Semi volatile organic compounds and flame retardants: Occurrence in indoor environments and risk assessment for indoor exposure

The first part of the project presented in this publication reviews the occurrence of semi-volatile organic compounds (SVOCs) and flame retardants in commonly used building and furnishing materials in Finland. SVOCs included in the review are plasticisers, like phthalates, flame retardants (FRs), like brominated organic compounds and organophosphate esters. In addition, polyaromatic hydrocarbons (PAHs), which are constituents in coal tar/ creosote and have been used for moisture proofing in structures, are also discussed. On the basis of present knowledge, risk assessment for exposure indoors is presented. In addition, sources of SVOCs and the waste potential in the old building stock are clarified. The knowledge for the review was gathered from housing statistics, building product statistics, the chemical registry at The National Product Control Agency's (STTV), The National Board of Antiquities and Historical Monuments in Finland, Finnish Environment Institute (SYKE), and from interviews with the construction product industry. In the second part of the project, SVOCs were measured from a total of 13 building materials including flooring materials, paints, insulations and a levelling agent (screed). Both short and long term (up to 60 days) emissions were measured by modifying the existing standard sampling method for the measurement of volatile organic compounds (VOCs). Emissions were measured at room temperature 23 °C and at 40 °C. The elevated temperature was considered to simulate real life situations, such as when a floor structure has heating or a surface gets warmed up by direct sunlight. The results showed that the initial specific emission rates (SER) of SVOCs are typically low, less than 5 µg/m2h. An exception was newly prepared foam type polyurethane insulations, which emitted SVOCs up to 65 µg/m2h. The SVOC SERs were higher at 40 °C, up to 165 µg/m2h. No phthalates were detected from the air samples collected at room temperauture during the 60 -day test period. However, 218 µg of a phthalate compound was detected from the solvent used to rinse the walls of the chamber that was used to measure the PVC sample. Also, 72 ng of the fire retardant hexabromocyclododecane (HBCD) was detected from the rinsing samples of the chamber used for measuring the expanded polystyrene (EPS) insulation for FR applications. A commonly used FR, Fyrol PCF (Tris (2-chloroisopropyl) phosphate, TCCP) was detected from air samples taken from the polyurethane insulation (foam type) at 24 µg/m2h (as toluene equivalent) after 120 minutes at 40°C. Boron was detected from air samples from the cellulose based insulation material at 0.3-5 µg/m3. The study showed that SVOCs and FRs are emitted at low levels at room temperature from common building materials. However, the variety of compounds emitted and emission ranges varied markedly depending on which building product was measeured. SVOC (and VOC) SERs increased markedly when the temperature increased to 40 °C. In real life, such temperatures can be reached on surfaces with direct sunlight during the summer or in cases when floor heating is used. Consequently, exposure assessments for SVOCs in such environments can be assessed better based on the emission results collected during this project. Exposures at room temperature were esitimade to <0.1 - <2 µg/kg day. However, the migration of FRs and SVOCs into indoor air is probably less from building materials that are inside a structure, e.g. insulation, which decrases exposure to these compounds indoors.