‘More toxic than car exhaust’: What’s the solution to Europe’s wildfire air pollution problem?

Tackling air pollution and climate change together could save lives and boost economies, UN reports show. Climate change-driven wildfires and heatwaves are worsening air pollution, with damaging consequences for nature and human health, according to the World Meteorological Organization (WMO). Global warming is making these events worse as they release microscopic airborne pollutants that risk undermining international efforts to improve air quality, the United Nations' weather and climate agency warned on Monday (7 September). "Extreme wildfires are increasing, leading to big health consequences because of the high toxicity of smoke," the WMO said in a statement accompanying its latest annual Air Quality and Climate Bulletin. "Whilst regulations in Europe and North America have reduced industrial and transport PM2.5 emissions, exposure to fire-related PM2.5 has increased." Particulate matter PM2.5 is composed of microscopic particles and droplets of less than 2.5 micrometres in diameter, which is a health hazard because it can penetrate deep into the lungs and bloodstream. It is emitted by fossil fuel-driven industrial activities, farming, domestic heating and transport, as well as by wildfires and dust storms. The report said the world needs to better monitor air pollutants such as aerosol – including black carbon and microplastics – fine particles and ground-level ozone. These pollutants "are not sufficiently monitored even though they are widespread and are potentially harmful to ecosystems", the WMO said. "[We need] complementary and coordinated policies on air quality and climate because they cannot be dealt with in isolation." Powerful wildfires are releasing toxic smoke "Air quality and climate change can't be dealt with separately. If one worsens, the other does too," says Lorenzo Labrador, from the WMO's Global Atmosphere Watch network of scientists. "In places where there are relatively powerful forest fires, we find a lot of fine particle pollution," he says. Microparticles generated by burning vegetation are "much more toxic" than those emitted by other sources, even car exhaust, he stresses. They damage the health of people and wildlife living far from the fire itself because they are carried by the wind, but their poisonous effect is not sufficiently taken into account in air quality assessments, Labrador says. "Conventional risk models based on total PM2.5 concentrations may underestimate wildfire-attributable mortality by up to 93 per cent," the WMO says. One study cited in the WMO Bulletin says extreme fire-smoke events have tripled globally since the 1990s, contributing to nearly 100,000 additional deaths per year between 2010 and 2018, although this may be an underestimate. Ozone and microplastics worsen air pollution Another source of air pollution that carries major health risks is ground-level ozone, which accumulates when temperatures rise, atmospheric conditions stagnate and solar radiation is intense, as seen during recent heatwaves in China, Europe and the southeastern United States. "This increased exposure to ozone pollution has the potential to lead to tens of thousands of additional premature deaths," particularly due to respiratory diseases, the WMO warned. Another growing concern is aerosol particles, which can also travel to oceans and continents far from their source. They can alter the way the atmosphere reflects sunlight, change the chemical properties of land and water, and pollute otherwise clean environments. "One example is the deposition of black carbon – or soot – on snow and ice, which reduces the amount of sunlight reflected by these surfaces and in turn can hasten the melting process," the WMO explained. Another example is microplastics, formed when plastics break down because of sunlight or other factors, and found virtually everywhere – in the air, the soil and the oceans. One simulation in the WMO Bulletin estimates there are "51 million tonnes for land and 22 million tonnes for the ocean – which are in turn a source of microplastics for the atmosphere". "As plastic production and, critically, mismanaged plastic waste, continues to increase," monitoring the airborne paths that carry microplastics from their source and dump them in remote environments will be "crucial", the report said. Economic benefit of tackling climate change and air pollution together A separate report released on 7 September by the UN Environment Programme (UNEP) and the Climate and Clean Air Coalition (CCAC) highlighted the economic benefits of tackling climate change and air pollution as a joint problem. It found that every $1 (€0.86) invested in climate and clean air action can return $15 (€12.92). This is higher than tackling climate and clean air separately, and it includes both market and non-market economic gains, split across health systems, productivity and avoided climate damage. “For too long, we have treated climate action as a cost to be managed and air pollution as the unfortunate outcome of development," says Inger Andersen, Executive Director of UNEP. “This report shows the opposite: clean air is a key driver of development, health, food and energy security, and climate stability – an asset we must invest in.” Targeting emissions in six sectors – energy and fossil fuel systems, industry, transport, agriculture and food systems, residential cooking and heating, and waste management – the report lays out measures that, by 2050, could halve global carbon dioxide emissions and prevent 144 million air pollution related premature deaths. Renewable power, energy efficiency, electric vehicles, low-sulfur shipping fuels, more efficient fertiliser use, better wastewater management, and phasing down HFCs are among the 25 measures proposed.