Delhi Air Pollution Case Study (2022) Essay & Statistics

Does this photograph need any introduction? Yes. It is India Gate, an iconic monument in Delhi. See how beautiful it looks.

Here is a contrasting image of the same monument taken recently.

The monument is the same. But, it is not visible clearly because of air pollution. Delhi has been notorious for its miserable air quality. The Air Quality Index (AQI) has been consistently bad for more than five to six years. Even today (November 30, 2022), it is unhealthy.

Source – https://www.iqair.com/in-en/india/delhi

An AQI of 198 is unhealthy, even early in the morning. But, then, the AQI starts climbing quickly and reaches more than 300 almost daily, with specific areas crossing 350. That can become unnerving. The data for the past four days should put things in proper perspective. 

Source – https://www.iqair.com/in-en/india/delhi

Source – https://www.iqair.com/in-en/india/delhi

This article discusses air pollution in the Indian national capital in 2022 to understand why it ranks among the world’s most polluted cities. We shall examine and analyze the reasons for Delhi’s air pollution and look at remedial measures to keep the pollution levels under check.

The Primary Causes of air pollution in Delhi

PM2.5 is the leading cause of air pollution in Delhi. The PM2.5 concentration in Delhi currently is 29.5 times the WHO annual air quality guideline value.

PM2.5 Pollution

Various factors contribute to PM2.5 pollution in Delhi. Studies have shown that more than 65% of Delhi’s winter pollution load is because of external factors. The pollution source is from outside Delhi’s geographical boundaries. The burning of agricultural biomass in the neighboring states of Punjab, Haryana, and Uttar Pradesh is primarily responsible for Delhi’s pollution. Generally, farmers burn agricultural stubble at the end of every harvesting season to refresh the soil before the start of the next season. 

Source – https://www.iqair.com/in-en/india/delhi

However, stubble burning is not Delhi’s only source of PM2.5 air pollution. Besides agricultural pollution, Delhi air has to contend with vehicular emissions, industrial pollution, and other issues.

The Center for Science and Environment has analyzed data from various sources to conclude that vehicular emissions contribute to 51% of PM2.5 levels in Delhi. Residential sources contributed to 13%, whereas 11% is due to industrial pollution. Construction activity is responsible for 7% of PM2.5 pollution, followed by the energy sector and the burning of waste at 5%. Road dust accounts for around 4% of PM2.5 pollution.

The analysis confirmed that Delhi’s local sources accounted for 32.9% of the total pollution in the city. Other sources contributing to Delhi’s PM2.5 levels constitute the NCR districts (32.8%), other state districts (25.8%), and biomass burning in Punjab-Haryana-Uttar Pradesh (9.5%).

Traffic congestion in the city contributed to high NO2 levels in the environment. The maximum NO₂ levels were seen in the evenings when the congestion was at its highest. The hourly NO₂ levels were around 76 µg/mg³ to 86 µg/mg³. In contrast, the PM2.5 levels due to stubble burning were around 28 µg/mg³ on average.

The PM2.5 levels are also high during the winter because of the temperature inversion phenomenon. The temperatures in winter are low, and the colder temperatures trap pollutants near the ground. The warmer air rises to the top and sits atop the cold air to trap the pollutants and allergens, causing smog and reducing visibility.

Another significant cause of PM2.5 pollution in winter is the burning of crackers during Diwali, marriage celebrations, and other victory processions taken out by political entities. The cold winter air does not allow these impurities to escape into the atmosphere, forcing people to inhale them. As a result, studies show that the average life expectancy of humans in Delhi has shortened by nearly ten years.

PM10 Pollution

Many people confuse PM2.5 and PM10 and consider them to be the same. But it is not so. PM2.5 pollution originates from combustion-based activities. For example, almost 95% of vehicular emission comprises PM2.5. On the other hand, PM10 pollutants are comparatively larger and arise from mechanical processes. The primary source of PM10 pollutants is road dust, construction site pollutants, and seasonal dust storms.

Source – https://www.iqair.com/in-en/india/delhi 

PM2.5 constitutes all aerosols under 2.5 µm, whereas PM10 comprises pollutants under 10 µm. So, PM2.5 is a subset of PM10. Therefore, PM10 samples show higher pollution density. PM10 was the only size fraction measure in India for a long time until PM2.5 was added to the list in 2009.

PM2.5 vs. PM10

PM10 comprises bigger particles that can irritate your throat, nose, and eyes. It is also inhalable and can deposit on the inner sides of the windpipe. On the other hand, PM2.5 is more dangerous because it can penetrate the deep parts of your lungs and even find its way into your blood.

Is there any safe level for PM2.5 and PM10?

The World Health Organization (WHO) has stipulated safe limits for PM2.5 and PM10 at 5 µg/mg³ and 15 µg/mg³. However, the Central Pollution Control Board (CPCB) average permissible limits are 40 µg/mg³ and 60 µg/mg³, respectively. Compare Delhi’s average PM2.5 and PM10 levels, and you will realize how dangerous it is.

Source – https://www.statista.com/statistics/1284233/average-monthly-pm25-in-cities-in-india/

This graph shows Delhi is the most polluted city compared to other prominent Indian metros. First, the PM2.5 level is consistently higher than the WHO and CPCB stipulations. Secondly, you can notice that the pollution level peaks during the winter months, thus, proving the temperature inversion theory right.

