Authors: Manoj Kumar N and Sunil Dahiya
Key highlights
- In H1 2024, Byrnihat, located on the Assam-Meghalaya border, ranked as the most polluted city in India, with an average PM2.5 concentration of 140 µg/m³.
- Among India’s top 10 polluted cities, three were located in Haryana, two each in Rajasthan and Uttar Pradesh, while Delhi, Assam, and Bihar each had one.
- Ranking as India’s 3rd most polluted city, Delhi’s PM2.5 pollution levels exceeded the NAAQS and were twenty times the WHO annual guideline levels at 102 µg/m³.
- Among 256 cities with PM2.5 data available over 80% of the time period assessed, 163 cities exceeded the annual National Ambient Air Quality Standards (NAAQS) of India (40 µg/m³), while 93 cities were below the annual NAAQS. However, all 256 cities exceeded the annual World Health Organization (WHO) standard (5 µg/m³).
- In 97 National Clean Air Programme (NCAP) cities, all cities exceeded the WHO standard, and 63 cities exceeded the NAAQS.
- Among the 159 non-NCAP cities, all exceeded the WHO standard, and 100 cities exceeded the NAAQS.
- Only 63 cities out of 163 cities exceeding the annual NAAQS are a part of National Clean Air Programme (NCAP) while the other 100 cities still don’t have any action plan to reduce the hazardous air pollution levels.
- From January to June 2024, 140 cities were featured in the daily most polluted cities list. Of these, 51 cities appeared at least 10 times over the six-month period. Byrnihat in Assam-Meghalaya topped the list, featuring 118 times, followed by Gurugram (63 days), Faridabad (62 days), Ballabgarh (58 days), Muzaffarnagar (55 days), Delhi (54 days), Sri Ganganagar (51 days), and Mandi Gobindgarh (51 days).
- In January to June 2024, the cities featured in the annual top 10 most polluted cities list in India were spread across 16 states and union territories (UT), showing how widespread and severe toxic air is across the country.
- Six continuous ambient air quality monitoring stations (CAAQMS) were added between January and June 2024 in Bhiwadi, Durgapur, Pune, Howrah, and Asansol cities, increasing the total from 539 to 545.
- Karnataka and Maharashtra had the highest number of cities under the ‘Good’ and ‘Satisfactory’ categories, with 16 and 30 cities, respectively.
- Bihar had the most cities (10) under the ‘Moderate’ category, while Haryana and Rajasthan each had three cities in the ‘Poor’ category. Only one city, located in Assam, fell under the ‘Severe’ category.
Mid-year air quality assessment for India: January to June 2024
India 2024 H1 ambient air quality data: 1 January to 30 June 2024
Mid-Year Air Quality Assessment for India: January to June 2024 (pdf version)
Data sources
Ambient air quality data recorded by continuous ambient air quality monitoring stations (CAAQMS) is downloaded from the ‘Central Control Room for Air Quality Management – All India‘ dashboard operated by the Central Pollution Control Board (CPCB).