Is the smoke from your fireplace or wood stove harmful to breathe indoors?
Yes. A 2026 study found that fireplaces and wood stoves release particles with high oxidative potential indoors, meaning they can damage your lungs and cells even at relatively low concentrations.
What's actually in it
Burning wood or coal in a fireplace or stove releases particulate matter (tiny particles) into your indoor air. These particles are a complex mix of soot, organic compounds, metals, and gases. The smaller particles (PM2.5 and PM10) are the most dangerous because they get deep into your lungs. Some are small enough to enter your bloodstream.
Even with a chimney or flue, some smoke always leaks back into the room. Opening the fireplace door, loading more wood, or having a poor draft pushes particles directly into your living space. Older stoves and open fireplaces are the worst offenders.
What the research says
A 2026 study in Environ Pollut measured the particles released by fireplaces, wood stoves, and coal stoves in real homes. The researchers didn't just count particles. They analyzed their shape, chemical makeup, and oxidative potential, a measure of how much cellular damage they can cause.
The particles from all three sources had high oxidative potential. That means they generate free radicals when they contact lung tissue, triggering inflammation and cell damage. Wood stove particles contained polycyclic aromatic hydrocarbons (PAHs), several of which are classified as carcinogens.
The composition varied by fuel type, but none were safe. Coal stove particles had more heavy metals. Wood stove particles had more organic toxins. Fireplace particles were a mix of both. All of them exceeded what researchers consider healthy indoor air quality.
Long-term exposure to wood smoke particles is linked to asthma, chronic bronchitis, reduced lung function, and increased cardiovascular risk. Children, older adults, and anyone with existing respiratory conditions are most vulnerable.
If you use a fireplace or wood stove, make sure the flue draws properly and keep the room ventilated. EPA-certified wood stoves produce far fewer emissions than older models. And never burn treated wood, painted wood, or trash, which release additional toxic chemicals.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Indoor PM(10) from fireplace, wood- and coal stove: morphology, composition, and oxidative potential in real residential settings. | Environ Pollut | 2026 |
What to use instead
Browse our vetted, non-toxic alternatives. Every product is third-party certified.
Shop Non-Toxic Home