The newly installed continuous air monitoring (CAM) equipment at the Jatiya Sangsad Bhaban has detected methane in the capital's already fouled air.

There are carbon dioxide, carbon monoxide, sulfur oxide, nitrogen oxide and other suspended particulate in the air of Dhaka, making it one of the most polluted cities in the world.

The presence of methane in the air has surprised analysts of the Department of Environment (DoE). However, they are yet to clearly say how dangerous it is to the people, since there is no emission standard for the gas. Nor could they say from which source methane is emanating, sources in the DoE said.

The DoE experts suspect that it might be leaking from the city's domestic gas connections. Such leaks result in accidental fires, they cautioned.

Last month, the Department of Environment installed the monitor at Sher-e-Bangla Nagar on the eastern fringe of the Jatiya Sangsad Bhaban to detect the level of pollution and pollutants.

The computerised machine constantly monitors the air to analyse the level of pollution and pollutants, the DoE sources said.

The monitor was installed as part of the World Bank-aided Air Quality Monitoring Project to help clean the city's air.

Speaker Jamiruddin Sircar will formally open the monitor at a ceremony on Thursday, the sources said.