• Toxic air is responsible for millions of premature deaths each year.
  • Only one in ten people globally breathes air that conforms to WHO safe limits.
  • Transport emissions are linked to $1 Trillion in global health costs, annually.
  • Air quality projects amounted to less than 1% of all aid funding.

Particulate matter, nitrogen dioxide, ozone and sulphur dioxide...are some of the pollutants billions of us breathe in every day.

Toxic air contributes to conditions such as stroke, heart disease, chronic pulmonary diseases, lung cancer and acute respiratory infections. It also shapes the pace, extent, and regional distribution of climate change. To raise awareness of the dangers of air pollution, the United Nations has designated 7th September 2021 every year as the International Day of Clean Air for Blue Skies.

Now in its second year, the annual event aims to focus attention on the need for clean air with events in Nairobi, New York and Bangkok promoting this year’s “healthy air, healthy planet” theme.

Here are six things you need to know about the air you breathe:

1. Pollution causes thousands of premature deaths


Air pollution kills an estimated 7 million people worldwide each year. It causes an estimated one-quarter of all adult deaths from heart disease and stroke, 43% from lung disease and 29% from lung cancer, according to World Health Organization (WHO) figures. Transport emissions alone are linked to almost 400,000 deaths, according to the UN Environment Programme.

2. All people are exposed to pollution, but some are more exposed than others

Air pollution from industrial pollution, power generation, heating & cooling and transport impact both the developed and developing countries. Almost nine in every ten people are exposed each day to air quality levels that exceed WHO safe limits. Breathing polluted air impacts people in different ways and exacerbating existing inequities among different socioeconomic groups around the world.

The elderly, very young and those with pre-existing health conditions are more sensitive to the harmful impact of air pollutants, the European Environment Agency notes.

People of color in the United States are exposed to disproportionately high levels of ambient fine particulate air pollution (PM2.5) regardless of the emission source.
Income can also determine your exposure to polluted air. Deprived communities are more likely to be located near busy city roads or industrial areas, where pollution is greater. People in low- and middle-income countries are most exposed to toxic air, particularly in the bustling cities of Asia and other developing regions.

People in poorer parts of the world frequently have less access to quality healthcare and are at greater risk of exposure to the harmful effects.

Image: UNEP

3. Air quality spending is a drop in the ocean of funders’ budgets

The Clean Air Fund found between 2015 and 2020, official development funding on air quality projects amounted to less than 1% of all aid funding. The volume and pace of funding does not match the 153% rise in death rate due to air pollution in low- and middle-income countries in the last 30 years.

The research found that foundation funding on outdoor air quality projects increased by 17% to $44.7 million in 2020. However, according to the analysis, this amounts to less than 0.1% of grant making overall.

The bulk of this is from climate and environment foundations. Given the significant human impact of air pollution, there is an urgent need for health funders, alongside those with a focus on childhood development and equity, to invest in air quality.

Countries in Africa and Latin America, where air pollution is escalating, receive 5% and 10% respectively of development funding. Philanthropic funding is similarly concentrated outside of these continents.

4. Different pollutants cause different health issues


Here’s a quick guide to a few of the more common pollutants.

Particulate matter (PM) - tiny particles suspended in the air - are produced when solid and liquid fossil fuels are combusted in vehicles engines, for power generation and domestic heating. Overexposure to these particles can impact the body’s nervous and reproductive systems, and cause chronic heart disease and lung disorders, according to the EEA.

a diagram showing how a Air pollution causes a range of dangerous human health issues
Air pollution causes a range of dangerous human health issues.
Image: EEA

Sulphur dioxide (SO2) is emitted when fuels containing sulphur are burned. Volcanoes also emit SO2 into the atmosphere. These particles can cause headaches, anxiety and cardiovascular diseases.

Nitrogen dioxide (NO2) is formed when fossil fuels are combusted, mainly in car engines and power plants. These particles can cause breathing problems, asthma and reduced lung function, along with liver, spleen and blood conditions.

Ground-level ozone (O3) is formed by chemical reactions triggered by sunlight hitting pollutants emitted into the air from transport, natural gas extraction, landfills and household chemicals. They can cause cardiovascular problems, breathing disorders and other health problems.


5. Transport emissions account for $1 trillion annually in global health costs


Global transport emissions from on-road vehicles, agricultural machinery and construction equipment, are linked to $1,000,000,000,000 in health costs each year, according to UNEP figures. While transport-linked health impacts were falling
in the US, EU and Japan due to the imposition of stricter vehicle emissions standards, these reductions were being offset by higher impacts in unregulated nations like China, India and others high-volume vehicle markets, an ICCT study found.

In leading markets, electrifying buses and light duty fleet vehicles by 2030 will avoid an estimated 120,000 premature deaths from transport-related pollution.

Helen Clarkson, CEO of the Climate Group, said: “"Businesses, governments and public sector organisations have about half a billion light duty vehicles in their fleets around the world. By switching these vehicles to electric, these organisations can use their purchasing power to drive us to a better future.

"Not only can fleets electrify faster, but crucially it would help to bring about a wider shift to clean road transport by supercharging demand, boosting infrastructure and growing the used EV market, making them more readily available and affordable for consumers. As we head towards COP26, we need the right commitments, policy support and investment to make faster fleet electrification a reality."

6. Cleaning the air is an important form of climate action


Pollution and climate change are inextricably linked. Short-lived climate pollutants such as black carbon, methane, tropospheric ozone and hydrofluorocarbons are the most important contributors to the man-made global greenhouse effect after carbon dioxide. Reducing air pollution could avoid an estimated 0.6°C over the next few decades, slow the pace of Arctic warming by two-thirds, and reduce heat islands.

These pollutants have relatively short lifetimes in the atmosphere compared with carbon dioxide. Reducing emissions can translate relatively quickly into lower pollution concentrations and generate climate, health, and environmental benefits.

What’s the World Economic Forum doing about climate change?

Climate change poses an urgent threat demanding decisive action. Communities around the world are already experiencing increased climate impacts, from droughts to floods to rising seas. The World Economic Forum's Global Risks Report continues to rank these environmental threats at the top of the list.

To limit global temperature rise to well below 2°C and as close as possible to 1.5°C above pre-industrial levels, it is essential that businesses, policy-makers, and civil society advance comprehensive near- and long-term climate actions in line with the goals of the Paris Agreement on climate change.

The World Economic Forum's Climate Initiative supports the scaling and acceleration of global climate action through public and private-sector collaboration. The Initiative works across several workstreams to develop and implement inclusive and ambitious solutions.

This includes the Alliance of CEO Climate Leaders, a global network of business leaders from various industries developing cost-effective solutions to transitioning to a low-carbon, climate-resilient economy. CEOs use their position and influence with policy-makers and corporate partners to accelerate the transition and realize the economic benefits of delivering a safer climate.

Contact us to get involved.


As well as increasing the prevalence of extreme weather events like storms, floods, wildfires and droughts, climatic change also affects the frequency, duration, and intensity of infectious diseases. Mosquito-transmitted infections, viral diseases and water-borne infections are highly sensitive to changes in the climate, with warmer conditions reducing incubation periods and allowing infections to spread around the globe - assisted by increasingly mobile populations.

Image: UNEP