NEW DELHI: Delhi overtook Pakistan’s Lahore on Friday to become the world’s most polluted major city, as a thick blanket of smog reduced visibility and pushed air quality into dangerous territory across the Indian capital.
Swiss air quality monitoring group IQAir recorded Delhi’s Air Quality Index (AQI) at 334, placing it at the top of its global ranking of major cities and displacing Lahore. IQAir classified the reading as hazardous.
India’s Central Pollution Control Board (CPCB), meanwhile, recorded an AQI of 403 for Delhi and classified the air quality as severe. The two figures are not directly comparable, as the agencies use different scales and methods to calculate and classify pollution levels.
An AQI reading of up to 50 is generally considered good, indicating little or no risk to health. Both Friday’s readings were far above that threshold, highlighting the severity of pollution in the capital.
Videos from Delhi showed cars and motorcycles moving through dense grey smog, while street lights along major roads were barely visible through the haze.
Air pollution is a recurring seasonal problem across northern India and neighbouring Pakistan. During the colder months, stagnant air traps vehicle emissions, construction dust and smoke from agricultural residue burning close to the ground, preventing pollutants from dispersing.
Friday’s ranking represents a snapshot of pollution levels on a single day and covers major cities included in IQAir’s comparison. While the two agencies reported different figures, both indicated severely polluted conditions in Delhi.
The gap between the readings also highlights the differences in how pollution monitoring agencies measure and classify air quality.
(With inputs from media reports)