Source – https://aqicn.org/city/delhi/

Source – https://aqicn.org/city/delhi/

The darker the squares, the higher the pollution levels. So, these real-time images prove that the air quality in Delhi has been consistently bad in 2022, with the winter months being the most dangerous. The monsoon months from July to October have been less risky.

Chemical Pollution

We have discussed particulate matter pollution in Delhi by analyzing PM2.5 and PM10 pollution levels. However, besides PM2.5 and PM10, chemical pollution is a significant cause of pollution in Delhi. Chemical pollution constitutes toxic gases like Ozone (O₃), Nitrogen Dioxide (NO₂), Sulphur Dioxide (SO₂), and Carbon Monoxide (CO).

Research shows particulate matter pollution peaking during winter. So does that make the summer months less susceptible to pollution? No, because surface ozone pollution is at its highest in summer.

2022 has witnessed an unprecedented summer, with temperatures much higher than usual. The increased use of air conditioners and refrigerators has resulted in higher VOC emissions, a primary constituent of surface ozone. Besides, vehicular emission is a significant contributor to VOCs. Other VOCs and nitrogen dioxide sources include power plants, factories, and natural sources like plants.

Records show that the surface ozone level was consistently above safe limits for 85 days from March to May 2022. Mumbai was second with 75 days, and Hyderabad and Kolkata’s surface ozone levels exceeded the safe limit for 43 days each during the same period. South Delhi was the most affected region, followed by JLN Stadium, RK Puram, and Nehru Nagar. Noida, considered part of Delhi, was the most significant hotspot on the outskirts of the national capital.

Though the chemical pollution levels in Delhi in 2022 have been critical, they are nowhere as dangerous as particulate matter pollution. But together, they combine into a deadly combination that has endangered people’s lives in Delhi.

Bhalswa Landfills

Source – https://www.livemint.com/news/india/delhi-bhalswa-fire-releases-toxic-chemicals-locals-demand-landfill-removal-11654311866396.html

Bhalswa Landfill is a dumping ground for different kinds of waste generated in Delhi. This landfill has been in use since 1984. This landfill, spread over 52 acres, has debris over 62 meters high. While it has grown beyond capacity, the Delhi Administration has done little to manage the waste. As a result, the trash starts decomposing, and the area is prone to fires.

The smoke generated from burning toxic waste material has unacceptable levels of carbon monoxide, hydrogen sulfide, and other poisonous gases. Moreover, it affects people living in its vicinity and the surrounding areas because the wind carries these gases almost all over Delhi.

Stagnant Winds

Delhi has another climatic issue of stagnant winds. Sometimes, there is no wind movement at all. It forces the pollutants to concentrate in specific areas and pollute the air. On the other hand, a moving wind would have dispersed the contaminants away from the city.

Geographic Location

Delhi’s unique geographic location is one of the principal reasons for its pollution problems. Delhi lies landlocked between Punjab, Haryana, Uttar Pradesh, and Rajasthan. Besides, the Himalayas in the north traps the winds and does not allow the pollutants to escape.

In contrast, cities like Mumbai and Chennai have vast open coastal areas that enable pollutants to escape over the sea. Delhi has a significant disadvantage in this regard.

Population Explosion

The massive population growth has also contributed to polluting Delhi’s air. Census figures show that Delhi’s population increased from 16.7 million in 2011 to more than 20 million in 2019. As a result, Delhi has more vehicles, industrial products, and amenities that contribute significantly to air pollution.

Inadequate public transportation

While Delhi has an impressive bus fleet, it is insufficient to cater to its growing population. As a result, the Delhi roads have more private vehicles, contributing to air pollution. A better and cheaper public transport system can solve matters.

We shall discuss the effects of air pollution in Delhi in the following section.

How air pollution affects Delhi residents?

As discussed, PM2.5 pollutants are minute enough to penetrate the respiratory system and lodge themselves deep inside the lungs to cause respiratory damage. In addition, these particles can irritate and corrode the inner sides of the alveolar wall and affect lung functioning. So if you have a history of asthmatic problems, it can exacerbate the problem and end up as a severe respiratory ailment, leading to death.

Studies have shown that aerosols with diameters smaller than 10 µm can have an adverse impact on human health. The PM2.5 particles have large surface areas and, thus, pass through the filtration layers of nose hair and reach the end of the respiratory tract with the airflow and affect the air exchange mechanism in the lungs.

According to research, smoking one cigarette daily is equivalent to 22 µg/m³ of PM2.5. So the Delhi air, with an average of 350 µg/m³ of PM2.5 pollutants, is comparable to smoking at least 15 cigarettes daily. Therefore, you are reducing your life span by two and a half hours without touching a cigarette. On average, it adds up to nearly seven years in an average person’s lifespan of 70 years.  

Besides respiratory problems, inhaling PM2.5 pollutants can cause ailments like cancer and other cardiopulmonary problems. So pollution increases your medical expenses considerably. Therefore, environmental pollution can affect people’s mental and physical health.

Even short-term exposure to air pollution can cause lasting damage. Secondly, people who are already ill are more susceptible to respiratory diseases caused by air pollution. Children and older adults constitute the most vulnerable demographic.

