NEW DELHI — Loni, in Uttar Pradesh’s Ghaziabad district on the edge of the National Capital Region, has drawn urgent attention after IQAir’s 2025 World Air Quality Report ranked it the world’s most polluted city with an annual average PM2.5 concentration of 112.5 µg/m3. The finding has sharpened pressure on authorities to move faster in a pollution belt where dust, traffic, waste burning, industry and seasonal weather traps can push exposure into dangerous territory, March 24, 2026.
The report said Loni’s annual PM2.5 load was nearly 23% higher than in 2024 and more than 22 times the World Health Organization’s annual PM2.5 guideline of 5 µg/m3. It also found that only 14% of the world’s cities met that benchmark in 2025, underlining that Loni’s ranking is part of a wider global and regional air-quality crisis — but one that now places a relatively little-known NCR town at the center of the conversation.
Why Loni air pollution became a regional warning
Loni’s designation matters because it sits inside the same airshed as Delhi and the rest of NCR, where emissions do not respect district boundaries. The CPCB’s central control room tracks Loni as a separate monitoring location, reinforcing that the town’s pollution burden is visible in official public data and not merely folded into Ghaziabad’s citywide averages.
The scale of the governance challenge is also clear from a March 2026 CAQM enforcement review, which focused on the same sectors long associated with dirty air across Delhi-NCR: vehicular congestion, road dust, construction and demolition waste, open burning of municipal waste and biomass, industrial emissions and the need to expand continuous monitoring stations. For Loni, that means the problem is unlikely to yield to a single crackdown or a single season’s weather.
What Loni air pollution data shows over time
This did not erupt overnight. In a 2021 Hindustan Times report, officials discussed moving Loni’s monitoring station after it repeatedly posted some of Ghaziabad’s worst readings. That story cited official records showing annual PM2.5 levels above 121 µg/m3 in both 2019 and 2020, a sign that the area’s air burden had already been standing out for years.
By early 2025, the warning lights were still flashing. A Centre for Science and Environment winter analysis said Loni was the worst-affected location in the NCR during the 2024-25 winter season, posting an average PM2.5 level of 153 µg/m3. Seen together, those earlier snapshots make the new global ranking look less like a surprise and more like the formal naming of a long-running emergency.
That history also helps explain why the health stakes are so high. Fine particulate matter can lodge deep in the lungs and enter the bloodstream, and long-term exposure has been linked by WHO to cardiovascular disease, respiratory disease and lung cancer. For families in and around Loni, the “most polluted city” label is not just a headline — it is a measure of daily risk for children, older adults and residents already living with asthma or other chronic illness.
What happens next for Loni and NCR
The harder question now is whether the global attention attached to Loni produces sustained action rather than another cycle of short-lived emergency measures. Unless dust suppression, waste handling, cleaner transport, industrial compliance and denser monitoring improve in and around the town, Loni’s 2025 ranking is likely to be remembered not as an outlier but as the clearest warning yet about how deeply the NCR’s air-pollution crisis has spread.
