A campaign for cleaner air in cities
It’s in the Air is C40’s global public awareness and engagement campaign on urban air quality. It brings together mayors, athletes, doctors, and communities to build public support for clean air zones and show what healthier cities look like.
Working alongside C40’s policy programmes, the campaign helps:
- shape public opinion
- counter misinformation
- make the case for clean air action in a clear, relatable way
- celebrate cities taking bold action for cleaner air
Why air quality needs public attention
No amount of air pollution is safe for human health.
Breathing clean air is a fundamental human right. Yet, 99% of the world’s population lives in areas with dangerous air quality.
Air pollution is a global public health emergency that affects every part of our body, increasing the risk of serious conditions from heart and lung disease to dementia and mental health issues.
Toxic air affects us all, but not equally. The World Health Organization (WHO) estimates that 6.7 million people die prematurely from air pollution every year. 91% of these deaths occur in low- and middle-income countries, with children, older people, and vulnerable communities disproportionately impacted.
UNICEF warned that dangerous levels of air pollution contribute to 600,000 child deaths annually.
Cities are taking bold actions against air pollution
Cities are already making major progress on cleaning the air. The It’s in the Air campaign helps make this work more visible, supports public understanding of why these policies matter, and strengthens the momentum needed to deliver them at scale.
Over 30 C40 cities have signed up to the Green & Healthy Streets Accelerator to transform streets and public spaces by 2030. Through actions like electrifying public transport, creating low- or zero- emission zones, and expanding walking and cycling infrastructure, they’re making bold changes for cleaner air.
More than half of all C40 cities have committed to taking action through the Clean Air Accelerator. They are addressing air pollution across sectors such as waste management, building energy efficiency, and freight transport, while improving air quality monitoring. These actions aim to deliver cleaner air and better health for an estimated 252 million people. Air quality is improving across C40 cities. Today, 99% of them meet at least one air quality guideline set by the World Health Organization for nitrogen dioxide (NO₂). As of 2023, a quarter of cities had fine particle (PM2.5) levels lower than the World Health Organization’s first target, below 10 micrograms per cubic metre.
Hope is in the air: a global movement for clean air zones
It’s in the Air: 2024 global marathon
In 2024, cities around the world – including frontrunners Bogotá, Johannesburg, London, Paris, Quito, Seattle, and Stockholm – participated in a global marathon that highlighted the importance of clean air zones, one of the most impactful transport policies for cutting emissions and transforming how we move around our cities.
The campaign ran for eight weeks, starting during the Summer Olympic Games in Paris until International Day of Clean Air for Blue Skies. Cities were joined by various key stakeholders, including partners and youth leaders, to celebrate the important work being done to transform streets and public transport, improve air quality, and people’s health.
More than 10,000 city residents across four regions took part in on-the-ground community activities, air quality workshops, and #ItsInTheAir creative events during the marathon. The campaign reached millions online through multimedia content that amplified the campaign’s vision, showcased on-the-ground activities, highlighted local community stories, provided useful information, and tackled common myths about sustainable transport and clean air zones.
It’s in the Air x Breathe Cities
In 2025, It’s in the Air partnered with Breathe Cities to grow the marathon and launch a cultural campaign that connects clean air, sports, and health, sparking local and global momentum for urban clean air action.
Breathe Cities is a pioneering initiative aiming to cut air pollution by 30% (from 2019 levels) by 2030 across 14 major cities, making the air safer to breathe for millions. By boosting advocacy, strengthening policies, and supporting mayors to deliver bold solutions, Breathe Cities is setting new global standards for air quality action.
From the World Health Organization (WHO) Air Pollution & Health Conference in March 2025, to community events in Bangkok, Johannesburg, and Rio, and a major global moment this November, the campaign is bringing together a powerful group of voices,
Mayors, athletes, doctors, footballers, scientists, activists, and more are coming together to demand cleaner air, fight misinformation, and show what real change looks like in cities around the world.
How-to guide
Everyone has a role to play.
C40’s Clean Air Toolbox is a practical guide to help cities design clean air zones, engage communities, and build public and political support. It includes expert advice, global case studies, and best practices for city staff, campaigners, and civil society.
Download it now in English, French, Portuguese, or Spanish.
Related
Cities worldwide are proving that climate action is most successful when equity and fairness are at the heart of every decision.
Cities are urgently working to clean the air to protect communities from pollution that causes 6.7 million premature deaths globally each year.
Commitments by C40 cities to drive ambitious climate results and halve fossil fuel use by 2030.
