Study Reveals Potential to Prevent 124,000 Annual Deaths by Mitigating SO₂ Emissions
Key Points
Last Updated: 13-05-2026. A groundbreaking study by IIT Delhi reveals that India could prevent over 124,000 annual deaths by mitigating sulfur dioxide (SO₂) emissions from coal-fired power plants. This is crucial for UPSC aspirants, especially for General Studies Paper 3 focusing on environmental issues and public health.
Key Facts About SO₂ Emissions and Mitigation
- SO₂ Emissions Rise: India's emissions from coal-fired power plants increased from 2.36 thousand kilotonnes in 2005 to 5.05 thousand kilotonnes in 2021, with a further 30% spike in 2023.
- Secondary Pollutant Formation: SO₂ is a precursor to secondary inorganic aerosols, contributing significantly to PM2.5 levels.
- Geographic Hotspots: Maharashtra, Tamil Nadu, and Karnataka face the highest avoidable mortality rates due to population density.
- Environmental Equity: Scheduled Castes, Scheduled Tribes, and lower-income groups suffer disproportionately from this pollution.
- Technology Debate: Advocates for mandatory flue gas desulphurisation (FGD) systems, despite the Centre's 2025 relaxation of emission norms.
- Policy Recommendations: Calls for strict enforcement of MoEFCC norms and a shift towards cleaner fuels and electric vehicles.
India's Environmental Health and Policy
The study underscores the macro-level significance of mitigating SO₂ emissions in aligning with India's strategic goals for sustainable development and public health improvement. By addressing these emissions, India can improve its global environmental rankings and contribute to international climate commitments, fostering economic growth through healthier populations.
UPSC Relevance
General Studies Paper 3: Environmental pollution, health impacts, and technology interventions.
Prelims Angle: Facts about SO₂ emissions, FGD technology, and emission trends.
Mains Angle: Analytical themes on environmental justice, policy enforcement, and technology adoption.
Essay Paper: Topics on sustainable development and public health.
Frequently Asked Questions (FAQs)
- What was the core finding of the IIT Delhi study regarding mortality?
The study estimated that full mitigation of SO₂ from coal plants could prevent 124,000 annual deaths, including significant cardiovascular and respiratory fatalities. - How does Flue Gas Desulphurisation (FGD) contribute to a circular economy?
The process produces gypsum as a byproduct, which is a valuable commercial material used in the construction industry for making cement and drywall. - What is the primary pollutant formed when SO₂ reacts in the atmosphere?
SO₂ acts as a precursor to secondary inorganic aerosols (sulphates, nitrates, and ammonium), which are major components of hazardous PM2.5 levels.
Detailed Coverage
- Study by IIT Delhi published in the journal Nature.
- Potential to prevent 124,000 annual deaths by mitigating SO₂ emissions.
- SO₂ emissions from CFPPs rose from 2.36 to 5.05 thousand kilotonnes from 2005 to 2021.
- 30% spike in emissions reported in 2023.
- SO₂ is a primary precursor to secondary inorganic aerosols.
- Maharashtra, Tamil Nadu, and Karnataka face the highest avoidable mortality.
- Chhattisgarh and Odisha would see significant air quality improvements.
- Scheduled Castes (SC), Scheduled Tribes (ST), and lower-income groups are disproportionately affected.
- Mandatory installation of flue gas desulphurisation (FGD) systems is advocated.
- Health-related monetary gains from FGD systems outweigh their costs.
- In July 2025, 79% of coal units were exempted from FGD installation.
- Strict enforcement of MoEFCC emission norms is recommended.
- Emphasis on prioritization of pollution hotspots.
- Encouragement of cleaner cooking fuels and electric vehicles.
- FGD technology removes SO₂ from exhaust gases before release.
- Gypsum produced from FGD can be sold for construction materials.