Air Pollution



 Pollution is defined as the addition or exessive addition of certain materials to the physical environment thereby making it less fit or unfit for living. These materials are called pollutants

Air pollution is the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types of air pollutants, such as gases (such as ammonia, carbon monoxide, sulfur dioxide, nitrous oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both organic and inorganic), and biological molecules.

Air pollution may cause diseases, allergies and even death to humans; it may also cause harm to other living organisms such as animals and food crops, and may damage the natural environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for example, acid rain). Both human activity and natural processes can generate air pollution.

 Productivity losses and degraded quality of life caused by air pollution are estimated to cost the world economy $5 trillion per year.

Various pollution control technologies and strategies are available to reduce air pollution.

To reduce the impacts of air pollution, both international and national legislation and regulation have been implemented to regulate air pollution.

Local laws where well enforced in cities have led to strong public health improvements. At the international level some of these efforts have been successful, for example the Montreal Protocol which successful at reducing release of harmful ozone depleting chemicals or 1985 Helsinki Protocol which reduced sulfur emissions, while other attempts have been less rapid in implementation, such as international action on climate change.


Pollutants emitted into the atmosphere by human activity include:

  • Carbon dioxide (CO2) – Because of its role as a greenhouse gas it has been described as “the leading pollutant” and “the worst climate pollutant”. Carbon dioxide is a natural component of the atmosphere, essential for plant life and given off by the human respiratory system.

CO2 currently forms about 410 parts per million (ppm) of earth’s atmosphere, compared to about 280 ppm in pre-industrial times, and billions of metric tons of CO2 are emitted annually by burning of fossil fuels.

  • Sulfur oxides (SOx) – particularly sulfur dioxide, a chemical compound with the formula SO2. SO2 is produced by volcanoes and in various industrial processes. Coal and petroleum often contain sulfur compounds, and their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain is formed. This is one of the causes for concern over the environmental impact of the use of these fuels as power sources.
  • Nitrogen oxides (NOx) – Nitrogen oxides, particularly nitrogen dioxide, are expelled from high temperature combustion, and are also produced during thunderstorms by electric discharge. They can be seen as a brown haze dome above or a plume downwind of cities. Nitrogen dioxide is a chemical compound with the formula NO2. It is one of several nitrogen oxides. One of the most prominent air pollutants, this reddish-brown toxic gas has a characteristic sharp, biting odor.
  • Particulate matter / particles, alternatively referred to as particulate matter (PM), atmospheric particulate matter, or fine particles, are tiny particles of solid or liquid suspended in a gas.

In contrast, aerosol refers to combined particles and gas. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of aerosols.

Averaged worldwide, anthropogenic aerosols—those made by human activities—currently account for approximately 10 percent of our atmosphere. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer. Particulates are related to respiratory infections and can be particularly harmful to those already suffering from conditions like asthma.

  • Chlorofluorocarbons (CFCs) – harmful to the ozone layer; emitted from products are currently banned from use. These are gases which are released from air conditioners, refrigerators, aerosol sprays, etc. On release into the air, CFCs rise to the stratosphere. Here they come in contact with other gases and damage the ozone layer. This allows harmful ultraviolet rays to reach the earth’s surface. This can lead to skin cancer, eye disease and can even cause damage to plants.
  • Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere. It is also an important constituent of certain regions of the stratosphere commonly known as the Ozone layer. Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night. At abnormally high concentrations brought about by human activities (largely the combustion of fossil fuel), it is a pollutant and a constituent of smog.


