Context: The University of Chicago has published the Air Quality Life Index (AQLI) report for 2023. AQLI data emphasises that ambient Particulate Pollution poses the world’s greatest external risk to human health.

Major Highlights:

• Data shows that failure to meet the World Health Organisation’s guidelines on reducing PM2.5 (particulate matter) pollution to 5 μg/m3 would cut global life expectancy by 2.3 years. 
• (Chart 1) South Asia is at the centre of the crisis.
  • According to AQLI data, from 2013 to 2021, particulate pollution in South Asia surged by 9.7%, which is estimated to reduce life expectancy in the region by an additional six months.
  • Bangladesh, India, Nepal, and Pakistan, where 22.9% of the global population lives, are the most polluted countries in the world.
• (Chart 2) In India, the second-most polluted country (most polluted Bangladesh) in the world in 2021, particulate pollution is the greatest threat to human health.
  • Data reveal a further rise in PM2.5 pollution from 56.2 μg/m3 in 2020 to 58.7 μg/m3 in 2021, exceeding the WHO guidelines by more than 10 times. The average Indian resident is set to lose 5.3 years of life expectancy if WHO guidelines remain unmet. 
• Chart 3 shows the most polluted States in India and the potential life expectancy loss if pollution levels do not meet WHO guidelines. In Delhi, the world’s most polluted city, 18 million people could lose 11.9 years of life expectancy relative to the WHO guideline and 8.5 years of life expectancy relative to the national guideline if current pollution levels persist.
  • The northern plains, home to over half a billion people and 38.9% of India’s population is the most polluted region. 
  • The northern plains include the States and Union Territories of Bihar, Chandigarh, Delhi, Haryana, Punjab, Uttar Pradesh, and West Bengal. 
• Chart 4 shows the annual average PM2.5 concentrations in India, the northern plains, and all other regions. Pollution, once concentrated in the northern region, has spread to other parts of the country over the last two decades. All of the 521.2 million people living in the Northern Plains — 38.9 per cent of India’s population — live in areas where the annual average particulate pollution level is 17.3 times higher than the WHO guideline. 

Air Pollution:

• Air pollution refers to the release of pollutants (a complex mixture of solid particles, liquid droplets, as well as gases) into the air which is detrimental to human health and the planet.
• Major Pollutants:

• Ozone (O3): Terrestrial O3 is created by the chemical reaction between oxides of nitrogen (NOx) and volatile organic compounds (when pollutants emitted by cars, power plants, refineries etc. chemically react in the presence of sunlight)
• Nitrogen dioxide (NO2): emissions from motor vehicle exhaust, industrial facilities, and chemical solvents.
• Carbon monoxide (CO): released on burning fuel containing carbon, such as wood, coal and petrol.
• Sulfur dioxide (SO2): burning fossil fuels by power plants and other industrial facilities.
• PM2.5 and PM10
• Methane: landfills, waste, fossil fuel and agricultural industry.

Impacts of Air Pollution:

Air pollution is one of the biggest environmental threats to human health, alongside climate change. 

• Human Health:
  • Decreased life expectancy due to severe diseases induced by air pollution. Every year, exposure to air pollution is estimated to cause 7 million premature deaths. In children, effects include reduced lung growth and function, respiratory infections and aggravated asthma. 
  • Developmental delay: New research has also shown an association between prenatal exposure to high levels of air pollution and developmental delay at age three, as well as psychological and behavioural problems later on, including symptoms of attention deficit hyperactivity disorder (ADHD), anxiety and depression.
• Climate Change including global warming, acid rain, depletion of ozone layer etc.
• Wildlife: Toxic chemicals present in the air can force wildlife species to move to new place and change their habitat.
• Economy: Increasing healthcare costs, reducing productivity, environmental damage. As per World Air Quality Report 2022, Economic cost of air pollution to Indian economy is estimated to be more than US$150 billion per year.

