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Breathless in the Capital

Hazardous haze continues to hang over Delhi blurring its skyline and choking its people.

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Aditi Tandon in New Delhi

Hazardous haze continues to hang over Delhi blurring its skyline and choking its people. For a week now, air quality index (AQI) in the national Capital has hovered around severe levels forcing pulmonary experts to ring alarm bells.

“Breathing in Delhi means dying. If you want to survive, you must either stop breathing or leave,” says Dr Arvind Kumar, founder trustee Lung Care Foundation, and chairman, chest surgery, at Gangaram super specialty hospital.

To drive home his point, Kumar recently created a pair of lungs artificially pumping these with the air that Delhi residents breathe. Between November 3 and November 8, the colour of the lungs changed from pure white to jet black. “That’s what’s happening to everyone’s lungs in Delhi. I am perfectly healthy and can climb eight floors without a pause. But I have been using an inhaler to breathe for five days. All my family members have been using inhalers and they are all healthy people without any disease history. Current levels of particulate matter pollution in the city are inhuman. Anywhere in the West, a city under such a lethal blanket of haze would have shut down,” says Kumar.

For most part this year, Delhi’s AQI has remained poor, very poor or severe.

The current AQI in the capital is in the red, signaling severe levels that can harm healthy people with no history of respiratory problems.

AQI prescribes colours to air pollutants on the basis of their ambient concentration and health impacts. It provides 24-hour measurements for eight pollutants namely PM10, PM2.5 (particulate matter less than 10 microns and 2.5 microns); NO2 (nitrogen dioxide), SO2 (sulphur dioxide), CO (carbon monoxide), O3 (ozone), NH3 (ammonia) and Pb (lead).

While the enhanced concentration of each of the above is dangerous, doctors are particularly wary of PM10 and specifically of PM2.5. WHO standard for permissible PM2.5 air levels is 10 micrograms per cubic metre (µg/m3) but India’s corresponding standard is four times higher at 40 µg/m3.

At all of Delhi’s AQI measurement stations, including Indira Gandhi International Airport (Terminal 3) and Anand Vihar, PM2.5 levels have remained above 400 microns post Diwali. It is a severely harmful range considering a 16-year-long research has linked high ambient PM concentrations to increased premature mortality, chronic respiratory disease, emergency visits and hospital admissions, aggravated asthma, acute respiratory symptoms and decrease in lung function.

PM2.5 is of the highest concern as it contains toxic metals and acids and can aerodynamically (being finer than human hair) penetrate the respiratory tract and lodge itself in lungs and blood vessels causing grave harm.

“PM10 contains bigger particles the nose and medical masks can still filter. But masks are useless when it comes to preventing PM2.5 pollution. Only N98 masks can help check PM2.5 provided these are tightly worn. But masks are never worn the way these should be and merely serve cosmetic purpose,” says RS Dhaliwal, Director, Non Communicable Diseases, ICMR, currently studying air pollution link to increased emergency visits by people over a year.

Asked if air purifiers help, ICMR experts say not much as these are unsustainable. “Purifier filters can get choked in hours with current pollution levels in Delhi. Replacements are expensive and therefore unsustainable. No one can maintain purifiers at their maximum air cleaning capacity,” adds Dhaliwal.

As prevention, doctors advise avoiding outdoor activity in early mornings when PM10 and PM2.5 particles are hanging close to the ground due to low temperature, smog and high precipitation. “Windy conditions are good to blow away these particles but winds are rare. Long-term solution lies in reducing pollution from vehicular exhaust fumes, burning of agricultural waste and human carcasses, construction and industrial pollutants. Construction companies must net their sites to prevent dust from entering the atmosphere. That’s the norm in the West,” says Dr Prashant Mathur, director, National Centre for Disease Informatics and Research.

The Lancet Global Health 2018 recently published a research by Ministry of Health, ICMR, and Public Health Foundation of India that shows ambient air pollution has outdone smoking as the top risk factor for chronic obstructive respiratory disease in India. Also, outdoor air pollution was the second highest cause of mortality in India after heart diseases in 2016.

Of the total global DALYs (years of healthy life lost due to disease) due to chronic respiratory diseases in 2016, 32 per cent occurred in India which saw chronic obstructive pulmonary disease cases rise from 28.1 million in 1990 to 55.3 million in 2016.

“Of the DALYs due to COPD in India in 2016, 53.7 per cent were attributable to air pollution, 25.4 pc to tobacco use, and 16.5 pc to occupational risks,” the study concluded.

“If this is the national situation, you can imagine the situation in Delhi. Air pollution is now causing not just respiratory events but also heart diseases, diabetes and lung cancers,” Prof Anurag Agarwal of the CSIR-Institute of Genomics and Integrative Biology, Delhi.

So how does outdoor air pollution affect a normal person? Doctors say it can expose sick people to sudden death and healthy people to illnesses. “Children are especially vulnerable as they breathe double the number of times adults do enhancing their exposure to air pollution. Mark my words. In another five years India will be facing an epidemic of lung cancer due to ambient air pollution,” warns Dr Arvind Kumar unless governments wake up and make pollution control a political priority.


Cancer-causing Pollutants

  • Particulate Matter: PM levels have been linked to increase in mortality and hospitalisation cases due to respiratory diseases.
  • Carbon monoxide: Initial symptoms of CO poisoning include headache, dizziness, drowsiness and nausea. These may advance to vomiting, loss of consciousness and collapse on prolonged exposure and may lead to coma or death on continued exposures.
  • Nitrogen dioxide: Prolonged exposure can cause decrement in lung function by way of increased airway resistance.
  • Ozone: It has serious health impacts, can aggravate bronchitis, heart disease, emphysema, asthma and reduce lung capacity.
  • Sulphur dioxide: Causes lungs to constrict.
  • Ammonia: Causes irritation in the nose, throat and respiratory tract. 
  • Lead: A toxic metal whose exposure increases lead levels in blood.

Pollution, the many causes

  • Stubble burning by farmers in Punjab, Haryana and western UP. However, it is not the only reason. Winds carry stubble particles, which get locked in the NCR.
  • Vehicular emissions are increasing, adding hazardous pollutants. 
  • Burning of firecrackers despite the ban.
  • Due to stagnant winds and weather conditions at this time of the year, pollutants get locked in the air, resulting in smog.
  • Reducing green spaces and areas.
  • Over-population is further adding to various types of pollution, air and noise.
  • Poor planning, less investment in public transport and infrastructure.
  • Large-scale construction activities.
  • Industrial pollution, backyard burning and garbage dumps.

PM2.5: the most harmful

WHO standard for permissible levels of PM 2.5 in the air is 10 micrograms per cubic metre (µg/m3). India’s standard is 40 µg/m3. AQI in Delhi showed severely harmful PM2.5 level of 444 at Anand Vihar on November 10, up from very poor level of 325 on November 7 (Diwali day). At IGI (T3), Delhi, PM2.5 level rose from 268 (poor) to 398 (very poor) between November 7 and 10.

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