© Diana Hoffmann / RTL
Forever chemicals, also known as PFAS, pose a significant challenge to European waters. The EU is set to introduce limit values from 2026.
An increasingly large issue for the environment, PFAS are "organofluorine carbon compounds. These are substances that we find in everyday life, everywhere where special properties are required. They have anti-stick properties, but also beading properties", explains Brigitte Lambert, the unit head at the Water Management Office.
Among other uses, PFAS are used in the production of Teflon pans, cosmetics, medication, and waterproof clothing. They are also found in the breakdown of selected fluorine-based pesticides. The issue with these chemical compounds, however, is that they rarely break down and are therefore virtually omnipresent in nature, as well as our drinking water.
The Water Management Office's laboratory in Belval carries out regular analysis on the PFAS found in Luxembourgish water. "In Luxembourg, we have a relatively low concentration of PFAs", says Lambert. "This is different to other countries, which have certain industrial hotspots where the PFAS exceed the limit of 100 nanogrammes. We don't have this in Luxembourg."
From 2026, the EU will introduce limits to PFAS, although the Grand Duchy has applied these limits since 2023.
Currently, the sum of the 20 most important PFAS is not meant to exceed 100 nanogrammes per litre of drinking water. This represents a volume of seven grains of rice in an Olympic-sized swimming pool. The average value of these 20 PFAs analysed in drinking water currently stands at 1.2 nanogrammes per litre.
Furthermore, the sum of all PFAS in drinking water may not surpass the limit of 500 nanogrammes per litre. However, it is difficult to analyse this in full, as many of the 10,000 substances belonging to the PFA classification have not been researched, says Lambert.
A more special role is assigned to the forever chemical TFA. TFA stands for trifluoroacetic acid, an artificially produced chemical that hardly, if at all, degrades in nature. There is no legal limit here, but only a guideline value of 12,000 nanogrammes per litre.
Currently, the average value of TFA in drinking water in the Grand Duchy is 850 nanogrammes. TFA is a very small PFAS molecule. “It has been observed that it accumulates less in the human body. In the few studies that have been conducted so far, it also seems to be less toxic than, for example, PFOA”, explains Laurence Wurth from the Health Directorate.
Purifying drinking water at SEBES
SEBES in Eschdorf is responsible for turning water from the Upper Sûre Lake reservoir into drinking water. The lake supplies 50-70% of the country with drinking water, which must first be treated. "We have to remove PFAS with ozonation and activated carbon filtration", explains SEBES director Georges Kraus. "But this isn't so easy with TFAs. The molecules aren't solid, they are dissolved. And our treatment cannot effectively remove them." Although they are theoretically able to be removed, it requires a large investment to produce what is effectively distilled water.
Kraus says he would be glad if Luxembourg could go a step further and ban products based on PFAS and TFAs. "This would mean they could no longer form in nature if they were no longer used", he adds. But it is still relatively unclear where the global PFA contamination in drinking water comes from.
For Luxembourg, however, the Mouvement Ecologique says it is clear in rural areas that TFAs come from selected pesticides, as it is a known byproduct of pesticide degradation. Other countries have banned these pesticides, explains Claire Wolff of the environmental group, as they have been shown to potentially pose a risk to human health.
"We are calling for a precautionary principle, as these are forever chemicals, they will remain in nature forever, so we have to stop them from entering now. Otherwise we could reach a point of no return and we won't be able to improve the situation", Wolff says.
