Published in The Lancet Public Health, the Children's Health in London and Luton (CHILL) study found that cleaner air following the introduction of the ULEZ was associated with improved lung growth in primary school children. The authors say this is the first study to demonstrate that improvements in air quality following the introduction of a clean air zone are associated with improved lung growth in children.
Led by researchers at Queen Mary University of London and the Nuffield Department of Primary Care Health Sciences, the study involved collaborators from Imperial College London, and the Universities of Bedfordshire, Cambridge, Edinburgh and Southern California.
The team followed more than 3,400 children aged 6–9 years from 84 primary schools between 2018 and 2022, studying children in central London and in Luton. Luton does not have a clean air zone and so it provided a reference group against which the London findings could be assessed. All the children were recruited before the ULEZ was introduced, allowing researchers to track changes in lung growth over time. Because researchers cannot assign children to breathe cleaner or dirtier air, the study was a natural experiment: it compared what happened in a city that introduced a clean air zone with what happened in one that did not.
Read the full story on the Nuffield Department of Primary Care Health Sciences website.