Evaluating the Use of Indoor Residential Wipe Samples Following a Wildfire

Abstract

The Las Conchas wildfire that burned in New Mexico between 26 June and 3 August, 2011 was one of the largest in state history. In addition to burning nearly 160,000 acres, smoke from the fire significantly impacted downwind communities. In an effort to quantify the extent of smoke exposure to indoor environments, wipe samples were collected inside of 64 homes located throughout the north/central region of New Mexico. These wipe samples were analyzed for char and ash (indicators of biomass smoke) using Polarized Light Microscopy, with the results plotted in Google Maps. Out of the 64 residences that were investigated, char was detected from within 78% of the homes. Ash was not measured from any of the wipe samples. Mapping of these results demonstrates the far-reaching impact that smoke from the Las Conchas wildfire had on downwind communities, as indoor wipe samples from homes up to 50 kilometers from the fire tested positive for char. This project also demonstrated the usefulness of collecting wipe samples to retrospectively assess wildfire smoke impacts on indoor environments in lieu of expensive indoor air sampling campaigns