Air pollution, climate change, and lung health in Europe

Pollution, climate change, and sustainability was the official theme of the 2023 European Respiratory Society International Congress held in Milan on Sept 9–13. The topic is extremely timely following yet another summer in Europe where unprecedented heatwaves have repeatedly made front page news. Experts have called climate change the biggest global threat to humanity and associated temperature rises are intrinsically linked to air pollution, increased aero-allergen exposure, exacerbation of pre-existing lung diseases, and increased transmissibility of respiratory infections. WHO estimates that more than 90% of people globally breathe unhealthy air, mostly from the burning of fossil fuels; which translates into health and economic costs of US$8 billion per day. Ahead of the Congress, the ERS released a position statement in the European Respiratory Journal (ERJ) on Climate change and respiratory health proposing mitigation and adaptation strategies with consequent co-benefits on health, discussing how climate change affects clinical practice, and highlighting the importance of mobilisation of climate-friendly advocates for meaningful progress to be made. The latter is crucial given the ongoing debate in the European parliament on bringing the Ambient Air Quality Directive (AAQD) limits to be more in line with those set by WHO in 2021. In 2019, a European Green Deal was announced with the aim of Europe being the first climate-neutral continent by achieving net zero emissions by 2050. Key elements of the deal included: providing clean and affordable secure energy; preserving and restoring key ecosystems and biodiversity; fostering research; providing a fair and environmentally friendly food system; and adequate financing of any of these transitions. On Oct 26, 2022, as part of this Green Deal, the European Commission agreed to revise the AAQD which sets quality standards for 12 ambient air pollutants including PM2·5, so-called fine particulates. For PM2·5, the WHO 2021 air quality standard recommendation is 5 μg/m3. However, current European levels far exceed this concentration causing advocates to call for the EU to become more ambitious in the targets set to tackle the 300 000 premature deaths per year seen in Europe. A study in England also noted a 1·5% increase in the risk of hospitalisation for patients with COPD for every 1°C rise in temperature above 23·2°C. According to the position statement, the current EU standards are five times higher for PM2·5 and four times higher for NO2 than those set in the 2021 WHO Air Quality Guidelines. However, encouragingly, a vote in the European Parliament on Sept 13, 2023, favoured efforts to reduce AAQD thresholds, although the timeframe to achieve this change was pushed from 2030 to 2035 after strong political lobbying. Transportation is responsible for 20% of global carbon emissions. Experts in interviews from the ERS discussed several innovative European strategies that have been proposed to tackle this issue; such as a 15-minute city in Paris (where people are no more than 15 minutes' walk or cycle ride from work, school, or social events); superblocks in Barcelona which are car-free zones, and low emission zones for cars in the UK. Others called for improvements to address the inadequate monitoring of pollution levels and paucity of evidence in some Eastern European countries, and highlighted that some areas were returning to the use of older less clean fuels in face of the current energy crisis. Ultrafine particles also need to be monitored as these can affect other organs, in addition to their effects on the lung, and are found in placentas providing biological plausibility for the link between air pollution and low birthweight. The 2023 Air Quality Life Index report also indicated the need for better tools globally to generate high frequency local air quality data in light of the associated 2·3 years loss in life expectancy linked to poor air quality. Other continents, that are disproportionately affected by the intertwining effects of biodiversity loss, climate change, and air pollution, should also be involved in the setting of priorities. Low-income and middle-income countries have traditionally been lower polluters and received less financing to tackle the consequences of climate change than high-income countries; 62% of CO2 emissions since the industrial revolution have been contributed by North America and Europe, compared with only 3% from Africa. A global problem will need global solutions. Unite. Act. Deliver. is the strap line for COP28 which will be held in 2 months. Politics will likely be at the forefront of any discussions, but we all need to breathe, and clean air should be a human right. The 2023 ERS Congress was held in Milan on Sept 9–13.For more on the effects of climate change in Africa and the rest of the world see Comment Lancet Respir Med 2022; 10: 1115–17 The 2023 ERS Congress was held in Milan on Sept 9–13. For more on the effects of climate change in Africa and the rest of the world see Comment Lancet Respir Med 2022; 10: 1115–17