India is still a hotspot for air pollution, with 13 of the top 20 most polluted cities in the world found in the country, as per the recent World Air Quality Report 2024 by Swiss air quality technology firm IQAir. Byrnihat in Assam has been declared the world's most polluted city, due to the continued air quality crisis in the nation.

Delhi remains the world's most polluted capital city with its grim record. The report indicates that India was the fifth most polluted country in the world in 2024, down from third position in 2023. While there has been some improvement, six of the world's top 10 most polluted cities are located in India.

The report noted that India’s average PM2.5 concentration in 2024 was 50.6 micrograms per cubic metre, down 7% from 54.4 micrograms in 2023. However, Delhi’s PM2.5 levels remained alarmingly high at 91.6 micrograms per cubic metre, only slightly better than 92.7 micrograms recorded the previous year.

Which Indian cities are among the most polluted?

Besides Byrnihat and Delhi, other highly polluted Indian cities include:

Mullanpur (Punjab)

Faridabad

Loni

New Delhi

Gurugram

Ganganagar

Greater Noida

Bhiwadi

Muzaffarnagar

Hanumangarh

Noida

These cities indicate the continued battle with air quality, fueled by automobile emissions, industrial pollution, and burning of wood and agricultural waste.

Why is PM2.5 pollution a major health risk?

PM2.5 is small air pollution particles that are less than 2.5 microns. Such particles find their way into the lungs and the blood and result in serious health problems such as respiratory issues, heart disease, and even cancer.

A Lancet Planetary Health study published last year put the number of annual deaths in India between 2009 and 2019 due to long-term exposure to PM2.5 pollution at around 1.5 million. The report further said that 35% of Indian cities reported PM2.5 concentrations more than 10 times above the World Health Organization's (WHO) safe limit of 5 micrograms per cubic meter.

How can air quality be improved?

Former WHO chief scientist and health ministry advisor Soumya Swaminathan stressed that although India has improved in gathering air quality data, more needs to be done to address the situation.

"We have the data; now we need action. Some solutions are easy, like replacing biomass with LPG. India already has a scheme for this, but we must further subsidize additional cylinders. The first cylinder is free, but the poorest families, especially women, should receive higher subsidies. This will improve their health and reduce outdoor air pollution," Swaminathan told PTI.

She also recommended enhancing public transport and imposing penalties on specific vehicles to curb emissions. "A mix of incentives and penalties is necessary," she said.

"Finally, strict enforcement of emission laws is crucial. Industries and construction sites must comply with regulations and install equipment to cut emissions instead of taking shortcuts," Swaminathan added.

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