Delhi Overtakes Lahore as World’s Most Polluted City as Air Quality Drops

Delhi overtook Lahore as the world’s most polluted city on Friday, November 13, as smog thickened across the Indian capital and air quality dropped sharply.

Delhi’s Air Quality Readings

The air quality index (AQI) in Delhi stood at 334 on the IQAir scale, which is classed as hazardous. India’s Central Pollution Control Board put the reading at 403, classed as severe. The two figures differ because the scales and methods used are not the same. Lahore had held the top spot in the ranking until now, though no current Lahore reading was given.

Smog Cuts Visibility

Smog reduced visibility across the city of about 20 million people and appeared to hide street lights on main roads.

Why the Most Polluted City Ranking Changes Every Winter

The pollution is seasonal. Cold, heavy winter air traps vehicle emissions, construction dust and smoke from agricultural burning close to the ground. On the IQAir scale an AQI of up to 50 is considered good, with little or no health risk, so readings above 300 mean the whole population is at risk and children, older people and those with lung or heart disease should limit time outdoors.

At a Glance

• Delhi overtook Lahore as the world’s most polluted city on November 13
• IQAir AQI 334 (hazardous); India’s CPCB reading 403 (severe)
• Cold air, vehicle emissions, dust and crop burning are the main causes
• Smog has sharply reduced visibility in the city of about 20 million

Read More: Lahore Air Quality Turns Very Unhealthy: City Tops World Pollution Ranking at AQI 240