Each of us breathes an average of 12 to 20 times a minute. The air that keeps us alive also poisons us when it is polluted. This constant exposure is no trivial matter. Air pollution is undoubtedly one of the greatest environmental risks of our time.
Air pollution, broadly defined as the presence of harmful substances in the air, takes many forms, including smog, acid rain and particulate pollution. Its sources range from industry and transport to energy generation and waste.
According to the World Health Organization (WHO), more than 90% of the global population breathes polluted air that fails to meet the limits in the WHO air-quality guidelines. The combined effects of outdoor and household air pollution cause close to seven million premature deaths each year.
Heart disease and stroke are the leading causes of premature death associated with air pollution, followed by chronic lung disease, acute respiratory infections and lung cancer. People in low- and middle-income countries bear a disproportionate share of outdoor air pollution, and 89% of premature deaths occur in these countries.
One of the most common indicators of air pollution is particulate matter, consisting of components such as sulphates, nitrates, ammonia, sodium chloride and black carbon.
Other major pollutants include carbon monoxide, particularly from fuels such as oil, coal and natural gas; ozone, formed when gases react in sunlight; nitrogen dioxide released into the atmosphere by fuels used in transport and industry; and sulphur dioxide from fossil fuels.
Fossil Fuels Are the Principal Cause
Although the sources of air pollution and the solutions are well known, global progress is far too slow. One of the main reasons is that pollution is viewed in isolation. We need a reciprocal perspective that treats air pollution and climate change as mutually reinforcing problems with many of the same causes.
Transport, the energy sector, industrial emissions, agricultural activity and household heating all drive both climate change and air pollution. Today, 85% of air pollution results from burning fossil fuels and biomass.
While greenhouse gases such as carbon dioxide and methane trap heat in the atmosphere, air pollution reduces the soil's capacity to store carbon, intensifying climate change. As climate change increases the frequency and severity of extreme events such as wildfires, air quality can deteriorate further. Longer, hotter summers, more wildfires and drought, for example, increase ground-level ozone and particulate pollution.
Half of global warming is attributable to super-pollutants including methane, black carbon and ground-level ozone. Hydrofluorocarbons used in refrigeration and air-conditioning systems, for example, are powerful greenhouse gases with a warming effect thousands of times stronger than carbon dioxide.
Sulphur dioxide, meanwhile, can form reflective aerosols that cool the planet in the short term, but it also causes acid rain, damages ecosystems and forests, and thereby weakens an immense carbon-storage system.
Air Pollution Cannot Be Separated from Climate Change
Most action to improve air quality also helps combat climate change. Many drivers of climate change involve inefficient and polluting energy and transport systems, so strategies for tackling climate change and air pollution complement one another.
Reducing or ending the burning of fossil fuels and biomass can lower both greenhouse gas emissions and air pollutants harmful to health. By addressing environmental sustainability together with public-health protection, we can make major progress in combating climate change and achieving the Sustainable Development Goals.
Burning fossil fuels for electricity generation, transport and industry contributes to air pollution, and scientists agree that a warming climate will further worsen air quality.
It is therefore important to begin from the understanding that air pollution is preventable. The laws, standards, policies, programmes, investments and technologies that provide solutions are known. Implementing them requires substantial investment, but the benefits are incomparable with the costs.
Policies and investment that support clean transport, energy-efficient homes, cleaner electricity generation and industry, and better municipal waste management can reduce the main sources of outdoor air pollution. Access to clean household energy can also significantly reduce outdoor air pollution in some regions.
A Social Issue as Well as an Environmental One
Although the connection between climate change and air pollution receives increasing attention, another important perspective is to treat clean air as a human right. This approach does not regard air pollution and climate change merely as environmental problems. Air pollution is clearly a social issue involving social justice, health, equality and states' obligations.
United Nations Special Rapporteur on the human right to a clean, healthy and sustainable environment Astrid Puentes Riaño recently presented a new report to the UN Human Rights Council in Geneva, calling on governments, companies and international NGOs to treat air pollution as a human rights crisis.
The report emphasises that children, women, older people, pregnant people, outdoor workers and people with pre-existing health conditions are exposed to disproportionately high levels of air pollution. It also recalls that, under international human rights law, states are obliged to prevent foreseeable harm, regulate polluting activities and protect those most at risk.
The study also addresses the private sector, calling on companies to conduct human rights and environmental due diligence, protect employee health and reduce emissions in line with scientific criteria rather than merely meeting minimum legal requirements. Its recommendations to governments include integrating air-quality planning with human rights and climate frameworks, identifying pollution hotspots and prioritising vulnerable communities.
According to the report, one of the most critical steps is to close coal-fired power plants. It also calls for air-quality monitoring, identification of the principal sources of air pollution, public information and participation, and the introduction of laws, regulations and standards to limit pollution. Countries should develop national air-quality action plans.
At the same time, courts in different parts of the world are issuing important judgments on air pollution and climate change. These decisions recognise the right to a clean, healthy and sustainable environment as a universal norm and strengthen the response to these challenges. Yet despite recent legal progress, significant gaps remain. Restorative climate justice is essential for our planet's ecosystems and the people within them.
Aligning human rights law with climate justice is therefore a priority. As we strengthen accountable justice and turn this body of law into an enforceable and binding instrument, our efforts to combat air pollution and climate change will accelerate further.
13 May 2026
