More than 5,000 Indian school children set a world record by forming the largest shape of human lungs in New Delhi, among the world's most polluted cities, to raise awareness about the dangers of pollution.

The 5,009 students from more than 35 schools stood together to create the lungs at the city's Thyagaraj stadium on Saturday, according to the organizers, Lung Care Foundation.

The Guinness World Records certified the effort created the largest human image of an organ, the foundation's founder Arvind Kumar said on Sunday.

The children wore pink, blue and black overalls and the formation transformed to show the effects of pollution, with the pink lungs turning to black.

The previous records were held by Abu Dhabi and China involving 3,196 and 1,500 people, respectively.

"We believe it's time that citizens act rather than wait for government measures. The children took pledges to become lung ambassadors, talk to neighbours, family and acquaintances to create a mini-revolution which sees people taking up responsibility to fight pollution," Kumar said.

The Indian capital, which has a population of more than 20 million, sees several days of spiking pollution and smog every winter.

Pollution in Indian cities, particularly in the north, has long impacted the health of residents but the government has done little to check worsening air quality.

A study released by the Lancet medical journal in October linked pollution to 2.5 million deaths in India in 2015.