A third of the world’s population faced dangerously high levels of ozone pollution in 2026, with Asia hit hardest, according to a report from the EU’s Copernicus Atmosphere Monitoring Service (CAMS). The report, released on Wednesday, indicated that from January 1 to September 15, 34% of people globally experienced “extremely poor” air quality.
Ground-level ozone, which is harmful to health, forms when sunlight and heat react with pollutants from vehicles, industries, and wildfires. An “extremely poor” rating means ozone levels exceeded the World Health Organization’s guideline of 100 micrograms per cubic metre over eight hours. In contrast, only 5% of the population experienced “good” air quality during the period.
Record heatwaves and wildfires in Europe and North America contributed to this year’s pollution levels, with smoke from North American fires crossing the Atlantic and affecting air quality in Europe. “Air pollution does not stop at borders,” CAMS director Laurence Rouil warned, highlighting its ability to travel thousands of kilometres.
Asia had the highest exposure, with 53% of its population breathing “extremely poor” air. Major cities like New Delhi, Dhaka, Chongqing, and Lahore were particularly affected due to rapid industrialisation and agricultural practices. In North America, two-thirds of the population faced “poor” or “very poor” air quality, while 45% of Europeans were similarly affected.
In Europe, air pollution is responsible for approximately 60,000 premature deaths annually. Experts say it remains a significant health threat linked to diseases such as heart problems and respiratory illnesses.
In Africa, smoke from various sources, including crop burning and domestic cooking, led to 8% experiencing “extremely poor” air quality. However, 81% of South Americans enjoyed “good” or “fair” air, despite high ozone levels in cities like São Paulo and Rio de Janeiro. Oceania, including Australia and New Zealand, reported that 66% of its population experienced “good” ozone levels.

