Compared to last year, the national capital suffered from lower air pollution this Diwali on all counts except sulphur dioxide, but experts have warned against increasing use of coloured fireworks.
According to the Delhi Pollution Control Committee (DPCC): "The air and noise pollution levels in Delhi during Diwali festival have been contained. However, marginal increase was observed in gaseous pollutants which may be attributed to weather conditions, vehicular emissions and shift from crackers to more colourful fireworks which contain metallic oxides and emit more carbon monoxide and oxides of nitrogen."
DPCC monitored the air pollution levels at 40 locations and noise levels at 10 locations on Diwali on Saturday. Nitrogen oxide levels were found to have increased at 22 locations across the national capital.
"Though Diwali pollution is reduced in last several years the minimum levels remain very high as compared to the standards. Another major cause of concern is an increase in SO2 (sulphur dioxide) every year (for the last five years)," Vivek Chattopadhyaya of the think tank Centre for Science and Environment (CSE) told IANS.
"People are switching to light-based crackers from noise-based crackers. But for colours, crackers need metals and when such firecrackers explode they release metal fumes which are very harmful, especially for children," Chattopadhyaya said.
As per the Central Pollution Control Board (CPCB) analysis air pollution levels during 2009 were found to be generally lower as compared to Diwali 2008 except sulphur dioxide, which it said could be attributed to more use of sulphur-containing crackers.
As per CPCB, sulphur dioxide range was between 8 mg and 42 mg per cubic metre (mg/m3) this year as compared to 7 mg to 24 mg/m3 in 2008.
Another environmental expert Iqbal Malik said: "Government should have been careful that sparklers coming in market do not have high metallic toxicity. How will people know about it? We observed that sparklers this year had more sparkle and more colours."
"It will be very harmful for people and the environment. Now, people should put pressure on the government to not allow such crackers in the market," Malik, who works on socio-environment issues and is the founder director of the NGO Vatavaran, told IANS.
The data collected by the DPCC shows respirable suspended particulate matter (RSPM) ranged from 316 to 466 micrograms per cubic metre this Diwali.
"The minimum value was observed at Inder Puri and maximum value was observed at Pahar Ganj. The concentration exceeded the standards at all locations," it said.
The CPCB findings further revealed that concentration of all pollutants including noise was at its peak from 9 pm to midnight on Diwali.