Thirteen of the world’s 20 most polluted cities are located in India, with Byrnihat in Meghalaya claiming the top spot, according to a recent report released on March 11.
The World Air Quality Report 2024, compiled by Swiss air quality technology firm IQAir, has revealed that Delhi continues to hold the title of the most polluted capital city globally. Meanwhile, India has been ranked as the fifth most polluted country in 2024, a slight improvement from its third-place position in 2023.
The report highlighted that India experienced a 7 per cent reduction in PM2.5 concentrations in 2024, with levels averaging 50.6 micrograms per cubic metre, down from 54.4 micrograms per cubic metre in 2023. Despite this improvement, six of the world’s 10 most polluted cities are still in India.
Delhi’s air quality remained alarmingly poor, with an annual average PM2.5 concentration of 91.6 micrograms per cubic metre, barely lower than the 92.7 micrograms per cubic metre recorded in 2023.
The 13 Indian cities featured in the global top 20 most polluted list include Byrnihat, Delhi, Mullanpur (Punjab), Faridabad, Loni, New Delhi, Gurugram, Ganganagar, Greater Noida, Bhiwadi, Muzaffarnagar, Hanumangarh, and Noida.
Alarmingly, 35 per cent of Indian cities reported annual PM2.5 levels that exceeded 10 times the World Health Organization’s (WHO) recommended limit of 5 micrograms per cubic metre.
Air pollution continues to pose a significant health threat in India, with studies estimating that it reduces life expectancy by approximately 5.2 years. A study published in The Lancet Planetary Health last year indicated that around 1.5 million deaths annually in India between 2009 and 2019 were potentially linked to prolonged exposure to PM2.5 pollution.
PM2.5 refers to fine particulate matter smaller than 2.5 microns, which can penetrate the lungs and bloodstream, leading to respiratory issues, cardiovascular diseases and even cancer. Major sources of PM2.5 include vehicle emissions, industrial pollution, and the burning of wood or agricultural waste.
Dr Soumya Swaminathan, former Chief Scientist at the WHO and advisor to the Indian health ministry, noted that while India has made strides in air quality monitoring, concrete action remains insufficient.
“We have the data; now we need action. Some solutions are straightforward, such as replacing biomass with LPG. India already has a scheme for this, but we must further subsidise additional cylinders. The first cylinder is free, but the poorest families, especially women, should receive higher subsidies. This would not only improve their health but also reduce outdoor air pollution,” she told the Press Trust of India in an interview.
In urban areas, expanding public transport and imposing fines on high-emission vehicles could help mitigate pollution.
“A combination of incentives and penalties is essential,” she added.
Dr Swaminathan, who also served as Director General of the Indian Council of Medical Research, emphasised the importance of strict enforcement of emission regulations. “Industries and construction sites must comply with laws and install equipment to reduce emissions, rather than cutting corners,” she stated.