VOLATILE ORGANIC-COMPOUNDS IN INDOOR AIR AND IN EXPIRED AIR AS MARKERS OF ACTIVITIES

Volatile organic compounds (VOC) are present in indoor air at concentr ations generally higher than in outdoor air. In this study VOC concent rations in the air of two classrooms differing in insulation, and in t he expired air of children in them, were investigated. Qualitative and quantitative determinations were done by gas chromatography-mass spec trometry techniques. Differences in the concentrations of VOC in indoo r air and in the expired air of the children were linked to the endoge neous or exogeneous origin of the compounds, to the activities of the children and to the quality of indoor-outdoor air exchanges.