ASTHMATIC SYMPTOMS AND VOLATILE ORGANIC-COMPOUNDS, FORMALDEHYDE, AND CARBON-DIOXIDE IN DWELLINGS

Objectives-As a part of the worldwide European Community respiratory h ealth survey, possible relations between symptoms of asthma, building characteristics, and indoor concentration of volatile organic compound s (VOCs) in dwellings were studied. Methods-The study comprised 88 sub jects, aged 20-45 years, from the general population in Uppsala, a mid -Swedish urban community, selected by stratified random sampling. Room temperature, air humidity, respirable dust, carbon dioxide (GO,), VOC s, formaldehyde, and house dust mites were measured in the homes of th e subjects. They underwent a structured interview, spirometry, peak ex piratory flow (PEF) measurements at home, methacholine provocation tes t for bronchial hyperresponsiveness, and skin prick tests, In addition , serum concentration of eosinophilic cationic protein (S-ECP), blood eosinophil count, and total immunoglobulin E (S-IgE) were measured. Re sults-Symptoms related to asthma were more common in dwellings with ho use dust mites, and visible signs of dampness or microbial growth in t he building. Significant relations were also found between nocturnal b reathlessness and presence of wall to wail carpets, and indoor concent ration of CO2, formaldehyde, and VOCs. The formaldehyde concentration exceeded the Swedish limit value for dwellings (100 mu g/m(3)) in one building, and CO, exceeded the recommended limit value of 1000 ppm in 26% of the dwellings, showing insufficient outdoor air supply. Bronchi al hyperresponsiveness was related to indoor concentration of limonene , the most prevalent terpene. Variability in PEF was related to two ot her terpenes; alpha-pinen and delta-karen. Conclusion-Our results sugg est that indoor VOCs and formaldehyde may cause asthma-like symptoms. There is a need to increase the outdoor air supply in many dwellings, and wall to wall carpeting and dampness in the building should be avoi ded. Improved indoor environment can also be achieved by selecting bui lding materials, building construction, and indoor activities on the p rinciple that the emission of volatile organic compounds should be as low as reasonably achievable, to minimise symptoms related to asthma d ue to indoor air pollution.