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As per World Cities Report 2024: Cities and Climate Action of UN-Habitat, urban air pollution accounted for 6.7 million premature deaths in 2019, making it the world's largest environmental risk factor for disease and premature death.

More on the News

• 6^th Annual World Air Quality Report by IQAir found New Delhi to be the most polluted capital city in the world.
  • 9 out of the 10 most polluted cities in the world were found to be located in India.

Reasons for urban air pollution in India

• Meteorological and Geographical Factors
  • During Gurugram's dust storms, 57% of days record ozone levels above US's National Ambient Air Quality Standards (NAAQS) limits.
  • Low Rainfall and Winds: Low rainfall in September-October and sluggish winter winds contribute to stagnant pollutant levels in north India.
  • Airshed Dynamics: Regional air pollution spreads through wind patterns; e.g., 50% of Delhi's PM2.5 originates from Haryana and Uttar Pradesh.
  • Dust Storms: Dust from the Sahara and Thar deserts, rich in nitrates, contributes to surface ozone formation; 
    • Topography: Northern India's low-lying terrain traps pollutants, with the Himalayas blocking dispersion.
  • Temperature Inversion: Winter conditions trap cooler air near the ground, preventing pollutant dispersal.
• Agricultural practices: Stubble Burning in Punjab and Haryana produces toxic haze, impacting air quality in adjacent regions.
• Urban and Industrial Factors
  • Construction and Demolition Waste: Dust from these activities contributes significant particulate matter and volatile organic compounds.
  • High Vehicle Density: The total number of vehicles sold has increased from around 178 lakh in 2010-11 to around 215  lakh in 2019-20 (MoRTH) 
  • Unscientific Waste Disposal: Open burning of waste and landfill fires emit pollutants, e.g., Mumbai's landfill fires produce 22,000 tons pollutants annually.
  • Industrial Emissions: Industries like iron and steel, cement, sugar, and onceptual are major polluters, with Rajkot (42%) and Pune (30%) most affected by industrial PM2.5 emissions.

• Additional Sources
  • Biomass Burning: Cooking stoves, brick kilns, and factory exhausts contribute to local air pollution.
  • Cultural and Festive Practices: Increased firecracker usage during Diwali exacerbates pollution levels.
    • In November 2024, overall level of PM2.5 in Delhi was 401.1 ug/m3 – about 26 times the WHO's permissible limit of 15 ug/m³ for a 24-hour period.

Concerns and issues arising because of urban air pollution

• Health Impacts: Urban air pollution contributes to respiratory infections, lung diseases, and cardiovascular conditions. 
  • In Delhi alone, over 30,000 deaths are attributed to air pollution annually, with approximately 2 million deaths nationwide.
• Economic Losses: Premature deaths and morbidity resulted in an economic loss of about $36.8 bn annually, equating to 1.36% of India's GDP in 2019 (World Bank).
• Damage to Materials and Structures: Emissions of SO₂ and NO₂ harm flora, fauna, and materials, causing damage to iconic structures. 
  • For instance, the Taj Mahal's white marble is yellowing due to industrial SO₂ emissions and acid rain.
• Urban Heat Island (UHI) Effect: Built-up urban areas experience higher temperatures than rural surroundings due to greenhouse gas emissions, exacerbating urban warming.
• Ecosystem and Biodiversity Degradation: Air pollution leads to acidification of lakes, eutrophication, and mercury accumulation in aquatic food chains.
  • Impact on Plants: Nitrogen deposition from acid rain causes defoliation, discoloration, weakened crowns, and increased vulnerability to pests.
  • Ozone Damage: Reduces photosynthesis and slows plant growth, impacting overall vegetation health.

Steps Taken by the Government of India to Curb Air Pollution

• National Air Quality Index (refer to the infographics) 
• Policy and Regulatory Framework
  • National Clean Air Programme (NCAP), 2019: Aims to reduce particulate matter concentrations by 40% by 2026 in 131 cities.
  • Graded Response Action Plan (GRAP): Emergency measures to combat air pollution in Delhi-NCR.
  • Commission for Air Quality Management (CAQM), 2021: Established for improved air quality management in the National Capital Region.
  • Central Pollution Control Board (CPCB): Issues directions under the Air(Prevention and Control of Pollution) Act, 1986, addressing vehicular emissions, solid waste burning, etc.
• Air Quality Monitoring and Awareness: System of Air Quality and Weather Forecasting and Research (SAFAR) Portal provides air quality updates to enhance public awareness and mitigation actions.
• Pollution Control and Sustainable Transport
  • National Electric Mobility Mission Plan (NEMMP) 2020: Promotes electric vehicles under the FAME India Scheme.
  • Vehicular Pollution Control: Cleaner fuels (CNG, LPG, BS-VI standards), ethanol blending, and promotion of public transport.
• Clean Energy Initiatives: Targets 50% non-fossil fuel electricity generation by 2030 under Nationally Determined Contributions (NDCs); promotes LPG usage under Pradhan Mantri Ujjwala Yojana for rural households.

Ways to curb urban air pollution in India

• Urban Planning and Green Initiatives: 
  • Green Spaces: Promote vegetation in urban areas through urban gardens, living plant walls to combat greenhouse gas emissions and counter urban heat island effect.
  • Clean Air Zones: Establish clean air zones with strict emissions standards in high-pollution areas.
    • For eg., London's Ultra-Low Emission Zone (ULEZ) reduced NO₂ by 44% and PM2.5 by 27%.
• Sustainable Transportation: Reallocate road space, invest in public transport, designate pedestrian-only areas, and enhance cycling facilities.
  • For eg., Copenhagen's Green Wave technology coordinates traffic lights for cyclists, to promote cycling.
• Technological and Scientific Solutions
  • Technology Modifications: Adopt cleaner technologies such as fuel cell vehicles, ultra-low sulfur fuels, or alternative fuels like methanol (Brazil) and hydrogen fuel (Japan).
  • Artificial rain via cloud seeding: It involves dispersing materials such as silver iodide, into the clouds; which act as nuclei around which moisture can condense and fall as rain; helping settle pollutants and smog.
• Waste Management: Use methods like bio-remediation (drying of waste) and biomining to process landfill waste.
  • For eg: Dhapa landfill of Kolkata has reduced landfill fires and improved air quality. 
• Integrated Policy Approaches
  • Airshed Management: Address pollution holistically by focusing on natural flows and dispersion patterns across regions.
  • International Cooperation: Revive agreements like the Malé Declaration (1998) to tackle transboundary pollution with regional partners (Bangladesh, Bhutan, India, Iran, Maldives, Nepal, Pakistan, Sri Lanka).