Air quality falls in first 10 days of the year
Calcutta: The city's air quality has been found to be consistently "very poor" since the start of the cold spell this month, prompting the Central Pollution Control Board (CPCB) to call for a "graded response action plan" like Delhi has been forced to adopt.
Pollution control experts said that air of similar quality as Calcutta's would have required Delhi to carry out a series of corrective actions under the plan imposed through a judicial order.
"Very poor air quality based on PM2.5 data from manual stations should be considered as a grave threat since the readings would be higher if measured by automatic stations. Calcutta should immediately prepare a graded response action plan and implement it to improve air quality," Dipankar Saha of the CPCB said .
When Metro pointed this out to environment minister and mayor Sovan Chatterjee, he said he would "discuss the issue with the authorities". Sources said the state government would convene a meeting on January 17 to assess the deterioration of air quality.
State pollution control board data shows that the city's average air quality index (AQI) was about 328 in the first 10 days of the month, based on readings from four manual stations that calculate the index on the basis of PM2.5, the most potent air pollutant in terms of its capacity to invade the deepest crevices of the lungs and trigger multiple diseases.
The individual averages of all four stations - in Behala Chowrasta, Minto Park, Moulali and Shyambazar - are in the range of 312-338. AQI readings from 301 to 400 are considered "very poor", a stage just better than the worst air quality possible.
According to the graded response action plan in place for Delhi, "very poor" air quality for two consecutive days warrants a series of actions to minimise air pollution.
Calcutta has so far seen little response from the authorities despite chief minister Mamata Banerjee warning senior officials to ensure that the city does not slip into a Delhi-like toxic air coma.
"There was a meeting on this in Nabanna sometime ago but nothing on the ground has been done so far except forming a committee under the municipal commissioner to look into it," a senior official of the environment department said.
Calcutta is the country's first metro to come out with an action plan to combat air pollution with alternative automobile fuels two decades ago. Today, it is among the last big cities remaining to make the switch to a cleaner option like compressed natural gas (CNG).