Location, location, location–A study of factors affecting air quality in Swedish preschool yards

Abstract

Air pollution exposure is a major health concern globally. Children are especially vulnerable as their lungs and organs are still maturing and it is important to minimize children's exposure to air pollution. In this study we analyse one year of measurements of monthly average Nitrogen dioxide (NO₂) concentrations, in 17 sites around 11 preschools, to assess the influence of the preschool yard location on air quality. The urban background levels greatly affected concentrations at the preschool yards, with up to 50 % higher NO₂ concentrations in exposed central neighbourhoods compared to suburban. However, the specific placement of the preschool yard within the neighbourhood could also markedly reduce the pollution concentrations. A more exposed preschool suffered between 11 and 24 % higher concentrations compared to a nearby, more protected, preschool in the same neighbourhood. Differences of the same magnitude were also connected to the presence of barriers blocking the flow of polluted air from the source to the yard. The health implications of exposure differences were estimated to be small for each child but not negligible on a population level. Careful placement of preschool yards, especially in high-risk neighbourhoods, can improve air quality and provide a healthier environment for our children.