The first time that PFAS was discovered in Märstaån was in 2012. But despite the fact that ten years have passed, the levels are still high. This worries the County Administrative Board in Stockholm, whose task is, among other things, to protect Stockholmers’ drinking water.
– It may take a hundred years before these substances are degraded, says Johannes Knulst, environmental officer at the Stockholm County Administrative Board.
How dangerous is PFAS and the water in Märstaån? See more in the video above.
Fire foam from exercises
The environmental toxin PFAS has several different subgroups, including PFOS that was previously present in fire foam. The substance is found in the ground at Arlanda’s runways, where many firefighting exercises have been carried out. From there, it then leaks into the groundwater to Märstaån, which empties into Lake Mälaren – the county’s largest drinking water source.
No answers from Arlanda
According to the County Administrative Board, attempts are being made to limit the spread of PFAS from Arlanda Airport. SVT has contacted Swedavia, which did not answer any questions about PFAS and the work to limit the spread.