Because wood is natural and trees can be replanted, some people believe that burning wood is better for the environment than using fossil fuels. However, wood burning has a large negative impact on the environment and on our climate.
Localized carcinogenic pollution
Wood burning creates large quantities of localized outdoor air pollution, which has been declared a Group 1 human carcinogen by the International Agency for Research on Cancer.
It also emits toxins such as PAHs, dioxins, benzene, mercury, and formaldehyde into our environment, to name a few. Many of these are harmful persistent chemicals that don’t readily break down in the environment and build up inside human and animal body tissues.
Wood burning vs. car exhaust
Many people know that cars are polluting, but wood stoves are much, much worse.
More emissions than from traffic
In Canada, for example, official government figures for 2022 estimate that more fine particle pollution came from residential wood burning (80,000 metric tonnes per year) than from the country’s entire transportation sector combined (24,000 metric tonnes).
Similarly, in the United Kingdom more fine particle pollution comes from wood burning than from traffic.
In a US state well known for its urban areas and traffic, New York, more primary PM2.5 comes from residential wood burning than from the state’s entire transportation sector.
Likewise in California with its notorious urban traffic, but also with relatively mild winters, the California Air Resources Board estimates that wood stoves and fireplaces contribute more PM2.5 than the exhaust of all the motor vehicles on the road combined.
(There is more information about emissions from residential wood burning on our Wood Smoke Is Particle Pollution page.)
A study of the the ecotoxicities of urban particulate matter found that wood smoke was more ecotoxic than particulates emitted from modern diesel engines.
Persistent environmental pollutants
Carried through the air on microscopic particles of wood, the toxins in wood smoke either make their way into the lungs, bloodstreams, and brains of humans and animals, or they eventually wind up on the ground and in our waterways, where they become part of our environment and our food chain. It doesn’t matter if a carcinogen such as benzene comes from a factory or from burning wood. It is the same, harmful chemical.
While in the atmosphere, some of the toxins in wood smoke chemically change and may become even more harmful. Some also contribute to ozone formation.
Wood burning and our climate
Wood burning is also not climate friendly. It emits short-lived climate pollutants such as black carbon, brown carbon and methane, and it raises levels of atmospheric CO2 during the immediate crucial time frame when controlling CO2 emissions matters most.
Trees are environmentally friendly and green. But burning them is not. Burning wood harms our health and our environment.