Water samples taken from villages in Pune, India have been found to be undrinkable following tests by laboratory scientists.
The country's Times newspaper reports that wells and bore-wells were examined in Phursungi and Urali throughout January 2009 and February 2010.
Results from the study showed contamination has risen three-fold in just a year and currently stands at 21 per cent.
Deputy director of the state health services Uddhav Gavande admitted the experiments revealed serious problems, adding: "A significant percentage of water samples from wells and bore-wells in Phursungi-Urali were found to be unfit for drinking."
Possible causes of pollution included percolation of toxic waste from refuse, with the area holding much of the civic body's garbage dumps.
Microbial and chemical contamination was discovered in 85 of the 411 samples investigated, Mr Gavande said.
The Deccan Herald recently reported that poor drinking water quality is a "serious threat" in Indian villages.