What the letter asks for

An inquiry into the unequal impacts of air pollution is the demand of 150 scientists, MPs and activists, including the climate activist Greta Thunberg, in a letter addressed to the prime minister, Andy Burnham.

The letter argues that the UK does not have a dedicated mechanism to address the health inequalities caused by dirty air, and that the leading threat to clean air comes from traffic emissions from petrol and diesel vehicles, with wood-burning stoves and industrial fossil fuel burning among other sources.

The evidence of unequal exposure

Institute for Fiscal Studies research shows lower-income areas have persistently higher levels of air pollution than wealthier areas across England, and minority-ethnic populations were exposed to levels about 6% higher than white populations.

Long-term exposure is linked to heart disease, strokes, cancer, asthma and effects on lung development in children.

Children are particularly vulnerable because:

• their lungs are still developing
• they breathe more air relative to their body size than adults

Children admitted to hospital

Freedom of information data gathered by Mums for Lungs shows more than 200,000 children were taken to hospital with breathing difficulties in 2025 across 11 English cities and areas including London, Greater Manchester and Birmingham. More than 120,000 of those admitted to A&E or hospital were babies and toddlers, with younger children the most affected.

In Manchester, admissions of babies and toddlers rose from 653 in 2023 to 1,072 in 2025. The group said Burnham's 2023 decision, as Greater Manchester mayor, to scrap plans for a clean air zone raised questions about whether sufficient action was being taken.

Jemima Hartshorn, founder of Mums for Lungs, called the situation an "air pollution emergency" and 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."

Government and campaigners respond

Rosamund Adoo-Kissi-Debrah, whose nine-year-old daughter was the first person in the UK to have air pollution cited on their death certificate, blamed political inaction. She said a "failure of inaction by all the main political parties over so many years, has meant the UK population is exposed to illegal levels of emissions".

The letter points to London's ultra-low emission zone as evidence that policy can work: children's lungs were found to have grown bigger and stronger as a result of the policy. Yet new government data shows parts of London, Glasgow and Bristol still had illegal levels of air pollution in 2025.

A Defra spokesperson said: "Air quality continues to improve over the longer term and while most air quality standards are being met, more action is needed to protect communities." Adding: "Our ambitious new targets will cut harmful particle exposure by nearly a third by 2030." The department said it is working with local authorities through clean air plans and monitoring.

The letter demanding an inquiry into air pollution health inequalities is now with the prime minister, Andy Burnham, while Defra points to its 2030 target for cutting harmful particle exposure.