Today, more than half of the world’s population live in cities. By 2050, this proportion is expected to grow to two-thirds.
People live in cities to be close to employment and educational opportunities and services, and cities can be wonderful places for social interaction and access to cultural activities.
When cities are built using good planning principles, they can also be communities that foster health and wellbeing. Think of cities or neighborhoods you have particularly enjoyed living in or visiting – and how such places looked, felt or even “smelt”.
It is likely that these cities were full of people and life, with broad sidewalks and cycle lanes for easy, safe movement, an accessible public transport system and plenty of parks and green spaces, where people of all ages could exercise.
Unfortunately today, many rapidly growing cities are beset with heavy traffic, cramped slums and anonymous high-rise blocks that breed social alienation, noise and violence. All of these have a negative impact on our mental and physical health and our wellbeing.
One of the best overall “indicators” of a healthy or unhealthy city is air quality. This is because air pollution levels are typically low in well-planned cities with good transport systems, walkable streets and ample green spaces to filter the air. And air pollution levels soar in urban settings that prioritize road transport over pedestrians and cyclists, and that allow uncontrolled sprawl in large, grey, unbroken blocs of asphalt and concrete.
More than 80% of all cities worldwide exceed the air quality limits set by the World Health Organization (WHO). And more than half of all cities that monitor air pollution report air quality levels 3.5 times or more than the WHO limits.
Air pollution is an insidious killer. Every year 3 million people die prematurely due to outdoor air pollution, which is heaviest in major cities of Asia, Africa and Latin America. Most of these deaths are due to heart attack, stroke, respiratory diseases and lung cancers – that are also among the world’s top disease killers today.
When tiny, invisible particles of pollution penetrate deep into people’s lungs and bloodstream, these toxic pollutants accumulate in the body and eventually lead to cardiovascular disease and cancer.
WHO estimates that air pollution causes about 1 in 3 deaths from stroke, chronic respiratory disease and lung cancer as well as 1 in 4 deaths from heart attack. Ground-level ozone, produced from the interaction of many different pollutants in sunlight, is also a cause of asthma and chronic respiratory illnesses.
Air pollution is one of the most critical health threats we are facing today. Health and wellbeing MUST be the number one priority in urban planning. If we don’t take action now, air pollution will choke our cities and make them even more deadly places to live.
Since most sources of outdoor air pollution are beyond the control of individuals, we must call on our city mayors and other local leaders to push for change and commit to tackling air pollution head on.
Local and national governments need to introduce policies and make investments that support cleaner transport, energy-efficient housing, power generation, industry and better municipal waste management.
But we can also lead change at community and individual level. This can include commitments to cycle or take public transport to work, when safe routes are available; to recycle waste or compost; or conserve water and energy at home and in the office. Strategies such as “pedibus” initiatives can encourage children to walk to school safely, and the creation of urban gardens can provide both healthy foods and venues for social interaction and physical activity.
Many of these measures to improve environmental health also help people to be more physically active and eat a healthier diet, so reducing obesity and diseases like diabetes and heart disease.
We know that when cities take action to reduce air pollution, they can achieve dramatic progress. Almost half of all cities monitoring air pollution in high-income countries reduced air pollution levels by 5% between 2008 and 2013.
But we must move faster and with more urgency, particularly in low- and middle-income countries where progress on air pollution has not been so encouraging and the air quality is getting worse.
We need to ensure that people know about the levels of air pollution in their city and that they understand its deadly impact on their health. This is the most effective way to trigger action.
WHO has joined forces with United Nations Environment and the Climate & Clean Air Coalition on the BreatheLife campaign to give citizens access to this information and to mobilize cities to work together to achieve safe air quality levels by 2030. Almost 40 cities, including London, Oslo, Santiago, Seoul, Singapore and San Antonio, have joined BreatheLife and we are continuously expanding this network.
In October this year, WHO is hosting the first global conference on air pollution and health in Geneva. We will bring together government ministers, city mayors, health professionals, academics, activists and researchers to share knowledge and mobilize action for cleaner air and better health globally.
We all need to work together to make our cities healthier – and happier – places to live.