SO₂ Emissions

SO₂ Emissions

Why it Matters? 

  • The Environment Ministry’s July 2025 move to exempt most coal-based thermal plants from installing Flue Gas Desulphurisation (FGD) systems raises environmental concerns, as SO₂ emissions are a major source of PM2.5 and acid rain, affecting both health and ecosystems. 

What You Should Know? 

  • SO₂ is the main pollutant among Sulphur Oxides (SOₓ), used as an indicator gas for the group. 

  • SO₂ is primarily emitted from fossil fuel combustion at thermal power plants and industrial units. 

  • Coal-based thermal power plants are the largest contributors to sulphur dioxide emissions in India. 

  • Other SO₂ sources include metal smelting, volcanoes, and high-sulphur fuels in ships and locomotives. 

  • SO₂ exposure irritates the respiratory system, especially in children and people with asthma. 

  • SO₂ reacts in the atmosphere to form PM2.5, contributing to cardiovascular and respiratory diseases. 

  • SO₂ contributes to acid rain, which damages forests, lakes, crops, and soil. 

  • At high levels, SO₂ can damage plant foliage and reduce growth. 

  • It contributes to regional haze and reduces visibility by forming fine sulfate particles. 

  • SO₂-related particles can stain and corrode buildings, monuments, and cultural structures.