Assessing the Impacts of Traffic Air Pollution on Human Exposure and Health

It is well known that exposure to air pollution can be linked to adverse health effects in the population. This has been demonstrated in various epidemiological studies. The associations determined between pollution exposure and health effects rely on the quality of the exposure assessment. Proper assessment of human exposure is therefore crucial for a correct determination of the association between the pollution load of the population and the negative health outcomes. Focus in this chapter is on assessment of the impact of traffic generated air pollution, which is the major source of human exposure in many countries including Denmark. Some of the methodologies for assessing exposure to traffic-induced air pollution are outlined and examples from Danish exposure studies are presented. To model air pollution concentrations in streets within the Danish exposure studies, a number of locally-developed models have been applied, including the regional scale model DEHM, the Urban background model UBM and the street pollution model OSPM. These models are briefly described here. However, one of the major difficulties in exposure modelling is to obtain proper input data for the calculations. In the first Danish exposure studies, these data were obtained manually or through use of questionnaires sent to local authorities. In recent years, a GIS-based tool, AirGIS, has been applied. AirGIS takes advantage of information from the unique Danish register databases that are available together with digital maps for building images and road network. Currently, AirGIS is being applied to exposure assessment in a number of Danish epidemiological studies.