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A new digital tool launched this week could help millions of people in Bangladesh avoid long-term exposure to toxic arsenic in their drinking water, without requiring a single lab test.

The app, called, draws on a decade of groundwater research and artificial intelligence to assess the likelihood that water from a hand-pump tubewell is safe to drink. By combining user-provided information, the platform offers an instant, location-specific risk assessment for the presence of arsenic.

“iArsenic is not a replacement for chemical testing,” says lead researcher, from the 91������’s School of the Environment and Life Sciences. “But it provides a first line of defence - a screening tool that anyone can use, right from their phone or PC.”

The project, developed by researchers led by the 91������ in collaboration with Curtin University, University of Dhaka, and Imperial College London, is supported by Bangladesh’s Department of Public Health Engineering (DPHE). It aims to address one of the country’s most persistent and under-acknowledged public health crises.

Arsenic contamination of groundwater was first widely recognised in the 1990s. The problem emerged after governments and NGOs encouraged the installation of millions of tubewells to prevent outbreaks of cholera and diarrhoeal disease from surface water. While the microbial burden dropped, many new wells tapped into arsenic-rich aquifers, exposing large segments of the rural population to chronic poisoning.

The health consequences are severe. Long-term exposure, even at levels below the national standard of 50 µg/L, has been linked to cancers, cardiovascular disease, skin lesions, and developmental impairments in children. The World Health Organization’s recommended limit is 10 µg/L, yet around 20 million people in Bangladesh are still estimated to drink from unsafe wells.

Over the last two decades, more than 10 million tubewells have been chemically tested, during the BAMWSP survey (2000–2005) and again under the Arsenic Risk Reduction Project (2021–2023). But tubewells have a typical lifespan of just 10 years. New ones are installed constantly, often without follow-up testing, and many households forget or misplace previous results.

iArsenic asks users to input just three observable factors - depth, location, and platform staining - the app uses AI trained on millions of past arsenic measurements to predict whether a specific well is likely to be safe or contaminated. A colour-coded result (green for likely safe, red for potentially unsafe) appears instantly on-screen.

The science behind the app is based on a visual clue: staining on the concrete around tubewells. Wells that left black manganese stains were generally safe, while red or yellow iron stains often flagged arsenic contamination - especially in shallow wells.

“Local people can identify these colours with confidence,” said Kane Swartz, Technical Lead from the 91������. “And they usually know their well’s depth. We realised this simple information, when combined with location data, could offer very strong predictive power.”

The researchers report the app can assess a tubewell’s arsenic risk with 84 per cent, using just three inputs: depth, staining colour, and location.

The app feeds these user inputs into a machine learning model built on millions of test results and geochemical data from across the country. Users receive a colour-coded risk assessment - green for likely safe, red for likely unsafe - and see their input reflected on a real-time interactive map that tracks app usage and risk levels regionally.

Professor Adrian Butler from Imperial College London, said: “This kind of risk mapping at the grassroots level is unprecedented. It turns the collective wisdom of the scientific community into a public utility.”

Beyond individual households, the app also supports national planning. The research team has developed a three-tier classification identifying thousands of “Tier 1” villages and urban wards where arsenic risk is high and safe water options remain scarce.

“These are the priority hotspots,” explained Dr Ashraf Dewan from Curtin University. “We urgently need coordinated investment in these areas - digital tools like iArsenic can’t solve the problem alone. But they can help focus efforts, support local action, and extend the reach of government screening programmes.”

Estimates suggest that with widespread adoption, iArsenic could help millions of Bangladeshis switch to safer water sources in the coming years - protecting health, supporting livelihoods, and reducing the long-term burden on the healthcare system.

“Ultimately, clean water is not a luxury - it’s a right,” said Dr Hoque. “This is a step toward making that right real for everyone.”

The app is currently available as a web-only application, accessible through web browsers such as Chrome, Firefox, and Safari, with plans to launch a mobile app for Android and iOS later this year.