A new IQAir report reveals nearly all of the world’s top 20 most polluted cities in 2023 were in Asia. India alone accounted for 13 cities, including Byrnihat—the worst-affected with PM2.5 levels 25 times above WHO guidelines—and Delhi, which remained the globe’s most polluted capital for six straight years. Pakistan had four entries, while China and Kazakhstan each listed one city. The only non-Asian city was Chad’s N’Djamena.
PM2.5 particles, tiny enough to enter lungs and bloodstreams, pose severe health risks. WHO recommends annual exposure below 5 µg/m³; Byrnihat recorded 128.2 µg/m³. Despite China reducing emissions, coal expansion plans threaten progress. Meanwhile, Iran and Afghanistan lacked data, and Southeast Asia faces monitoring gaps, exacerbated by the U.S. halting embassy air quality sharing.
North America’s worst pollution was in California cities like Ontario and Huntington Park. Though the U.S. reduced PM2.5 levels by 22% since 2023, only 17% of global cities met WHO standards. IQAir urges governments to boost renewable energy funding and tighten emissions rules to combat air pollution. Locals like Byrnihat resident Suman stress the urgency: “We want authorities to act before our city tops this list again.”
Source: https://edition.cnn.com/2025/03/11/india/air-pollution-global-ranking-asia-india-intl-hnk/index.html