Air pollution remains one of the world’s deadliest public health threats, even though it often receives far less attention than more visible global crises.
Unlike a pandemic, famine or natural disaster, polluted air is not always easy to see. But its impact is severe. Millions of people around the world breathe unhealthy air every day, increasing their risk of heart disease, lung illness, cancer and other serious health problems.
The burden is often heaviest in lower-income communities, where residents may live closer to busy roads, industrial sites or areas with fewer environmental protections. But air pollution is not limited to one income level or one country. It is a global problem that affects cities large and small.
The encouraging lesson from London and New York is that air pollution can be reduced when city leaders use data, targeted policies and long-term planning.
TRENDING TODAY
In London, air quality experts once warned that without stronger action, it could take nearly 200 years for the city to meet legal roadside nitrogen dioxide limits. Instead, London reached that target in less than a decade after introducing stronger clean-air policies.
A major part of that progress came from better monitoring. Through the Breathe London program, air quality sensors were installed across the city in places where people live, study, work and receive care, including schools, hospitals and cultural sites. That local data helped officials understand where pollution was worst and where action was most needed.
But measuring pollution was only the first step. London also used the data to support policies such as the Ultra Low Emission Zone, known as ULEZ, and the introduction of more zero-emission buses. Those policies faced political opposition, but supporters say the results show measurable improvements in air quality and public health.
Recent research has also linked London’s clean-air measures to fewer hospital admissions for breathing and heart problems, strengthening the argument that air pollution policy is not only about the environment but also about healthcare.
New York has followed a similar path. By using air quality sensors and neighborhood-level data, city officials were able to target pollution sources more effectively. Supporters say that helped drive pollution down to levels not seen in decades.
The broader lesson is that cities do not always need to wait for national governments to act. Mayors and local officials can use their own powers over transportation, zoning, public transit and building rules to reduce harmful emissions.
That idea is now being expanded through Breathe Cities, a program launched by Bloomberg Philanthropies in partnership with the Clean Air Fund and C40 Cities. The initiative aims to help cities around the world gather better pollution data, turn that data into policy and share successful approaches with one another.
The program has already supported the deployment of nearly 1,200 air sensors across 14 participating cities, including new local monitoring networks in Accra and Nairobi. Several cities involved in the program have also committed to creating clean-air zones by 2030.
For local governments, the issue is increasingly being framed as a public health responsibility. Cleaner air can reduce pressure on hospitals, improve quality of life and make cities more attractive places to live and invest.
Still, clean-air policies can be politically difficult. Measures such as low-emission zones, vehicle restrictions and changes to public transport systems can face resistance from drivers, businesses and political opponents. That is why supporters argue that transparent data is important: it helps show where pollution is coming from and whether policies are working.
Air pollution may be invisible much of the time, but the solutions do not have to be. London and New York show that progress is possible when cities measure the problem clearly and act decisively.
Why It Matters
Air pollution is both a health crisis and a climate issue. Reducing toxic emissions can save lives, lower hospital admissions and improve daily life for people living in crowded urban areas. The examples of London and New York show that cities can make fast progress when they use data-driven policies instead of waiting for national governments to act.
What Comes Next
More cities are expected to expand local air monitoring and introduce clean-air policies in the coming years. If programs like Breathe Cities continue to grow, successful strategies from London, New York and other cities could become models for urban air pollution policies worldwide.
