What are super pollutants and how do they impact our health?

Carbon dioxide has long been the focus of climate action – but it’s not the only pollutant heating our planet. Other powerful pollutants are also driving climate change and harming our health.  

Super pollutants – so named because of their supercharged ability to trap heat – are responsible for nearly half of the warming we’ve experienced so far. And the air pollution that many of them contribute to leads to millions of premature deaths each year.

Unlike CO₂, which lingers in the atmosphere for centuries, many super pollutants are short-lived. That means reducing them can lead to immediate improvements in air quality and slow down global warming.

Super pollutants are powerful compounds that warm the planet much more than carbon dioxide.

Short-lived climate pollutants are a subset of super pollutants that only stay in the atmosphere for a matter of days, weeks or years. They include gases like methane and air pollutants like black carbon and tropospheric ozone.

Methane is the second most significant greenhouse gas after CO₂, with 86 times the warming power of CO₂ in its first 20 years in the atmosphere. It comes from both natural and human sources, with agriculture, fossil fuel extraction and waste making up most human-caused emissions. It stays in the atmosphere for around 12 years.

Black carbon, also known as soot, is an aerosol component of air pollution (PM2.5) that stays in the atmosphere for 12 days. It comes from things like car engines, wood stoves and wildfires. It makes air unhealthy to breathe and also makes the planet hotter by absorbing sunlight. It has a warming effect up to 1,500 times greater than carbon dioxide per tonne.

Tropospheric ozone, also known as ground level ozone, is a significant air pollutant and a major component of smog. It only lasts in the atmosphere for a few days to weeks. Ozone forms through chemical reactions between precursors like methane, volatile organic compounds and nitrogen oxides in sunlight – rather than being directly emitted.  

Hydrofluorocarbons (man-made gases used in refrigeration and air conditioning) and Nitrous Oxide (released from synthetic fertilizers and industrial processes) are also key super pollutants but have less of a direct impact on health.

Super pollutants aren’t just climate threats – but threats to our health.

Drive air pollution

6.7 million people die from air pollution every year. A large contributor to this is black carbon and tropospheric ozone – air pollutants that we breathe every day and have severe health impacts.

Black carbon is linked to serious health issues including heart and lung disease, strokes and asthma. Long-term exposure to the particulate matter in black carbon (PM2.5) is associated with 4 to 8 million deaths globally each year.  

Black carbon is also linked to high blood pressure and can negatively affect fetal development and birthweight during pregnancy.

Tropospheric ozone – of which methane is a major precursor – leads to 2.4 million premature deaths from heart and lung diseases. Exposure to tropospheric ozone can worsen asthma, bronchitis and other lung conditions, especially in children, the elderly, and those with pre-existing health issues.

Increase food insecurity

Methane emissions that contribute to ozone are estimated to cause up to 12% of annual losses in staple crop yields. Food insecurity linked to crop loss can worsen undernutrition, which is associated with nearly half of all deaths in children under five. Tropospheric ozone also damages plants by entering their leaves and harming tissue, affecting crops, grasslands, and forests. This damage to vegetation poses a growing risk to global food supplies. 

Black carbon reduces the amount of sunlight reaching Earth, altering rainfall patterns and accelerating melting when it settles on snow and ice. This contributes to crop failures.

Reducing super pollutants is one of the fastest ways to:

• slow global warming
• improve public health by reducing air pollution-related diseases
• protect food supplies by reducing crop damage and leaving rainfall patterns un-disrupted
• boost economies by lowering healthcare costs and increasing productivity 

We already have the tools to act. Here’s how we can reduce super pollutants and reap the benefits:

• Support strong policies: Advocate for regulations that cut greenhouse gas emissions and air pollution from agriculture, waste, transportation and industry.
• Invest in clean solutions: Promote renewable energy, electric vehicles and heat pumps that reduce both pollution and warming.
• Improve local air quality: Push for cleaner energy and industry, pedestrianisation and cycling, low emissions zones, greener public transport and better waste management.
• Raise awareness: Share the connection between air pollution and climate change to build public support for action.
• Back global efforts: Encourage your country to meet international agreements like the Global Methane Pledge and Kigali Amendment.
• Local leadership: Cities and communities can lead the way. Mexico City has shown that air quality regulations can reduce ozone and extend life expectancy. 

Super pollutants are powerful drivers of both climate change and air pollution – but they’re also one of our best opportunities for rapid progress. By cutting these emissions, we can clean the air, protect our health and cool the planet – faster than CO₂ measures and decarbonisation alone.  

At Wellcome, we’re championing bold, evidence-based action to cut super pollutants. We’re identifying the most effective solutions for both health and climate, supporting research to close knowledge gaps, and helping turn science into real-world change.

The solutions are within reach. Now is the time to act locally, nationally and globally to create a healthier, more resilient future for everyone.

• Short-lived climate pollutants and health – Climate & Clean Air Coalition
• How ‘super pollutants’ harm human health and worsen climate change – Carbon Brief