our results, when the health impact of traffic accidents and exposure to traffic-related air pollution are considered simultaneously, major differences were observed with the indicators traditionally used by regulators involved in the traffic-related decision-making process. The implications of our results on risk management strategies are discussed.