The city’s air quality this winter, especially in December and January, is worse compared with December 2021 and January 2022, data from the Central Pollution Control Board (CPCB) show.
Air emission experts said the data this winter reflect the city’s true air quality. The pandemic-induced restrictions had kept the air pollution level in check last winter.
A recently published report based on CPCB data pointed out that Kolkata’s average air pollution level, particularly of the most toxic fine and ultrafine particulates, went down marginally in 2022 compared with previous years.
According to CPCB data, accessed by The Telegraph, Kolkata’s average air quality index (AQI) in December 2022 was 254, about 26 per cent higher than the average AQI of December 2021, which was 202.
The average AQI for the first 11 days of January was 254. The average AQI for the corresponding period last year was 234.
This newspaper found that two automatic air pollution measuring stations in the city recorded “severe” air quality — the worst quality — during the 24-hour period ending at 8pm on Wednesday.
Other five automatic measuring stations recorded “very poor” air quality during the same period.
All seven stations are run by the CPCB.
An AQI between 401 and 500 is considered “severe”. An AQI between 301 and 400 corresponds to “very poor”, while “poor” air has an index varying between 201 and 300.
Anumita Roy Choudhury, an air pollution expert from the Centre for Science and Environment, recently pointed out that the winter peak of PM2.5 in 2022-23, till recently, was about 26 per cent higher than the 2021-22 winter months.
“The government has to take hard action in key sectors like transport and construction,” she said.