Delhi leads India’s most contaminated urban areas ranking, followed by Patna


As per the discoveries of a fresh report on air quality data during the previous year, Aizawl – in Mizoram – boasts of the purest atmosphere in India

As the winter season gradually approaches northern parts of India, the peak contamination period is also anticipated to resume in several major cities across the nation.

A novel analysis from Respirer Reports, an initiative of Respirer Living Sciences, a climate sciences IoT startup headquartered in Mumbai and Pune, assessed the air quality trends in India’s most and least polluted cities during the previous year: 1 October 2022 and 30 September 2023.

Initiating from 1 October, 2023, a revised edition of Graded Response Action Plan (GRAP), a government program to control air pollution, has been enforced in Delhi and 24 adjacent districts, collectively known as the National Capital Region (NCR). This region consists of several locations that frequently ascend Indian and global air pollution rankings.

According to the report’s findings, in collaboration with Climate Trends – a research-based consulting and development initiative dedicated to environmental, climate change, and sustainable development issues – Delhi and other cities within the NCR region still dominate air pollution rankings. Although the air quality in the national capital slightly improved, it was still the most polluted city between 1 October 2022 and 30 September 2023, with a PM2.5 concentration of 100.1 micrograms/cubic metre (μg/m3). This value is more than three times the government’s ‘good’ level and 20 times the World Health Organization’s recommended limit.

In the list of the top 10 polluted cities in India, from 1 October 2022 to 30 September 2023, five NCR cities, namely Delhi, Faridabad, Ghaziabad, Noida, and Meerut, appeared along with Patna and Muzaffarpur in Bihar. The list also included Nalbari in Assam, Asansol in West Bengal, and Gwalior in Madhya Pradesh. Currently, Nalbari and Asansol have only one air quality monitoring station each, whereas Gwalior possesses three stations that record the National Clean Air Programme (NCAP) data.

PM2.5 (fine particulate matter) data is a widely used gauge for assessing the impacts of air pollution on health. This information is available through NCAP, which aims to reduce PM2.5 and PM10 concentrations in Indian cities to 40 per cent of the levels recorded in 2017 by 2026, as reported by Respirer Living Sciences’ press release.

Patna, ranking second with a concentration of 99.7 μg/m3, witnessed a 24 per cent deterioration in air quality compared to the previous year. Significantly, seven cities out of the top 10 polluted cities are situated in Delhi-NCR and Bihar, which are both part of the Indo-Gangetic Plain. A review of air quality during the peak pollution months (October–March) between 2019 and 2023 in six major capitals with air quality challenges shows that Mumbai’s air quality consistently worsened while Delhi’s and Lucknow’s improved.

According to the report, Aizawl, Mizoram, boasts of having the cleanest air in India, with a PM2.5 level of only 11.1 μg/m3.

In the study, the organization examined two sets of air quality data. The first set is the government’s PM2.5 data for the past year, i.e., 1 October 2022 to 30 September 2023, to track improvements in air quality compared to the previous year in the NCR and other cities listed in the NCAP. The second set is the PM2.5 data during winter, roughly from October to March, when pollution levels rise. The study period spans from 2019, when NCAP was launched, to 2023 in six major capitals known for their air quality challenges, including Delhi, Mumbai, Kolkata, Bengaluru, Lucknow, and Patna.

Brought to you by News Live Updates


Please enter your comment!
Please enter your name here