PFAS Modification Raises Concerns in the US

Per- and poly-fluoroalkyl substances, mostly referred to as PFAS, are part of Persistent Organic Pollutants (POPs) present in diverse consumer and industrial products. PFAS has a myriad of applications due to its increased resistance and durable characteristics. In fact, durability is the reason such chemicals are also referred to as "forever chemicals".

PFAS are substances with fluorinated atoms, which prevent the substances from being broken down and decomposing in the environment. On the contrary, PFAS bioaccumulates in organisms, and its toxicity increases over time. Consequently, organisms may present several dysfunctions during their lifetime, and ultimately lead to death. Due to the severity and difficulties of a single country controlling POPs pollution alone, the United Nations Environment Programme (UNEP) proposed an international treaty to eliminate or restrict the production and use of POPs – the Stockholm Convention.

Recently, the United States (US) Environmental Protection Agency (EPA) published the PFAS Strategic Roadmap: EPA's Commitments to Action 2021-2024, aiming to improve research, restriction, and remediation of polluted sites. However, the agency’s definition of PFAS substances in the National PFAS Testing Strategy differed drastically from the expected common description.

When US EPA refers to PFAS substances as those "chemicals with at least two adjacent carbon atoms, where one carbon is fully fluorinated and the other is at least partially fluorinated", it includes around 7 thousand substances. On the other hand, other comprehensive PFAS definitions, such as those used by the Organisation for Economic Co-operation and Development (OECD), lead to expressive higher numbers.

The difference is that OECD opted to consider PFAS as any substance containing a fully or partly fluorinated carbon chain. This opposing view on PFAS substances may be related to recent reports showing regions along the US highly contaminated with the substance. The most recent example occurred in North Carolina, where the drinking water supplies were contaminated with dozens of fluorochemicals.

Since POPs (and all chemicals under the term) are chemicals with high persistence, durability, mobility, and toxicity, it is fundamental that authorities reach a consensus to safeguard and protect the environment and human health, nationally and internationally.