Diwali razzmatazz has now compelled Delhiites to breathe the air having alarming level of particulate matters in it. The Capital witnessed an upward trend in noise pollution leaving behind other metros like Bangalore, Chennai, Mumbai and Kolkata. However, the city recorded the lowest air pollution level this Diwali in the last five years, according to the Delhi Pollution Control Committee.
Post-Diwali, the city’s air saw a significant rise in particulate matters, classified as PM 10 and PM 2.5, in comparison to the levels last year. “PM 10 level had shown an increasing trend at all the locations on November 3, 2013. This year the values ranged between 796 and 1138 µg/m3 as compared to 748 and 951 µg/m3 during last year’s Diwali,” said SK Tyagi, scientist at Central Pollution Control Board (CPCB). PM 10 are fine particles present in the air having a diameter below 10 micron. Punjabi Bagh recorded the highest PM 10 as well as Sulphur Dioxide levels while Mandir Marg had the least. Even PM 2.5 saw a marginal rise from 233 µg/m3 in 2012 to 293 µg/m3 this year which was highest in RK Puram.
However, the reason for the increase in particulate matter in the air cannot be attributed only to the bursting of crackers, experts opine. The prevailing weather condition on Sunday is also said to have facilitated the concentration of such particles. “Increased PM10 level on Diwali may have been caused also by adverse meteorological conditions. lower night temperature, a lower low wind speed may be the contributing factors,” informed Tyagi.
The height at which these particles mixed with the air was recorded at 197 metre this year, compared to 211 metre in 2012. The average wind speed also decreased from 0.43 metre per second in 2012 to 0.36 m/sec in 2013.
In terms of noise pollution, the national Capital beat several other metro cities. Mayur Vihar Phase II was found to be the noisiest on Sunday at 83 decibels. This was followed by Kamla Nagar and Ansari Nagar recording 81 decibels.
Gaseous pollutants like Sulphur Dioxide (SO2) exceeded the normal level significantly across the city on Sunday evening. Between 8 pm and 11 pm, when fireworks were at its peak, SO2 levels crossed its prescribed levels. Its average concentration also increased from 20 mg/m3 to 88 mg/m3 in 2012 to 35 mg/m3 to 114 mg/m3 this year.
“This year there has been a decrease in the concentration of gaseous air pollutants. The average concentration of Carbon Monoxide (CO) lowered from 1.9 mg/m3 to 7.5 mg/m3 in 2012 to 1.6 mg/m3 to 3.6 mg/m3 in 2013. Oxides of Nitrogen (NO2) also decreased ranging from 67 mg/m3 to 110 mg/m3,” informed an official of Delhi Pollution Control Committee.