Ditch Diesel
Image: Crispin Hughes
Click the image to jump to information on the 2025 class action
Our diesel campaign calls for commitments from all levels of government to phase out diesel by 2030, to protect the next generation from its devastating health impacts.
Air pollution poses the greatest environmental threat to public health in the UK. Exposure to air pollutants, such as nitrogen dioxide and particulate matter, can shorten life expectancy and is linked to various negative health effects, including respiratory and cardiovascular diseases.
It is estimated that, on average in the UK in 2023, 68 per cent of the nitrogen dioxide (NO2) concentrations at the roadside originated as nitrogen oxide (NOx) emissions from road transport.
Diesel vehicles are the single biggest contributor to the NOx and NO2 on our roads, as shown here in Professor Chris Whitty’s Air Pollution Report (Figure 6, Page 8).
Health effects
Diesel vehicles emit NOx and NO2, which inflame lungs and are closely linked to childhood asthma and wheezing. Children are developing lifelong, chronic conditions, including poorly developed lungs, asthma, high blood pressure, inattention and hyperactivity, and mental illness as a result of exposure to air pollution.
Short-term effects of exposure to NO2 include inflammation of the lungs and airways, and long-term exposure can affect lung function and breathing and worsen asthma.
Dieselgate
Did you know there are an estimated 2.5 million diesel cars on the road in the UK emitting suspiciously high levels of air pollution?
After the 2015 Dieselgate scandal, when it was discovered that emissions defeat devices had been installed in Volkswagen’s cars, Government agencies across Europe began to test real-world emissions. The results of these revealed that diesel cars across manufacturers emit high levels of nitrogen oxides (NOx) during real-world operation.
Real-world diesel emissions
The International Council on Clean Transportation’s (ICCT) 2017 white paper showed that while some Euro 6 diesel cars, (those that are allowed within London’s Ultra Low Emission Zone), were found to emit less NOx than the legal limit of 80 mg/km, others exceeded this by a factor of 12.
“Only 10% of tested Euro 6 vehicles would meet the Euro 6 limits on the road.”
The Real Urban Emissions (TRUE) Initiative collects and publishes real-world data on NOx emissions from in-use vehicles via remote sensing. The study they carried out in London from 2017 to 2018 revealed that NOx emissions from diesel cars in London are, on average per kilometer, 6 times those of petrol cars.
TRUE’s ratings show that nearly all diesel vehicles on European roads received a “poor” rating.
Image taken from this TRUE factsheet.
The legacy of Dieselgate
A 2023 reassessment of excess NOx in diesel cars in Europe, following the Court of Justice of the European Union clarification of the definition of a defeat device, revealed that “suspicious” levels of NOx emissions were found in 77 per cent to 100 per cent of tests and vehicle averages, indicating the likely use of a prohibited defeat device, and led to Client Earth’s announcement that it was sending legal complaints to three national governments, including the UK Government, to demand they address the legacy of Dieselgate.
2025 class action
In 2024 the Department for Transport began investigating prohibited defeat devices in dozens of diesel vehicle models. Several law firms have subsequently jointly launched the biggest group claim ever to come before any of the UK courts, representing more than 1.2 million vehicle owners. Yet the details of the case have been deemed confidential due to the commercial interests of the defendants, the car manufacturers. We believe there should be full transparency about the vehicle emissions we are all breathing.
Mums for Lungs has written an open letter to the judge in the case, calling for documents related to the litigation to be made publicly available due to the significant public interest in this matter. The letter has been signed by over 500 individuals and 40 organisations and will be handed to the court by Mums for Lungs representatives in late February.
Mums for Lungs are calling for all affected cars to be immediately recalled by the manufacturers, and for a major UK fund worth at least £1 billion to be put together, in order to pay for measures to alleviate the impact of the air pollution car manufacturers are responsible for.
How to ditch diesel
Local authorities can fast-track the phase-out of diesel vehicles at the local level by:
• Phasing out new residential parking permits for diesel cars
• Introducing emissions-based parking tariffs
• Creating zero-emission loading bays and taxi ranks
• Setting a vision and publicly committing to a diesel-free borough by 2030
We know that it will take longer to transition away from diesel vans, which is why the 2030 deadline needs to be set now. The UK Government needs to support industry to bring cleaner alternatives to market – current offerings are limited and expensive.
Levels of nitrogen dioxide in London
Annual roadside NO2 concentrations in London dropped by nearly half (49 per cent) between 2016 and 2023, due to measures such as London’s Low Emission Zone, the Ultra Low Emission Zone and the introduction of cleaner buses. Despite this progress, the latest London-wide monitoring data shows that there is a long way to go until Londoners are breathing clean air.
The map below displays recorded levels of NO2 across London in 2022, which is the latest annual data available. Anything yellow, orange or red shows levels above World Health Organization (WHO) guidelines. As you can see, almost all Londoners are breathing air that is over the guidelines, some by nearly five times.
Click on a coloured dot to find out more about the air at each monitoring station.
Taking action
Consumers have already started taking action; yet there are still over 400,000 diesel vehicles on London’s roads alone. We need to remove diesel cars, even the newest models, from our roads. We want to see commitments from all levels of government to phase out diesel by 2030, to protect the next generation from its devastating health impacts.