Sir Sadiq Khan has credited the expansion of London's ultra low emission zone (Ulez) as "crucial" after a new study estimated that premature deaths linked to toxic air in the capital fell by approximately 40% over five years.
Ulez Expansion and Its Impact
The Mayor of London extended the Ulez across inner London in October 2021 and to cover the entire city in August 2023, creating the world's largest pollution charging zone. Vehicles that fail to meet minimum emissions standards and do not qualify for exemptions must pay a daily £12.50 fee to enter the zone.
A report by Imperial College London's environmental research group estimates that premature deaths attributable to air quality in London ranged from 3,800 to 5,100 in 2024, down from 6,400 to 8,000 in 2019. The study, commissioned by the Greater London Authority and Transport for London, used what its authors describe as "a scientifically stronger approach" compared to previous research, which had estimated 4,000 premature deaths linked to air pollution in 2019.
Reduction in Fine Particulate Pollution
Researchers also found that fine particulate pollution—extremely small particles that can seriously impact health—fell by 28% from 2019 to 2024. The report does not isolate the impact of the Ulez or any other single policy.
Boosting air quality has been a key priority for Sir Sadiq since he took office in 2016. In addition to introducing the Ulez in April 2019, other measures include a scrappage scheme for older, more polluting vehicles, providing air quality filters in schools, and increasing the number of electric buses.
Mayor's Statement
Sir Sadiq said: "The evidence is now overwhelming and unarguable: the bold action we have taken in London has reduced pollution, improved public health and saved lives. From childhood asthma to dementia, we know what a wide range of illnesses are linked to air pollution. This latest data shows why expanding Ulez London-wide was even more important than we previously thought and is transforming lives right across our capital. The decision to expand the Ulez was not an easy decision, but it's now proven beyond doubt that it was crucial to protect the health and lives of Londoners. However, I'm not complacent. Despite our incredible progress, there is still more to do."
Campaign Group Reaction
Jemima Hartshorn, founder of campaign group Mums for Lungs, said: "This research shows that big schemes like the Ulez really help clean up the air. And cleaner air means healthier Londoners. But every year thousands of Londoners die from air pollution. Londoners need more action, and so does the rest of the country."
