Human exposure to outdoor air pollution (IUPAC technical report)

Human exposure to outdoor air pollution is believed to cause severe health effects, especially in urban areas where pollution levels often are high, b ecause of the poor dispersion conditions and high density of pollution sour ces. Many factors influence human health, and a good assessment of human ai r pollution exposure is, therefore, crucial for a proper determination of p ossible 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. Asse ssment of human exposure to air pollution may be carried out by use of: categorical classification, application of biomarkers, analysis of air pollution data from routine monitoring networks, personal portable exposure monitors, or application of mathematical air pollution exposure models. The categorical classification is a crude indirect method based on indicato rs of exposure such as type of residence, type of job, presence of indoor s ources, etc. Categorical classification is generally inadequate for applica tion in air pollution epidemiology. Biomarkers can be a strong instrument i n assessment of health effects and provide information about air pollution exposure and dose. Use of biomarkers is, therefore, particularly useful whe n applied in combination with exposure assessment through one of the method s 3 to 5. The main focus of this paper is on these three methods for determ ination of human air pollution exposure. The optimal solution is clearly a combination of methods 2 to 5, but the available resources often set a limi t to how far the assessment is carried out, and the choice of strategy will , therefore, often be very important for the outcome of the final study. Th is paper describes how these approaches may be applied and outlines advanta ges and disadvantages of the approaches used individually and in combinatio n. Furthermore, some examples of specific applications in Denmark and the N etherlands are given for illustration.