Nearly a quarter of the police force in the southern city of Bangalore are suffering from hearing disabilities due to increasing noise pollution.

A pilot study conducted by Bangalore's Institute of Speech and Hearing reveals that traffic constables at the city's main junctions are the worst hit.

The city has a total of nearly 2,000 police officers.

Mrs Madhuri Gore, who conducted the survey, says noise levels in the city's residential areas were as high as 76 decibels - almost 10dB above the levels prescribed by the central pollution board for commercial areas.

Calcutta is known as the noisiest city in the country with a general level of 88dB.

Police officials in Bangalore have admitted that the noise level in the city is affecting the health of its officers, and as a result, they say it is affecting their efficiency at work.

Doctors say exposure to high decibel levels can lead to high blood pressure, cardiac problems and insomia.