‘Top 20 polluted stations of 2024 located in Delhi-NCR’, Pg4

Key Highlights:

• In 2024, all top 20 most polluted monitoring stations were in Delhi-NCR, with 19 in Delhi.
• Jahangirpuri in North Delhi was the most polluted, with a PM10 concentration of 276.1 µg/m3.
• The analysis assessed air quality trends since the National Clean Air Programme (NCAP) launch in 2019.
• Over 90% of Indian monitoring stations, including most in Delhi-NCR, exceed NAAQS for PM10.

Detailed Insights:

• The Health Effects Institute (HEI) analysis indicates Delhi-NCR dominates India's pollution rankings despite some stations showing declining particulate matter levels.
• Raw PM10 data showed 21 of 27 Delhi stations had declining trends, while Punjabi Bagh and R.K. Puram saw increases.
• After deseasonalisation, 19 stations showed declining PM10 trends, with Jawaharlal Nehru Stadium showing the steepest reduction.
• For PM2.5 levels, 22 stations showed declining trends after deseasonalisation, but Punjabi Bagh and R K Puram showed upward trends.
• The report cautions that the decline in pollution in Delhi is small compared to the city's high baseline pollution levels.
• Uneven monitoring coverage limits the reliability of citywide assessments, especially in cities with only one station.

Key Concepts Involved:

• PM10: Particulate matter with a diameter of 10 micrometers or less, posing respiratory health risks.
• PM2.5: Fine inhalable particles with diameters of 2.5 micrometers or less, deeply penetrating the respiratory tract.
• NAAQS: National Ambient Air Quality Standards, set by the government for acceptable air pollutant levels.
• NCAP: National Clean Air Programme, a government initiative to improve air quality in India.