An estimated 40% fewer deaths are now linked to air pollution in London compared to 2019, according to a recent analysis by Imperial College London. This significant reduction comes alongside a sharp decrease in the capital's toxic air, with nitrogen dioxide levels falling by 41% and fine particulate pollution by 28% over the same five-year period.
However, the study, conducted by Imperial's Environmental Research Group, led by Dr. David Dajnak, also presents a more sobering picture regarding the overall health impact of air pollution. Updated scientific understanding indicates that the adverse effects on health are more profound than previously believed. While earlier estimates attributed around 4,000 premature deaths in 2019 to air pollution, this figure has now been revised upwards to an estimated 6,400-8,000 for that year. The latest projections for 2024 suggest a range of 3,800-5,100 premature deaths.
Dr. Dajnak commented on the findings, stating, “Our study highlights two key findings: London’s air quality has improved markedly since 2019, but despite this progress, air pollution remains a serious public health risk.” Recent evidence has shown stronger links between air pollution and conditions such as cardiovascular diseases, dementia, and diabetes, in addition to known respiratory illnesses.
The research identified that outer London boroughs, including Bexley, Havering, and Sutton, now have the highest ratio of deaths attributable to air pollution in 2024. This finding, according to City Hall, underscores the importance of the Ultra Low Emission Zone (ULEZ) expansion across the entire capital in 2023, a move that faced considerable local opposition.
Mayor of London, Sadiq Khan, welcomed the report, asserting that it provides “overwhelming evidence” that policies such as the ULEZ are saving lives. Although the independent Imperial College report does not specifically credit the ULEZ or any other single policy, Khan stated, “The evidence is now overwhelming and unarguable: the bold action we have taken in London has reduced pollution, improved public health and saved lives.” He further added that the latest data demonstrates why the London-wide expansion of ULEZ was even more crucial than initially thought, transforming lives across the capital. The ULEZ, first introduced in central London in 2019 and expanded to inner boroughs in 2021, charges non-compliant vehicles, typically older diesel or petrol models, a daily fee of £12.50. Approximately 97% of vehicles in the zone are now compliant.
Professor Stephen Holgate, special adviser on air quality at the Royal College of Physicians, praised the scale of improvement as “so encouraging” and a “powerful reminder that decisive, sustained action can deliver real, measurable benefits for people’s health.” While acknowledging the progress, Jemima Hartshorn of Mums for Lungs highlighted that over 100,000 children were hospitalised with breathing issues in London in 2024, and other UK cities and regions still face higher pollution levels, advocating for continued action across the country. The Imperial College London study is peer-reviewed and builds upon existing research into the health impacts of air pollution.