The air quality in Calcutta continued to be 'poor' for the second consecutive day on Wednesday as the particulates hung heavy in the lower air causing breathing discomfort.

In the industrial belts of Dasnagar and Padmapukur in the neighbouring twin city of Howrah, the air quality was classified as 'very poor', an official of the West Bengal Pollution Control Board (WBPCB) said.

The official said the AQI was 245 (PM 2.5) at the air monitoring stations at Fort William, 264 at Victoria Memorial, 276 in Ballygunge area, 220 at Rabindra Sarobar and 243 at Rabindra Bharati University at Sinthi area in Kolkata, all classified as 'poor' on Wednesday afternoon.

In Howrah's Dasnagar, the AQI was 356 while it was 354 at Padmapukur, categorised as 'very poor' in the environmental parlance which denotes breathing discomfort for everyone and serious breathing problems for the asthmatic patients or people with pulmonary issues, the official said.

On Tuesday, the AQI was 320 (very poor) at Ballygunge, 301 (very poor) at Salt Lake, while it was 288 (poor) at Victoria.

The AQI was 'moderate' according to records of most air stations on Monday (November 25). It was 259 in the Ballygunge area, which worsened on Tuesday, as it rose to 288.

The official said this was typical of the conditions when winter sets in and the tiny dust particles fail to move up in the air.

An AQI between 200-300 (PM 2.5) is categorised as poor, and 300-400 (PM 2.5) as very poor. 'Poor' air quality signifies danger to health, while 'very poor' air quality means extremely hazardous.

Environmentalist Somendra Mohan Ghosh said the conditions are quite risky even for people without breathing difficulties even in eco-sensitive zones.

"PM 2.5 are deadly fine particles emitted from the transport and allied sectors and are the most significant contributor to the city’s already deteriorating air quality, as shown by a recent study on the emissions inventory of Kolkata’s air quality," he said.

Ghosh said roadside eateries using coal-fired ovens are indeed a major source of air pollutants as the combustion of coal releases harmful pollutants, including, Particulate Matter (PM) that can penetrate deep into the lungs, causing respiratory problems.

The WBPCB is encouraging roadside eateries to switch to cleaner fuels such as LPG or electric ovens, the official said.

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