Gary Fuller

Wildfires around the northern hemisphere contribute about 10% of the United Kingdom’s particle pollution, with smoke traveling thousands of miles and affecting air quality months after fires occur. Research indicates that Russian fires were a major source in 2019, while Canadian fires dominated contributions in 2023 and remained unusually significant in 2024 and 2025. Scientists warn that climate change could increase the frequency and intensity of wildfires, making it harder for the UK to meet legal air-quality targets. They recommend limiting climate change and agricultural burning, while reducing UK emissions from traffic, heating, industry and agriculture could also reduce the formation of additional harmful particles from wildfire smoke.

A small Ohio study found that replacing gas stoves with electric models was associated with a 70% reduction in nitrogen dioxide and substantial improvements in asthma control, including fewer hospital visits, flare-ups, missed days and reliever-inhaler use. The average asthma score fell from 2.6 to 1.5 across 72 homes, an effect comparable to or greater than those reported for some asthma drugs. The study was halted early after funding cuts by the incoming Trump administration, leaving more than 1,100 planned households without the intervention. Researchers and outside experts said the findings warrant a larger controlled study and suggest indoor air quality should be considered alongside energy efficiency and decarbonisation.

Ground-level ozone rose across western Europe during June’s record heatwave, peaking in the afternoons and reaching especially high levels in Germany, the Benelux, northern Italy, Paris, Spain and the Czech Republic. Ozone forms when pollutants react in strong sunlight and can worsen respiratory illness, damage vegetation and contribute to excess deaths. Although peak concentrations were below those recorded in 1976 and 2003, average exposure remains concerning, with more than one-fifth of Europe’s agricultural land exceeding EU ozone targets in 2024. Experts say coordinated action on ozone precursors, methane, climate change and wildfire risks is needed.

Research focused on northern Italy found that fossil gas consumption fell sharply in December 2022 after Russia’s invasion of Ukraine and higher energy prices, with some households apparently switching to wood burning. Benzo[a]pyrene concentrations rose by more than 10% at 17 of 63 monitoring sites in the Po Valley. Modeling suggested that a 30% increase in wood burning could have exposed an additional 2 million people to excessive particle pollution and raised attributable deaths from 280 to 314 that month. The findings echo pollution and health problems seen in Thessaloniki during Greece’s 2012–13 financial crisis and highlight the vulnerability of air quality to energy-market volatility.

An Imperial College London study found that emergency hospital admissions among adults in central London declined after the 2017 T-charge and 2019 Ulez were introduced. Annual admission trends shifted from a 3% increase before the schemes to a 3% decrease afterward, with larger reductions for heart-related conditions and a statistically inconclusive reduction for respiratory problems. The researchers linked the improvements primarily to reduced air pollution, while acknowledging possible contributions from increased walking and cycling and lower traffic noise. They could not separate the individual effects of the T-charge and Ulez or fully distinguish them from the impact of the Covid pandemic.

A University of Leicester study tracking more than 5,000 people born in and around Bristol found that greater exposure to air pollution during pregnancy, infancy and early childhood was associated with slower lung development through early adulthood. Exposure to particulate matter and nitrogen dioxide appeared to have its greatest effect during adolescence, when lung growth accelerates. Although the differences for individual children were small and unlikely to cause immediate clinical effects, researchers warned that reduced lung capacity may lower health reserves and increase vulnerability to respiratory and cardiovascular disease later in life. The findings reinforce the importance of reducing air pollution and protecting children’s environments.

A University of Massachusetts Amherst study of air-pollution samples collected over seven winters found that higher levels of particles associated with wood burning coincided with higher lead concentrations. The evidence, including data from 22 additional US towns and adjustments for temperature, suggests the lead may come from trees absorbing it from soil rather than only from old lead-painted wood. Although measured concentrations were below US legal limits, researchers stressed that lead is harmful at any level. The findings challenge the perception of wood heating as a benign or nostalgic energy source and indicate potential risks for communities and homes that burn wood.