Particulate Pollution:

• Particulate pollutants are minute solid particles or liquid droplets in the air. These are present in Particulate Matter (PM 10, PM 2.5) is composed of a mixture of solids and liquids found in the air. 
• Particulates in the atmosphere may be viable or non-viable.
  • Viable: They are minute living organisms that are dispersed in the atmosphere (e.g., bacteria, fungi, moulds, algae etc.)
  • Non-Viable: They are small solid or liquid particles suspended in the air that are not capable of reproducing or growing.
    • Smoke particulates from burning of fossil fuel, garbage etc.
    • Dust, Sand, pulverized coal, cement and fly ash from factories etc.
    • Mists produced by particles of spray liquids and by condensation of vapours in air.
    • Fumes by the condensation of vapours during sublimation, distillation, boiling and several other chemical reactions. E.g., Organic solvents, metals and metallic oxides form fume particles.
• Particulate Matter (PM) 2.5 and PM 10 refer to different size categories of airborne particles that can have various impacts on human health and the environment.
  • PM10 (particles with a diameter of 10 micrometres or less) are small enough to pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health effects. Particles with a diameter of 10 microns or less, (≤ PM10) can penetrate and lodge deep inside the lungs.
  • PM2.5: The particles with a diameter of 2.5 microns or less, (≤ PM2.5) can penetrate the lung barrier and further enter the body through the bloodstream, affecting all major organs. PM2.5 can cause diseases both to our cardiovascular and respiratory systems, provoking, for example, stroke, lung cancer and chronic obstructive pulmonary disease (COPD). 

WHO’s Global Air Quality Guidelines:

• The WHO Air quality guidelines are a set of evidence-based recommendations of limit values for specific air pollutants developed to help countries achieve air quality that protects public health.
• In 2021, WHO released a revised Global Air Quality Guidelines announcing more stringent limits for six pollutant categories – particulate matter (PM), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO). 
• Although the guidelines are neither standards nor legally binding criteria, they are designed to offer guidance in reducing the health impacts of air pollution based on expert evaluation of current scientific evidence. 
• The guidelines the stage for eventual shifts in policy in the government towards evolving newer stricter local and national air quality standards and will help countries in protecting health as well as mitigating global climate change.

• PM2.5: The upper limit of annual PM2.5 as per the 2005 standards is 10 micrograms per cubic metre. It has been revised to 5 micrograms per cubic metre. The 24-hour ceiling used to be 25 micrograms but has now dropped to 15. 
• PM10: For PM10, the upper limit is 20 micrograms and has now been revised to 15 whereas the 24-hour value has been revised from 50 to 45 micrograms.

Impact of guidelines on India: 

• The move does not immediately impact India as the National Ambient Air Quality Standards (NAAQS) do not meet the WHO’s existing standards. 

• The government has a dedicated National Clean Air Programme that aims for a 20% to 30% reduction in particulate matter concentrations by 2024 in 122 cities, keeping 2017 as the base year for the comparison of concentration.
• India’s NAAQs — last revised in 2009 — specify an annual limit of 60 micrograms per cubic metre for PM 10 and 100 for a 24-hour period. Similarly, it is 40 for PM 2.5 annually and 60 for a 24-hour period. There are also standards for a host of chemical pollutants including sulphur dioxide, lead and nitrogen dioxide.

India’s Initiatives:

• The Air (Prevention And Control Of Pollution) Act, 1981: The Act aims to control and prevent air pollution in India, and some of its main objectives are:
  • Prevent, control, and reduce air pollution.
  • Central Pollution Control Board (CPCB) and State Pollution Control Board (SPCB) were given the responsibility.
• National Clean Air Programme (NCAP): It was launched in 2019, now renamed National Clear Air Mission is a long-term, time-bound, national level strategy to tackle the air pollution across the country comprehensively.
  • NCAP targets to achieve 20% to 30% reduction in PM10 and PM2.5 concentrations by 2024 keeping 2017 as the base year for the comparison of concentration.
  • 131 non-attainment cities mostly in Indo-Gangetic Plains have been identified based on ambient air quality data for the period 2011 – 2015 and WHO report 2014/2018. 
• Commission for Air Quality Management: The Commission for Air Quality Management in the National Capital Region and adjoining areas 2020 — with a provision for a fine of Rs 1 crore and/or jail for 5 years for those violating air pollution norms.
• Clean Air India Initiative to curb air pollution in Indian cities by promoting partnerships between Indian start-ups and build a network of entrepreneurs working on business solutions for cleaner air. Under it, an ‘INDUS impact’ project aims to halt the burning of paddy stubble by promoting businesses that “up cycle” it by using paddy straw as feedstock to make materials that would find use in construction and packaging.
• Notification of National Ambient Air Quality Standards, National Air Quality Index and sector-specific emission and effluent standards for industries to reduce emission of PM 10, SO2 and oxide of nitrogen.
  • Air Quality Index (AQI):
    • AQI is an initiative of the Ministry of Environment Forest and Climate Change under Swachh Bharat Abhiyan.
    • National Air Quality Index was launched in 2014 as ‘One Number- One Color-One Description’ for the common man to judge the air quality within his vicinity.
    • The colour-coded index has six AQI categories, namely Good, Satisfactory, Moderately polluted, Poor, Very Poor, and Severe.
    • The index will measure eight major pollutants, namely, particulate matter (PM) 10, PM2.5, Ozone (O3), Sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), lead (Pb) and ammonia (NH3).
  • National Ambient Air Quality Standards (NAAQS)
    • Central Pollution Control Board (CPCB) has notified these standards under powers given to it under the Air (Prevention and Control of Pollution) Act, 1981.
    • It covers 12 pollutants: Sulphur Dioxide, Nitrogen Dioxide, PM-10, PM-2.5, Ozone, Lead, Carbon Monoxide, Ammonia, Benzene, Benzopyrene, Arsenic, Nickel.
• Air Quality Early Warning System:
  • The initiative comes under the Ministry of Earth Sciences and Environment.
  • Air Quality Early Warning System for Delhi has been announced by the Central government that can alert, three days in advance, about the likelihood of extreme pollution events & dust storms.
  • The air pollution system has been developed jointly by Indian Institute of Tropical Meteorology (IITM), India Meteorological Department, National Centre for Medium Range Weather Forecasting (NCMRWF).
  • It intends for real time observations with 72-hour lead time of air quality over Delhi region.
  • It provides details about natural aerosols like dust from dust storms and particulate matter using different satellite data sets.
  • It will provide warning messages and Alerts to take necessary steps as per Graded Response Action Plan (GRAP).
• Promotion of fuel standards: Leapfrogging from BS-I to BS-VI fuel and ban on pet coke and furnace oil.
  • Bharat Stage Norms (BS Norms) are rules that determine the maximum limit of pollutants vehicles (Including motor vehicles) can emit.
  • The standards, based on European regulations were first introduced in the year 2000.
  • 2020 – BS-VI has been introduced directly bypassing BS-V.
  • BS VI is expected to be the same as that of the Euro VI norms and will be declared by CPCB (Central Pollution Control Board) under the Ministry of Environment & Forests and Climate Change.
    • BS VI norms will cut down the presence of sulphur (in comparison to BS IV) from 50 ppm to 10 ppm (80%)
    • Implementation of BS VI will ensure cutting down harmful NOx (nitrogen oxides) from diesel cars by nearly 70%. In the petrol cars, they can be reduced by 25%.
    • Particulate matter like PM 2.5 and PM 10 are the most harmful components and the BS VI will bring down the cancer-causing particulate matter in diesel cars by a phenomenal 80%.
• Swachh Vayu Survekshan: It has been conducted since 2016 and is the world’s largest urban sanitation and cleanliness survey. The primary goal of Swachh Survekshans is to encourage large-scale citizen participation and create awareness amongst all sections of society about the importance of working together towards making towns and cities better places to reside in.
  • It is conducted under the ambit of the Swachh Bharat Mission (Urban). Nodal Ministry: Ministry of Housing and Urban Affairs (MoHUA).
  • ‘Swachh Vayu Sarvekshan- Ranking of Cities’: The guidelines on ‘Swachh Vayu Sarvekshan- Ranking of Cities’ released under National Clean Air Program (NCAP).
  • Promotes ranking of 131 cities in the country for implementing City Action Plans prepared as part of NCAP for reducing air pollution up to 40% by 2025-26.
• Subsidy to cooking fuel under Pradhan Mantri Ujjwala Yojana (PMUY) to dramatically expand access to clean energy, especially for rural households, to curb indoor pollution. 
• Encouraging Alternatives: Promotion of public transport and network of metro, e-rickshaws, promotion of car-pooling, smog towers, etc.

Way Forward:

• Need for a stronger mandate: NCAP is not legally binding, it will continue to be an advising programme. Legal support is needed not just to give state and local governments more enforceable mandates, but also to ensure inter-ministerial collaboration.
• Need for Higher ambitions: India’s air pollution standards are more relaxed in comparison to WHO’s prescribed guidelines. The current NCAP goal levels would not result in breathing air quality in the country, since pollution levels are so high over most of the country. Thus, efforts are needed to make the guidelines more stringent with revised targets.
• Air-shed approach: Need to adopt an air-shed approach to take measures to deal with air pollution. Under this approach, the policymakers will have to plan actions keeping in view topographical, climatic, and other common elements that contribute to air pollution in the region.