Exposure to environmental chemicals relevant for respiratory hypersensitivity: European aspects

The need for assessing air pollution exposure on the individual and population levels is urgent, as health effects are observed at concentrations even below existing air quality guidelines (AQG). Typical European concentrations and trends over time of four main air quality indicators (nitrogen dioxide, sulphur dioxide, ozone and particulate matter) are presented, together with their revised WHO AQG. In order to describe concentrations of pollutants each individual and population groups are exposed to, methods have been developed that estimate these concentrations using different forms of modelling. The EXPO model, developed to assess European exposure to air quality contaminants, estimates exceedances of AQG in many European cities and serves as an initial step in estimating European population exposure. Individual pollution exposure is estimated by measuring/estimating pollution concentrations at the home and/or by following and integrating exposure in different micro-environments. Examples of these methods are presented.