Air quality has improved in Europe but exposure remains high

Expert warns that “easy gains” have been made but further progress against more diffuse sources such as non-exhaust traffic particles could be challenging and expensive

Air pollution levels have improved in Europe over the past 20 years, according to a study led by the Barcelona Institute for Global Health (ISGlobal), which looked at pollution levels in more than 1,400 regions across 35 European countries.

However, almost all Europeans (98%) live in areas that the World Health Organisation (WHO) says have unhealthy levels of small particles known as PM2.5. The figure is 80% for larger particles (PM10) and 86% for nitrogen dioxide.

The research team also reported that 86% of Europeans experienced at least one day with ‘compound air pollution events’ each year between 2012 and 2019, where multiple pollutants exceeded WHO limits simultaneously.

In addition, the researchers noted the ‘complex interplay’ between PM2.5 and ozone (O₃), a gas which is damaging to human health, chiefly respiratory inflammation. They said that warmer temperatures and stronger sunlight in summer boost O₃ formation through chemical reactions, which is worsened by the increasing likelihood of wildfires.

Zhao-Yue Chen, ISGlobal Researcher and lead author said: "Targeted efforts are needed to address PM2.5 and O₃ levels and associated compound unclean days [when limits for two or more pollutants are exceeded simultaneously], especially in the context of rapidly increasing threats from climate change in Europe.

“The EU is seeking a way to bring EU air quality standards in line with WHO recommendations, which would be good news for public health,” he said.

Joan Ballester Claramunt, ISGlobal Researcher and senior author of the study said that conventional air-pollution control strategies, which focus on reducing primary pollutant emissions, may not be enough to effectively mitigate excessive O₃ and associated compound unclean days.

He said: “Addressing climate change, which influences ozone formation through increased sunlight and rising temperatures, is crucial for long-term ozone management and protection of public health.” 

However, Professor Roy Harrison at the School of Geography, Earth and Environmental Sciences at the University of Birmingham warned that the “easy gains” have been made through vehicle exhaust catalysts and diesel particle filters.

He said: “Further progress against more diffuse sources such as woodsmoke, cooking emissions and non-exhaust traffic particles is both technically challenging and potentially expensive.”

In terms of the health impacts, Tim Dexter, Clean Air Lead at Asthma + Lung UK said: “[Air pollution] contributes to up to 43,000 premature deaths a year across the UK. Toxic air can worsen and trigger symptoms including wheezing, breathlessness and sometimes leads to life-threatening asthma attacks. Children are particularly vulnerable as harmful air pollutants can stunt lung growth.”

He added that much more needs to be done by the government to improve the availability of “cleaner, healthier modes of transport.”

“The current focus on reporting is overly concerned with average PM levels by mass and not nearly enough on exposure and nanoparticles.”

A different perspective came from Tim Smedley, author of Clearing the Air, who warned: “The current focus on reporting is overly concerned with average PM levels by mass and not nearly enough on exposure and nanoparticles. Air-pollution risk comes down entirely to exposure. The peak pollution episodes on our streets can vary massively minute by minute and are known to be consistently worse in poorer neighbourhoods.

“A shift of focus would concentrate policy on hyper-local actions, such as closing the roads outside schools to cars during drop-off and pick-up times (as is starting to happen in Edinburgh, Hackney and Islington).

“It would also shift local authorities away from measuring pollution with a handful of fixed, blunt-instrument air pollution sensors such as diffusion tubes or modelling.”

Image credit: Shutterstock