Evaluation of the relationship between allergic diseases in school children at Seoul's roadside elementary schools and air pollution

An elementary school is an important public place for children and it is where they spend most of their days. The objective of this study was to survey the environmental conditions at schools and to assess the relationship between air pollution and allergic diseases using the International Study of Asthma and Allergies in Childhood questionnaire. Nine elementary schools were selected and subsequently classified into three groups. The selection included two schools with no traffic-related or other pollutants, four schools situated near roads with six lanes, and three schools situated near beltways. Allergic diseases were assessed in a total of 6301 students. School zones with critical exposure to pollutants were selected within each school and were evaluated based on the levels of particulate matter, fine particulate matter, ozone, carbon monoxide, carbon dioxide, nitrogen dioxide, sulfur dioxide and black carbon. O₃ and PM₁₀ exposures were significantly associated with the prevalence of lifetime symptoms and diagnosis of asthma. O₃ and PM₁₀ exposures were also associated with lifetime symptoms, diagnosis, and 1-year physician diagnosis prevalence of allergic rhinitis. BC exposure was significantly associated with the rates of 1-year treatment of disease for allergic rhinitis. For schools located near sources of air pollution, the prevalence of lifetime symptoms for atopic dermatitis was significantly increased. Some symptoms of allergies were significantly increased at schools surrounded by a higher traffic volume. This study provides additional evidence that exposure to school zone air pollutants and traffic volume put school children at risk for childhood allergic diseases. Thus, strategies and actions are necessary to protect children in schools from exposure to environmental pollutants. In addition, future analysis to evaluate the relationship between traffic-related air pollution and the development of allergic diseases at more advanced ages are needed to confirm or refute these associations.