Delhi overtakes Lahore as world's most polluted major city as air quality deteriorates

Delhi has surpassed Lahore to claim the title of the world's most polluted city, according to recent air quality readings. The Indian capital's air quality index (AQI) reached a hazardous level of 334, making it the most polluted major city globally, as reported by Swiss air quality monitoring group IQAir. An AQI reading of up to 50 is considered good, indicating minimal health risk.

India's official Central Pollution Control Board (CPCB) recorded a higher AQI of 403 in Delhi, classifying the air quality as "severe." The discrepancy between the Swiss and Indian readings is attributed to the different AQI scales and methodologies used. By 11am PKT, Delhi's AQI had slightly improved to 208, while Lahore, the previous most polluted major city, had an AQI of 155.

The smog in Delhi, caused by cars, motorcycles, and vehicle emissions, construction dust, and agricultural burning, obscured street lights and vehicle movements. Lahore's pollution levels were significantly higher this week, with an average PM2.5 concentration of 126 micrograms per cubic metre, exceeding the WHO's 24-hour guideline value.

Satellite data revealed 18,825 fires in Punjab, Pakistan, with 89% of them classified as crop-residue burning. Although the report did not establish the precise contribution of crop-residue burning to urban pollution, the association highlighted the role of stagnant weather conditions and reduced atmospheric dispersion in exacerbating the pollution problem.