New techniques for the measurement of wood smoke marker compounds

Wood smoke, released from residential wood combustion or from prescribed or wild fires, comprises a significant fraction of fine particulate matter in many settings. Quantifying this impact, however, is a challenge. In recent years, efforts have increasingly focused on the use of the sugar anhydride, levoglucosan, as a wood smoke tracer. Measurement of levoglucosan is typically completed by organic solvent extraction of high volume filters followed by chemical derivatization and analysis by gas chromatography/mass spectrometry. This method is labor intensive, expensive, and presents some difficulty with respect to species recovery from sample filters. Work is under way in our laboratories to develop alternative techniques for improved analysis of levoglucosan at lower cost. The ultimate goal of these approaches will be to permit more widespread, accurate measurement of levoglucosan and related compounds in order to improve our understanding of the routine influence of wood smoke on air quality. The techniques being tested all feature aqueous extraction of levoglucosan from sample filters followed by analysis by a biosensor method, by high performance liquid chromatography (HPLC) with electrochemical detection, or by capillary electrophoresis with electrochemical detection. The performance and suitability of each technique for levoglucosan analysis will be reviewed.