Nearly 60 per cent of pollution in Delhi caused by fine particulate matter (PM 2.5) originates from outside, with the neighbouring states of Haryana and Uttar Pradesh being major contributors to it, a new study on city’s air quality has said.

The study also revealed that the transportation sector contributes to a relatively low 20 per cent of PM 2.5, belying the notion that it is one of the biggest pollutants in the national capital.

The study by CSIR-National Environmental Engineering Research Institute (NEERI), an institute under the ministry of science and technology, said that Delhi urgently requires cooperation of neighbouring states to deal with the menace.

It pointed out that burning of biomass in cooking stoves and power plants is a major source of pollutants depleting the air quality. PM 2.5 pollutants are micro particles that can enter the bloodstream and cause damage to the respiratory system.

“Only 40 per cent of PM 2.5 that an average inhabitant of Delhi is exposed to originates from within the city. Instead, the majority (60 per cent) comes from outside Delhi, with half from the surrounding states of Haryana and Uttar Pradesh, and a quarter from sources even further away, including neighbouring areas, and a quarter from natural resour-ces,” the study said.

Markus Amann, programme director of Air Quality and Greenhouse Gases Programme, who led the research, said, “Delhi cannot solve this problem alone and there is a need to talk to outside (neighbouring states).”

Citing the example of China, Mr Amann said even Beijing had to talk to its neighbouring provinc-es to curb pollution.