The immediate after-effects of air pollution are eye irritation, headaches, fatigue, and anxiety. People also experience irritations in their noses and throat. PM2.5 is more dangerous than PM10 because it can enter the blood. Other significant ailments include damage to reproductive organs, the nervous system, the liver, and the spleen.

Diseases and Deaths – Delhi population

Air pollution can have adverse effects on human health. This infographic should put things into proper perspective.

COVID-19 has claimed a significant chunk of the population prematurely. In addition, Delhi air pollution is causing considerable dents to the Indian population by claiming an estimated 54,000 premature deaths in 2020. The corresponding figures for 2021 were approximately 57,000. With the pollution situation worsening in 2022, one can expect the casualties to rise further.

The initial effects are visible in the form of eye, nose, and throat irritation. The long-term after-effects of air pollution are respiratory diseases like asthma, pneumonia, bronchitis, a chronic obstructive pulmonary disorder, cardiac problems, lung cancer, and damage to the nervous system.

Generally, Delhi experiences air pollution throughout the year. However, the situation worsens at the start of the winter in October and continues till March. This period coincides with agriculture stubble burning, the marriage season, and Diwali.

One must admit that COVID has reduced our immunity levels considerably. Add air pollution to the mix, and you have a deadly combination. Studies indicate that children are growing with smaller lungs. Almost one in three children in Delhi has impaired lungs, leading to chances of pulmonary hemorrhage.

The healthy population also suffers from smog issues and a dip in air quality. Delhi has reported a surge in hospital patients with respiratory problems. The common complaints include chest and nasal congestion and coughing.      

Controversies involving Agriculture Stubble Burning

Many people attribute agricultural stubble burning as the prime reason for Delhi’s air pollution. Though it is not the most significant cause of air pollution, stubble burning does play an important role in polluting the environment. So let us see what stubble burning is and whether it can be avoided.

Agricultural stubble burning is a relatively recent practice, especially by farmers using mechanized harvesters. However, farmers in the states of Punjab, Haryana, Rajasthan, and Uttar Pradesh burn their wheat, rice, and sugarcane crop residue after every harvesting season before the start of the new agricultural season. The crop residue burning releases smoke that affects air quality.

The National Green Tribunal has banned burning crop residue (also known as parali) in these states. It is also an offense under Sec 188 of the Indian Penal Code and the Air and Pollution Control Act of 1981.

Despite the legislation, farmers continue to burn parali, with official reports stating that more than 500 million tonnes of crop residue are produced annually. While rice and wheat crops are the primary culprits, other crops include maize, millet, and sugarcane. Statistics show that Punjab burns more than 20 million tonnes of rice stubble annually.

Burning parali or crop residue brings health issues because the smoke pollutes the environment. The air in the winter months is heavy. Hence, the smoke does not rise above the atmosphere and circulates at low levels to pollute the air we breathe.

Studies show that burning crop residue releases toxic gases like CO₂ (149.24 million tonnes), CO (9 million tonnes), SO_x (0.25 million tonnes), and carbon (0.07 million tonnes). Besides, agricultural stubble burning releases 1.28 million tonnes of particulate matter. In addition to causing air pollution in Delhi and neighboring areas, agricultural stubble burning is the prime cause of the melting of Himalayan glaciers.

Modern-day agriculturists believe that stubble burning helps replenish the soil. But it does nothing of that sort because the heat generated by the fires elevates the soil temperature by nearly 10 degrees Celsius to kill bacteria and fungi that play a critical role in increasing soil fertility.

As stubble burning damages the microorganisms present in the soil, it affects their organic quality. Moreover, it invites enemy pests to destroy crops. In addition, stubble burning reduces the solubility capacity of the soil’s upper layers.

Indiscriminate crop residue burning reduces soil nutrients. Studies show that burning one ton of stubble results in a loss of 25 Kg of potassium, 5.5 Kg of nitrogen, 2.3 Kg of phosphorus, and 1 Kg of sulfur. We have already discussed the health effects of inhaling polluted air.

The stubble burning issue has generated various debates on air pollution, with politicians blaming each other. However, the Delhi Government has been vociferous in its opposition to stubble burning by Punjab and Haryana farmers.

So is there a solution to the stubble-burning problem? Yes, there is. Let us discuss the solutions to this issue that can go on to reduce air pollution in Delhi.

Stubble-burning Solutions

Should stubble be burnt to get rid of it? Surprisingly, the answer is NO. Stubble burning is a recent activity, especially after the introduction of mechanical harvesters. Farmers used stubble as cattle feed and compost manure in the olden days. It also has use for building house roofs in rural areas. Today, stubble has various benefits like generating biomass energy, manufacturing packing materials, paper, bioethanol, and other uses like industrial production and mushroom cultivation.

The Union Government has formulated a National Policy for the Management of Crop Residue to help enhance soil fertility and save up to Rs 2000 per hectare from manure costs.

Various agricultural machines are available to manage crop residues. Though these machines are expensive, the Union and the respective State Governments are providing subsidies for investing in crop residue management machinery.

These machines include

1. Baler – collect straw and make bales of paddy stubble
2. Reaper Binder – harvest paddy stubble and prepare bundles
3. Paddy Straw Chopper – cut paddy stubble and help integrate it with the soil
4. Happy Seeder – help sow seeds in standing stubble
5. Zero Till – prepare land for direct seed sowing in existing stubble
6. Rotavator – prepare the land and incorporate stubble in the soil   

These machines can help the farmer use stubble in various ways and not require them to take the easy way out by burning it. We have seen that burning stubble does not help the soil. Secondly, it causes multiple health problems.

