The main objective of this study is to analyse quantitatively the infl
uence of urban air pollution on the health of children. For this aim,
one has to analyse the concentrations of pollutants in the atmosphere,
analyse the indoor air concentrations, and conduct epidemiological su
rveys. This paper addresses the first part of the study, i.e. the appl
ication of atmospheric dispersion models for analysing outdoor air qua
lity. The area considered is Espoo, the neighbouring city of Helsinki.
Numerical results have been computed with an urban dispersion modelli
ng system, using emissions and meteorological data for the year 1990.
The computations included carbon monoxide, nitrogen oxides and sulphur
dioxide; this paper focuses on the results for nitrogen dioxide.