PFAS: the forever chemicals in Luxembourg's water

PFAS (per- and polyfluoroalkyl substances) comprise more than 10,000 synthetic compounds used since the 1950s for their non-stick, grease-resistant and waterproof properties: Teflon pans, food packaging, firefighting foams, textiles. Nicknamed "forever chemicals" because their carbon-fluorine bond is one of the most stable known, they persist in the environment for decades.

The European Drinking Water Directive 2020/2184 has, since January 2026, imposed a combined limit of 100 ng/L for 20 PFAS in tap water. Luxembourg, like all Member States, must now actively monitor these compounds. Several recent studies have detected PFAS in surface water and certain European catchments, at varying concentrations.

PFAS are bioaccumulative (they build up in the body). Research links chronic exposure to effects on the liver, the immune system and fertility, and to an increased risk of certain cancers (kidney, testicle). ANSES and EFSA recommend limiting exposure as much as possible.

At household level, the only effective technologies are reverse osmosis (removal > 95%), activated carbon (removal of 30–80% depending on the filter and the PFAS) and specific ion exchange. An under-sink reverse-osmosis unit remains the benchmark solution for drinking and cooking water, guaranteeing water free of almost all PFAS and other micropollutants.

The Water Management Administration publishes analyses of substances on the European watchlist in surface water. These data do not directly reflect tap water, but they make it possible to track the presence of PFAS in Luxembourg's environment. Direct monitoring at the tap outlet is currently being rolled out nationwide.