  • Burning of Fossil Fuels: Most of the pollutants are produced by burning fossil fuels or wood, for driving, heating, power plants and industry.
    • Several man-made factors, vehicular emissions, construction dust, garbage burning causes severe pollution.
    • The particles can be made of black carbon, nitrates, sulphates, ammonia or mineral dust.
  • Agriculture & Allied Sources: Farming is one such source of pollution, with ammonia from livestock manure and fertilisers blowing into cities and forming particles, particularly in spring time when crops are sown and muck is spread.
    • Further, stubble burning is also one of the major sources of air pollution in northern India, especially in winters.
  • Natural Sources: Apart from it, there are some natural sources of outdoor air pollution such as dust storms.
  • There are thermal power plants around Delhi and the polluted air moves towards the neighbouring cities. Many industries are using high sulphur oil which is highly polluted. There are large mounds of solid waste Seasonally farmers of Punjab and Haryana burn their crop residues for preparing their fields for next crop and during the winter the air becomes heavy, there is temperature inversion and the dispersal of the pollutants is very low. During winter we also see people burning fire during night to bear the cold. All this put together has a cumulative effect on the air quality.
  • Fumes from paint, hair spray, varnish, aerosol sprays and other solvents. These can be substantial; emissions from these sources was estimated to account for almost half of pollution from volatile organic compounds in the Los Angeles basin in the 2010s
  • Waste deposition in landfills, which generate methane. Methane is highly flammable and may form explosive mixtures with air. Methane is also an asphyxiant and may displace oxygen in an enclosed space. Asphyxia or suffocation may result if the oxygen concentration is reduced to below 19.5% by displacement.


Indoor Air Pollution

Air pollution is usually thought of as smoke from large factories or exhaust from vehicles. But there are many types of indoor air pollution as well.

Heating a house by burning substances such as kerosene, wood, and coal can contaminate the air inside the house. Ash and smoke make breathing difficult, and they can stick to walls, food, and clothing.

Naturally-occurring radon gas, a cancer-causing material, can also build up in homes. Radon is released through the surface of the Earth. Inexpensive systems installed by professionals can reduce radon levels.

Some construction materials, including insulation, are also dangerous to people’s health. In addition, ventilation, or air movement, in homes and rooms can lead to the spread of toxic mold. A single colony of mold may exist in a damp, cool place in a house, such as between walls. The mold’s spores enter the air and spread throughout the house. People can become sick from breathing in the spores.

Effects of Air Pollution On The Environment

Like people, animals, and plants, entire ecosystems can suffer effects from air pollution. Haze, like smog, is a visible type of air pollution that obscures shapes and colors. Hazy air pollution can even muffle sounds.

Air pollution particles eventually fall back to Earth. Air pollution can directly contaminate the surface of bodies of water and soil. This can kill crops or reduce their yield. It can kill young trees and other plants.

Sulfur dioxide and nitrogen oxide particles in the air, can create acid rain when they mix with water and oxygen in the atmosphere. These air pollutants come mostly from coal-fired power plants and motor vehicles. When acid rain falls to Earth, it damages plants by changing soil composition; degrades water quality in rivers, lakes and streams; damages crops; and can cause buildings and monuments to decay.

Like humans, animals can suffer health effects from exposure to air pollution. Birth defects, diseases, and lower reproductive rates have all been attributed to air pollution.


Global Warming

Global warming is an environmental phenomenon caused by natural and anthropogenic air pollution. It refers to rising air and ocean temperatures around the world. This temperature rise is at least partially caused by an increase in the amount of greenhouse gases in the atmosphere. Greenhouse gases trap heat energy in the Earths atmosphere. (Usually, more of Earths heat escapes into space.)

Carbon dioxide is a greenhouse gas that has had the biggest effect on global warming. Carbon dioxide is emitted into the atmosphere by burning fossil fuels (coal, gasoline, and natural gas). Humans have come to rely on fossil fuels to power cars and planes, heat homes, and run factories. Doing these things pollutes the air with carbon dioxide.

Other greenhouse gases emitted by natural and artificial sources also include methane, nitrous oxide, and fluorinated gases. Methane is a major emission from coal plants and agricultural processes. Nitrous oxide is a common emission from industrial factories, agriculture, and the burning of fossil fuels in cars. Fluorinated gases, such as hydrofluorocarbons, are emitted by industry. Fluorinated gases are often used instead of gases such as chlorofluorocarbons (CFCs). CFCs have been outlawed in many places because they deplete the ozone layer.

Worldwide, many countries have taken steps to reduce or limit greenhouse gas emissions to combat global warming. The Kyoto Protocol, first adopted in Kyoto, Japan, in 1997, is an agreement between 183 countries that they will work to reduce their carbon dioxide emissions. The United States has not signed that treaty.


Pollutants Causing Effect on Health

  • Pollutants with the strongest evidence for public health concern include particulate matter (PM), Ozone (O3), Nitrogen dioxide (NO2) and Sulphur dioxide (SO2).
  • These pollutants are capable of penetrating deep into lung passageways and entering the bloodstream causing cardiovascular, cerebrovascular and respiratory impacts.