Besides, medical costs can be substantial. For example, studies conducted by the (ISEC) Institute for Social and Economic Change estimate that the Punjab rural folk spend Rs 7.60 crores annually for treating stubble-burning-related ailments. 

Stubble-burning usually coincides with the change of the kharif to the rabi season. By this time, winter had advanced in the northern parts of India. The dip in the temperature levels causes temperature inversion to take place and results in enhanced air pollution. Indians celebrate Diwali during this period. The bursting of crackers affects the environment considerably and exacerbates air pollution. Let us discuss the after-effects of the Diwali celebration on air pollution in Delhi.

Issues Connected With Diwali

The primary causes of Delhi’s air pollution are vehicular emissions, industrial pollution, and agricultural stubble burning. However, Diwali celebrations also play a crucial role in worsening air quality in Delhi. Diwali usually coincides with the onset of winter and the burning of crop residue in the northern states. So, the pollutants emitted by bursting crackers linger in the atmosphere and exacerbate the problem to unmanageable levels.

The photograph above should explain it all. It was taken the morning after Diwali in Gurugram (near Delhi). See how polluted the environment is. Yes. We agree that Diwali is the most celebrated Indian festival. But can anyone deny that bursting crackers indiscriminately on Diwali adds to air pollution?

The following graph compares Delhi’s PM levels during Diwali for the last three years. Scrutiny shows that 2022 has been the best because of the least emissions. It may be due to greater awareness of the dangers that air pollution can have on human lives.

Bursting firecrackers during Diwali is enjoyable, and almost every Indian does it. But do you know the harmful chemicals that go into manufacturing these fireworks? Besides PM10 particles, bursting crackers release obnoxious gases like SO₂, NO₂, and O₃. Other toxic chemicals used in manufacturing include iron, lead, manganese, copper, nickel, and beryllium.

The CPCB has listed nearly 15 substances in fireworks and classified them as toxic. So, is banning the manufacture and bursting of crackers during Diwali the ideal solution to curb air pollution? Secondly, people travel often during Diwali to purchase new clothes and gifts for family and friends. Thus, they add to vehicular emissions and worsen the AQI further.

Many people advocate a ban on the use of crackers. Some states, like Delhi, have also enforced bans on bursting crackers, whereas others have assigned specific periods for the purpose. Though all Indians celebrate Diwali, it is usually considered a Hindu festival. Therefore, a blanket ban on crackers would not be acceptable to all.  

Nevertheless, pollution control is a state subject, and the respective state governments must take stringent steps to ensure their residents get clean and pure air to breathe. Let us see how the Delhi administration has tackled this contentious issue of air pollution in the capital.

How has the Delhi Administration tackled the problem?

Air pollution is nothing new for Delhi. The problems have been for more than three decades. The Delhi Administration has been fighting this contentious issue in various ways. Let us look at Delhi’s air pollution statistics since 2019 to understand the critical nature of the problem facing Delhi residents.

Statistics show that 2022 has been the worst year, with more days under the very poor and severe air quality categories.

Let us look at Delhi’s history or air pollution timeline to understand the situation better.

• The 1980s – The 80s saw a boom in vehicle sales in Delhi, leading to higher vehicle emission levels.
• 1996 – The Supreme Court of India took cognizance of Delhi’s air pollution and instructed the government to formulate an action plan.
• 2000 – A spurt in construction activities resulted in increased PM10 and PM2.5 pollutants. Besides, vehicles increased in Delhi at an annual growth rate of 10.75%.
• 2004 – The National Air Quality Index concept was introduced in 2004. It categorized air quality into six levels, a) good, b) satisfactory, c) moderate, d) poor, e) very poor, and f) severe or hazardous.
• 2016 – The Diwali season in 2016 was the worst experienced by the capital in history, with the AQI levels crossing 750 µg/m³. The entire city was under smog.
• 2017 – If the 2016 smog was terrible, the 2017 Great Smog was horrible, with PM10 levels touching 999 µg/m³. A cricket match was stopped due to pollution for the first time in history, with many players vomiting and showing signs of distress.
• 2019 – The Delhi government declared a public health emergency and closed schools and educational institutions in November.
• 2022 – The situation has worsened over the years.

Let us see the Delhi Administration’s history of responses to tackle air pollution.

The timeline shows that Delhi’s air pollution problems originated more than four decades ago, in the 1980s. However, the Supreme Court of India started hearing a PIL filed by noted environmentalist and lawyer M C Mehta in 1995. It indicated that vehicular and industrial emissions were the principal causes of air pollution.

So the Supreme Court ordered the closure of Delhi’s most polluting industries in a phased manner. It also ordered the relocation of brick kilns outside the city’s limits. The Delhi government submitted an action plan in response to the court’s order. It resulted in formulating the Environmental Pollution Control Authority of Delhi in 1998.

The Supreme Court acted on EPCA’s recommendations and ordered the conversion of Delhi’s public transport vehicles to CNG. It also ordered the phasing out of all pre-1990 autorickshaws. Other corrective measures included the removal of leaded petrol, phasing out 15 and 17-year commercial vehicles, and limiting the number of 2-stroke autorickshaws to 55000. In addition, coal-based power plants were converted to gas-based units.

