Wildfires can expose people to harmful airborne compounds like ash and smoke. Research has shown that even months after a fire is out, people returning to their homes may experience health problems.
A study of people affected by the 2021 Marshall Fire in Boulder, Colorado, found that many reported symptoms such as headaches, sore throats, and coughs. These symptoms were more common in homes near burned areas.
Wildfires burn both natural materials and man-made objects, which release harmful compounds like polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) into the air. These chemicals have been linked to lung and heart diseases.
After the Marshall Fire, researchers found elevated levels of these compounds in homes that were not burned but were affected by smoke. They conducted a survey with residents whose homes remained intact to understand any health symptoms caused by exposure to these chemicals.
The survey, conducted at 6 months and 1 year after the fire, found that common symptoms included itchy eyes, dry coughs, sneezing, and sore throats. Many residents also reported noticing campfire-like smells in their homes and ash inside. Those who found ash in their homes were more likely to report headaches.
Over time, cleaning and replacing damaged items helped reduce the smell and symptoms.
These findings could help guide future recommendations on how to safely return to homes after a wildfire.