India, Dec. 17 -- A marginal improvement in air quality brought brief relief to the residents of Gautam Budh Nagar and Ghaziabad districts on Tuesday, though pollution levels continued to remain in the "very poor" category across the region.

Noida recorded an average air quality index (AQI) of 352 on Tuesday, while Greater Noida stood at 326 and Ghaziabad at 332, according to the official statistics of the Central Pollution Control Board (CPCB) at 4pm daily bulletin.

Despite the improvement, the Noida, which falls under Gautam Budh Nagar district, continued to rank as the second most polluted city in the country for the day. Delhi topped the list with an AQI of 354.

The Central Pollution Control Board (CPCB) classifies an AQI of 0-50 a...