Delhi is world’s most polluted capital as 63 Indian cities in top 100 air pollution list

The sky is filled with smog above Marine Drive in Mumbai, India. AP Photo

A man is seen standing on the ledge of a building as smog envelopes the horizon in New Delhi, India. AP Photo

A sandstorm in Manama, capital of Bahrain. Photo: Getty Images

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The Swaminarayan Akshardham temple is engulfed in a thick layer of smog as air quality hits the ' very poor ' category in New Delhi. EPA

Delhi has emerged as the world’s most polluted capital for the fourth consecutive year as 62 other Indian cities dominated the list of the 100 most polluted places globally in the latest air pollution rankings.

Its air pollution levels were one of the highest among 6,475 cities in 117 countries in 2021, according to a World Air Quality report released by Swiss firm IQAir on Tuesday.

The Indian capital’s air has been ranked the most polluted for high levels of PM 2.5, the fine particles that cause serious respiratory and cardiac diseases.

The city, home to about 32 million, had 96.4 micrograms per cubic meter of PM 2.5 as an annual average, more than 20 times the safe limit of the World Health Organisations at five micrograms per cubic meter.

The pollution levels rose almost 15 per cent compared with the previous year, the report noted.

Particulate Matter 2.5 is the finest dust and other harmful particles measuring less than 2.5 microns that could penetrate deep into the lungs and enter the bloodstream.

Bhiwadi, in the western state of Rajasthan, was the most polluted city in the world, followed by Ghaziabad on Delhi’s eastern border.

Delhi was ranked the fourth most polluted city and was among nine other Indian cities that topped the chart of the 15 most polluted cities in central and south Asia.

Sixty-three Indian cities, mostly in the northern belt, were on the list of 100 most polluted places globally.

The latest report was based on air quality monitoring stations operated by governments, non-profit organisations, research institutions, and citizen scientists around the world, IQAir said.

Large parts of northern India, including its capital Delhi, reel from the worst air pollution during winters, when a thick, toxic layer of smog descends for weeks.

The high level of pollution is blamed on vehicle exhausts, coal-fired power plants, industries and the burning of agricultural residue.

A fatal issue

More than 1.67 million died due to air pollution in 2019, according to a report by the medical journal The Lancet in 2020.

“No cities in India met the WHO air quality guideline of 5 µg/m³. In 2021, 48 per cent of India's cities exceeded 50 µg/m³, or more than 10 times the WHO guideline,” the report said.

Delhi has suffered from the scourge of air pollution for decades but in recent years the toxicity of air has become a public health emergency, particularly during winter.

In recent years, Indian courts, including the Supreme Court, have stepped in to order the government to take measures to reduce pollution levels.

The high levels of pollution prompted the top court to suggest the closure of schools and the government asked tens of thousands of its employees to work from home to reduce vehicular pollution, a major pollutant in the city.

But experts say the latest air pollution rankings are testimony to the country’s failure to bring in policies aimed at cutting down sources of harmful emissions.

India launched a five-year National Clean Air Programme in 2019 to reduce air pollution levels by 20 to 30 per cent of 2017 levels in more than 120 cities.

“There remains a big gap in the formulation of policies and emission standards and their actual implementation on the ground,” Sunil Dahiya, an analyst at the Centre for Research on Energy and Clean Air, told The National.

Mr Dahiya said India would find it hard to improve air quality unless it cuts down on the use of fossil fuels such as coal and petroleum to improve air quality.

“It will be impossible to provide breathable air to citizens and our cities will keep making it to such lists of most polluted cities,” he said.