Formaldehyde in the ambient atmosphere: from an indoor pollutant to an outdoor pollutant?
Formaldehyde has been discussed as a typical indoor pollutant for decades. Legal requirements and ever-lower limits for formaldehyde in indoor air have led to a continual reduction in the amount of formaldehyde released from furniture, building materials, and household products over many years. Slowly, and without much attention from research on indoor air, a change of paradigm is taking place, however. Today, the formaldehyde concentrations in outdoor air, particularly in polluted urban areas, sometimes already reach indoor levels. This is largely a result of photochemical processes and the use of biofuels. In the medium term, this development might have consequences for the way buildings are ventilated and lead to a change in the way we evaluate human exposure.
Department of Material Analysis and Indoor Chemistry, Fraunhofer WKI, Bienroder Weg 54 E, 38108 Braunschweig, Germany. tunga.salthammer@wki.fraunhofer.de
Tunga
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Salthammer