The Delhi Government revised the National Ambient Air Quality Standards (NAAQS) in 2009 to add 12 more pollutants, including PM2.5. While WHO prescribed acceptable levels of 5 µg/m³ for PM2.5 and 15 µg/m³ for PM10 contaminants, the NAAQS stipulated 40 µg/m³ and 60 µg/m³ for PM2.5 and PM10, respectively.

A US-based Health Effects Institute published a report stating that Delhi was the most polluted city in the world between 2010 and 2019, with an average annual exposure of 110 µg/m³ PM2.5.

2016 saw the Delhi government try out an innovative scheme of odd-even vehicle rationing in January and April. That winter saw Delhi experiencing the worst smog in history, with PM2.5 and PM10 levels reaching an unprecedented high of 999 µg/m³.

The Ministry of Environment and Forests (presently the Ministry of Environment, Forests, and Climate Change MEFCC) introduced a Graded Response Action Plan in 2017, involving close coordination between various agencies to tackle Delhi’s air pollution issues.

Studies conducted by IIT Delhi, IIT Madras, and Delhi Pollution Control Committee showed that vehicular emissions, rapid industrialization, the spread of urban areas, and the increasing population were responsible for the high pollution levels. The population grew from 13.78 million in 2001 to 16.78 million in 2011 and further to more than 20 million in 2019. As a result, vehicles increased to 10.9 million by March 2018.

Besides, the CPCB found that most of Delhi’s small and medium industries in the polluting clusters do not meet stipulated standards for air, water, and soil pollution. The number of such industries was more than 3100 spread over the NCR. As a result, PM2.5 pollutants were the single most contributor to Delhi’s air pollution. The following statistical presentation explains it the best.

However, did the remedial measures initiated by the Delhi government yield the desired results?

• The conversion from petrol and diesel to CNG was not entirely successful because it reduced SPM and PM10 levels but increased carbon monoxide levels.
• The cap of 55000 autorickshaws was not revised until 2011. In the meantime, four-stroke engines and CNG were introduced. But the autorickshaw sector could not grow, leading to the black marketing of auto permits.
• While the Delhi human population grew by 45% between 1997 and 2011, the vehicular population grew by 250%. Besides, Delhi’s public transport is inadequate. Compared to Delhi, Paris has an extensive metro system, even though Paris is smaller than Delhi.
• The odd-even vehicle number rule flopped miserably because the principal culprits, the heavyweight vehicles, were exempted from this ruling.
• Delhi has an inadequately equipped waste management system. While the daily waste generation is over 10000 tons, the landfills can hold not more than 6000 tons. As a result, it leads to the burning of waste and exacerbates the pollution problem.
• Studies show that a significant proportion of polluting sources are present throughout the year. But the situation worsens in winter because of low temperatures.
• Farm stubble burning is a seasonal issue. While the principal contributors are farmers from neighboring states, it has become more of a political challenge than a problem concerning Delhi residents.

The Political Slugfest – Does it do any good?

The Delhi Government has always played the blame game when dealing with farm stubble burning. The present AAP-led government did not leave any stone unturned in blaming the neighboring states, like Punjab, Haryana, Uttar Pradesh, and Rajasthan.

The AAP government led by Arvind Kejriwal has always been renowned for its theatrics and blame-shifting capabilities. For example, it blamed agricultural stubble burning as the most significant issue causing air pollution in Delhi. However, the blame lies elsewhere, as discussed in this article.

Source – https://indianexpress.com/article/india/punjab-delhi-haryana-up-action-plan-stubble-burning-air-pollution-7528596/

The blame game continued as long as the neighboring states were governed by parties other than the AAP. However, Punjab has an AAP government today. Moreover, recent interviews and press conferences by Arvind Kejriwal concerning farm stubble show the AAP Delhi government taking a soft stance towards Punjab while blaming the other states.

Today, the Delhi government talks of remedial measures and suggests alternative uses of crop residue as its invention. But these measures have already been suggested in the past. However, only some farmers have adopted them. Therefore, the results are not visible. The need of the times is for all farmers to adopt these solutions and stop farm stubble burning completely. The political slugfest is not doing any good to anyone.

Nevertheless, farm stubble burning is not the only issue. As a result, the government can take more steps to bring Delhi’s air pollution levels under control.

How can the problem be resolved? – Steps Government should take

Air pollution does not know or recognize state boundaries. Hence, governments should exhibit a strong political will and employ the best technologies to tackle the problem. The Delhi government has initiated several measures, but more needs to be done.

Outdoor Air Purifiers

If you have traveled across the length and breadth of Delhi, you must have noticed huge refrigerator-sized machines placed at some of the busiest traffic intersections. These outdoor air purifiers suck in the pollutants emitted by vehicles and pump fresh air.

The CPCB has cleared the installation of 54 such machines across Delhi. Each machine costs nearly Rs 2.60 crores.

These air-purifying machines comprise three filters to trap particulate matter and dust. They also contain UV lamps that trigger photocatalyst-coated charcoal particles to oxidize and transform the VOCs that pass through the filters into carbon dioxide and water. The machines working currently can purify air over a 500 square meter area. Larger and more powerful devices capable of purifying areas up to 10000 square meters are in the pipeline.

