For Rs 2, E-Eye Can Check If Water Is Safe

E-Eye, which cost about Rs 3,500 to develop, can test a sample for around Rs 2, making it particularly suitable for field-level water quality monitoring in areas where access to sophisticated laboratories is limited.

A team of researchers at the Indian Institute of Technology-Guwahati has developed a low-cost portable device that can detect toxicants in water almost instantly, potentially offering a simpler and cheaper alternative to conventional laboratory-based water quality testing.

Called 'E-Eye', the device functions as an electronic eye, using optical sensing technology to identify and quantify contaminants in water and other samples.

The researchers say the device, which costs about Rs 3,500 to develop, can test a sample for around Rs 2, making it particularly suitable for field-level water quality monitoring in areas where access to sophisticated laboratories is limited.

The portable device can detect arsenic, lead, fluoride, iron, chromium and E. coli, among other contaminants, and transmit data wirelessly for remote monitoring.

A laboratory in the palm of your hand

E-Eye works by triggering a chemical reaction that produces a coloured compound when it comes into contact with a targeted contaminant.

The intensity of the resulting colour is measured optically and converted into digital data, allowing the concentration of the toxicant to be displayed in real time.

The device is based on the Beer-Lambert law, which establishes a relationship between the absorption of light by a substance and its concentration.

"Our device uses the Beer-Lambert principle to combine optical sensing with digital electronics, allowing us to obtain accurate quantitative measurements of contaminants," said Professor Tapas K Mandal of IIT Guwahati's Department of Chemical Engineering.

"During our tests, E-Eye successfully detected a range of toxicants, including arsenic, lead, iron, chromium and fluoride, as well as Escherichia coli bacteria," he added.

The device can also transmit data wirelessly to water treatment facilities, opening up the possibility of remotely tracking water quality and identifying contamination at its source.

Cheaper than conventional testing

Conventional methods of detecting contaminants often rely on sophisticated instruments such as UV-Visible spectrophotometers and Atomic Absorption Spectrophotometers, which are expensive and require specialised laboratories and trained personnel.

E-Eye, in contrast, has been designed for direct deployment in the field.

Laboratory evaluations conducted by the research team found that the portable system produced results comparable to standard laboratory equipment, while also providing digital data integration.

The researchers have tested more than 2,700 samples and reported consistently accurate results.

At an approximate development cost of Rs 3,500, the device can analyse an individual sample for around Rs 2.

The team believes the cost could fall further if the technology is manufactured on a large scale.

From drinking water to food and soil

The potential applications of E-Eye extend beyond drinking water.

According to the researchers, the device can be used to analyse environmental and biological samples as well as vegetables, food products, tea and herbal products, soil and milk.

It could also help industries monitor liquid effluents containing heavy metals, bacteria and compounds responsible for unpleasant odours.

Professor Harshal B Nemade of IIT Guwahati's Department of Electronics and Electrical Engineering said the technology could have applications across government agencies, industries and private enterprises.

"E-Eye can be useful for water quality monitoring by agencies under the Ministry of Jal Shakti, as well as for food and herbal product manufacturers," Professor Nemade said.

"Industries could also use it to check liquid effluents for heavy metals, bacteria and other compounds that cause unpleasant odours," Professor Nemade added.

A boost to water quality monitoring

The researchers believe E-Eye could be particularly useful for decentralised water quality surveillance, where samples can be tested at the source instead of being transported to laboratories.

The technology also aligns with the Centre's Jal Jeevan Mission, which seeks to improve access to safe drinking water and strengthen mechanisms for monitoring water quality.

Its relatively low operating cost could make frequent testing more feasible, particularly in rural and remote areas.

From laboratory innovation to startup

The research was supported by a grant from the ministry of electronics and information technology.

To take the technology beyond the laboratory, the researchers have established a startup, ENVIONIX Labs Pvt Ltd, and are looking to work with industry partners for technology transfer and large-scale deployment.

The research findings have been published in the IEEE Sensors Journal.

The paper was co-authored by Professor Mandal and Professor Nemade, along with IIT Guwahati Research Scholars Shrikant Kashyap, Smriti Sachan and Neha Majee, Maitrayee Bhuyan of KIIT Bhubaneswar and Humayun Kabir of the Ramakrishna Mission Residential College, Kolkata.

The next step: Solar power and the cloud

The team is now working on further improving the device by integrating solar panels so that it can operate in a self-sustaining manner.

Researchers are also developing cloud connectivity that would allow data collected by E-Eye to be monitored and managed remotely.

If successfully commercialised and deployed on a large scale, the technology could provide water authorities, industries and other users with a relatively inexpensive way of detecting contamination quickly -- without waiting for samples to reach a conventional laboratory.

Feature Presentation: Ashish Narsale/Rediff