An experimental carbon‑capture alga unleashed by a private contractor has smothered more than 12,300 hectares (30,400 acres) of farmland in central France, killed fish in stretches of the Loire and prompted an urgent criminal investigation, officials said on Monday 21 September 2026. The product, sold as a rapid‑response “biological sponge” intended to trap riverine carbon and sediments after summer floods, formed dense, anoxic mats within days of deployment and spread onto neighbouring vineyards and orchards.
Local authorities in the departments of Indre‑et‑Loire, Maine‑et‑Loire and the Vendée closed 42 municipal water intakes, ordered the destruction of contaminated produce and banned fishing after reports of respiratory irritation among residents. Preliminary damage estimates from the regional agricultural chamber put insured losses at around €320 million (about $350 million) and warned that the true economic hit, including lost tourist revenue and long‑term soil damage, could be far higher.
The product was produced by TriZero Biologics (a private company contracted by France’s Rapid Response Agency) and marketed under the name AquaSorb‑CX. Company documents leaked to regional media and confirmed to this newspaper show a rushed emergency authorisation issued on 17 September after a three‑day environmental assessment — a timeline critics call dangerously short. “We watched our harvest literally melt into slime overnight,” said Cristofor Mirea, a third‑generation winemaker near Saumur. “This is not innovation, it’s chemical warfare on our livelihoods.”
Scientists who have examined samples say AquaSorb‑CX — an engineered consortium of algae and cellulose‑binding proteins — behaved unpredictably in warm, low‑flow conditions following the late‑summer heatwave. “Under the temperature and nutrient conditions in the Loire last week the material aggregated and blocked oxygen exchange,” said Prof. Lucine Marceau of the Institut National d'Écologie, whose team analysed river samples. “That led to catastrophic anoxia for fish and created a viscous biofilm that adhered to leaves and fruit. The product clearly was never stress‑tested for field conditions of this kind.”
Former contractors are now alleging internal pressure to deploy the product ahead of more extensive trials. “We were told to cut corners to meet delivery dates,” said Brian Koster, who resigned from TriZero last month and shared internal emails with prosecutors. “There was a document that explicitly marked long‑term ecotoxicology as ‘post‑deployment monitoring’. That’s not how you protect people or the environment.” TriZero issued a brief statement saying it was “collaborating with authorities” and had acted under a valid emergency permit; the company declined to answer detailed questions about trial data or why accelerated approval was granted.
The government moved quickly on Monday to distance itself. Élodie Garnier, minister for the environment, suspended all Rapid Response Agency‑issued permits for live biological releases and ordered an immediate freeze on commercial uses of AquaSorb‑CX while a prosecutor in Tours opens a probe into possible “endangering of the environment” and violations of chemical‑safety law. Senators from three political groups demanded hearings and an independent parliamentary inquiry; farmers’ unions called for full compensation and criminal charges. “If public safety was traded for private profit, those responsible must pay,” said Hendrik Engel‑Beer, head of a growers’ cooperative in Angers.
The incident has wider ramifications across Europe. The European Climate Commission issued a regional alert to river basin authorities and urged member states to reassess private deployment of engineered organisms in public waterways. NGOs and leading ecologists are pressing for a moratorium on commercial releases pending a Europe‑wide audit. “This is exactly why many of us have been warning against private firms controlling geoengineering tools,” said Andrea Rácová‑Pražáková, director of a Loire watershed action group. “Regulators rushed, a company profited and communities are now paying the price.” For now, clean‑up crews in rubber waders are scraping sticky mats from hedgerows and winemakers face the long task of salvaging or replanting vines, as anger at the hasty roll‑out turns to calls for nationalisation of emergency environmental tools.
