India home to 21 of the world's most polluted cities, new data reveals

India has once again topped an annual list of the 100 cities with the worst air quality in the world.

According to new data from a 2019 air quality report by Swiss and US-based company IQAir, 21 of the world's 30 most polluted cities are Indian - with six of them appearing in the top ten.

While India had the most cities on the list, it was only the fifth most air polluted country overall - with Bangladesh being the worst offender.

"Air pollution continues to pose one of the biggest threats to human health," IQAir said in a statement. "The new dataset highlights elevated air pollution levels as a result of climate change events, such as sandstorms and wildfires.

What's even more alarming is the "silent killer" of air pollution is not monitored in many areas of the world, IQAir chief executive Frank Hammes said. Some of those areas are estimated to have some of the worst air quality in the world.

"Africa, a continent of 1.3 billion people, currently has less than 100 monitoring stations," Hammes said. "More real-time air quality data leads citizens and governments to make better decisions that will improve the lives of millions for decades to come."

IQAir air quality monitoring director Yann Boquillod said cities that want to become more sustainable need to make better choices, CNN reports.

Ghaziabad, India.
Ghaziabad, India. Photo credit: Getty

The world's filthiest cities, as per the findings:

  • Ghaziabad, India
  • Hotan, China
  • Gujranwala, Pakistan
  • Faisalabad, Pakistan
  • Delhi, India
  • Noida, India
  • Gurugram, India
  • Raiwind, India
  • Greater Noida, India
  • Bandhwari, India.
Traffic jam in Dhaka, Bangladesh.
Traffic jam in Dhaka, Bangladesh. Photo credit: Getty

The world's filthiest countries:

  • Bangladesh
  • Pakistan
  • Mongolia
  • Afghanistan
  • India
  • Indonesia
  • Bahrain
  • Nepal
  • Uzbekistan
  • Iraq.

Where does New Zealand rank?

According to the findings, New Zealand is 91st - slightly more filthy than Estonia, Sweden, and Norway but not quite as polluted as Canada, Australia, and Ecuador.

Our top three most polluted areas are Auckland's central business district and the rural areas of Winton and Invercargill.

Sydney was 91st on the list, while Auckland wasn't in the top 100.
Sydney was 91st on the list, while Auckland wasn't in the top 100. Photo credit: Getty

None of those, however, make the top 100 of the world's most polluted cities.

Across the Tasman, Sydney comes in at 91st, Canberra 93rd, and Melbourne 94th.