An approach to management of critical indoor air problems in school buildings

Ulla Haverinen,1 Tuula Husman,1 Mika Toivola,1 Jommi Suonketo,2 Matti Pentti,2 Ralf Lindberg,2 Jouni Leinonen,3 Anne Hyvärinen,1 Teija Meklin,1 and Aino Nevalainen1

1National Public Health Institute, Laboratory of Environmental Microbiology and Unit of Epidemiology, Kuopio, Finland; 2Tampere University of Technology, Laboratory of Structural Engineering, Tampere, Finland; 3Korpilahti Town, Korpilahti, Finland


This study was conducted in a school center that had been the focus of intense public concern over 2 years because of suspected mold and health problems. Because several attempts to find solutions to the problem within the community were not satisfactory, outside specialists were needed for support in solving the problem. The study group consisted of experts in civil engineering, indoor mycology, and epidemiology. The studies were conducted in close cooperation with the city administration. Structures at risk were opened, moisture and temperature were measured, and the causes of damage were analyzed. Microbial samples were taken from the air, surfaces, and materials. Health questionnaires were sent to the schoolchildren and personnel. Information on the measurements and their results was released regularly to school employees, students and their parents, and to the media. Repairs were designed on the basis of this information. Moisture damage was caused mainly by difficult moisture conditions at the building site, poor ventilation, and water leaks. Fungal genera (concentrations <200 colony-forming units (cfu)/m3, <3000 cfu/cm2) typical to buildings with mold problems (e.g., Aspergillus versicolor, Eurotium) were collected from the indoor air and surfaces of the school buildings. Where moisture-prone structures were identified and visible signs of damage or elevated moisture content were recorded, the numbers of microbes also were high; thus microbial results from material samples supported the conclusions made in the structural studies. Several irritative and recurrent symptoms were common among the upper secondary and high school students. The prevalence of asthma was high (13%) among the upper secondary school students. During the last 4 years, the incidence of asthma was 3-fold that of the previous 4-year period. Key words: asthma, health effects, moisture damages, mold, questionnaire, respiratory symptoms. -- Environ Health Perspect 107(suppl 3):509-514 (1999).