Scientists find way to fight 'forever chemical' lurking in your shampoo, detergent, water

BENGALURU: It sounds like something from a sci-fi film: a toxic chemical hiding in your shampoo, your detergent, and your tap water — one that conventional water treatment plants simply cannot remove. But “1,4-dioxane” is real, widespread, and very difficult to get rid of. Now, a team of Indian and Swiss researchers may have found a clever way to fight back.The chemical in question is classified as a “probable human carcinogen” by the US Environmental Protection Agency. It creeps into groundwater from industrial waste, it resists breakdown by sunlight, bacteria, and most standard water treatment methods, and it has been detected in drinking water supplies around the world. In China, a 2024 study found it in drinking water nationwide. Because it mixes completely with water and essentially refuses to leave, industries dealing with it have historically had little choice but to incinerate contaminated water — an expensive, carbon-heavy process.Researchers at Shiv Nadar Institute of Eminence in India and the University of Applied Sciences and Arts of Western Switzerland (HES-SO/Fribourg) have now published a study describing a fundamentally different approach. Rather than trying to destroy the chemical entirely — burning it up or blasting it with harsh oxidising agents — they convert it into something else. Specifically, they use blue LED light to trigger a chemical reaction that restructures 1,4-dioxane at the molecular level, transforming it into a related compound called 1,4-dioxepane, which does not mix easily with water and can therefore be physically separated out.Think of it like turning a substance that dissolves completely in your coffee into one that floats on top like oil — suddenly, skimming it off becomes straightforward.The reaction happens inside a miniature flow reactor — a palm-sized 3D-printed device with channels no wider than a few millimetres — through which contaminated water and a light-sensitive chemical reagent flow simultaneously under blue LED illumination. The device was optimised through dozens of carefully designed experiments, ultimately achieving over 93% conversion of the contaminant under realistic conditions.“Our work focuses on continuous-flow skeletal editing of 1,4-dioxane to transform it into less harmful or value-added compounds. By integrating photochemistry with microreactor technology, we achieve improved control and efficiency, offering a sustainable approach for the remediation of emerging water contaminants,” Prof Subhabrata Sen of Shiv Nadar Institute of Eminence, said. The international collaboration has drawn institutional support including the Shiv Nadar Faculty Grant for Interdisciplinary Research and Swiss partnership with Prof Ludovic Gremaud’s team at the Chemtech Institute, School of Engineering and Architecture of Fribourg (HEIA-FR), which is helping the team push the technology toward industrial use. “This partnership enables advanced reactor design, catalyst integration, and scale-up, accelerating the development of continuous, energy-efficient technologies for treating emerging water contaminants,” Professor VM Rajesh, who oversaw the reactor engineering, said.There are caveats. The reaction currently uses toluene — itself a hazardous solvent — as a carrier fluid, and the long-term environmental safety of the transformed product still needs thorough investigation. The researchers are candid about this, noting that full toxicological studies remain to be done.But in a field where “forever chemicals” have long seemed immune to affordable solutions, a blue light and a miniature reactor quietly doing the job of a treatment plant may represent exactly the kind of unglamorous breakthrough that matters most.