Vehicular emission impacts on the population at the city of São Paulo

Abstract

Every day, thousands of commuters are directly exposed to air pollutants because of their proximity to the main source of pollutant emissions in an urban area: vehicles. However, studies evaluating exposure in São Paulo, the largest city in South America, are scarce. This study aims to evaluate the exposure of passengers to fine particles (PM2.5) and Black Carbon (BC) in different modes of transport (subway, bus and car) and by bicycle in different regions of São Paulo and periods of the day, and assess the dispersion of pollutants emitted by vehicles at street level. For this, mass concentration measurements were carried out on selected routes with portable instruments inside an adapted backpack. The air inlet tube was positioned at the field researcher's breathing height. The average concentration of PM2.5 and BC were higher during morning hours when compared to evening hours and the average concentration of PM2.5 were higher in the subway when compared to car and the bus averages. Higher concentrations, for both pollutants, were identified close to large avenues and intersections of busiest streets. These results are already partly published and in preparation for future publications. To assess the exposure of passengers more comprehensively in the city of São Paulo, and not only on the sampled routes, we propose to make a numerical modeling of a network of streets using the high-resolution chemical transport model MUNICH (v.1.0; Model of Urban Network of Intersecting Canyons and Highways). This part of the project was not possible to conclude in the 48 months of direct doctoral scholarship already contemplated. We then apply for another 12 months of scholarship to complete the numerical modeling part of a street network in São Paulo. (AU)