What are PM and AQI?
PM is the abbreviation for particulate matter, mostly particles of dust and combustion products, that are added to the air from by construction activity, fires of all kinds, petrol and diesel vehicles, industry and power plants. The numbers with PM indicate the size of these particles, measured in thousandths of a millimetre, or micrometre. PM10 thus refers to particles whose diameter is less than 10 micrometres, and PM2.5 to particles that are less than 2.5 micrometres in diameter. Micrometre is abbreviated as µm.
PM10 consists of coarser particles that settle down over a day or two and are washed down by rain; PM2.5 particles are far more dangerous in that they stay aloft for longer periods of time, are easily carried by light winds and worst of all, can enter the bloodstream—and thus every organ—through the lungs.
PM, besides being a Grade I carcinogen, has deadly effects on the respiratory and cardiovascular systems of the human body, causing every imaginable disease, including asthma, heart attack, low birth weight, stroke and arteriosclerosis.
PM pollution is not just a health concern, it is a mortality issue. A 2013 study of over 3 lakh Europeans in nine countries revealed that there was no safe level of particulates and that for every increase of 10 ?g/m3 in PM10, the lung cancer rate rose by 22%. For PM2.5, a 36% increase in lung cancer was associated with per 10 ?g/m3 rise in atmospheric concentration.
AQI, or Air Quality Index, is a colour-coded scale devised by the government in 2014 that measures atmospheric concentrations of eight major pollutants, including PM, and relates them to health standards and implications to produce an easily understandable and relatable value for citizens.
Here’s what PM and AQI translate into for us:
|AQI Category, Pollutants and Health Breakpoints
|AQI Category (Range)
|Moderately polluted (101–200)
|Very poor (301–400)
||Associated Health Impacts
||May cause minor breathing discomfort to sensitive people.
|Moderately polluted (101–200)
||May cause breathing discomfort to people with lung disease such as asthma, and discomfort to people with heart disease, children and older adults.
||May cause breathing discomfort to people on prolonged exposure, and discomfort to people with heart disease.
|Very poor (301–400)
||May cause respiratory illness to the people on prolonged exposure. Effect may be more pronounced in people with lung and heart diseases.
||May cause respiratory impact even on healthy people, and serious health impacts on people with lung/heart disease. The health impacts may be experienced even during light physical activity.
The too little, too late Indian response was in evidence as the Delhi government announced odd-even rationing of privately owned cars from November 13 under the Graded Response Action Plan (GRAP) that was officially imposed in Delhi-NCR on Thursday. The bad news didn’t stop: a change in the wind direction is set to add further ‘poison’ to the national capital’s air on Friday, officials said.
As Delhi-NCR suffocates, Union Health Minister JP Nadda is in Himachal Pradesh and Union Environment Minister Harsh Vardhan is in Goa
Delhi Transport Minister Kailash Gehlot announced the third phase of the odd-even scheme from November 13 to 17. However, according to the members of the Supreme Court-appointed Environment Pollution Prevention and Control Authority (EPCA), November 13 is too late as the “emergency or severe-plus” category under GRAP calls for immediate implementation of the odd-even car rationing scheme.
“We had been telling them (Delhi government) to stay ready since last week and even during Tuesday’s EPCA meeting… The Delhi government said it was prepared to roll out the odd-even right away… Now they are saying they can roll it out only on Monday (November 13). This won’t help much,” CPCB Member Secretary and EPCA Member A. Sudhakar said.
Off the charts
The “emergency” or “severe-plus” situation arises after the major pollutants — PM2.5 and PM10, or particles in air with diameter less than 2.5 and 10mm, remain above 300 and 500 units, respectively, for at least 48 hours. The Central Pollution Control Board (CPCB) on Thursday informed that both PM2.5 and PM10 had been beyond the “safe limits” for the past 52 hours or since 7 a.m on Tuesday, November 7.
On Thursday (since Wednesday evening), all the 10 monitoring stations of the System of Air Quality and Weather Forecasting and Research (Safar) recorded “beyond severe” or 500-plus units of PM10 and PM2.5. As per SAFAR, the average PM2.5 was 546 units and PM10 was 895. According to the CPCB, at 5 pm, the average PM2.5 reading on the Air Quality Index (AQI) in Delhi-NCR across 20 active stations (including Alwar in Rajasthan) was 478 units (on a scale of 0 to 500).
The safe limit for PM2.5 and PM10 as per international standards is 25 and 60 microgrammes per cubic metre, while as per national standards it is 40 and 100 units, respectively.
The alarming pollution in Delhi has led to at least 20 per cent increase in the number of persons complaining of cardiac/respiratory problems this week, officials said on Thursday. “There has been around 15 to 20 per cent increase in number of patients seeking treatment for respiratory and cardiac issues,” All India Institute of Medical Sciences (AIIMS) Director Randeep Guleria told IANS.
Similarly, Safdarjung Hospital witnessed a 15 per cent rise in number of patients while Fortis Hospital in Vasant Kunj area recorded 25 per cent increase in patients with breathing problems. Sir Ganga Ram Hospital had on Wednesday indicated rise in number of such patients by 25-30 per cent.
Speaking to reporters earlier, the AIIMS Director had warned that about 30,000 persons may lose their lives in the National Capital Region alone due to current pollution levels, numbers which, he said, he had extrapolated from the number of hospital admissions. Guleria also likened the current environmental situation in Delhi with the “Great Smog of London in 1952” that was “estimated to have killed nearly 4,000 persons within a week”.
