Urinary levoglucosan as a biomarker for residential wood smoke exposure

As part of a randomised controlled residential intervention study, levoglucosan (LG) was investigated as a biomarker for wood smoke exposure. This study was conducted among 33 children living in homes that used wood stoves for residential heating. Indoor fine particulate matter (PM_2.5) concentrations and corresponding urine samples from participants were collected during pre- and a post-intervention winter sampling periods. Interventions included the installation of an air filtration unit and a wood stove change out. Homes and children assigned to a placebo filter served as the control condition. Results showed a strong reduction in indoor PM_2.5 among the air filter homes (≈58% reduction), whereas the wood stove change out homes did not have a significant PM_2.5 reduction from pre- to post-intervention observations. Children living in the air filter homes did not show a corresponding reduction in urinary LG concentrations. Further analysis did not show an association between overall changes in indoor PM_2.5 concentrations and changes in urinary LG concentrations. These findings suggest that urinary LG is not a reliable indicator of wood smoke exposure in residential wood heating settings.