However, are these machines useful? That is a million-dollar question because each machine costs around $370,000. Furthermore, can these machines be efficient in an outdoor environment? The Center for Science and Environment has expressed its doubts over the machine’s efficacy. They contend that the devices can work efficiently in a lab-controlled environment but not outdoors. The impact area is approximately 2 to 3 square meters around the machine.

Even assuming the machines are efficient, the pollutants they remove are minuscule compared to the haze enveloping Delhi. The World Health Organization has rated Delhi the most polluted of the large cities worldwide. The problem can only worsen, especially as the UN predicts Delhi to become the world’s largest city by 2028.

Portable Air Filters and other innovative technologies

The CPCB has tried an innovative technique to curb air pollution by installing small air filters atop public buses. Around 30 buses come with these filters that can trap pollutants while on the move and provide some respite. But, it is like a drop in the ocean. More work is necessary in this regard.

The CPCB plans to treat construction-related pollution by sprinkling magnesium chloride and cement on roads and construction installations. They believe that these hygroscopic materials absorb moisture from the air and make the ground wet to prevent dust from flying in the air. Similarly, the agency announced a cloud seeding project to create artificial rain and wash away pollution.

One can classify these attempts as Band-Aid solutions. How can they be effective when there is enormous scale pollution? Delhi should look at other cities like Mexico City, Los Angeles, Cairo, and Beijing and study how they faced the challenges of air population. One has to concede that Delhi has a massive population. Therefore, the solutions are never going to be easy. However, they require a strong political will and not publicity stunts that the government is presently engaging in.

Here are some steps the government can take to reduce air pollution.

• Stop stubble burning – Stubble burning is an external problem, but it affects Delhi air more than anything else. So, the respective governments to sit together and formulate alternate measures rather than blaming each other.
• Proper waste management – The Delhi government must improve its waste management technology and not rely on burning waste. One solution is to shift the landfill areas outside the city limits and set up waste management plants to convert waste into farm manure. Waste can also be converted to energy and alternate biofuel for vehicles.
• Encourage clean fuel like CNG or electric vehicles – CNG is a purer option than standard fuel like petrol and diesel. The Delhi government has already mandated public transport vehicles to use CNG. The thrust should now be on private and commercial transport vehicles. Electric cars are also an excellent option. But there is a lot to do on the infrastructure front. Besides, BSVI norms should become mandatory for all vehicles, and all existing vehicles with BSIV engines should be phased out gradually.
• Promote environmentally friendly products – Almost every home has refrigerators and air conditioners. Unfortunately, these appliances emit volatile organic compounds that can pollute the environment. So, the government should encourage people to use environmentally-friendly products and help the government in controlling air pollution.

The 15-point Winter Action Plan formulated by the Delhi Government.

The Delhi Government has formulated a 15-point Winter Action Plan to control air pollution. However, it requires active cooperation from the public.

• Bio-decomposer for farm stubble – The PUSA Institute has developed a liquid bio-decomposer that can deal with farm stubble without burning them. This year, the government has distributed this bio-decomposer free to farmers to decompose farm residue and cover around 4000 acres. It has plans to provide such machines to more farmers and cover up to 5000 acres in the following action plan.
• Garbage burning and cracker ban – Garbage disposal by burning them is a crucial pollution source. So, the government has banned its burning and formed 611 crack teams to identify instances of garbage burning. Similarly, 210 units are working to catch offenders bursting firecrackers, contributing to air pollution. This ban will continue till January 2023.
• Monitoring construction sites – The government has mandated that anyone constructing buildings with an area of more than 5000 square feet should register on the web portal and use anti-smog guns to monitor dust control on a real-time basis. Nearly 586 teams are monitoring these activities.
• Use of anti-smog guns – The Delhi government has plans to install 233 anti-smog guns and 150 mobile anti-smog guns across the city to combat pollution.
• Use of sweeping machines – The Delhi government has employed nearly 80 road sweeping machines. Besides, 521 water-sprinkling machines are put in force to sprinkle water and prevent dust from flying into the air.
• Route Diversions – The government has identified 203 busy traffic routes and is preparing alternate routes to prevent traffic congestion and reduce vehicular emissions.
• Green Room and scientific monitoring – The government has partnered with IIT Kanpur to set up a green room to monitor pollution control measures. This facility has nine scientific experts monitoring air quality across Delhi in real time.
• Process e-waste – A 20-acre e-waste park is being set up to process electronic waste in the city.
• Hotspot supervision – The government has identified 13 hotspots where it will strictly supervise air pollution control measures.
• Paryavaran Mitras – Nearly 3500 volunteers have enrolled as Paryavaran Mitras to create awareness of air pollution and help the government tackle the issue. Anyone can become a Paryavaran Mitra by dialing a missed call to 8448441758.
• Enhance Green Cover – Planting trees is the best way to increase green cover over Delhi. Unfortunately, rampant deforestation and cutting down trees to facilitate infrastructure development have taken a heavy toll. So, the government plans to reverse the process by aiming to plant 42 lakh trees across the capital.
• Green Delhi App – The government has launched a new mobile app, Green Delhi App, where residents can raise complaints regarding pollution. The government states that nearly 53000 complaints have been lodged, with a high resolution rate of 90%.
• PUC Certificates for vehicles – Petrol vehicles older than 15 years and diesel automobiles over 10 years old are mandated to hold PUC certificates. The government has formed 380 teams to ensure strict enforcement.
• GRAP (Graded Response Action Plan) – The government plans to upgrade this plan already floated by them last year. This plan envisages forecasting deterioration of air quality at least three days in advance.
• Cooperate with neighboring NCR cities – Active cooperation is necessary between the Delhi government and the neighboring states to ensure the successful implementation of the 15-point Action Plan. It concerns providing 24×7 electricity to all neighboring cities like Gurugram (industrial hub) to eliminate the use of diesel generators.     

While the government is doing its best to control air pollution, residents also have a crucial role to play. So let us now discuss the steps people can take to reduce air pollution and get relief.

The Present Situation – Steps people can take to get relief

The government does what it has to do to resolve air pollution issues. But people should play their role in supplementing the Delhi Administration’s efforts. Let us discuss some steps that people should take to get relief from air pollution issues.

• Use Air Purifiers – Air purifiers are the best appliances in indoor areas like homes, offices, restaurants, cinema halls, etc. These appliances are available at reasonable prices. So, a family can have one air purifier for every room, especially when children and older adults are present in their homes. These appliances provide pure air and protect you from the effects of inhaling polluted air.
• Reduce unnecessary travel – The best way to protect oneself from air pollution is to avoid going out of the house unnecessarily. Reducing unnecessary travel can result in fewer vehicular emissions to benefit society. Single individuals need not go around in their cars. Using public transport is a better idea.
• Use environmentally friendly appliances – People should use ecologically friendly appliances at home that reduce ozone pollution. For example, while air conditioners and refrigerators are essential during summer, keeping your home’s windows open and allowing fresh air circulation is better.
• Wear masks whenever you go out – COVID-19 has already forced people to wear face masks whenever they step out of the house. So, continuing this practice to prevent inhaling polluted air should not be a problem. It is advisable to use N95 and N99 masks because they can prevent PM2.5 particles from entering your respiratory system. However, it should be worn snugly and cover the entire nose and mouth.
• Avoid strenuous exercises – While walking and jogging are excellent exercises to keep you healthy, they do not serve any purpose if you inhale the polluted air. Therefore, it is better to avoid strenuous activities. Besides, people tend to feel breathless when exercising, forcing them to breathe through their mouths. That can be dangerous because it allows more significant contaminants to enter the system easily.
• Plant air-purifying plants indoors – Plants like Ivy, Spider Plants, and Aloe Vera have air-purifying properties. So, having these plants in homes and offices can purify the indoor air. The best feature is that these are low-maintenance plants because they do not require frequent watering or adequate oxygen.
• Take frequent steam baths – Steam baths can help open the skin pores and allow them to breathe easily. It helps relax airways and helps the body eliminate hazardous substances through sweat and mucus. You can add a couple of drops of eucalyptus oil to a jug of boiling water and inhale the steam. It helps open up the lungs and clears the nasal passage blocks.
• Consume healthy food – One should take care of their health to develop immunity levels that can help them fight diseases caused by inhaling polluted air. So, a healthy diet comprising Vitamin C-rich fruits, omega-rich foods, and magnesium-rich foods is essential. Vegetables like carrots, radishes, sweet potatoes, and spinach are excellent sources of Vitamin A. Oranges, sweet limes, and lemons are rich sources of Vitamin C, whereas bran oil and almonds contain Vitamin E.
• Monitor air quality Index – The Delhi government has launched its Green App. Besides, the AQI app is also available for free on PlayStore and AppStore. So every Delhi resident should have these apps on their smartphones to enable them to monitor air pollution levels in the city. So they can avoid heavy traffic congestion and places where the air quality is hazardous.
• Use environmentally free personal care products – Your perfumes can contain pollutants that can emit VOCs and harm the environment. So it is advisable to use good quality products that do not pollute the atmosphere and worsen the air quality.
• Ventilate your homes adequately – The air quality is not always unfavorable throughout the day. Your smartphone app alerts you in this regard. So you can ventilate your homes accordingly to let in as much fresh air as possible. Proper air circulation allows you to inhale healthy air.

We have discussed steps individuals can take to control air pollution. The government is also playing its part. But there is much to learn from the mistakes of others. For example, Delhi was not always top of the list of highly polluted cities. There was a time when Beijing used to top the list. However, the situation has improved, and is considered a much cleaner city today. So, Delhi can learn from Beijing and resolve some of its air pollution problems.

Lessons Delhi can learn from China.

Beijing was once counted among the highly polluted cities in the world. The air quality was so bad that it caused a health crisis, killing nearly one million people annually. However, today, Beijing has dropped out of the world’s first 200 most polluted cities. Delhi can benefit from the Beijing experience and improve its air quality. Let us see what Beijing did to come out of the crisis.

The Chinese government shut down coal-fired power plants in the main cities to reduce pollution. Cities like Shanghai, Beijing, and Shenzhen restricted cars on the streets and introduced electric buses. In addition, the country shut down its coal mines and reduced its iron and steel-making capacities.

The government encouraged afforestation and planted over 35 billion trees across 12 provinces. In addition, they earmarked a massive budget for reforestation programs and followed them up vigorously to ensure adequate tree planting and increase the green cover.

China released its Air Pollution Action Plan in 2013 to reduce its PM2.5 levels by 33% in Beijing. It also took up river-cleaning attempts to succeed in its endeavor. Delhi can follow suit by cleaning up the Yamuna and preventing industrial and human waste disposal.

