Air pollution is described by the European Environment Agency as the biggest environmental risk in Europe. It’s a silent killer, but its effects are everywhere.
Air pollution is linked to an estimated 300,000 early deaths across Europe every year, and a staggering range of health problems including lung cancer, childhood cases of asthma, heart disease, Parkinson’s and dementia. Air pollution attacks every organ in the body and the effects last a whole lifetime. Children breathing polluted air today will see their future health impacted in 60-70 years from now, with the associated cost burden on every country’s health system.
So the question is not whether to act, but how. Air pollution comes from a variety of sources – from domestic wood burning (stoves and open fires), to construction, to industrial processes and incineration, to agriculture. Some of it is blown across borders and moved around as weather conditions change.
At Clean Cities Campaign (CCC), our principal focus is on tackling air pollution (and carbon dioxide) emissions which come from the tailpipe of vehicles. In 2019, road transport was the principal source of nitrogen oxides (NOX), responsible for 39% of emissions across Europe, most of that coming from older diesel vehicles. Nitrogen Dioxide (NO2) is one of the most dangerous pollutants and is associated with damage to the respiratory tract. Cars, buses and lorries are also responsible for creating particulate matter (PM). Of most concern is PM2.5, which is tiny particles of dust and metals which come from tyre wear and pollutants on the road surfaces. Particulate matter is so small it is more easily absorbed by the body and can cause short-term eye and lung irritation as well as long-term and more serious health impacts.

Cities lead the way
Our campaign is focused on cities – this is where most of us live and work, and cities are where many of the mobility solutions we advocate may be easiest to implement. Cities are places where a vision of the future can emerge, where leaders can redesign our public realm to be less dominated by motorised traffic.
One of our most popular campaigns is ‘School Streets’. This is where pedestrians and cyclists are prioritised on the roads around schools at drop-off and pick-up times, and car and vehicle access is restricted. The idea is catching on across Europe. School Streets are a fairly quick and easy to implement solution to tackle peak-time congestion, reducing the risk of traffic collisions involving cars and children walking to school, and helping to clean the air.
Another important pillar of our work covers what is known as “active travel” – promoting walking and cycling, instead of driving, as the best ways to get around our cities. Part of this involves redesigning our urban spaces to reallocate space away from cars and motor vehicles and towards people friendly cities – for example this could involve creating dedicated cycle lanes, enhancing parks and green space or reducing kerbside car parking spaces to create wider, safer pavements. And not forgetting the importance of public transport, which in many cities across Europe may be an unattractive option. Often vehicles or rolling stock are old and dilapidated, or services are expensive and unreliable. We are calling for cities to invest in public transport and create options for people living in “transport poverty” in poorly connected areas.
Why we back Low- and Zero-emission zones
As well as the obvious importance of making alternatives more available and accessible, and encouraging people to make the choice to change the way they move around our cities, we advocate for the development of Low- and zero-emission zones (LEZs and ZEZs) in our cities. These are traffic management schemes where access to the oldest and most polluting vehicles (usually diesel vehicles with engine standards older than Euro 5) is restricted. Most often the zones involve a charge on driving a polluting vehicle into the central zone of a city which should encourage people to make the switch to less polluting forms of transport. Perhaps the most famous example currently is London’s Ultra-low Emission Zone (ULEZ), which was first introduced in 2019 and should be expanded to cover the whole of London in August 2023.


