How to Finally Clear Your Home of Lingering Wildfire Chemicals

Wildfire smoke has billowed across large swathes of the United States and Canada this year with potentially long-term impacts on human health. Researchers from Colorado State University have now found that dangerous particulates from this smoke can linger in our homes for weeks, or even months, after the initial blaze.

But there is hope: their study, published in the journal Science Advances on October 13, found that simple cleaning procedures can help remove these hazardous chemicals.

"Particles [in wildfire smoke] are known for their adverse health impact to human beings," first author Jienan Li told Newsweek. "Some particles smaller than 10 micrometers can get into our lungs and even bloodstream. Exposure to particles induces cough and worsens asthma. Smaller particles like PM2.5 and PM0.1 are also linked to other diseases like diabetes, cancer, cardiovascular disease and hypertension.

"Our research is mainly about volatile organic compounds (VOCs) in wildfire smoke, [but] gases from wildfires can also be toxic."

These hazardous particles can enter our homes through cracks in the walls, floors and ceilings and attach themselves to our countertops, carpets and curtains. "VOC and particle emissions also occur from in-home cooking and candles if those smoke cannot be ventilated out effectively," Li said.

To study the movement of smoke particulates into and around buildings, the team burned pine wood chips in a net zero energy testing facility operated by the National Institute of Standards and Technology in Maryland. They then studied the air quality levels and surface conditions in the facility before and after opening windows, cleaning, and using the facility's built-in air cleaning system.

What they found was that simply cleaning the surfaces around the home-like facility made a huge impact on the amount of lingering wildfire smoke.

"Surface cleaning can help to remove a certain number of contaminations permanently, this can be very useful when the house is heavily polluted by the wildfire smoke," Li said.

Vacuuming, mopping, and dusting the surfaces was much more effective than portable air cleaners and was a more permanent solution than opening the windows.

"Ventilation can help improve indoor air quality quickly if the outdoor air quality is good, but as soon as we close windows and doors, the VOC concentration will go back quickly," Li said. "When the outdoor air is polluted, we definitely cannot open doors and windows to enhance the ventilation."

In their experiments, the team used a simple cleaning solution recommended by the Red Cross, based on trisodium phosphate and multipurpose cleaner.

"We do not recommend any products [specifically], and we note that cleaning solutions can be sources of chemical air contaminants of concern or even induce additional chemical reactions that create toxic byproducts, as is the case for chlorine-based cleaners," Li said.

As for any mops or sponges used for these surfaces, they should be washed or thrown away after us to avoid unwanted contamination. "They can be emission sources for VOCs and deposited particles if we just put them indoors after cleaning," Li said.

As wildfires increase around the globe, understanding how to protect ourselves and our homes from their negative effects will be an important focus for public health in the future.

"As we continue this research, we would like to know just how effective different cleaning approaches are and when residents should move from relatively simple steps like using commercial cleaning supplies for mopping to more drastic steps like replacing the drywall altogether," Delphine Farmer, senior author on the study, said in a statement.