  • State of Global Air 2020 Report: According to it, India faced the highest per capita pollution exposure (83.2 μg/cubic metre) in the world.
    • In 2020, over 116,000 infants in India died within a month after birth due to exposure to severe air pollution.
    • The report also suggests exposure to polluted air during pregnancy is linked to low weight and premature birth.
    • Further, it noted that long-term exposure to outdoor and household air pollution contributed to over 1.67 million annual deaths from stroke, heart attack, diabetes, lung cancer, chronic lung diseases, and neonatal diseases in India in 2019.
  • WHO: According to WHO, toxic air is now the biggest environmental risk of early death, responsible for one in nine of all fatalities.
    • It kills 7 million people a year, far more than HIV, tuberculosis and malaria combined,
    • An estimated 4.2 million premature deaths globally are linked to ambient air pollution, mainly from heart disease, stroke, chronic obstructive pulmonary disease, lung cancer, and acute respiratory infections in children.
  • World Bank: According to a 2019 World Bank report, the lost lives and ill health caused are also a colossal economic burden:
    • $225bn is lost labour income in 2013, or $5.11tn per year (about $1m a minute), if welfare losses are also added.


The following items are commonly used as pollution control devices in industry and transportation. They can either destroy contaminants or remove them from an exhaust stream before it is emitted into the atmosphere.

Particulate control

  • Mechanical collectors (dust cyclones, multicyclones)
  • Electrostatic precipitators An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air), using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulates such as dust and smoke from the air stream.
  • Particulate scrubbers Wet scrubber is a form of pollution control technology. The term describes a variety of devices that use pollutants from a furnace flue gas or from other gas streams. In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid, by forcing it through a pool of liquid, or by some other contact method, so as to remove the pollutants.
  • NOx control
    • Low NOx burners
    • Selective catalytic reduction (SCR)
    • Selective non-catalytic reduction (SNCR)
    • NOx scrubbers
    • Exhaust gas recirculation
    • Catalytic converter (also for VOC control)
  • VOC abatement
    • Adsorption systems, using activated carbon, such as Fluidized Bed Concentrator
    • Flares
    • Thermal oxidizers
    • Catalytic converters
    • Biofilters
    • Absorption (scrubbing)
    • Cryogenic condensers
    • Vapor recovery systems
  • Acid Gas/SO2 control
    • Wet scrubbers
    • Dry scrubbers
    • Flue-gas desulfurization




In addition to the international Kyoto Protocol, most developed nations have adopted laws to regulate emissions and reduce air pollution. In the United States, debate is under way about a system called cap and trade to limit emissions. This system would cap, or place a limit, on the amount of pollution a company is allowed. Companies that exceeded their cap would have to pay. Companies that polluted less than their cap could trade or sell their remaining pollution allowance to other companies. Cap and trade would essentially pay companies to limit pollution.

In 2006 the World Health Organization issued new Air Quality Guidelines. The WHOs guidelines are tougher than most individual countries existing guidelines. The WHO guidelines aim to reduce air pollution-related deaths by 15 percent a year.

Consequences of Air Pollution:

  • Large number of deaths (around 2000) is attributed due to pollution which is very frightening. The figures may not be correct because they are only estimates. To find out precise data it requires a serious investigation for which neither the man power is available nor are the time and resources available. Therefore we need to take a precautionary approach towards tackling pollution.
  • India has recorded 50% increase in the pre mature deaths linked to PM 2.5 and this is between 1990 and 2015 almost coinciding with the economic liberalisation.
  • Air quality has become a serious health issue because the pollutants entre deep inside the lungs and the lungs capacity to purify bloods gets reduced which affects the person’s growth, mental ability and the working capacity especially for children, pregnant women and elderly people.
  • Poor people are more vulnerable to air pollution because they are the one who spend more time on roads.

Measures to improve air quality:

  • Improving public transport
  • Limiting the number of polluting vehicles on the road
  • Introducing less polluting fuel
  • Strict emission regulations
  • Improved efficiency for thermal power plants and industries
  • Moving from diesel generators to rooftop solar
  • Increased use of clean renewable energy
  • Electric vehicles
  • Removing dust from roads
  • Regulating construction activities
  • Stopping biomass burning, etc.

What is the National Air Quality Index?

