Date:29/10/2008 URL: http://www.thehindu.com/2008/10/29/stories/2008102959470400.htm

Tamil Nadu - Chennai

Pollution level higher this year

Deepa H Ramakrishnan and K.Lakshmi

Residents complained of burning sensation in eyes and throat

Photo: K.V.Srinivasan

Smoky affair: Deepavali celebrations in Triplicane, which was the noisiest and most polluted spot in Chennai on Monday. —

CHENNAI: It was a relatively quiet Deepavali this year with the residents opting for more sparkle than sound with while bursting firecrackers. With a chilly mist cover trapping the smoke close to the ground, many residents, however, complained of burning sensation in their eyes and sore throat.

The mist, which continued till Tuesday, was due to a low-level inversion that indicates an increase in temperature in the atmospheric layer within one km from the ground level, according to Meteorological department officials.

Such a misty cover would usually be reported in January and their occurrence this time of the year is rare, the officials said. With the pace of dispersion of the smoke from the firecrackers slow, the air pollution levels were higher than last year.

“Dispersion of smoke was not possible because of the mist. Vehicular emissions compounded the problem,” said an official of Tamil Nadu Pollution Control Board. The Board had established air and noise monitoring facilities at five locations in the city for Deepavali.

The level of sulphur dioxide at the locations - between 14 and 26 microgram/cubic metre - and that of nitrogen oxides - between 20 and 42 microgram/cubic metre – was higher than last year.

Last year, the average level of sulphur dioxide was 10 microgram/cubic metre, while it was 21 microgram/cubic metre this year.

The average level of nitrogen oxides was 37 microgram/cubic metre as against 16 microgram/cubic metre last year. The permissible limits for SO2 and NOx are 80 microgram/cubic metre.

The noise level, at 81.9 decibels, in Triplicane was the highest. The amount of respirable suspended particulate matter (RSPM) in the locality was 437 microgram/cubic metre and total suspended particulate matter (TSPM) was 707 microgram/cubic metre, which were the highest across the city.

The RSPM level in T.Nagar was 419 microgram/cubic metre and TSPM 633 microgram/cubic metre. Nungambakkam recorded RSPM of 419 and TSPM of 491. Sowcarpet recorded RSPM of 370 microgram/cubic metre and TSPM of 534 microgram/cubic metre.

Ayanavaram recorded RSPM of 370 microgram/cubic metre and TSPM of 534 microgram/cubic metre.

The noise level in the city ranged between 69.4 dB and 81.9 dB with the overall average being 74.4 dB.

According to data provided by TNPCB, Ayanavaram followed Triplicane recording 77.2 dB.

It was followed by Nungambakkam with 74.3 dB, Sowcarpet with 70 dB and T.Nagar with 69.4 dB.

A total of 15 teams of TNPCB personnel worked in three 8-hour shifts at the five locations.

The Board started recording the noise levels and monitoring the ambient air quality during Deepavali following a Supreme Court directive.

Apart from irritation in the eyes and throat, the smog affected patients suffering from Chronic Obstructive Pulmonary Disease (COPD) and asthma, said R.P.Ilangho, Senior Consultant Respiratory Physician and Head of the Breathe Easy Clinic, Apollo Hospitals Group.

Asthmatics would have had wheezing and spasms due to air pollution. Persons suffering from COPD would have had coughing and difficulty in breathing, he said.