Research at the 2022 Commonwealth Games in Birmingham found that particle pollution around the stadium was more than twice spectators’ typical daily exposure and peaked at up to 10 times city levels before the closing ceremony. Catering outlets, particularly those preparing fried fast food, were the main source, while fireworks caused a second spike. Pollution also persisted during athletics sessions as spectators visited food outlets. Traffic controls, park-and-ride schemes, public transport, walking and cycling access successfully limited pollution from vehicles, and no tobacco smoke was detected because smoking was banned. Researchers said organisers should account for cooking emissions because poor air can affect staff, spectators and athletic performance.

A study of up to 15 years of health records from 396,000 UK Biobank participants found that air pollution was associated with earlier onset of 78 illnesses across multiple organ systems, including schizophrenia, Parkinson’s disease, dementia, high blood pressure, asthma and diabetes. The researchers estimate that reducing pollution to meet the World Health Organization’s 2021 guidelines could have prevented 539,000 years of illness among roughly 360,000 participants, yielding an average gain of just over one healthy year. Independent researcher Amy Ronaldson said the findings reinforce concerns about pollution worsening health inequalities and increasing pressure on the NHS.

Research indicates that reducing people’s vulnerability to air pollution through better healthcare, nutrition, physical activity and poverty reduction prevented about 1.7 million additional deaths in 2019. Although particle pollution improved in 139 countries between 1990 and 2019, pollution-attributable deaths rose from 3.8 million to 5.1 million because of population growth, with annual deaths potentially exceeding 10 million by 2050. Europe achieved a larger reduction in pollution-related mortality than North America despite similar pollution declines, partly because it reduced vulnerability more effectively. UK evidence shows that lower-income people experience substantially greater lung-function decline and chronic obstructive pulmonary disease risk from the same pollution exposure.

Research by scientists at the University of Galway found that smokeless coal ovoids and olive-stone briquettes produced two to three times more ultrafine particles per kilogram than wood or coal, despite generating less visible particle pollution. These particles can penetrate deeply into the lungs and include potentially carcinogenic polycyclic aromatic hydrocarbons. Measurements in Dublin and Birr showed unusually high winter evening concentrations, with Dublin levels rising after households shifted toward low-smoke fuels from 2021. The findings challenge the assumption that replacing conventional solid fuels with smokeless alternatives is sufficient to reduce health risks and support a broader strategy to address domestic air pollution.

The European Code Against Cancer is calling on governments to make air-pollution reduction part of cancer-prevention strategies. It urges the EU, national governments and local authorities to meet World Health Organization air-quality guidelines, phase out coal and biomass combustion, discourage wood burning, support cleaner home energy systems, and redesign cities to reduce motor traffic. The recommendations reflect evidence linking particulate pollution to tens of thousands of European lung-cancer cases and to other cancers, while also urging protections for vulnerable groups and personal measures such as using public transport and avoiding polluted routes.

A Northwestern University study estimates that residential wood burning causes 8,600 premature deaths annually in the US, despite wood being the primary heating source in only 2% of homes. Wood burning produces 21% of wintertime particle pollution and affects urban and suburban populations as well as rural areas, with pollution accumulating in mountainous regions. People of colour experience greater exposure and health harms despite burning less wood, highlighting environmental-justice concerns. Researchers advocate transitioning homes to cleaner or non-burning heating systems. Similar risks are reported in the UK, where residential wood and coal burning contributes to nearly 2,500 avoidable deaths each year and wood-stove use is increasing.

A study of 53 primary schoolchildren in Anglesey, Wales, found that children in non-smoking homes with wood burners experienced average indoor particle pollution of about 13 micrograms per cubic metre, compared with 3.5 micrograms in homes without wood burners. Homes were the largest source of children’s daily exposure, with wood burning, indoor smoking and cooking contributing more pollution than school or commuting. Pollution sometimes persisted overnight in bedrooms when fires were left burning or smouldering in poorly ventilated homes. Rural children experienced more pollution than urban children, which researchers linked to higher rates of wood burning. The findings add to concerns about respiratory and cancer risks associated with domestic wood burning, while the UK government is consulting on health warnings for new stoves and solid fuels.

