Only seven countries met World Health Organization (WHO) air quality standards last year, data showed on Tuesday, as researchers warned that the war on smog would only get harder after the United States shut down its global monitoring efforts.
Chad and Bangladesh were the world’s most polluted countries in 2024, with average smog levels more than 15 times higher than WHO guidelines, according to figures compiled by Swiss air quality monitoring firm IQAir.
Only Australia, New Zealand, the Bahamas, Barbados, Grenada, Estonia and Iceland made the grade, IQAir said.
Significant data gaps, especially in Asia and Africa, cloud the worldwide picture, and many developing countries have relied on air quality sensors mounted on U.S. embassy and consulate buildings to track their smog levels.
However, the State Department has recently ended the scheme, citing budget constraints, with more than 17 years of data removed last week from the U.S. government’s official air quality monitoring site, airnow.gov, opens new tab, including readings collected in Chad.
“Most countries have a few other data sources, but it’s going to impact Africa significantly, because oftentimes these are the only sources of publicly available real-time air quality monitoring data,” said Christi Chester-Schroeder, IQAir’s air quality science manager.
Data concerns meant Chad was excluded from IQAir’s 2023 list, but it was also ranked the most polluted country in 2022, plagued by Sahara dust as well as uncontrolled crop burning.