Ecotoxicogical assessment of banned and novel PFAS as individuals or in mixture

The group of per- and polyfluoroalkyl substances (PFAS) are thermally and chemically stable with strong hydrophobic and lipophobic properties, making them highly suitable for many applications. However, they are part of the emerging chemicals identified to be persistent and bioaccumulative. They are very stable, non-degradable, and present all around the world.

More than 9000 distinct individual compounds make up the PFAS group, with a carbon chain backbone between 4 and 14 C atoms in length, and a charged functional moiety: sulfonate or carboxylate.

The two principal representatives and studied PFAS (perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)) are banned in many countries, leading the major global manufacturers to find alternatives having shorter carbon chains (< C8) or with replacement chemistry with multiple ether-oxygens inserted between the perfluorinated carbon backbones, allowing the formation of non-covalent hydrogen bonds with a water molecule, which makes them more labile to degradation.

However, those new chemicals have been identified in various environmental matrices are now becoming global contaminants.

But our understanding of the PFAS alternatives toxicity is lacking in aquatic organisms and, in the case of emerging replacements and by-products, even not unexplored.

Studies assessing their potential genetic, developmental, cellular, and systemic toxicities have not yet been conducted in aquatic organisms.

To that purpose, the ECOPFAS project will investigate the acute toxicity, developmental toxicity, genotoxicity and toxicity pathways for PFAS alternatives in three freshwater species.

ECOPFAS project will build on the expertise of the researchers involved together with the acquired data to provide a basis for a better understanding of the influence of the effects on individual and population fitness to support a broader integration of these data into risk assessment frameworks.