On achieving the Air Pollution Action Plan, China introduced its Three-Year Plan for Winning the Blue Sky War in 2018. It mandated a minimum of 18% reduction in PM2.5 levels to bring it to par with international standards.

The first action plan did not address the problem of surface-level ozone. However, we have seen that surface-level ozone is a critical cause of air pollution in Delhi, which is responsible for the higher number of asthma and chronic obstructive pulmonary disorder cases. Therefore, the new action plan focused on eliminating surface-level ozone and reducing VOC and nitrogen oxide levels to meet international standards.

COVID-19 helped China achieve its objectives by implementing strict lockdowns and clamping down on offenders. As a result, the decrease in industrial activities helped considerably reduce greenhouse gas emissions and improve air quality.

As a result of the strict measures taken by China to address its air pollution problems, the life expectancy of the average Chinese resident has increased by 2.4 years.

Delhi can learn lessons from China and other countries that have combated air pollution. Though it will take time for the Delhi air quality to reach ISO standards, it must start soon. So let us now understand what the ISO standards on air quality are.

ISO Standards on Air Quality

We have discussed much about Delhi’s poor air quality and the harm it causes to life and the environment. But do you know that 91% of the world’s population lives in places that do not meet international standards or WHO limits? So, what are the international standards? Let us discuss them here.

The World Health Organization stipulated the following Air Quality Guideline levels in 2005 and improved them in 2021.

Pollutant	Averaging Time	2005 Guidelines	2021 Guidelines
PM2.5 µg/m3	Annual	10	5
	24-hour	25	15
PM10 µg/m3	Annual	20	15
	24-hour	50	45
O3 µg/m3	Peak Season	–	60
	8-hor	100	100
NO2 µg/m3	Annual	40	10
	24-hour	–	25
SO2 µg/m3	24-hour	20	40
CO2 µg/m3	24-hour	–	4

Source – https://www.who.int/news-room/feature-stories/detail/what-are-the-who-air-quality-guidelines

AQI Standards

While it is presently impossible for Indian cities to achieve WHO standards, we can at least try to come close to AQI standards. AQI has stipulated the following standards to decide the air quality.

AQI Range	Health Impact	PM10 24h µg/m3	PM2.5 24h µg/m3	SO2 24h µg/m3	NO2 24h µg/m3	O3 8h µg/m3	CO 8h mg/m3	NH3 24h µg/m3
Good (0 to 50)	Minimal impact	0 – 50	0 – 30	0 – 40	0 – 40	0 – 50	0 – 1	0 – 200
Satisfactory (51 – 100)	Minor discomfort for sensitive people	51 – 100	31 – 60	41 – 80	41 – 80	51 – 100	1.1 – 2	201 – 400
Moderately Polluted (101 – 200)	Breathing discomfort to people with lung problems	101 – 250	61 – 90	81 – 380	81 – 180	101- 168	2.1 – 10	401 – 800
Poor (201 – 300)	Breathing discomfort to people on prolonged exposure	251 – 350	91 – 120	381 – 800	181 – 280	169 – 208	10 – 17	801 – 1200
Very Poor (301 – 400)	Respiratory illness in people on prolonged exposure	351 – 430	121 – 250	801 – 1600	281 – 400	209 – 748	17 – 34	1200 – 1800
Severe (401 – 500)	Respiratory illness in people on prolonged exposure	>430	>250	>1600	>400	>748	>34	>1800

Source – AQI

Delhi vs Other Indian cities

We have discussed Delhi’s air pollution in detail. But do you know how other Indian cities fare compared to Delhi? Let us compare the real-time figures of India’s top ten polluted cities on December 03, 2022.

AQI is India’s most reliable source for data concerning air pollution and air quality index. Here are the top ten highly polluted cities in India presently.

• Patna – 219
• New Delhi – 212
• Sonepat – 204
• Uran – 202
• Gaya – 200
• Nagpur – 200
• Hissar – 196
• Rajgir – 194
• Deo – 193
• Faridabad – 191

Similarly, let us also look at the ten least polluted cities in India today.

• Aizawl – 12
• Kilkunda – 17
• Rameswaram – 19
• Sopur – 21
• Tuticorin – 24
• Coimbatore – 24
• Kodaikanal – 25
• Channarayapatna – 25
• Kulu – 29
• Manali – 29

Major Air Pollutants in Delhi – Real-time data – December 03, 2022

• PM2.5 – 161
• PM10 – 246
• SO₂ – 3
• CO – 675
• O₃ – 36
• NO₂ – 23

Currently, the PM2.5 concentration in Delhi is 10.7 times above the WHO recommended limits.

Frequently Asked Questions – Delhi Air Pollution

Conclusion

Delhi is a virtual gas chamber today because of the city’s hazardous air pollution levels. It is almost impossible for Delhi residents and visitors to get around with their regular work without inhaling unhealthy contaminants.

Virtually every individual in Delhi has some physical ailment. Children and elderly people are the most vulnerable. So, it requires a lot of firefighting for the government to clean up Delhi’s air.

Residents must also pitch in with their concerted efforts in their own interests. However, nothing is impossible because cities with worse track records than Delhi have solved their air pollution problems. In this research article, we have discussed all aspects of Delhi air pollution, its causes and effects, and the possible solutions to the problem.