What You Should Know About Wildfire Smoke in Homes

When wildfires spread through neighborhoods, they burn cars and houses and everything around them—electronics, paint, plastic, furniture.

Research shows that its mix chemical release When man-made substances such as these burn are different and potentially more toxic than those released during vegetation fires. Smoke and ash can drift under doors and around windows in nearby homes, bringing chemicals that are absorbed into furniture, walls and other indoor surfaces and continue to off-gas for weeks to months.

When people return to smoke-damaged homes after wildfires, there are also There are several steps they can take To protect their health before starting to clean.

High levels of metals and VOCs

In 2021, after the Marshall Fire broke out in areas near Boulder, Colorado, my colleagues and I at the University of Colorado and labs heard from many residents who were concerned about ash and The lingering smell inside their home That was otherwise flame alive.

In the house that my colleagues were able to quickly check, they found High levels of metals and PAHs – polycyclic aromatic hydrocarbons – in ash. We also found elevated VOCs – volatile organic compounds – in airborne samples Some VOCs, eg Dioxin, Benzene, Formaldehyde And PAHsMay be toxic to humans. Benzene a Known carcinogen.

At that time, we found no information on the physical health effects of people returning to smoke-damaged homes after wildfires. So, looking for patterns, we of residents surveyed Fire damage occurred six months, one year and two years after the fire.

Six months after the fire we still found it Many people were reporting symptoms which is linked to health risks associated with smoke and ash from fires.

More than half (55%) reported experiencing at least one symptom six months after the fire attributed to the Marshall Fire. The most common symptoms reported were itchy or watery eyes (33%), headache (30%), dry cough (27%), sneezing (26%) and sore throat (23%).

All of these symptoms, as well as having a strange taste in one’s mouth, were associated with people reporting that their homes smelled different when they returned home a week after the fire.

Many survey respondents said that the smell has diminished over time. Most often attribute odor improvements to cleaning surfaces and air ducts, replacing furnace filters, and removing carpets, textiles, and furniture from the home. Despite this, many still had symptoms.

We also found that being near a large number of burned structures was associated with these health symptoms. We found that for every 10 additional destroyed buildings within 820 feet (250 meters) of a person’s home, there was a 21% increase in headaches and a 26% increase in having a strange taste in their mouth.

These symptoms are what might be expected from exposure to the chemicals we found in the ash and measured in the air We were able to study the smoke-damaged houses the depth

Chronic symptoms and questions

There are still many unanswered questions about the health risks of smoke- and ash-damaged homes

For example, we don’t yet know what the long-term health effects might be for people living in a home with lingering gases from wildfire smoke and ash. We found a significant Decrease in human population Reported symptoms one year after the fire. However, 33% of people whose homes were damaged and responded to the follow-up survey still reported at least one symptom that they attributed to the fire. About the same percentage showed at least one symptom two years after the fire.

We also could not measure the level of VOCs or metals that each individual was exposed to. But we think that reports of changes in the smell of a person’s home a week after a fire demonstrate the possible presence of VOCs in the home. This has health implications for people exposed to smoke or ash from wildfires in their homes.

Tips for protecting yourself after a fire

There is a fire Increasingly houses and other structures burned as More people enter wildland-urban interface, rise in temperature And the fire season lengthens.

If you’ve survived a wildfire near your home, here’s something Steps to think about Before starting to clean:

• When you’re ready to clean your home, start by protecting yourself. Wear at least one N95 (or KN95) mask and gloves, goggles, and clothing that cover your skin. Cleaning can send some of those gases and ash back into the air.
• Keep people with heart or lung disease, older adults, pregnant women, children and pets away from the cleaning process.
• Vacuum floors, drapes and furniture. A recent scientific study How to document Clean all surfaces Reservoirs of VOCs within a home and can reduce indoor air concentrations of VOCs. When the outside air is clear, open windows to let in fresh air.
• Avoid harsh chemical cleaners as they may react with the chemicals in the ash.
• Clean your HVAC filter and ducts to prevent ash from spreading further, and change the filter monthly until the odor is gone. Portable air cleaners with carbon filters can help remove VOCs and particulates.
• If your car smells of smoke, consider changing the cabin air filter.

This is an update to an article First published on December 23, 2024.

Colleen E. ReidAssociate Professor of Geography, University of Colorado Boulder

Reprinted from this article the conversation Under Creative Commons license. read on Main article.