Delhi air pollution eight times the safe limit day after Diwali
New Delhi: One of the key measures of air pollution in the national capital and its satellite towns like Noida was more than eight times higher than the safe limit on Monday evening, a ‘severe’ air quality that can see healthy people affected with respiratory problems and those with existing diseases seriously impacted.
The national capital also recorded high noise level on Sunday night.
A day after Diwali, the levels of particulate matter (PM) 10 and 2.5 in Delhi were recorded at severe levels of 836.1µg/m³(over eight times the safe limit) and 624.2µg/m³ (nearly 10 times the safe limit) on Monday evening, according to the System of Air Quality and Weather Forecasting and Research (SAFAR) of the Union ministry of earth sciences.
The safe limit of PM 10 is 100µg/m³ and PM 2.5 is 60µg/m³, which means Delhi on Monday witnessed nearly eight times the level of PM 10 and PM 2.5—the deadliest components of air pollution. These fine particles can settle deep in the lungs and be absorbed in the bloodstream, which can lead to respiratory problems, cardiovascular diseases and lung cancer.
The data shows that pollution levels this Diwali were far more dangerous than those recorded last year. As per SAFAR data, last year after Diwali, the PM 2.5 levels were 428µg/m³—nearly six times the safe limit.
Spreading smoke from Diwali fireworks meant that the majority of the 18 air quality monitoring stations spread across Delhi and Noida recorded ‘severe’ air quality levels.
There will be no respite on Tuesday and over next few days with government agencies issuing forecasts of “severe” and “very poor” air quality days.
As per the SAFAR forecast, PM 10 and PM 2.5 levels on Tuesday are expected to be 459.1µg/m³ and 350.2µg/m³. Even after three days, as per the forecast, the PM 10 and PM 2.5 levels are expected to remain ‘very poor’ at 361.09µg/m³ (nearly four times the safe limit) and 215.1µg/m³ (nearly four times the safe limit), respectively. “Very poor” air quality results in respiratory illness to people due to prolonged exposure.
Noida, too, recorded high levels of pollution. As per SAFAR data, the level of PM 10 and PM 2.5 in Noida on Monday evening was 704µg/m³ (nearly seven times the safe limit) and 605µg/m³ (over 10 times the safe limit), respectively.
An analysis released by the Central Pollution Control Board, which is India’s nodal pollution watchdog, revealed “there was no increase in any location with respect to sound level both times during day & night time, as compared to previous year”. But even then, according to the study, the noise levels were above the prescribed norms at majority of the places (where noise levels were monitored) in day time and at all the places during the night time on the Sunday. On Monday afternoon, CPCB released an analysis of the ambient air and noise pollution in Delhi on Diwali.
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“It is not just crackers but their waste, which were burnt at many places on Sunday (Diwali) night. The real time data crossed horrendous levels across all localities in the national capital on Sunday night. Delhi is choked and there is no more room for pollution especially with winter slowly setting in,” said Anumita Roychowdhury, executive director, Centre for Science and Environment (CSE), a Delhi-based environment think tank.
“Apart from smoke, crackers also release toxic metals in environment which are going to come back to use through food chain. Therefore, we need a proper policy for fireworks during winter, including during the wedding season in Delhi-NCR when the use of crackers goes up,” she added.
Experts agree that there are many other factors responsible for high air pollution in Delhi like stubble burning in other northern states such as Punjab and neighbouring Haryana but the spike on Sunday night was certainly due to fireworks.
“Nasa pictures have shown problems of stubble burning. But the rapid build up of pollution between Sunday afternoon and night was due to crackers only,” Roychowdhury added.
“Emissions caused by crackers added to already high PM2.5 levels in the city. Levels were higher than last year as the background concentrations were already high due to outside contributions from agricultural burning. Lower wind speeds and shallow inversion layer can lead to extremely high pollutant concentrations in winters. Regional scale multi-sectoral air quality management plan required for NCR,” said Sumit Sharma, a fellow at TERI, which is a Delhi based think tank working on environment issues.
While the average levels as per SAFAR were nearly eight times higher, the data recorded by the air quality stations of the Delhi Pollution Control Committee (DPCC) showed that levels of PM 10 and PM 2.5 touched scary levels after Diwali.
As per the DPCC data, R.K. Puram recorded PM10 level at 1440µg/m³ on Monday at 2.30am and PM 2.5 level at 844µg/m³ at 9am on Monday morning. At Anand Vihar, the PM10 level touched 1680µg/m³ on Monday at 2.30 am and PM 2.5 level at 883µg/m³ at 2.30 am on Monday. Both R.K. Puram and Anand Vihar are pollution hotspots in the national capital. Another pollution hotspot, Punjabi Bagh, too recorded similar high levels of PM 10 (1560µg/m³) and PM 2.5 (678µg/m³).
Meanwhile, the CPCB analysis of the ambient air and noise pollution in Delhi on Diwali, also said that the PM10 levels was found to have increased in all places in Delhi as compared to 2015.
In Delhi, ambient noise was monitored at 16 locations while ambient air quality was monitored at 11 locations. Countrywide, CPCB monitored ambient noise levels at more than 200 locations and ambient air quality at about 170 locations.
The CPCB analysis revealed that lower wind speed on Diwali in 2016, “caused to have lower dispersive capacity in atmosphere leading to higher concentration of pollutants”.
“The level of pollutants has increased significantly in all places irrespective of parameters attributed to unfavourable meteorological conditions during the entire period,” the CPCB analysis added.