Scientists in Bangalore develop water purification system using silver

Water, however clean, provides scope for secondary contamination. Clean water gets contaminated when dirty objects come in contact with it, rendering it unclean once again, he said.

However, the bactericidal properties of silver ensure that even secondary contamination is eliminated as the bacteria are destroyed when they come in contact with silver.

Chanakya said the right proportion of silver had to be used for the best effect on bacteria and enzymes. Their experiments showed that nine gms of silver in about 1.5 kgs of clay beads or on the candle is the right proportion for both prototypes for a specific amount of water.

Astra had developed two prototypes in the laboratory. Ones with a normal candle coated with silver, while the other was with clay beads coated with silver, which acts on the water, Chanakya said.

Though laboratory prototypes have been developed, field-trials needed to be conducted to see how the people accept this passive water purification using the bactericidal properties of silver, he said.

In the ancient and medieval times, silver was extensively used all over India and Europe for water purification purpose until chlorine came on the scene, Chanakya said.

However, though chlorine is widely used in India, presently, its adverse effects have been acknowledged in the West and the developed countries who have banned its use for purifying water, he said.

“There is no policy in the country regarding clean drinking water, and we are looking at something like this which even a simple potter in a village can use for purify water at extremely low cost,” he said. With this as a background, many have come up with alternatives like mineral water and chlorinated water which did not guarantee safe water.

Copper could be a good alternative to silver as it also had similar bactericidal properties and was cheaper than the latter, he said.