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Particles and indoor chemical reactions. Particles and indoor chemical reactions. Particles and indoor chemical reactions. Chemical reactions = ozone and UV-initiated reactions in gas-phase and on material surface
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Particles and indoor chemical reactions Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Chemical reactions = ozone and UV-initiated reactions in gas-phase and on material surface Particles = solid or liquid aggregates of compounds suspended in air (aerosol) Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Chemical reactions I: • Nitrate radical chemistry • UV-light: influence on emission • New methods to measure multifunctional compounds • Surface chemistry of materials • Museum showcases • Full scale measurements under realistic conditions • Field measurements • Bioassays Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Chemical reactions II: • Nitrate radical chemistry competetive with O3 and OH organic nitrates and PANs • PANs and organic nitrates are formed at low ppb level • SOA are associated with nitrates and PANs • Many new multifunctional oxygenated compounds from surface chemistry - Surface chemistry C1, C8-C10 aldehydes • Transport uptake is a combination of material and coated surface uptake; formaldehyde formation predicted • Reaction probability of O3 appears to be higher for on surfaces than in the gas-phase – increased humidity reduces probability Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Chemical reactions III: • Acids are formed in showcases • Air fresheners and fragrances form formaldehyde and ultrafine particles in full scale chamber • ”Photocatalytic” paints form a number of secondary products (aldehydes) • Limonene and formaldehyde are associated in buildings • Lighting may influence production of secondary products and SOA • Pb may emit due to ozone exposure of material surface Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Particles I: • Transport from outdoor environment • Indoor sources • combustion processes • heaters • candles and incenses • smoking • cooking • equipment – laser printers • Resuspension of particles Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Particles II: • Background level of particle numbers and PM often related to urban background concentrations • Emissions from indoor sources • burning incenses may be a potential health problem • kerosene heaters are strong sources of ultrafine particles • laser printers may emit particles – large variation in strength • Fundamental studies of • emissions from daily activies • transport between rooms and influence of ventilation • Characterisation of particle composition and properties by ”new” advanced techniques Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions Particles III: • Respiratory tract deposition of candle smoke particles depends on both size and hygroscopicity • Resuspension of particles • is inversely related to particle diameter • influence of foot motion and turbulence • Carpets may increase particle deposition rate • Nanofilm products emit nanoparticles during use • Ultrafine particles from ozone/limonene reactions appear not to be responsible for acute airway effects Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions2011? • Relevant exposures and doses • Need to know health effects of • formaldehyde • SOA • nanoparticles and ultrafine particles • which properties make a particle toxicologically relevant? • Need to know odor impact of aldehydes • Identification of health relevant species/proxies by: • Study of relevant health effects by bioassays • Human exposure studies under realistic conditions to confirm bioassay findings • What is the health risk at realistic conditions? Indoor Air 2008 Mariane Glasius and Peder Wolkoff
Particles and indoor chemical reactions2011? • Less what? • A bit more why? • And a lot more • what does it mean for our health? Indoor Air 2008 Mariane Glasius and Peder Wolkoff