Answer: Lahore
Notes: Lahore, Pakistan, was ranked the world’s most polluted city with an Air Quality Index (AQI) of 312, reaching hazardous levels, according to Swiss tech firm IQAir. The PM2.5 concentration was 190.5 micrograms per cubic meter, which is 25 times higher than World Health Organisation (WHO) safety limits. Lahore surpassed Delhi (AQI 220) and Kolkata (AQI 170) in global pollution charts. Smog caused by vehicular emissions, industrial pollution, and crop residue burning has worsened between October and February.