Research by the Paul Scherrer Institute finds that winter particle pollution in the Balkans, particularly Sarajevo, is among the worst in Europe and can exceed levels recorded in Beijing. Mobile monitoring found pollution above the World Health Organization’s daily guideline 66% of the time, with residential emissions from wood, coal and rubbish burning identified as major sources. An old vehicle fleet and restaurant cooking also contribute. Researchers support plans to reduce solid-fuel heating by 90% by 2033, alongside insulation, cleaner heating systems, stove inspections and public information.

Research measuring emissions from 38,000 vehicles in Milan and York found that exhaust-pipe placement significantly affects pedestrians’ exposure to pollution. Cars with exhausts near the kerb caused about 40% more pollution at the pavement than those exhausting toward the centre of the road; positioning all diesel-car exhausts roadward could reduce pollution at UK road edges by 21%. Diesel vehicles remained the dominant source of exhaust pollution, while the most polluting cars emitted substantially more nitrogen oxides and particles than typical vehicles. The findings support stricter vehicle inspections and real-world emissions monitoring, and indicate that newer diesels have improved but still vary considerably by vehicle and manufacturer.

Indoor air pollution can build up in homes, particularly during cooking, wood-stove use, cleaning and exposure to secondhand tobacco smoke. Research in UK homes found sharp pollution spikes when wood-burning stoves are lit, refuelled or tended, while a study of 310 Bradford homes identified cooking—especially frying—as the largest source of particle pollution. Researchers recommend improving ventilation, using extractor fans while cooking, limiting stove refuelling, opening stove doors briefly and slowly, and avoiding fires when children or vulnerable people are nearby. Wood and coal smoke can also affect neighbours, with about 15,000 annual complaints reportedly made to local councils.

A study by French researchers, including scientists from Université Paris Cité, found that airline passengers encounter very high concentrations of ultrafine particles and black carbon while boarding, taxiing and approaching airports, although cabin pollution is low during cruising altitude. Average ground-level concentrations exceeded the World Health Organization’s threshold for high exposure. The findings raise health concerns for passengers, airport workers and nearby communities, as ultrafine particles have been linked to lung inflammation, cardiovascular problems, impaired fetal growth and premature death. Pollution from major airports such as Paris Charles de Gaulle, London Gatwick and Heathrow can spread several kilometres into surrounding urban areas, while research on airport workers remains limited.

Aircraft-based measurements found that 8 of 19 ships exceeded permitted sulphur limits in open ocean waters in 2019, while 5 of 78 breached stricter limits in 2021–22. The tighter emissions-control zone in the English Channel and North Sea was largely effective, but 2 of 33 ships still exceeded limits. Researchers said the findings show regulations can reduce pollution while highlighting shipping as an increasingly important source of local air pollution as road vehicles become cleaner. A new emissions-control area around the western UK and north-east Atlantic is expected to take effect in 2027.

Analysis of pollution-monitoring data in London found unusual evening particle pollution peaks during the UK’s August 2020 Eat Out to Help Out scheme. The chemical signatures pointed to restaurant cooking, including wood and charcoal fuels, rather than increased traffic, and the pattern continued into September and October. Researchers say commercial cooking accounts for about 8% of London’s particle pollution, potentially more when solid fuels are included, and argue that regulators should treat commercial kitchens as a significant and solvable source of urban air pollution.

An international study published in Nature found that reducing pollution from road traffic and domestic wood burning could be more effective for improving health than targeting particle concentrations alone. Researchers assessed the oxidative potential of more than 11,000 air samples from 43 locations in six European countries, finding that pollution near roads was about three times more toxic than rural air and that toxicity was highest in winter and in poorly ventilated valleys. Sarajevo recorded particularly high toxicity because of wood heating, older vehicles and its valley geography. The findings indicate that policies must target the most harmful sources, including tyre, brake and road wear, since reducing overall particle levels has not always reduced pollution toxicity.