A spot of copper ion to make your water crystal clear

Our grandmothers knew this and in many traditional homes drinking water is still stored in copper pots. But the march of technology and affordability has replaced copper containers with refrigerators and electronic water-purifiers.

Now, researchers in Bengaluru, reaching back into the past, have come up with a simple device that uses the properties of copper ions to purify water at practically no cost. Called TamRas, or `essence of copper’, the device was launched recently by the Trans Disciplinary University (TDU). The findings were published in the Royal Society journal.

Tata Trusts backed the research work by the TDU. TamRas helps sterilise E.coli, rota virus, typhoid and cholera-causing pathogens, which are commonly found in drinking water. TamRas is easy to use, requires no electricity, no recurring maintenance cost and, just like grandma’s copper pots, can be passed on from one generation to the next — this is what actually inspired the TDU innovation.

Padma Venkat, Principal Investigator of the project, says: “We found that leaving contaminated water in copper pots overnight killed deadly pathogens like Vibrio cholerae , rotavirus and Shigella flexneri . This seemed to be a simple method to save lives. Since copper pots are expensive and difficult to maintain, we have come up with a contemporary design that works as well as the copper pot, costs a fraction and acts in double-quick time, too.”

The key advantage of of the TDU device is its sustainability. There are no filters to be maintained or replaced, or need for any purifiers like chlorine tablets. This is where TamRas scores — in not requiring any maintenance, the researchers claim.

The relevance of a device like TamRas and its potential as a public health intervention tool can be gauged from the fact that in India faecal contamination of drinking water is common, and 276 million people living below the Poverty Line cannot afford expensive solutions to purify water. Similarly, mortality of under-five children due to infectious diarrhoea, is as high as 18 per cent.

TamRas consists of a container that houses an immersible copper unit calibrated to render 15 litres of water free of pathogens when left undisturbed for 10 hours. Copper is also a micronutrient and has several physiological benefits. Therefore, the promise of TamRas is ‘More than just safe water’.

The design for TamRas was arrived at after several iterations and testing for aesthetics, compliance, convenience and cost. It will cost ₹1,500 and will be sold through a community-based social enterprise model, wherein the local entrepreneur will not just be promoting the product but also nudging behaviour change in terms of better sanitation and hygiene practices.

The TDU researchers took about eight years to develop TamRas. It has been tested by the National Institute of Cholera and Enteric Diseases and CMC Vellore for its efficacy in killing diarrhoea-causing pathogens, said Balakrishna Pisupati, Vice-Chancellor of TDU.

The Grand Challenges, Canada, Bold Ideas for Big Impact grant supported its field testing in Indian and Kenyan households.

COMMENT NOW