Wildfires exacerbated by climate change played a major role in degrading global air quality last year, according to a new analysis.

The annual World Air Report published by the Swiss company IQAir claims wildfire smoke from Europe and Canada contributed to approximately 1,380 megatons of carbon being released across the world in 2025.

According to the study, Canada had its second-worst wildfire season on record last year, which affected air quality across Canada, the U.S and parts of Europe.

The report is based on data from monitoring stations across 9,446 cities in 143 countries, regions and territories.

The world’s 25 most polluted cities were all located in India, Pakistan and China, with India home to three of the four most polluted.

Regional Trends: North America, Europe And Asia

The most polluted major U.S. city was found to be El Paso, Texas, while South-East Los Angeles, California was the most polluted region.

The report says Europe saw mixed air pollution trends in 2025, with 23 countries........

© Forbes