Air pollution as a global health risk: Emerging evidence, interventions and policy insights

Air pollution continues to be a major global health threat, causing around seven million early deaths each year and ranking as the fourth leading cause of illness and death worldwide. Fine particulate matter (PM₂.₅) and gaseous pollutants such as ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO) penetrate deeply into the respiratory and cardiovascular systems, causing oxidative stress, inflammation, and a range of chronic diseases. This burden disproportionately impacts low and middle-income countries, but high-income nations are not immune, with the United States reporting 100,000 to 200,000 air pollution-related deaths each year. Economically, air pollution results in trillions of dollars in healthcare costs and lost productivity worldwide. Recognizing the extent of this crisis, interventions have been developed at policy, technological, and household levels. Policies like the U.S. Clean Air Act and the EU Ambient Air Quality Directive have led to significant reductions in pollutant levels and related health burdens. Household interventions in low resource settings aim to cut indoor air pollution from traditional cooking methods, though their health benefits vary. Technological advances, including cleaner fuels and emission controls, show promise but require widespread adoption and cultural integration. This article assesses recent evidence on how air pollution affects biological mechanisms linked to disease, evaluates the effectiveness of interventions, and identifies critical gaps and future directions. Tackling air pollution demands coordinated global efforts that integrate health, environmental, and equity considerations to protect populations and achieve sustainable development goals.