Thousands of Londoners are still dying prematurely due to air pollution each year, but new research suggests the number of deaths linked to poor air quality has fallen significantly since the introduction of the Ultra Low Emission Zone (ULEZ).
Independent analysis carried out by experts at Imperial College London found that between 3,800 and 5,100 premature deaths in the capital were linked to air pollution in 2024. The study suggests that the mortality burden linked to pollution has fallen by around 40 per cent over the five years since ULEZ was introduced, driven by reductions in harmful pollutants such as PM2.5 and nitrogen dioxide (NO2), both of which are strongly linked to premature deaths.
While a reduction does not mean elimination, air pollution remains a major public health concern. However, the figures represent a substantial improvement compared with 2019, when researchers estimated that between 6,390 and 8,040 deaths were attributable to air pollution.
London Mayor Sadiq Khan said the findings provided strong evidence that ULEZ and other clean air policies have delivered measurable health benefits. “The bold action we have taken in London has reduced pollution, improved public health and saved lives,” he said.
“From dementia to childhood asthma, we know that 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.” Khan added that although progress had been made, further action was still needed to tackle air pollution across the city.
The report, published on 24 June, comes shortly after separate research linked the introduction of ULEZ to lower hospital admission rates.
Green Party London Assembly member Caroline Russell welcomed the findings and said the scheme had delivered cleaner air for millions of residents. “Just as we knew it would, the London wide ULEZ has delivered cleaner air across the capital, saving lives and improving the health of millions of Londoners,” she said.
However, she argued that more work was needed to address ongoing environmental challenges. “Too many Londoners are still breathing air that damages their lungs and increases the risk of serious disease,” Russell added.
The research found that the highest rates of air pollution related deaths per 100,000 residents in 2024 were recorded in outer London boroughs, including Bexley, Havering and Sutton.
The findings have sparked debate over the impact of ULEZ, particularly in areas where opposition politicians have criticised the scheme.
Conservative London Assembly member Thomas Turrell, who represents Bexley and Bromley, challenged the Mayor’s interpretation of the figures.
“Sadiq Khan is once again cherry picking what science he supports,” he said.”The truth is that air pollution was coming down naturally as Londoners upgraded to cleaner cars, not because of any government intervention.” Turrell also argued that improvements in air quality were part of a longer term trend rather than a direct result of the ULEZ expansion.
Despite the political disagreement, the latest figures indicate that air pollution continues to pose a significant health risk across London, even as overall levels of harmful emissions decline.
Article updated by Yashvi Jain