Since the European Union agreed limits on exposure to air pollution (the Ambient Air Quality Directive AAQD), cities have been required to establish plans for how they will reduce air pollution. In many European countries, plans for LEZs form the backbone of attempts to tackle air pollution and the climate crisis, such as in Spain where 147 cities are legally obligated to introduce LEZs by 2023 (almost all Spanish cities have fallen behind on delivering this). Nevertheless, since 2019 there has been a 45% increase in the number of LEZ schemes across Europe – bringing the total to 325. There are also a number of zero-emission zones planned in European cities, including Amsterdam and Oxford. These would be zones where only electric vehicles would be permitted to circulate.
“a review of recent evidence found that on average LEZs delivered a 20% reduction on NO2 levels”
The body of evidence quite clearly shows that low-emission zones work and can drive quite striking changes in air pollution levels. The Clean Cities Campaign launched a review of recent evidence of the impact of LEZs in October 2022, which found that on average LEZs delivered a 20% reduction on NO2 levels. The effect was even more pronounced in London where, following the introduction of the ULEZ to the city’s central zone, NO2 recordings at the kerbside dropped by 44%. Some health experts claimed it was the most effective public health intervention on air pollution they had ever seen. In Madrid, the introduction of a low-emission zone led to a 32% drop in kerbside NO2 in 2019. LEZs have also made a difference to the amount of PM which was released from vehicles – a drop of 29% in PM10 levels has been recorded in Lisbon, and 10% in Madrid. CCC will be launching a more detailed analysis of these findings later this year.
How to make the changes fair
None of these changes to our cities are happening in a vacuum. As city leaders strive to implement policies to encourage residents to change their mobility habits, there is the concurrent challenge of the cost-of-living crisis. The CCC passionately believes that citizens must be supported with decent alternatives and financial help to switch to less polluting forms of transport. Our recent briefing ‘Win Win: 5 fast and fair solutions for cleaning up urban transport’ tackled that question head on and came up with a list of recommended measures city leaders and transport planners can employ to ensure clean transport policies do not hit low-income communities hardest.

Our top recommended solution for policy makers is mobility credits, which might take the form of a well-funded scrappage scheme, where drivers are offered cash to trade in their polluting vehicles. We know that these schemes work. A recent review of the £61m Mayor’s scrappage scheme which accompanied the extension of the London ULEZ to the north and south circular roads in 2021 concluded that 15,200 old polluting vehicles had been taken off the road. The scheme led to 140 tonnes of nitrogen oxides being removed from London’s air. Another successful scheme is the T-Verde card in Barcelona, where drivers are offered a free public transport pass for 3 years if they take their old car off the road.
“as city leaders strive to implement policies, there is the concurrent challenge of the cost-of-living crisis”
Our other top solutions include helping residents with the cost of buying a bicycle, improving public transport connections while also bringing the costs down. We also advocate for providing mobility hubs (For example electric scooter and electric bike hire) at local stations where onward public transport connections are less frequent. Our final recommendation examines a French scheme
to provide social leasing of small electric vehicles to those citizens who would find it hardest to afford the switch to a new car.
Not a zero-sum game
It’s important to also remember that there are significant costs attached to inaction on air pollution. This is a cost that every one of our societies across Europe bear every day. Research from the European Public Health Alliance (EPHA), quantifies the monetary value of premature death, medical treatment, lost working days and other health costs caused by three pollutants of most concern. The research shows that, at its worst, air pollution is costing every resident of Bucharest in Romania over €3,000 a year, and the country as a whole over €6bn. Five Italian cities including Milan feature in the top ten countries for associated costs of air pollution. Other cities are facing significant costs – Madrid is facing annual costs of over €3bn every year and Warsaw spends €4bn every year. The average European resident is paying over €1,200 every year.

At the same time, there is good evidence to show that it is often low-income households and communities of colour who are being disproportionately affected by the negative impacts of air pollution. We know that low-income families are more likely to live in built up areas and closer to busy main roads. Research by Friends of the Earth in 2022 found that over 90% of the most polluted neighbourhoods in the UK are in London, and that people of colour are three times more likely to live in these high pollution neighbourhoods, and that half of these neighbourhoods are among the most deprived in England.
We also know that in inner city areas, often a majority of residents don’t own a car (for example recent data from Lambeth in London revealed that nearly 60% of households don’t own a car). Often it is higher income families who are more likely to own multiple vehicles, including highly polluting diesel SUVs, and who are more likely to drive longer distances. There is also good evidence to suggest that many of the older cars owned by families tend to be petrol cars. In the case of the London ULEZ any petrol car registered after 2004 will be exempt from the charges – whereas diesel vehicles which are less than Euro 5 engine standard will be required to pay.


Moving forward to a clean future
Ultimately urban transport policy makers will need to strike a balance between the overall health benefits a clean transport policy will deliver and the problems that will come with the implementation of those policies. At CCC we believe that a zero-emissions future will not make us poorer, in fact there are multiple benefits in terms of freeing up urban space and positive life-long health impacts. What we imagine is a future where we are all free to move around cities without the burden of individual vehicle ownership, and that should apply especially to children and young people, and those with special mobility needs. Where challenges to this vision exist, we urge city leaders to prioritise inclusive and joined-up solutions which mean that everyone can benefit from the changes we so clearly need to see.