Nearly 30 per cent of the 14,000 million people in Delhi live in slums and the increasing number of slums and migrants requires better planning so that urban health is managed properly, the WHO report said.

A.K. Sengupta, the officer sustainable development and healthy environment at WHO, said: "Construction related to the Commonwealth Games is bringing in migrants from outside Delhi and adding good amount of slums in the city.

"Unless we manage them, it will deteriorate health conditions in the city."

Sengupta said the same thing happened during the 1982 Asian Games, the last major event to be held in Delhi.

Tens of thousands of migrant labourers are currently in Delhi to help build the facilities for the Commonwealth Games, which are due to open on October 3.

Sengupta said: "They are staying in illegal colonies, in places adjacent to construction sites and on pavements.

"New slums are coming up."

According to official records, Delhi has over 1,500 slums that house more than four million people living without proper sanitation and hygiene.

Sengupta said: "Health and hygiene is a concern.

"It needs to be taken care of well."

WHO officials said Delhi's environment was also becoming increasingly polluted due to the building work for the Games and affecting the overall health of people who live in Delhi.

Sengupta said: "Infrastructure building means dust in the air which is not healthy."

Abdul Sattar, a director in the WHO southeast Asia office, said the UN's health agency hoped that the Indian Government would take appropriate steps to deal with the problems of the slums.

He said: "I hope some of these migrants will return to their home states."


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