New Delhi Smog “Rivals 1952 London”

The PM 2.5 concentration in New Delhi, India is more than twice of Beijing, China, previously the world’s most polluted city.

AsianScientist (Nov. 29, 2017) – By Ranjit Devraj – Pollution levels in the Indian capital this month have rivalled 1952 London, when smog killed around 4,000 people, pollution experts say.

On the worst day, November 8, several monitoring stations in New Delhi reported an Air Quality Index (AQI) of 999, far higher than the upper limit of the hazardous band of 500. Flights and train services had to be cancelled because of poor visibility and several pileups were reported as vehicles slammed into each other or crashed into trees and electric poles.

The pollution levels meant that citizens were forced to retreat indoors or flee to safer environments in the nearby foothills of the Himalayas.

By November 21, the AQI had improved though still at a hazardous 326. There are fears that as winter intensifies, the situation could return to “extremely hazardous” again.

Through the entire crisis, officials shied away from declaring a public health emergency and dismissed warnings issued by doctors, concerned locals and international agencies as alarmist.

“I am not saying we shouldn’t do anything about it—everyone has to respond, but there is no need to spread panic among the people,” Harsh Vardhan, federal minister for science and technology and a physician, told television interviewers.

Vardhan’s response showed the reluctance or inability of the government to do anything about a meteorological phenomenon called atmospheric inversion that hits northern India in winter.

Atmospheric inversions are formed of layers of warm air that trap pollutants closer to the surface of the earth and prevent them dispersing into the troposphere, especially when there is very little wind or air movement. New Delhi, among several cities around the world that suffer this phenomenon, is routinely hit during the November—February winter when temperatures fall to single digits.

What is new is that the amount of pollutants released into the stagnant winter air has been increasing steadily along with the number of vehicles on the roads and construction activity. The last five years also saw the introduction of a new industry—waste-to-energy plants to incinerate the 10,000 odd tonnes of municipal solid waste generated daily by New Delhi’s 25 million residents.

Alarm bells first began ringing in 2014 when a WHO study of ambient air pollution in 1,600 cities across the world found New Delhi the worst. This was especially in respect to respirable suspended particulate matter (RSPM) or PM 2.5—which can enter the blood stream via the lungs.

The WHO study revealed, among other things, that New Delhi had PM 2.5 at concentrations of 153 micrograms as compared to 56 micrograms over Beijing, which long held the title for the world’s most polluted city. While Beijing and other cities have been proactively addressing the problem of air pollution, the same cannot be said for New Delhi.

If anything, government policies seem to favour polluting activities rather than discourage them. For example, a new waste management policy encourages incineration and already three waste-to-energy plants are functional with three more in the pipeline. Public protests and litigation against the use of waste incinerators have been ignored and the plants continue to burn unsegregated waste.

It took a Supreme Court order, earlier this year, to stop the use of petroleum coke or petcoke—a notoriously dirty fuel—by thousands of small industries around the capital. But, actual implementation of the order has been difficult, says Anumita Roychowdhury, pollution research leader and campaigner for clean air at the non-profit Centre for Science and Environment (CSE).

Petcoke has far more sulphur content than coal while natural gas has none. But general service tax (GST), now being rolled out in the country as part of tax reforms, seems to favour petcoke over gas. Thus, while clean natural gas attracts a 30 percent tax, coal is charged five percent and petcoke 18 percent. Such policies contrast with the steps taken by China to limit the use of petcoke and decrease reliance on coal as industrial fuels.

Other factors contribute to Delhi’s winter smog—notoriously, the burning of agricultural residues by farmers in the neighbouring state of Punjab. But there is little evidence that this is a bigger factor than those originating within the city. Indeed, Punjab chief minister Amarinder Singh told The Hindu newspaper this month that the blame lay on “urban pollution caused by mismanaged transportation and unplanned industrial development”. Singh has asked the central government to provide Punjab’s farmers with incentives to stop them from burning crop stubble.

The last word on what might be responsible for Delhi’s suffocating winter smog comes from the Indian Institute of Technology – Kanpur (IIT-Kanpur), which, in a study released last year, said vehicular exhaust contributes as much as 25 percent, biomass used as fuel 26–17 percent, and the burning of municipal waste about 8–9 percent.

Whatever the cost, most agreed that the smog is taking toll on the health of people in Delhi and possibly shaving their life spans by several years. A UN Environment Programme report due for release in December says that air pollution is the single greatest environmental risk to health and that some 6.5 million people die prematurely because of it.

Randeep Guleria, director of the prestigious All-Indian Institute of Medical Sciences (AIIMS) and a pulmonology specialist, says that the smog in November was comparable to the Great London Smog of 1952 which left an estimated 4,000 people dead.

Such pronouncements by experts have been dismissed by the government. The IIT- Kanpur study had called for “an integrated pollution control approach in the region,” but the November smog showed that it continues to be business as usual.


Source: SciDev.Net; Photo: Pixabay.
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