Delhi has overtaken Lahore as the world’s most polluted city, with air quality reaching hazardous levels on Friday and visibility falling as thick smog settled over the Indian capital, home to about 20 million people.
Swiss group IQAir put Delhi’s air quality index (AQI) at 334, a “hazardous” reading, making it the most polluted major city in the world. The group measures pollution by the concentration of toxins in the air, and says an AQI of up to 50 is considered good, with little or no health risk.
Indian regulator records higher reading for Delhi
India’s official Central Pollution Control Board gave a higher AQI of 403 and rated the air “severe”. The two readings differ because the Swiss and Indian measurements use different AQI scales and methods for calculating and classifying pollution.
Also read: Lahore stays top of polluted cities list amid poor air quality · Lahore tops global pollution ranking amid toxic smog
Smog hides street lights and traffic in Delhi
Videos from news agency ANI showed cars and motorcycles emerging from dense smog, which also appeared to obscure street lights on the city’s main roads.
Pollution is a seasonal problem across much of northern India and neighbouring Pakistan. Winter’s cold, heavy air holds in vehicle emissions, construction dust and smoke from agricultural burning.