Launched in 2014 with outline ‘One Number – One Color -One Description’ for the common man to judge the air quality within his vicinity.

The measurement of air quality is based on eight pollutants, namely: Particulate Matter (PM10), Particulate Matter (PM2.5), Nitrogen Dioxide (NO2), Sulphur Dioxide (SO2), Carbon Monoxide (CO), Ozone (O3), Ammonia (NH3), and Lead (Pb).

AQI has six categories of air quality. These are: Good, Satisfactory, Moderately Polluted, Poor, Very Poor and Severe.

It has been developed by the CPCB in consultation with IIT-Kanpur and an expert group comprising medical and air-quality professionals.


Way Forward

  • WHO’s 4 Pillar Strategy: WHO adopted a resolution (2015) to address the adverse health effects of air pollution. There is a need to adhere to a roadmap highlighted under this. This 4-pillar strategy calls for an enhanced global response to the adverse health effects of air pollution. Those four pillars are:
    • Expanding the knowledge base
    • Monitoring and reporting
    • Global leadership and coordination
    • Institutional capacity strengthening
  • Proactive Measure: Interventions like pollution-monitoring apps should be promoted, so that people can choose to avoid the travelling worst times, and take alternative city walking routes that keep people away from the most polluted areas. The application of Graded Response Action Plan in the Delhi-National Capital Region (NCR) is a step in the right direction.
  • Innovative Measure: There is a need to adopt innovative solutions for in-situ treatment of pollution. For example, the Delhi government is also experimenting with a new organic way of decomposing stubble with Indian Agriculture Research Institute’s “Pusa decomposer”.
  • Responsibility of Citizens: Despite plenty of ideas and solutions to tackle air pollution, still conditions remain the same. This is due to the lack of serious political will and people’s participation. Therefore, citizens should continue to stand up for their right to healthy and sustainable environments and hold governments accountable.
  • Addressing Injustice: There are huge injustices at the heart of the air pollution problem as the Poorer people are also most exposed to air pollution. Thereby, the need to enforce Polluter Pay principle and an environment tax must be levied from industries of polluting in nature.


Fighting air pollution is a public issue and subsequently an everybody’s responsibility. Therefore, the need is for concerted and coordinated efforts with active involvement of all the stakeholders. This should include the Government (national, state and local governments), cities, community at large and individuals.

Further, there is a need for policy which envisages a healthy energy transition and healthy urban planning transition.



Key Points

  • Causes of Deteriorating Air Quality:
    • Delhi’s air typically worsens in October-November and improves by March-April. Current weather conditions are not unfavourable, unlike in winter. During winter, cool and calm weather traps and spikes daily pollution, particularly in north Indian cities located in the Indo Gangetic Plain.
    • Hence, apart from local emissions, the deterioration in air quality is being attributed to an increase in fire counts, mostly due to burning of wheat crop stubble in northern India.
    • The most crucial reasons for the alarming levels of air pollution in Delhi include:
      • City’s landlocked geographical location.
      • Crop burning in neighbouring states (Punjab, Haryana and Rajasthan).
      • Vehicular emissions.
      • Industrial pollution.
      • Large-scale construction activities.

Air Pollution in Delhi

  • Air pollution in Delhi-NCR and the Indo Gangetic Plains is a complex phenomenon that is dependent on a variety of factors.

Change in Wind Direction:

  • October usually marks the withdrawal of monsoons in Northwest India and during this time, the predominant direction of winds is northwesterly.
  • The direction of the wind is northwesterly in summers as well, which brings the dust from northern Pakistan and Afghanistan.

Reduced Wind Speed:

  • High-speed winds are very effective at dispersing pollutants, but winters bring a dip in wind speed overall as compared to in summers which makes the region prone to pollution.
  • Also, Delhi lies in a landlocked region which does not have a geographical advantage that eastern, western or southern parts of the country enjoy where the sea breeze disperses the concentrated pollutants.

Stubble Burning:

  • Stubble burning in Punjab, Rajasthan and Haryana is blamed for causing a thick blanket of smog in Delhi during winters. It emits large amounts of toxic pollutants in the atmosphere which contain harmful gases like methane (CH4), carbon monoxide (CO), volatile organic compounds (VOC) and carcinogenic polycyclic aromatic hydrocarbons.
  • Farm fires have been an easy way to get rid of paddy stubble quickly and at low cost for several years.

