'Methane, petroleum traces behind froth, fire in Belandur lake'

 Bacterial microbes emitting methane, coupled with effluents containing traces of petroleum, are the culprits behind the froth and the recent fire in Belandur lake, a study by the Department of Environment Sciences (DES) of Bangalore University (BU) has found.

Contrary to the statements of the Karnataka State Pollution Control Board and the State government officials, who suspect a ‘mischief’ behind the froth and fire in the lake, Nandini, professor, DES, BU, says the water body is highly polluted and action to should be taken to clean it up immediately.

“We tested the samples from the lake last month. It is polluted beyond repair. If nothing is done, people living on the banks of the lake will be badly affected,” she said.

Nandini said the release of effluents discharged by industries – which have petroleum contents – and methane emitted from sewage and organic matter (due to dumping of garbage and agricultural waste) could be the reason behind the fire which hogged media headlines.

“Water entering the lake is not treated. The effluents coming into the lake include sewage and other decayed waste. Microbes in them can secrete acid and gases, which could be a strong reason for the fire. Add to this the petroleum contents in the effluents,” she said.

Nandini said the froth was due to high content of phosphate in the water. “Each litre of water has about 2.5 milligrams of phosphate content, which is much higher compared to the normal conditions (50 micrograms). The phosphate is due to the rampant discharge of detergents from households as well as industries,” she said.

She said the tests had found that the froth contained pathogens like e-coli, faecal streptococcus and salmonella species. Termed ‘bio areosols’, these pathogens get into the air through the froth and cause severe health problems.

“People coming in contact with it will have harmful effects on their health. They will develop skin diseases. If the pathogens settle on food, the lungs of people who consume it will be affected. Even cattle are not spared,” Nandini said.

The study says all these developments will lead to algal bloom in Belandur lake and the entire ecology of the water body will be suffer serious damage if no steps are taken to clean it.