A new handheld device puts water testing into the hands of everyday people—helping communities detect toxic lead contamination before it harms their health.
Key Points at a Glance
- The E-Tongue sensor allows fast, accurate at-home lead detection in tap water
- A smartphone app provides instant color-coded safety alerts
- The device’s performance matches traditional lab-based testing
- Citizen science trials revealed elevated lead levels in 10 of 634 samples
Lead in drinking water remains one of the most pressing and underreported threats to public health—especially in communities relying on aging plumbing systems. But thanks to a breakthrough from researchers at the University of Massachusetts, families may soon be able to test their own water, right from the kitchen sink.
The innovation, described in the journal ACS Omega, is called the E-Tongue: a handheld voltammetric sensor that detects lead ions quickly, accurately, and affordably. Powered by a simple smartphone app, the E-Tongue gives users an instant, color-coded readout showing whether their water exceeds EPA safety standards.
“We wanted to put power into the hands of people,” says principal investigator Pradeep Kurup. “The reality is, many families could be unknowingly drinking contaminated water. This device gives them immediate insight—and the ability to act.”
Traditional testing methods require sending samples to specialized labs, often costing time and money. The E-Tongue changes that. Users mix a small water sample with a buffer solution, dip the sensor in, and follow three simple app commands: start, run, and end. If lead is present above 10 parts per billion—the EPA’s regulatory threshold—the screen turns red and the result is saved and shared with researchers or local authorities.
To validate the device, the team ran a citizen science trial across four towns in Massachusetts. Over 300 residents participated, collecting a total of 634 water samples. Of those, 10 tested above the EPA’s safety limit—and every positive detection was confirmed by a certified laboratory. Many other samples hovered just below the threshold, highlighting the continued need for routine monitoring.
“We’ve shown that community members can reliably collect and interpret water quality data using the E-Tongue,” Kurup explains. “That opens the door to scalable, grassroots monitoring in areas most at risk.”
The sensor’s core functionality lies in its gold electrode. When voltage is applied, lead ions attach to the sensor’s surface. Then, by reversing the current, the lead detaches, generating a signal that corresponds to the concentration level in the sample. This electrochemical approach is both highly sensitive and cost-effective.
Researchers see potential beyond just lead. The technology can be adapted to detect other heavy metals and contaminants—extending its usefulness to rural, underserved, and environmentally burdened communities. In an era of aging infrastructure and growing mistrust in public systems, the E-Tongue offers not just a diagnostic tool, but a means of empowerment.
With backing from the National Science Foundation, the team hopes to expand trials, improve design, and bring the device to market. For now, the message is clear: safe water starts with informed communities—and a simple sensor could make all the difference.
Source: American Chemical Society
