KOLKATA: Noise may have been the primary irritant on Diwali night, but it was the air that turned foul enough to kill. Figures recorded by an automatic air monitoring station situated on the south-western fringes of the city are so scary that some Western diplomats stationed in the city spent all of Sunday indoors to avoid breathing the toxic air. According to the state pollution control board's automatic station at Budge Budge, the peak PM10 count on Diwali night was at 2am when it reached 960.4 gm3, nearly 10 times the permissible standard of 100 gm3. An hour earlier, it was 926 gm3. The count persisted beyond 900 gm3 till 3am. It was only after 4am that a gradual dip was noticed.
PM10 or particulate matter of 10 micrometre or less diameter are 40 times finer than human hair and can enter our respiratory system unhindered causing breathing difficulty and aggravating asthma.
While the pollution level at Budge Budge is shocking, environmentalists and health experts are convinced it was worse in Kolkata proper as residents here are socio-economically better off and therefore spend more on crackers and fi reworks than the average middle class resident of Budge Budge. Some believe the PM10 in places like Behala, EM Bypass and Kalindi would have easily surpassed 1,000 gm3 but the measurement never got recorded due to lack of automatic stations. They also point out that the recorded level would have been much higher had the city not experienced sporadic showers over the festive weekend. The city has only two automatic PCB stations that constantly monitors air quality. One is at Budge Budge and the other at Victoria Memorial Hall, which is set amidst verdant greenery and is essentially a non-residential locality where there is hardly any Diwali celebration. Yet, the PM10 count at Victoria station at 1am was 246 gm3, which is nearly two-and-a-half times the permissible limit.
While the readings from the twin stations indicate the extent and intensity of ambient air pollution, PCB does not validate the raw hourly data that is uploaded automatically and instead publishes an average of 24 hours. Environment experts though believe the raw data lays bare the exact pollution level in the city and show how Diwali celebration can be a deadly pollutant. "On Diwali night, people started bursting fireworks a little late. Hence, the pollution level began soaring past midnight and continued till 4 am," said Somendra Mohan Ghosh, an air-pollution expert.
Environment activists have seized on the data to point out the danger of fireworks that has always been under-estimated. "PCBs across the country issue warnings against high decibel fireworks. But none of them point out that they also cause heavy air pollution. It is high time that each pack of fireworks carries a measure of the fume it will emit. Those who argue in favour of fireworks say it is a matter of just one or two nights and cannot cause any long-term harm. But we have ignored the issue for long and continue to behave recklessly. The damage caused by one night takes nearly a month to heal.
By that time, pollution from other sources increases," said Arup Maity, an environment activist anti-fireworks campaigner who holds camps at Champahati and Nungi so that fire-works manufacturers stick to low-cost, low-emission fireworks only.
