Deaths linked to air pollution in London have fallen by around 40% between 2019 and 2024, according to new independent analysis by Imperial College London's Environmental Research Group.

The research, commissioned by the Mayor of London, estimates that pollution-related premature deaths dropped from around 6,400–8,000 in 2019 to approximately 3,800–5,100 in 2024.

The study also found nitrogen dioxide levels across London fell by 41% and fine particulate pollution by 28% over the same period.

Mayor Sadiq Khan attributed the improvements to sustained action on air quality, including the expansion of the Ultra Low Emission Zone (ULEZ) to cover the whole of London in August 2023 – making it the largest clean air zone of its kind in the world.

‘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 said.

‘From childhood asthma to dementia, 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.’

London met legal limits for nitrogen dioxide for the first time in 2024, almost 200 years earlier than experts had predicted without intervention. Despite the progress, air pollution is still estimated to cost London's economy up to £5.1bn annually.

Responses:

Rosamund Adoo-Kissi-Debrah CBE, a campaigner against pollution whose daughter Ella Adoo-Kissi-Debrah died following an asthma attack in 2013, commented: ‘The figures released today prove what I have known for a long time, that air pollution is killing people. We may not be able to see it, but the toxic air we are breathing every day is causing irreparable damage to every person who lives in London.’

‘The first steps of cleaning up the air in London with ULEZ have clearly been worth it to save people’s lives, literally saving thousands of people’s lives – a 40% reduction in lives lost,’ she added.

‘But there is still so much more to do to improve air quality in line with the World Health Organisation (WHO) guidelines, not just in London but for the rest of the UK too.’

Cecilia Vaca Jones, executive director, Breathe Cities, congratulated the mayor on the progress.

‘London’s journey is an inspiration and it is leadership like this that drives us at Breathe Cities,’ she said.

‘We see every day how the right policies, backed by data and community voices, can bring about change. London shows what is possible and we are taking those lessons around the world so that more babies, more children, more families, more communities can breathe cleaner air.’