CHENNAI: Chennai air pollution aggravated on Bhogi day on Tuesday as hundreds were seen lighting bonfires contributing to increase in carbon emissions.
A few morning flights were delayed as a thick blanket of smog engulfed the city reducing visibility.
At 11 am, Air Quality Index (AQI) was 170 enough to cause breathing discomfort to people with lung problems and asthma. This is the second consecutive day when air pollution spiked under unfavourable weather conditions. Tamil Nadu Pollution Control Board (TNPCB) data showed a minimum AQI value of 155 (moderate) to maximum value 349 (very poor).
With 91 per cent humidity, a cold night with minimum temperature dropping 2.5 degrees below normal, absence of wind and pollution from Bhogi bonfires and other usual sources, Tuesday was perfect day for smog to hit the city. Even by noon, when the sun was out, smog refused to move away and kept pollution levels high.
The monitoring stations at Manali and Alandur showed that PM 2.5 concentration spiked as high as 500 µg/m3 (micrograms per cubic metre), which is extremely hazardous. Even in Velachery residential area, PM 2.5 peaked to 450 µg/m3. The National Ambient Air Quality (NAAQ) standard for PM 2.5 is 60 µg/m3.
Meanwhile, TNPCB conducted air quality survey for 24 hours at 15 locations. Based on the report, the PM2.5 level was in the range of 72-184 µg/m3, while PM10 was in the range of 146-274 µg/m3 as against the prescribed standard of 100 µg/m3. TNPCB along with corporation officials and police conducted night patrolling by 30 teams. Burning of waste material was noticed in some places and it was put out.
Greater Chennai Corporation officials seized plastic waste and waste tyres kept for burning. More than 1.25 tonnes of waste tyres which was kept for burning were seized and will be sent to Common Hazardous Waste Management Facility at Gummidipoondi. Experts say power plants in North Chennai are the major source of pollution.