New Insights into the Detection and Chemistry of Levoglucosan in Biomass Burning Aerosol - Heterogeneous Chemistry and Novel Detection Methods

RAN ZHAO, Dylan Long, Max Loebel Roson, University of Alberta

     Abstract Number: 112
     Working Group: Aerosol Chemistry

Abstract
As climate change proceeds, wildfires are expected to gain in both frequency and intensity. Understanding the impact of wildfire emissions on climate and air quality is a pressing research topic. The most commonly used molecular tracer of biomass burning is levoglucosan (LG), an anhydrosugar arising from the pyrolysis of cellulose. LG was considered chemically stable for a long time, but research from the past 15 years has revealed chemical reactions that can occur to LG in the atmosphere. Currently, a common detection method of LG involves chemical derivatization, followed by gas-chromatography-mass spectrometry (GC-MS), which can be costly and time-consuming. Identification of unrecognized reactions LG, as well as the development of novel techniques for its detection, will continue to be beneficial for research related to biomass burning. My research group has conducted a series of experiments to better understand the emission factors and heterogeneous chemistry of LG. During the process, we also recognized the importance of establishing both advanced and low-cost measurement methods for LG. This presentation will highlight our recent discovery that particle-phase levoglucosan can undergo heterogeneous reactions with atmospherically relevant electrophiles, such as acid anhydrides. Consequently, acid anhydrides undergo reactive uptake to biomass burning materials, forming larger organic acids that can contribute to secondary organic aerosol. Further, we developed novel techniques for the detection of LG, including two-dimensional GC-MS and an innovative and low-cost method, which employs commercial blood sugar glucometer strips.