The pollution of soil and groundwater by perfluoroalkyl and polyfluoroalkyl substances (PFAS), often referred to as ‘forever chemicals’, is one of the major environmental and health challenges of our time. In the French Ardennes, for example, residents of several municipalities have been banned from drinking tap water or using it to prepare baby bottles since July 2025.
Faced with this family of compounds, some of which are classified as ‘persistent organic pollutants and carcinogens’, how can we clean up the environment?
These substances pose a environmental pollution problem that is a real headache. The crux of the problem lies in the high costs of decontamination and the fact that current treatment techniques do not allow these compounds to be destroyed reliably and systematically without risking shifting the problem by producing other smaller and potentially equally dangerous PFAS.
Do not confuse treatment with elimination
The distinction between treating environments and eliminating (or degrading) PFAS may not be obvious, but it is nevertheless essential.
For soil and groundwater, PFAS treatment involves reducing measurable concentrations sufficiently to restore conditions as close as possible to those prior to pollution, at an acceptable technical and economic cost.
However, this treatment does not necessarily involve the degradation of PFAS, i.e. the use of physical, thermal, chemical or biological techniques to transform PFAS into less hazardous molecules.
The alternative is to extract the PFAS and concentrate them in liquid or solid residues.
However, this process is not entirely satisfactory. Although the environment is restored to its original state, the residues from the treatment can constitute a new source of pollution, or at least waste that needs to be managed.
