Sadiq Khan said the ultra-low emission zone is improving the lungs and lives of London children, after Queen Mary University of London published a new independent study on the policy. He said: "Critics said I was attacking motorists. It’s more important for me that the city’s children are no longer breathing dangerous levels of pollution".
The mayor said the scheme now has support from fresh evidence as well as from earlier research. He pointed to work from Imperial College London earlier this year showing that Ulez is already saving lives, while other research from King’s College London said that without additional action it would take almost two centuries to get nitrogen dioxide within legal limits.
Sadiq Khan and Ulez
Khan introduced London’s clean air zone more than seven years ago, beginning in central London after fierce opposition. He expanded Ulez to inner London in 2021 and then to the whole city in 2023, making it the biggest clean-air zone in the world.
He said: "When I introduced London’s clean air zone – the ultra-low emission zone (Ulez) – more than seven years ago, no city had ever attempted anything quite like it."
He also said: "The Ulez has already had an astonishing impact on London’s air."
Queen Mary University of London
The Queen Mary University of London study adds a child-health outcome to the policy record. The verified facts do not set out the measured size of the lung change, but they do link the finding to children in London who breathe traffic pollution, especially those near busy roads.
That connection fits the way young children are exposed. They breathe faster than adults, more often breathe through their mouths and are closer to vehicle exhausts because their heads are lower to the ground.
London air pollution
The policy’s wider record now runs alongside the child-health finding. Between 2019 and 2024, estimated deaths associated with air pollution in London fell by around 40%, and last year London said nitrogen dioxide levels had reached legal limits 184 years earlier than predicted.
For parents near busy roads, the new study strengthens the case that air-quality rules are not only about cleaner air in the abstract. It points to a direct health benefit for children already exposed to polluted streets, while leaving the size of that lung improvement unstated.