It’ll get worse before it gets better
Meanwhile, forecasting some relief for Delhi-NCR from November 14 onwards, the India Meteorological Department (IMD) said rain in parts of Haryana, western Rajasthan, Uttar Pradesh and Punjab would help disperse the effluents, thereby normalising the air quality in Delhi.
“Relief is likely from Sunday, when the wind speed would increase. However, the western disturbance, which is expected to arrive in this region from November 14, would bring major relief as it could rain. This is so far the best hope under the present conditions,” Charan Singh, weather forecast chief at IMD, told IANS.
However, the relief would come only after Delhi has seen its worse, as air quality in the capital, which is already “beyond severe”, is set to deteriorate further since the light winds from Punjab and Haryana started entering Delhi on Thursday.
As the stubble burning continues unabated in Punjab and Haryana, which is also a major cause of the present air quality situation in Delhi, the winds coming from there would further affect the air in Delhi-NCR. According to the IMD and private weather forecasting agency Skymet, the wind speed is less —five to 10 kmph, but this is enough to bring effluents and not disperse them due to its low speed.
The inevitable committee
The Union Environment Ministry on Thursday formed a seven-member committee to work out short and long -term measures to fight air pollution. The Union Ministry held a meeting headed by Environment Secretary C.K. Mishra along with the Supreme Court-appointed Environment Pollution (Prevention & Control) Authority (EPCA) chairman Bhure Lal and member Sunita Narain, along with officials from the Central Pollution Control Board (CPCB). The seven-member committee which will be headed by Environment Secretary Mishra also includes Secretary Science and Technology Prof Ashutosh Sharma, Secretary Department of Biotechnology Prof K. Vijay Raghavan, Chairman CPCB S.P. Singh Parihar, Chief Secretary, Delhi M.M. Kutty.
Gadkari says more research needed
Road Transport and Highways Minister Nitin Gadkari on Thursday said thorough research was needed to find the cause of rising pollution levels in the National Capital Region. Stressing that smog had engulfed the city this year despite a ban on crackers and restrain on burning of crops, he said research is required to find out the reason behind the rising pollution levels and that his Ministry will offer all possible help for such research, a government statement said. Gadkari said directions have been issued to project directors, contractors and field-level officials working on highways projects around the national capital to take stringent steps to check pollution arising out of the construction work.
Amarinder repeats his stubble plea
Punjab Chief Minister Amarinder Singh on Thursday wrote to Prime Minister Narendra Modi seeking compensation for farmers for crop residue management to check the dangerous trend of stubble burning, which has triggered a major smog crisis in the northern belt of the country. Amarinder Singh also requested the Prime Minister to convene a meeting of Chief Ministers of the affected states along with the Union Ministers for Agriculture, Food and Environment on the issue. Reiterating his request, earlier raised in a letter on July 5 this year, the Chief Minister sought the Prime Minister’s intervention for arresting the problem of paddy straw burning by providing a bonus of Rs 100 per quintal as incentive to compensate the farmers to manage the crop residue scientifically.
Back to normal soon, environment minister says from Goa
Air quality levels in the national capital will come back to normal within the “next few days”, Union Environment Minister Harsh Vardhan, an MP from Delhi, said on Thursday. “Whether the steps which have to be taken by the Delhi government, they should be doing it in complete, total sincerity and similarly the state governments of Haryana, Punjab, Rajasthan.. They all have to step in to fulfil their part of the responsibility. And I am sure in the very near future, in the next few days, things will return to normal,” he told reporters on sidelines of an event organised at the National Institute of Oceanography near here.
Kejriwal sticks to stubblepointing
Delhi Chief Minister Arvind Kejriwal on Thursday blamed stubble burning for the “severe” air quality and said the neighbouring states of Haryana and Punjab should come together with Delhi to find a solution. Kejriwal had on Wednesday written to his Haryana and Punjab counterparts for a meeting on the issue but Punjab Chief Minister Amarinder Singh, in an exchange of tweets, declined it saying air pollution level in the National Capital Region wasn’t an inter-state matter and needed the Centre’s intervention. “I haven’t yet got a chance to meet the two Chief Ministers,” Kejriwal said after inaugurating 20 Continuous Ambient Air Quality Monitoring Stations here. “This one month period from the mid-October to mid-November, when farmers burn the stubble, the whole of North India and not just Delhi turns into a gas chamber,” he said. “In September this year, the PM10 was recorded at 300 units and PM2.5 was 160. Now these figures have gone up to 940 and 750. This certainly hasn’t happened due to the local problems,” he explained.
High Court calls for cloud seeding
The Delhi High Court on Thursday said there was an “emergency situation” vis-a-vis pollution in Delhi-NCR region and asked the Delhi government to consider vehicular odd-even scheme and cloud seeding to induce artificial rain. The court also asked the Centre to hold meetings with Delhi and National Capital Region authorities to bring in short-term measures to control pollution immediately and to submit a report to it on November 16, the next date of hearing. A Division Bench of Justice S. Ravindra Bhat and Justice Sanjeev Sachdeva also directed the Chief Secretary in the Ministry of Environment and Forest and Climate Control to call an emergency meeting with his counterparts in Delhi, Haryana, Punjab, Rajasthan and Uttar Pradesh and pollution control agencies within three days to discuss ways to curb pollution.
(Reproduced tweets do not reflect Lokmarg editorial policy)