There is something cosy and appealing about settling down next to a roaring fire in winter but, every year, nearly 61,000 premature deaths in Europe are caused by air pollution as a result of people burning wood or coal to heat their homes.
Wood-burning stoves are often considered safer, cleaner and more attractive than open fires. This may, in part, explain why from 2021 to 2022, sales of wood-burning stoves increased by 40% in the UK.
However, burning wood is not necessarily a healthier or greener alternative to coal or gas for home heating.
Wood burning produces a complex chemical mixture of fine particulate matter (PM2.5) and gases, which can be breathed deep into the lungs. The specific contents vary based on the type of stove and the type of fuel, but chemicals can include carbon monoxide, oxides of nitrogen and a range of volatile organic compounds, such as cancer-causing formaldehyde and benzene.
Exposure to wood smoke affects the heart, blood vessels and the respiratory system – and PM2.5 is considered to be the biggest threat. Wood smoke increases the risk of heart attacks and strokes and can exacerbate chronic obstructive pulmonary disease (COPD) and asthma. Exposure to PM2.5 from wood burning can also cause premature death.
Exposure to this pollution also leads to loss of work days, reduced productivity, higher expenses on healthcare and increased hospital admissions.
The risks are higher for people over 65, children, pregnant women and people with existing heart or lung conditions. Chronic wood smoke inhalation has been associated with systemic inflammation, which can make the lungs more vulnerable to infections, such as flu and COVID.
In the UK and Ireland, solid fuel heating is the main source of outdoor PM2.5 during wintertime. While wood is the dominant solid fuel in the UK, peat burning is regularly found to make the largest contribution to PM2.5 in Ireland.
Under cold, stagnant weather conditions, air pollution, even in small rural towns, can be as high as that found in very polluted parts of north India.
Exposure to outdoor air pollution caused by wood burning is an obvious health risk. But the pollution also finds its way into homes, worsening indoor air quality. Also, when lighting or refuelling a wood stove, large quantities of PM2.5 escape into the indoor air. Depending on how effective the home ventilation is, the PM2.5 levels can take hours to reduce.