Vehicular Pollution:

  • It is one of the biggest causes of dipping air quality in Delhi in winters and around 20% of 5 in winters comes from it.

Dust Storms:

  • Dust storms from Gulf countries enhance the already worse condition. Dry cold weather means dust is prevalent in the entire region, which does not see many rainy days between October and June.
  • Dust pollution contributes to around 56% of PM10 and the PM2.5 load.

Dip in Temperatures:

  • As temperature dips, the inversion height is lowered and the concentration of pollutants in the air increases when this happens. Inversion height is the layer beyond which pollutants cannot disperse into the upper layer of the atmosphere.


  • Despite the ban on cracker sales, firecrackers are a common sight on Diwali. It may not be the top reason for air pollution, but it definitely contributed to its build-up.

Construction Activities and Open Waste Burning:

  • Large-scale construction in Delhi-NCR is another culprit that is increasing dust and pollution in the air. Delhi also has landfill sites for the dumping of waste and burning of waste in these sites also contributes to air pollution.


  • Deteriorating air quality is worrying amid an increasing number of novel coronavirus disease (Covid-19) cases and deaths.
  • In the World Air Quality report 2020, Delhi has been listed as the 10th most polluted city and the top polluted capital city in the world. However, it shows a boost in Delhi’s air quality by approximately 15% from 2019 to 2020.
  • In July 2020, Greenpeace (non-governmental organisation) found out that of the 28 global cities studied, Delhi bore the highest economic cost of air pollution with an estimated loss of 24,000 lives in the first half of 2020 despite a strict Covid-19 lockdown.
  • Long-term exposure to outdoor and household (indoor) air pollution contributed to over 1.67 million annual deaths from stroke, heart attack, diabetes, lung cancer, chronic lung diseases, and neonatal diseases, in India in 2019 (State of Global Air 2020).


Major Measures Taken:

  • Subsidy to farmers for buying Turbo Happy Seeder (THS) which is a machine mounted on a tractor that cuts and uproots the stubble, in order to reduce stubble burning.
  • The introduction of BS-VI vehicles, push for electric vehicles (EVs), Odd-Even as an emergency measure and construction of the Eastern and Western Peripheral Expressways to reduce vehicular pollution.
  • Implementation of the Graded Response Action Plan (GRAP). It is a set of curbs triggered in phases as the air quality deteriorates, which is typical of the October-November period.
  • Development of the National Air Quality Index (AQI) for public information under the aegis of the Central Pollution Control Board (CPCB).


System of Air Quality and Weather Forecasting And Research

  • SAFAR is a national initiative introduced by the Ministry of Earth Sciences (MoES) to measure the air quality of a metropolitan city, by measuring the overall pollution level and the location-specific air quality of the city.
  • The system is indigenously developed by the Indian Institute of Tropical Meteorology (IITM), Pune and is operationalized by the India Meteorological Department (IMD).
  • The ultimate objective of the project is to increase awareness among the general public regarding the air quality in their city so that appropriate mitigation measures and systematic action can be taken up.
  • SAFAR is an integral part of India’s first Air Quality Early Warning System operational in Delhi.
  • It monitors all weather parameters like temperature, rainfall, humidity, wind speed, and wind direction, UV radiation, and solar radiation.
  • Pollutants Monitored:5, PM10, Ozone, Carbon Monoxide (CO), Nitrogen Oxides (NOx), Sulfur Dioxide (SO2), Benzene, Toluene, Xylene, and Mercury.


The Commission for Air Quality Management in the National Capital Region and Adjoining Areas Bill, 2021:


The Bill was recently introduced in Lok Sabha. The focus is on better coordination, research, identification and resolution of problems surrounding the air quality index.

  • The bill will establish the commission and replace an ordinance.
  • The Bill has taken into consideration the concerns of the farmers following several rounds of negotiations, after they had raised concerns of stiff penalties and possible jail terms for stubble burning.


The bill will apply to the NCR and the areas adjoining the NCR in the States of Haryana, Punjab, Rajasthan and Uttar Pradesh, where any source of pollution is located, causing adverse impact on air quality in the NCR.

What is proposed in the Bill?

