"My roots are why I work in water, directing my discoveries for those whose struggles were my own"

Can you tell us briefly about your career path and how you became involved in water research?

I grew up in a village, where we first got electricity when I was 21 years old. We lived with kerosene lamps, and I walked four kilometres one way to school through paddy fields, barefoot, splashing water in the puddles all through the way. We were children of school teachers and had a life better than many in the village. Yet, we knew that much more had to be done to make life better for everyone. In the early days, I wanted to be a writer. I interacted with many great writers of the local language who were all neighbours, and it was them that I wanted to follow. I came to science as I got older and gradually came to realise that I enjoyed science as the writers I knew enjoyed poetry. I have come to think today that these two are the same. 

I was exploring fundamental science for long time and my science to a large extent still revolves around such topics. However, in the early 2000s, the issue of pesticides in soft drinks made me think about whether nanoparticles could help in solving the problem. That led to the discovery of pesticide degradation by nanoparticles and that was developed into a technology which was incorporated into water purifiers. That was my first patent and first technology license. Soon, that research got expanded to many areas of clean water.

In India, we have been aware of arsenic in water for over 40 years, and it is one of the most important cases of mass poisoning in history. The problem of how to build an affordable and sustainable solution has presented me with an opportunity to direct my research into something truly meaningful. Clean water is the most important basic necessity, and it touches upon every part of life, health, and well-being.

What does it mean for you to receive the VinFuture Special Prize for Innovators from Developing Countries?

I am so glad that my work has been recognised by the VinFuture Foundation, and it was an honour to travel to Vietnam and receive the prize alongside esteemed innovators from across the world. It is very significant that this Prize makes a point to celebrate innovators from the developing world, whose science makes an impact. I firmly believe that, as a scientist, it is important to remember the roots, where you began in life.

The AMRIT technology removes arsenite, arsenate and iron ions and delivers clean water at an insignificant cost of $0.0003 per litre

My roots are the reason why I work in water, they are what made me work in India, made me work for the good of ordinary people, and made me direct my discoveries towards those whose struggles were my own some years ago. It was a great honour to be recognised as a scientist from a developing country, working to improve the lives of people from communities similar to mine. Today, my arsenic solution delivers 70 million litres of water daily in different parts of the country. It delivers water to about 1.3 million people in various states every day.

The International Centre for Clean Water at ITT Madras Institute was established in 2018. What is your assessment of what has been achieved in its first few years, and what are your expectations for the future?

The International Centre for Clean Water (ICCW) was established to provide an opportunity for anyone to innovate in the area of clean water. Our knowledge in technology development and translation can be used by anyone to build technologies of relevance in any society. We believe in the following objective: come with an idea and walk out with a product or a technology. ICCW has worked with many individuals and institutions to implement solutions in the field. It has created an environment in the country to appreciate issues of clean water. We have helped dozens of start-ups to expand their activities, new products to be tested in the field and several nations to link with India in the space of water.  A few start-ups have been incubated as well. There is so much more to do to create an ecosystem to innovate in the space of clean water. As water connects with every area of society, the sky is the limit for our work. We are open to everyone.

Can you tell us about nanomaterials-based AMRIT technology and how does it differ from other water filtration solutions?

AMRIT technology is an adsorption-based solution to remove arsenic and other impurities from water. Arsenic principally exists as two different ionic forms, namely arsenite and arsenate. Often water containing these ions also contains iron. The AMRIT technology removes all these ions and delivers clean water, conforming to USEPA or WHO norms at an insignificant cost of 2.5 paise ($0.0003) per litre of clean water, with all the costs (capital, consumables and maintenance) put together. The difference this technology offers is the nearly equal efficiency for both arsenate and arsenite as well as the capacity to remove soluble iron by adsorption, all at the cost mentioned. The arsenic-laden waste is safe for disposal in the field as it does not leach arsenic beyond the background levels in the field conditions. It also addresses other contaminants in water such as manganese and uranium, which are also causing issues in affected regions.

Where is AMRIT technology being used? Are there any plans to expand its use?

AMRIT is used across India. It has been approved by the nation. It has been tried in Cambodia. It has been tested in the waters of Argentina and Australia. Water quality is widely different in various parts of India, often separated by 2,000 kilometres. From such studies, we know that AMRIT can be applied in any region across the world. The technology can be expanded to any region and we are sure that it can address metal contamination anywhere.

Can you comment on other water technology solutions that your research group is working on?

We have been working on making such solutions even more sustainable. We have discovered several new materials in this context. Expanding the list of contaminants is another direction. The possibility of recovering metals from waste is another activity. We are of late interested in noble metal extraction through sustainable means. In addition, our work on contaminants has taken us to new ways of detecting them at ultra-low levels in the field using advanced materials. Besides, we work on capacitive deionisation, membrane filtration and humidity harvesting.

What do you think are some of the most pressing research needs in relation to water contamination and general water security?

We are trying to make purification run on renewable power, and have zero impact on the environment while making clean water affordable

The next ‘big idea’ in water contamination research is reducing the carbon footprint of clean water. Essentially, we are trying to make every form of water purification run on renewable power, and have zero impact on the environment while making clean water affordable. Every material we use should contribute to the circular economy. Every waste we recover from water should become a resource for the future. Solar desalination and sustainable water harvesting from the air will become affordable very soon.

Another innovative area of water research is the application of data. Tomorrow's water purifiers will become devices with predictability. Water itself is becoming data. When we supply water of particular quality, we can learn how this impacts individuals and communities over a period of time. Water data can be used to predict the health of people. Water purifiers will become intelligent devices over the course of time.

Water security will happen only with appropriate education. Society has to become water literate.