The popular image of wood burning and wood smoke now is not unlike how cigarettes used to be viewed, when popular entertainment and advertisements portrayed smoking in a positive light.
There was a time not long ago when it was normal for most public places to be filled with cigarette smoke: restaurants, offices, airplanes and even hospitals and doctors’ waiting rooms.
Smoking was the norm, and people who didn’t smoke were expected to breathe cigarette smoke wherever they went.
Wood smoke resembles tobacco smoke
Both wood smoke and cigarette smoke are the products of burning plant material, which is also sometimes referred to as biomass.
Wood smoke has most of the same carcinogens, mutagens and teratogens (substances linked to birth defects) that are in tobacco smoke, but in much greater quantities.
Virtually all of the adverse health effects that have been associated with secondhand cigarette smoke have also been linked with exposure to wood smoke.
As a study on asthmatic children in Seattle noted, “wood smoke resembles environmental tobacco smoke, for which numerous studies have shown deleterious effects on the respiratory health of children.”
In an article about wood smoke pollution on the Medical Journal of Australia's website, respiratory physician Dr. James Markos notes there is no safe level of wood smoke exposure. “It is identical to the risk of lung cancer from passive smoking.”
Dr. Rob Phair, Vice President of the Rural Doctors Association of Victoria, wrote in the magazine of the Australian Medical Association Victoria, “The discussion about wood heaters should resemble the discussion about tobacco smoking, which we have been having with patients for many years. Smoking in public places is recognised as harmful to public health. The same recognition should be extended to domestic wood heaters.”
Smoke is smoke
Today, the scientific evidence is solid and leaves no doubt: breathing smoke of any kind causes and worsens an alarming number of serious health problems, and it increases the risk of premature death.
Wood smoke is worse
There is nothing special about wood smoke that makes it less harmful to inhale than cigarette smoke. In fact, research evidence tells us it is worse.
For example, extracts of particulate matter “containing substantial quantities of wood smoke” were found to be 30 times more potent at inducing tumors than extracts of cigarette smoke condensate in a laboratory study.
Mucus production in our airways increases in response to breathing in harmful substances such as smoke. In people with chronic lung diseases such as asthma and COPD, this process persists and can result in serious health outcomes, including blocked airways. Wood smoke is more potent than cigarette smoke in triggering this process.
The toxic free radicals in wood smoke remain chemically active forty times longer than those from cigarette smoke.
Wood burning has an image problem
Today, it is widely understood that secondhand smoke from cigarettes is unhealthy to breathe.
Images, for example, of children breathing secondhand cigarette smoke are never now seen in a positive light. But the same is not true for wood smoke.
An air quality agency in southern California has determined that a wood-burning beach fire ring—equivalent to a fire pit—emits as much fine particle pollution as 800 cigarettes. Yet, images of children with fire pits are seen as positive, if not wholesome.
Similarly, highly polluting wood-burning fireplaces, wood stoves and smoking chimneys are frequently featured in romanticized wintertime imagery, while in reality wood burning in winter is a large source of health-damaging air pollution in many communities. Heating a home with wood for a week can create more toxic chemicals than in the smoke from a million cigarettes (PDF).
There is a disconnect today between the reality of wood burning and wood smoke—which has health effects very much like those from secondhand cigarette smoke—and the associations we have with wood burning.
It’s time to start making the connection. Smoke is harmful to breathe, no matter what form of burning plant material it comes from.