Kolkata: Air pollution level in the heart of the city continued to be alarming for the third consecutive day since December 31, a West Bengal Pollution Control Board official said on Thursday.
While the Air Quality Index (AQI) was 317 (PM 2.5) at Fort William air monitoring station at 8 pm on Thursday, it was 285 at the Victoria Memorial and 280 at Ballygunje during the same time, the official said.
An AQI between 201 and 300 is considered 'poor', 301-400 'very poor' and 401-500 'severe', while the AQI above 500 falls in the severe plus category.
The AQI was 318 (PM 2.5) at Fort William during the same time on the previous day during New Year celebrations, the official said. At Victoria, it was 284 on Wednesday.
The AQI in this stretch - covering the revelry zone of Park Street-Princep Ghat-Birla Planetarium-Rabindra Sadan - was 'very poor' (301-400) during December 31 evening.
It went up from the 'moderate' category (101-200) on December 26-27 following rains, the official said.
The dip in air quality was caused by a surge in vehicular traffic in the pocket, the official said adding that it is a typical phenomenon during this time of the year and the PCB is taking all measures to contain it.