As the canton of Valais announced Monday, analyzes of five wild trout raised in the Stockalper Channel found PFAS concentrations of 42 to 159 micrograms per kilogram. This is many times over the EU limit of 8 micrograms per kilogram.
Years ago Lonza at Visp VS caused a poison scandal. Dioxane poisoned Lonza. Thousands of fish died. The substance was still detectable from 60 kilometers away.
don’t eat!
However, the canton emphasizes that most fish caught in the Stockalper Canal are grown on fish farms where they have not been exposed to any PFAS contamination. Therefore, more research will be done, including fish caught and frozen in season.
Until the results of these analyzes are available, the Canton of Valais urgently recommends that people with fish caught in the Stockalper Canal refrain from eating them until further notice. A decision will be made in March 2023 whether fishing is allowed in this channel.
Controls in the Stockalper canal have been carried out over the past two years after confirmation of strong contamination with PFAS in fish from neighboring ponds Les Chauderets in Collombey and Les Mangettes in Monthey. In fact, this canal is fed by the Canal du Bras-Neuf, which drains the groundwater and the PFAS it contains.
Extinguishing foam from a responsible old refinery?
Fishing on the Canal du Bras-Neuf has been banned since 2011 due to a previous pollution caused by polychlorinated biphenyls (PCBs) that were cured in 2014. This ban will remain in effect until the pollution situation improves.
According to the canton, PFAS pollution in Chablais groundwater is due to the use of firefighting foam at the old refinery and chemical site in Monthey. (pbe/SDA)