Short explainer video: how PFAS get into water, what a detection limit means and what the laboratory finding says about Piz Sardona. With a full transcript.
Published in October 2026
Read the articleTranscript
PFAS in water: what a laboratory analysis shows, and what it does not.
PFAS are synthetic chemicals that barely break down, hence the name ‘forever chemicals’. Whatever has once been released stays: in the air, in soils, in bodies of water.
The routes of entry lie at the surface: industrial waste water, firefighting foams, coated textiles and papers, sewage sludge on farmland. Some of it comes down again elsewhere with the precipitation. Water tapped today seeped into the ground years or decades ago.
A laboratory never measures ‘everything’. It looks for a defined selection of compounds, with a defined method, in a specific sample.
Every method has a limit of detection. ‘No traces could be detected’ means: what was looked for lay below it. That is not the same as ‘not present’.
For Piz Sardona, the independent laboratory SGS Institut Fresenius has confirmed in writing that no traces of PFAS could be detected.
The water of the Castels spring seeps into the ground in an area above 2,000 metres above sea level and travels through the rock for around twelve years. Origin describes that path. It does not replace a measurement.
Find out more in the Piz Sardona Academy.
More explainer videos
Piz Sardona
Alkaline mineral water with a pH of 8.0 from the Castels spring in Mels — filtered through the rock of the Sardona Alps for twelve years.
Our water