Air pollution is a pervasive hazard affecting almost everyone on Earth. The World Health Organization reports that “almost all of the global population (99 %)” breathe air that exceeds WHO guideline limits on pollutants. Low‑ and middle‑income countries suffer the highest exposures. Pollutants come from sources like burning fossil fuels for transport and electricity, industrial processes, agriculture, waste incineration and residential cooking using biomass or kerosene. Air pollution has wide‑ranging health impacts. Fine particulate matter in ambient air contributes to strokes, heart disease, lung cancer and respiratory illnesses. The combined effects of outdoor and indoor air pollution are linked to around 7 million premature deaths each year. Household air pollution remains a major issue: about 2.1 billion people still use polluting open fires or simple stoves fuelled by wood, animal dung, crop waste or coal for cooking.
Air pollution and climate change are closely linked. Many of the drivers of air pollution—such as burning fossil fuels—are also sources of greenhouse‑gas emissions. Policies to reduce air pollution therefore offer “win‑win” benefits for both health and climate, lowering disease burdens while mitigating warming. Solutions include transitioning to cleaner energy sources, improving public transport, adopting energy‑efficient housing and industrial practices and promoting sustainable agriculture. For indoor pollution, cleaner cookstoves and access to electricity can reduce exposure. Urban planning that reduces traffic congestion and encourages walking and cycling also plays a role.
Because 99 % of people breathe unhealthy air, action must be global. Developed countries have made progress through legislation like the U.S. Clean Air Act, yet many cities still experience episodes of dangerous smog. In developing countries, rapid industrialization and urbanization outpace the enforcement of air‑quality standards. The WHO provides technical support to member states, develops guidelines and monitors global trends. Public awareness campaigns and community involvement are essential; people need to understand both the risks and the available solutions. Tackling air pollution is among the most cost‑effective public‑health interventions: cleaner air reduces healthcare costs, improves productivity and enhances quality of life. As the climate warms, reducing pollutants like black carbon and methane can also slow warming in the near term, buying time for deeper decarbonization efforts.