The air we breathe: 97% of UK addresses breach at least one WHO limit for toxic pollutants

Shocking new data from Central Office Public Interest with the assistance of MapAid reveals the full extent of UK’s toxic air.

  • New Imperial College air pollution data calibrated to levels recorded at 20,000 monitoring sites in every major UK town and city is most accurate to date and publicly available today
  • Analysis by Central Office of Public Interest (COPI) and MapAid reveals 70% of UK addresses breach all three World Health Organisation limits, and 97% in breach of at least one WHO limit
  • New data freely available at so the public can see how polluted the air is where they live
  • COPI calling for air pollution disclosure to be mandated like asbestos and radon, with QC opinion report demonstrating strong legal case that estate agents are breaking the law by not doing so


Thursday 27 April, 2021: The full extent of the UK’s air pollution problem is revealed with the release of the most accurate and detailed pollution data yet, launched today via the national pollution checker


Analysis by the Central Office of Public Interest (COPI) with the assistance of MapAid reveals 21.5 million[1] (nearly 3 in 4) UK addresses breach the World Health Organisation limits of three  toxic pollutants. Shockingly almost all (97%) UK homes breach at least one WHO limit for toxic air.


To ensure data accuracy, COPI and MapAid sourced and mapped the air pollution levels recorded at 20,000 monitoring sites in over 320 UK council areas. Using this real-world and DEFRA-approved council monitor data, experts at Imperial College London could for the first time generate the 20m/sq resolution national model of this detail and accuracy.


Calibrated to the pollution levels recorded in every major town and city across the UK, the new data shows how big the problem is, revealing how urban areas fare worse than previously believed and the existence of pollution hotspots nationwide.


Along with providing pollution levels at a specific address, the website also gives every property in the UK a percentile ranking, making it easy to compare air pollution levels across the country. The heat map, above, shows how air quality varies across the UK. Buckingham Palace in central London falls into the 98th national percentile with some of the highest air pollution levels in the UK, and Balmoral Castle into the zero (lowest) percentile, with some of the cleanest air anyone can expect to breathe.


Cities understandably suffer greatest, but even addresses in the garden of England – Kent, as well as Bath, East Anglia and some coastal towns have some of the UK’s worst pollution. Some properties here fall into the top percentile for dirty air.


With the public release of this new data, COPI is pushing for clear legislation to publish air pollution ratings by estate agents, property websites, surveyors and conveyancers, similar to the obligations to disclose the presence of other dangerous substances, such as asbestos and radon. A  20-page legal opinion[2] from Jessica Simor QC and Neil Fawcett, commissioned by COPI, reveals a ‘strong legal argument’ that estate agents not doing so would be negligent.




Humphrey Milles (pron: Mills), founder of COPI and creator of the website, said: “Air pollution affects all of us. It’s a group one cause of cancer, just like asbestos. With this new accurate data now publicly available, it would be shameful for the property industry to not start acting transparently. Lives depend on it. Everyone has a right to know what they’re breathing before they buy or rent. And of course, we have our own part to play in this too. Air pollution isn’t insurmountable and we can all do something about it.




Rosamund Kissi-Debrah, whose nine-year-old daughter, Ella, died of air pollution in 2013 said ‘This data shows yet again that the government is failing the British public. Now people can really see the filthy air they’re breathing at their home, school or work address, and it is no wonder that the NHS waiting lists are ever growing. Everyone needs to know what they’re breathing, and now with this new public service they can.’


Professor Sir Stephen Holgate, special advisor on air quality to the Royal College of Physicians said, ‘Air pollution is an invisible killer, and because you can’t see it it’s easy for people to forget and ignore. It’s essential that the public are given air pollution data for where they are thinking of buying or renting. In many cases like that of little Ella, it can be a matter of life or death.’


The National Association of Estate Agents (NAEA) recently included air pollution into their PIQ (Property Information Questionnaire) which outlines the information that estate agents are urged to provide to potential buyers, and the property portal Search Smartly is set to become the first to display this new data on all its listings. Rightmove and Zoopla, both of which are not yet displaying air pollution data, declined to comment.


Commenting on the new data and legal findings, Rebecca Marsh of The Property Ombudsman (TPO) said “Air pollution is information all consumers should be aware of, before they make a decision on a specific property. Arguably, this is material information that all sellers or landlords should be providing to potential buyers or tenants.” provides annual average pollution levels for 2019 – the last year that was uninterrupted with lockdowns and travel restrictions. The data is 20m/sq resolution across the UK. The website shows the levels of three toxic pollutants – PM2.5, PM10 and NO2 – at any UK address. The data, from Imperial College London, is displayed in an easy to understand Air Quality Report (AQR). Every address is given a Low, Medium, Significant, High or Very High rating, depending on which national percentile ranking the property falls into. The health implications for living at the address are also provided in the AQR. These have been sourced from academic papers and vary depending on the specific pollution levels found at the address.


After checking the pollution levels at their address, visitors to are then encouraged to sign an online petition demanding that estate agents and property websites disclose air quality information to buyers and renters at the earliest opportunity.


The campaign is from the Central Office of Public Interest, a non-profit creative industry alliance. Funds to get the campaign established were originally raised from a successful Crowdfunder campaign in 2019, making this truly people-powered awareness campaign based simply on the best data available.


For further details contact:

The COPI press office: / +44 7811 328019

MapAid Chief Technologist /+33 768 751 750.


About  MapAid


Global MapAid, or simply “MapAid”, is a social enterprise and registered charity working with local people, to help them identify and map local solutions (hotspots) to benefit policymakers, agencies, and vulnerable people, as to where self-empowering aid is needed.


We take seriously the words of Nobel Peace Prize Winner and our Patron, the late Desmond Tutu: “We need to stop just pulling people out of the river. We need to go upstream and find out why they’re falling in”. Our goal at MapAid is to make maps that show where and why they are falling in, but also how to pull them out. We do this so the key stakeholders are able to see clearly where to apportion their finite resources:


Put simply: “We make maps that help direct aid.”


Our work is guided by the UN Sustainable Development Goals (SDGs) and broadly spans environmental or social projects across the world.