Definitions: Concentration, Exposure, and Dose

Human exposure to outdoor air pollution is believed to cause severe health effects, especially in urban areas where pollution levels often are high, because of the poor dispersion conditions and high density of pollution sources. Many factors influence human health, and a good assessment of human air pollution exposure is, therefore, crucial for a proper determination of possible links between air pollution and health effects. Assessment of human exposure is, however, not straightforward, and this is the background for the present paper, which recommends how to carry out such assessments. Assessment of human exposure to air pollution may be carried out by use of: