London’s ULEZ linked to healthier lungs in children

London’s ultra-low emission zone tackles dirty air by charging drivers of polluting vehicles. The policy has produced political fireworks, but new research asks a human question: did children’s lungs improve after cleaner vehicles became the norm?

Researchers followed around 3,400 schoolchildren in London and Luton before and after the central London ULEZ began. Beforehand, London children had significantly smaller lungs. Five years later, their lung size and function were comparable with children in Luton. The share with impaired lung function fell from 14% to 9% in London, against 9% to 7% in Luton.

Lungs grow rapidly during childhood, and lost growth can shape health for decades. The findings suggest traffic rules can deliver more than cleaner charts: reducing exposure may give developing lungs room to catch up. Charging to use London's roads has, unexpectedly, become a children’s health intervention.

The study cannot prove ULEZ alone caused every improvement, and it examined the earlier central zone rather than every stage of London’s expansion. Air pollution in London, Luton and other UK cities remains above recommended levels. Easier breathing is progress, not permission to stop working for cleaner air.