As large crowds continued to throng the Mahim beach to drink sweet seawater for the second day, the Maharashtra government on Sunday warned people against drinking the polluted water.
Scientists clarified that the seawater had turned sweet due to the natural phenomenon of dilution.
"Dilution is a phenomenon observed all along the western coast of India during the southwest monsoon and occurs when rainwater borne by rivers mix with seawater along the coast," said MD Zingde, a scientist at the National Institute of Oceanography regional centre in Mumbai.
"The change in salinity at the Mahim creek could be attributed to the large quantities of groundwater draining into the sea because of the rains.
"The noticeable drop in salinity levels occurs at low tide when the maximum dilution of seawater by fresh water occurs. Apart from this, one must also consider that the Mithi river, too, flows into the Mahim creek," he added.
Weekend reports of the Mahim creek's water tasting sweet sparked a flood of visitors near the Baba Maqdoom Dargah to witness and partake the "miracle" water.
The Brihanmumbai Municipal Corporation (BMC) on Saturday conducted tests to establish pollutant levels in the water and warned people against waterborne diseases from consumption.
"The water in the Mahim creek is absolutely not potable. Samples of water taken from the creek showed low chloride content, which in itself is harmful. The samples contained dangerous levels of nitrates and would affect people who consume too much of the 'sweet water'," said BMC commissioner Johnny Joseph.
"The decline in salinity was mainly due to two reasons. Apart from the Mithi river flowing into the Mahim creek, water from the sweet water Vihar Lake, too, was draining into the creek, thereby reducing the salinity," Joseph said on Sunday.
Infectious disease experts have warned that drinking water with an exceptionally low chloride content will increase the risk of diarrhoea, typhoid and other maladies.
"Exceptionally low chloride content supports the growth of bacteria. Coupled with the presence of industrial effluents, drinking the water will increase the risk of diarrhoea, typhoid and other infections," said Tannu Singal, an expert on infectious diseases.
"While those who consume small amounts of this water may suffer from nausea and vomiting, which should subside in 24 hours, those who consume large quantities may contract cholera and typhoid," he added.