The Freedom of Information data recorded 213,341 paediatric hospital admissions and A&E attendances for respiratory conditions across responding NHS trusts, prompting calls for stronger action to tackle air pollution.
Children aged three and under accounted for more than half of the reported cases, with 120,000 babies and toddlers affected, according to the campaign group.
Children are particularly vulnerable to air pollution because their lungs are still developing and they breathe more air relative to their body size than adults. Exposure to pollutants including nitrogen dioxide and fine particulate matter is associated with respiratory illness and can worsen conditions such as asthma.
Manchester has seen a sharp rise in cases among its youngest children. Figures from Manchester University NHS Foundation Trust show admissions of babies and toddlers with breathing difficulties increased by 63.9%, from 654 in 2023 to 1,072 in 2025.
The increase follows the decision by Greater Manchester mayor Andy Burnham to scrap plans for a Clean Air Zone in 2023. The figures raise questions about progress in reducing pollution, although they do not establish that the decision caused the rise in hospital admissions.
Across the NHS trusts covered, at least 72,661 paediatric respiratory admissions were reported in 2025, alongside 140,680 A&E attendances where data was supplied.
Greater Manchester accounted for 20,863 cases across the trusts included in the dataset, while Birmingham recorded 19,627, Liverpool 12,066 and Sheffield 10,724.
Mums for Lungs said the figures highlighted the impact respiratory illness was having on children and the NHS, as well as the distress experienced by families whose children struggle to breathe.
The group is urging the Labour Government to reinstate its previously promised legal right to clean air through a Clean Air Act. The commitment was dropped from the party's 2024 general election manifesto.
Its calls include an enforceable pathway towards World Health Organization air quality guidelines, measures to reduce traffic pollution around schools, a transition away from diesel vehicles, action on non-essential domestic wood burning and a public health campaign explaining the risks of air pollution.
The campaign comes as Greater London, Glasgow and Bristol were identified by the Department for Environment, Food and Rural Affairs as having breached legal air pollution limits in 2025. London has continued to face concerns over unlawful pollution levels, years after the original compliance deadline.
Mums for Lungs said none of the cities covered by its research currently meets WHO air quality guidelines.
Jemima Hartshorn, Mums for Lungs, said: 'Behind every number is a child who is struggling to breathe and a family looking for help. We cannot keep treating dirty air as inevitable or acceptable - our children deserve cleaner air around schools, nurseries, their homes and busy roads, and we need action now. We need to restore funding to tackle air pollution in the Budget and Government to bring down pollution across the country. Let's be frank, non-essential wood burning and diesel vehicles have got to go. We all deserve to be healthy."
'London being declared to be illegally polluted again - failing to comply with limits that should have been met 15 years ago. This has to be a wake-up call for our Mayor to continue the work he started which has seen pollution levels fall. We need to ensure we can swap the most polluting diesel vehicles for cleaner options: cars, vans and buses. And Government needs to stand up to industry and ensure non-essential wood burning is phased out without any further delay.'
This article first appeared on Air Quality News.
