New Delhi has become the world’s most polluted city, displacing Lahore from the top of the rankings as air quality in the Indian capital fell to a level classified as hazardous.
Thick smog has settled over the city, affecting traffic and visibility on main roads, Hiru News reported on Friday, citing the Reuters news agency. Lahore, in Pakistan, is now second.
Two readings, two hazard bands
The two authorities measuring Delhi’s air on Friday did not return the same number.
| Source | Air Quality Index | Classification |
|---|---|---|
| IQAir (Switzerland) | 334 | Hazardous |
| Central Pollution Control Board (India) | 403 | Severe |
The gap is not an error by either body. The difference arises from the measurement methodologies the two organisations use and the way each classifies air quality, Hiru reports.
That distinction matters for anyone reading the headline figure: a single “Delhi AQI” number does not exist for Friday, and the two readings place the city in different official hazard bands while describing the same air.
Why Delhi’s air fails every winter
Rising pollution in northern India and neighbouring Pakistan during the winter months is a seasonal pattern rather than an isolated event.
In cold weather, heavy cold air traps emissions near the ground — vehicle exhaust, dust from construction, and smoke from the burning of agricultural waste — holding them in the atmosphere instead of dispersing them.
Sourcing note
Two verified newsrooms carry this story and both date to Friday 13 November, but they contribute unequally.
The substance above — the rankings, both index figures and the explanation for the discrepancy — comes from Hiru News, reporting Reuters. Al Jazeera’s filing is a video newsfeed item, published on 13 November under the headline “Delhi overtakes Lahore as world’s most polluted city”; it independently confirms the ranking change and the date but carries no accompanying text, so no figure in this report rests on it.
Reuters itself is the originating wire. This desk reached Al Jazeera and Hiru directly and did not fetch a Reuters filing, so the agency is credited as Hiru describes it rather than cited as a source.
Not reported
Neither filing gives Lahore’s index reading for Friday, so the margin between the two cities is not established. Neither reports whether Delhi authorities have triggered emergency restrictions such as school closures, construction halts or vehicle rationing, and neither gives a forecast for how long the smog is expected to last. No health advisory or hospital admission figure appears in either account.
