Context

• In a recent report from the Air Quality Life Index (AQLI), it was estimated that the average Indian is losing 5.3 years of life expectancy due to the adverse health effects of air pollution.
• Beyond the grim statistics of early deaths, air pollution also inflicts a heavy toll in the form of disability and chronic illnesses. This is a serious impact on public health in India.

The Situation of Air Pollution in India

• Dire Situation in Delhi - the National Capital
  • The situation is even worse in Delhi, where the estimated loss of life expectancy due to air pollution is a staggering 11.9 years.
  • Delhi consistently ranks as one of the most heavily polluted cities in the world, often sharing this unfortunate distinction with Wuhan and Lahore, which occasionally take the spotlight for their high levels of carbon pollution.
• Widespread Problem in Indian Cities: In a 2022 list of the 50 most polluted cities put out by IQAir, a Swiss air quality information platform, 39 of them are from India.
• Even Rural Areas Are Not Free of Air Pollution: Because of dust from unpaved roads and smoke from burnt biomass fuels, rural areas too are not free of pollution.
• Gangetic Plains Have the Highest Pollution Levels
  • Geographically, the landlocked Indo-Gangetic plain has the highest levels of pollution as it lacks the dispersal that sea breeze brings to coastal areas.
  • The problem is worsened during the harsh winter as cold air does not flow easily to disperse pollutants.
  • When agricultural crop residue is burnt during this period or when garbage is burnt by the urban poor to keep warm, a harsh winter follows with very high AQI levels. 

Monitored Air Pollutants to Asses the Air Quality and Associated Health Concerns

• Monitored Air Pollutants
  • There are several pollutants that are regularly monitored to assess air quality.
  • These include particulate matter (PM 10 and PM 2.5), nitrogen dioxide, sulphur dioxide, carbon monoxide, ozone, ammonia, and lead.
  • These pollutants are known to have various health and environmental impacts.
• Cadmium as an Air Pollutant is a toxic heavy metal that can have severe health effects when inhaled or ingested.
  • Cigarette smoke is a known source of cadmium exposure, and it contributes to the health risks associated with smoking.
• Fine Particulate Pollution refers to particles smaller than 2.5 microns suspended in the air.
  • These fine particles are a significant concern because they can penetrate deep into the respiratory system and cause various health problems, including respiratory and cardiovascular issues.
• Ultra-Fine Particles are even smaller, with a diameter of less than 0.1 microns.
  • The ability to bypass the body's natural defence mechanisms(such as the respiratory system and potentially enter the bloodstream)makes these particles more dangerous.
  • This could lead to more widespread health issues as these particles may have systemic effects.
• Benzene and formaldehyde from wildfire emissions can lead to cancer.
  • This is an important health concern, as exposure to these chemicals is associated with a higher risk of cancer development.
  • Wildfires are significant sources of air pollution in many regions.

Broader Health Concerns Arising from Air Pollution

• Acute Effects
  • Acute effects like burning eyes, irritation of nose and throat, cough and feeling of choked breath are irritating.
  • Serious harm can arise such as heart attacks and brain strokes caused by atherosclerotic plaques in blood vessels are disrupted by the pollutants, thereby triggering blood clots.
• Health Concerns Due to Long-Term Exposure to Air Pollution
  • It is now known that long-term exposure to air pollution can raise blood pressure (hypertension), lead to cardiovascular, cerebrovascular, and peripheral vascular disease etc.
  • Inflammation stoked by air pollution can damage many organs and lower immunity to infections. PM 2.5 has been found in maternal placenta and foetal brains.
• Effect During Pregnancy
  • Exposure to air pollution during pregnancy increases the risk of stillbirths, neonatal deaths, low birth weight babies and birth defects.
  • Children chronically exposed to air pollution have repeated respiratory infections, susceptibility to asthmatic attacks, lower learning ability and impaired physical growth.

An Analysis of India’s National Air Quality Standards with WHO Standards

• National air quality standards in India are less rigorous than the WHO’s standards. For PM 2.5, the WHO sets a limit of 5 microns while India’s limit is 40 microns.
• India’s AQI has six categories: Good, satisfactory, moderately polluted, poor, very poor and severe.
• An AQI of 0-50 is rated as good, while severe represents an AQI of 401-500.
• Delhi is presently rated as poor (201-300), with predictions of further worsening when crop burning commences.
  • Even when Delhi reports a level of 126, it far exceeds national and WHO standards.

Ways Ahead to Improve the Air Pollution Levels in India

• Bring National Air Quality Standards Close to WHO Standards
  • It must be recognised that health harms from air pollution occur at even lower levels than the national standard.
  • Prolonged exposure to air pollution even at AQI levels declared as satisfactory will have adverse health effects.
  • India must aim to bring them as close to the WHO standards as possible.
• Assessment of Emission Source Distribution and Population Exposure
  • Air pollution in India has diverse sources, both outdoors and indoors.
  • Outdoor pollution is primarily due to particulate matter, originating from vehicles, power plants, factories, garbage dumps, etc.
  • Diesel emissions and dust from roads and construction sites are constant contributors, while seasonal factors like stubble burning exacerbate the issue.
  • Household air pollution primarily results from the use of biomass fuels and open fire-cooking stoves.
  • Emission sources vary significantly across different regions of India and between urban and rural areas, making the problem complex and location-specific.
  • Sources of both ambient (outdoor) and household (indoor) air pollution are well recognised.
  • Therefore, emission source apportionment and population exposure assessments are important for context-relevant control strategies.
• Boader Measures Required than Mere Personal Protections
  • Personal protection measures have only a limited impact. Air purifiers work only in a closed room and may be best used to protect persons who are confined there because of severe illness or disability.
  • More than these measures, the protection will come from clean transport (like EVs), increased use of public transport in place of personal vehicles, rapid transition to renewable energy sources from fossil fuels, cessation of stubble and garbage burning, good construction practices and efficient debris disposal.
  • Household air pollution is being addressed through the substitution of biomass with natural gas and better ventilation of kitchens.

Conclusion

• If a significant number of Indians are to avoid being restricted to their homes or hospitals due to the detrimental effects of outdoor air on their health, it is imperative to address ambient air pollution with heightened determination.
• This requires proactive public policies, efficient enforcement, vigilant monitoring, and adaptable innovations that respond to consistent and accurate data streams.