The bill provides for the constitution of:

  1. The commission for air quality management in NCR and adjoining areas.
  2. Three sub-committees to assist the commission, including sub-committee on monitoring and identification; sub-committee on safeguarding and enforcement; and sub-committee on research and development.

Need for the Bill:

Sources of air pollution particularly in the NCR consist of a variety of factors which are beyond the local limits. Therefore, a special focus is required on all sources of air pollution which are associated with different economic sectors, including power, agriculture, transport, industry, residential and construction.

  • Since air pollution is not a localised phenomenon, the effect is felt in areas even far away from the source, thus creating the need for regional-level initiatives through inter-State and inter-city coordination in addition to multi-sectorial synchronisation.


About the Commission for Air Quality Management (CAQM):

The Commission was first formed by an ordinance in October 2020.

The erstwhile Environment Pollution (Prevention and Control) Authority, or EPCA had been dissolved to make way for the Commission.

  • The Commission will be a statutory authority.
  • The Commission will supersede bodies such as the central and state pollution control boards of Delhi, Punjab, Haryana, UP and Rajasthan.


Chairperson: To be chaired by a government official of the rank of Secretary or Chief Secretary.


Powers and functions:

  1. It will have the powers to issue directions to these state governments on issues pertaining to air pollution.
  2. It will entertain complaints as it deems necessary for the purpose of protecting and improving the quality of the air in the NCR and adjoining areas.
  3. It will also lay down parameters for control of air pollution.
  4. It will also be in charge of identifying violators, monitoring factories and industries and any other polluting unit in the region, and will have the powers to shut down such units.
  5. It will also have the powers to overrule directives issued by the state governments in the region, that may be in violation of pollution norms.


Other key provisions of the bill:

  1. It has decriminalised the act of stubble burning and withdrawn the clause for possible jail time.
  2. It proposed to levy environmental compensation fees on those who are found to be engaged in stubble burning, including farmers.


Way forward

  • The wheat season is not followed by intensive farm fires, unlike paddy harvesting, as managing wheat stubble is comparatively easy and wheat straw is processed into cattle feed by most farmers.
  • So instead of focusing on farm fires, Delhi should look at local emissions to control the air pollution.
  • Breathing clean air is a fundamental right of every Indian citizen. Therefore, human health must become a priority when it comes to tackling air pollution.




Key Points

  • World Capital City Ranking:
    • Delhi has been ranked as the world’s most polluted capital city followed by Dhaka (Bangladesh), Ulaanbaatar (Mongolia), Kabul (Afghanistan), Doha (Qatar).
  • World Country Ranking:
    • Bangladesh has been ranked as the most polluted country followed by Pakistan and India.
    • The least polluted country is Puerto Rico, followed by New Caledonia, US Virgin Islands
  • World City Ranking:
    • Hotan in China is the most polluted city with an average concentration of 110.2 µg/m³ followed by Ghaziabad in Uttar Pradesh at 106.
  • Indian Scenario:
    • Shows a boost in Delhi’s air quality by approximately 15% from 2019 to 2020. Delhi has been listed as the 10th most polluted city and the top polluted capital city in the world.
    • Ghaziabad is the second most polluted city in the world followed by Bulandshahar, Bisrakh Jalalpur, Bhiwadi, Noida, Greater Noida, Kanpur and Lucknow.
    • Compared to north Indian cities, the cities in the Deccan recorded relatively better air quality, remaining above the daily WHO limits of 25 µg/m3 for most part of 2020. However, every city in India observed air quality improvements compared to 2018 and earlier, while 63% saw direct improvements against 2019.
    • Major sources of India’s air pollution include transportation, biomass burning for cooking, electricity generation, industry, construction, waste burning, and episodic agricultural burning. 2020 was a particularly severe year for agricultural burning in which farmers set fire to crop residue after a harvest. Farm fires in Punjab increased 46.5% over 2019.
  • Covid and Its Impact :
    • In 2020, the spread of Covid-19 raised new concerns as exposure to particle pollution was found to increase vulnerability to the virus and its impact on health.
    • Early reports suggest that the proportion of Covid-19 deaths attributed to air pollution exposure ranges from 7% to 33%.





1) Why does air pollution rise in October every year?


2)India has invested significantly in monitoring air pollution, however, it is important to move ahead in the direction of finding context-specific solutions to solve the problem, Do you agree? Comment. (250 words)