While cities are often seen as pollution hotspots, studies increasingly reveal significant air pollution in rural towns and villages, primarily from wood heating.

Yet, government monitoring networks largely focus on urban areas, neglecting the air quality experienced by the 20-30% of people in the UK and Europe living in the countryside.

To address this oversight, scientists conducted a winter study in Retje, a Slovenian village of 690 residents nestled in a valley.

Dr. Kristina Glojek from the University of Nova Gorica described the picturesque village as a scene fit for a Christmas card: “The scenery seems idyllic; a small village with a church on top of a hill surrounded by dense forest and frequently covered with snow. Yet, in the cold part of the year, the village is often enveloped in a brownish fog.”

While public buildings are heated via a district heating system, most households rely on wood-burning stoves.

The research team installed air pollution monitoring equipment in the village and on a nearby hillside. For two months, they trekked 4 miles (6 km) three times daily with measurement equipment in backpacks, covering nearly 400 miles in total.

Glojek explained some of the practicalities: “Low temperatures, early darkness, constant problems with the scientific equipment and also a lot of wildlife, including bears. These hibernate, but not the whole time. When air settled in the valley, particle pollution reached the level of the most polluted cities of the world. After walking for two hours, three times a day we could not wash off the smell. Out of 88 winter days, 34 of them exceeded the legal limits.”

Despite this data, the local perception was quite different. Glojek said: “Seventy per cent believed that air quality in their area was good, and 89% believed that wood smoke did not have a negative effect on health. All the other culprits of local pollution were mentioned, although they are practically non-existent in the area.”

Despite its reputation as climate-neutral, wood-burning is far from harmless. Cutting trees reduces carbon sinks, while burning wood releases climate-warming methane.

In Retje, the smoke contained black soot and brown particles, both capable of absorbing solar heat and contributing to warming.

Andrea Cuesta, from the Leibniz Institute for Tropospheric Research and part of the research team, said: “We found that the forcing efficiency was positive [warming] and that bright surfaces, such as fresh snow, might be more susceptible to the wood-burning smoke, which could accelerate melting.”

Similar studies in Ireland and Germany show that villages and small towns are disproportionately affected by winter air pollution from wood and solid-fuel heating.

In Scotland, a proposed ban on wood stoves as the primary heat source for new homes and extensions was recently reversed, sparking further debate about rural heating practices and their environmental impact.

Prof Jill Belch, from the University of Dundee, said: “Instead of allowing wood-burning in new builds, rural exceptions, reliable grid expansion, with more generous solar, heat pump, and insulation grants for those off grid or with unreliable power could reduce the significant health hazard of wood-burning for all our people.”