Assessing urinary levoglucosan and methoxyphenols as biomarkers for use in woodsmoke exposure studies.

A major contributor to particle concentrations in urban airsheds is domestic woodsmoke and smoke arising from wildfires or management burns. Particle concentrations in urban airsheds have been associated with a wide range of health effects. There has been little research into the contribution of biomass burning to studies of human health due to the complexity of attributing effects in the presence of multiple sources of pollutants and the variability in the nature and conditions of biomass burning. A significant advance is the use of biomarkers of exposure; methoxyphenol and levoglucosan; specific compounds produced following the combustion of lignins and detected in urine. Levoglucosan has not previously been assessed for its usefulness as a marker of human exposure. We report for the first time levoglucosan concentrations in urine. Twelve participants were recruited and asked to provide spot urine samples pre- and post-exposure to a fire training exercise. Both levoglucosan and methoxyphenol were detected in the urine of participants. There was no significant increase in these compounds post-exposure to smoke arising from the fire training. Further work is required to assess this biomarker for human exposure studies and in particular the role of diet and previous exposure.