A new BMJ investigation reveals that wood burning stoves emit dangerous levels of pollutants including arsenic, whilst the stove industry silences councils trying to warn the public.
A major investigation by the British Medical Journal has uncovered alarming levels of toxic pollutants being released into UK air from domestic wood burning stoves, including arsenic from the burning of treated construction waste. The research, which examined councils across England, also reveals that the stove industry has been threatening local authorities with legal action to prevent them from running public health campaigns warning residents about the dangers.
The investigation used Freedom of Information requests to examine 50 councils in areas with the highest concentration of wood burning stoves. Remarkably, just under a third had faced legal threats or lobbying from the Stove Industry Association when attempting to communicate health warnings to their communities.
“We’re finding not only chemicals from wood burning, but we’re finding arsenic in the air as well,” explains Rebecca Coombes, head of journalism at the BMJ, in a podcast discussion of the findings. This arsenic originates from the burning of construction waste, particularly timber that was treated with arsenic to prevent woodworm—a common practice in the UK until approximately 15 years ago. When householders burn old timber in their stoves, they inadvertently release this carcinogenic substance into the air above their homes and communities.
The scale of the problem is significant. Figures suggest that one in 10 homes in England now owns a wood burning stove, with popularity concentrated in urban areas. Government emissions data show that domestic wood burning is a major source of fine particulate matter known as PM2.5—particles of 2.5 micrometres or smaller that the World Health Organization classifies as a known carcinogen. In the UK, wood burning accounts for around 50 per cent of PM2.5 emissions from domestic fires, making it comparable to pollution from road transport.
The health risks associated with PM2.5 exposure are substantial and well-documented. Research cited by England’s Chief Medical Officer, Professor Chris Whitty, has shown that even the newest “eco-design” stoves emit several hundred times more pollution than a gas or oil-fired boiler. A 2020 systematic review published in The Lancet Global Health linked indoor air pollution from wood burning with heart disease, lung disease, lung cancer, strokes, stillbirth and asthma. A 2023 North American study of more than 50,000 non-smoking women found that using fireplaces or wood stoves for more than 30 days per year was associated with a 68 per cent increase in lung cancer risk.
Beyond cancer and respiratory disease, the fine particles released can enter the bloodstream and lodge in internal organs including the heart and brain, contributing to cardiovascular disease and stroke. Research from Imperial College London in 2024 linked short-term exposure to carbon particles from wood burning with increased risk of death from respiratory causes.
Despite this evidence, councils attempting to inform the public have faced aggressive pushback from the stove industry. In late 2023, eight London boroughs—Croydon, Haringey, Islington, Lewisham, Merton, Richmond, Southwark and Wandsworth—were threatened with legal action over a joint public awareness campaign highlighting the harms of wood burning. Brighton and Hove City Council faced similar pressure after launching a campaign warning that wood burning is a “cosy killer,” based on air quality data showing dramatic spikes in harmful particle pollution at 10pm, when stoves are typically lit.
The industry has employed multiple tactics to undermine public health messaging. Some councils received promotional leaflets from the Stove Industry Association claiming that wood burning provides “health and wellbeing benefits” and lowers blood pressure and stress—claims contradicted by the Royal College of Paediatrics, the Royal College of Physicians and the Chief Medical Officer. Other materials claimed there was “no scientific evidence” for adverse health effects, a position at odds with peer-reviewed research.
These intimidation tactics have had a chilling effect. Representatives of the London Wood Burning Project, a coalition of councils running campaigns, reported that the legal threats had created “a degree of worry about what happens if we are challenged, even if we’re confident that the science backs up what we are saying.” This has deterred some local authorities from communicating established health risks.
The government is now taking action. A public consultation is proposing cigarette-style health warnings on new wood burning stoves and tighter controls on emissions. The Department for Environment, Food and Rural Affairs stated that “dirty air robs people of their health and costs our NHS millions each year,” whilst committing to new targets to cut air pollution by a third by 2030, including reduction of fine particulate matter exposure.
Professor Chris Whitty emphasised the urgency of the issue, noting that wood burning stove growth in urban areas is now reversing many decades of progress in air quality. “The growth of wood burning stoves in urban areas contributes a significant and growing proportion of air pollution,” he told the BMJ.
Source: @bmj_latest
Key Takeaways
- Wood burning stoves release PM2.5 (fine particulate matter) classified by the WHO as a known carcinogen linked to lung cancer, heart disease, stroke and asthma
- Burning treated construction waste releases arsenic into the air above homes and communities
- The stove industry has threatened legal action against councils attempting to run public health campaigns
- Even new “eco-design” stoves emit significantly more pollution than gas or electric heating systems
- The UK government is consulting on cigarette-style health warnings for new stoves
What This Means for Kent Residents
For residents across Kent, this investigation has clear local implications. With an estimated one in 10 English homes now containing a wood burning stove, many households in the county may be unknowingly contributing to air pollution in their areas. Those living in urban areas of Kent, particularly around Medway and larger towns, should be aware that the pollutants released from stoves—including arsenic, polyaromatic hydrocarbons and fine particulates—can accumulate in still, cold winter air.
Kent and Medway NHS Trust advises that residents with existing respiratory conditions, cardiovascular disease, asthma or living with vulnerable family members should consider the health impact of wood burning. GPs and respiratory clinicians across Kent can provide advice on safer heating alternatives. Those concerned about air quality in their local area should check their council’s air quality monitoring data and contact their local authority about participation in clean air campaigns. The approaching government decision on health warnings will likely be implemented nationally, but individual households can act now by switching to cleaner heating methods or, if they must use their stove, ensuring they burn only properly seasoned wood and never treat waste timber.
