The widespread use of PFAS, colloquially known as forever chemicals, has led to their accumulation in the environment and living organisms, posing serious health risks to humans. Tackling this pressing issue requires robust regulatory frameworks and reliable technologies.

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Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds that have been used on a commercial scale since the 1950s. According to the CompTox Chemical Dashboard, a chemicals database hosted by the US Environmental Protection Agency (EPA), there are over 15,000 PFAS, both with known and unknown explicit chemical structures.

The chemical structure of PFAS typically consists of multiple fluorine atoms attached to a carbon chain, rendering them resistant to chemical and thermal degradation. Furthermore, PFAS are amphiphilic – meaning they contain both water-attracting (hydrophilic) and water-repelling (hydrophobic) ends. This makes them potent surfactants and emulsifiers. Based on their size, PFAS can also be divided into two classes: polymeric and non-polymeric.   

These properties allow PFAS to be used in various products across industries, ranging from non-stick cookware, food packaging, cosmetics, to firefighting foam. However, the same properties also make PFAS difficult to break down, posing environmental risks. Indeed, due to their stability and persistence in the environment, PFAS are colloquially known as forever chemicals.

More concerningly, the prevalence of PFAS in the environment entails their accumulation in the human body, potentially resulting in adverse health effects. This has led to multiple litigations against and settlements by major PFAS producers, particularly 3M and DuPont.

Health Concerns and Exposure Routes of PFAS

Some health concerns associated with several PFAS have been known to manufacturers since the 1970s, although companies like 3M and DuPont suppressed the facts for decades, as revealed in a 2023 study by researchers at the University of California, San Francisco. Current evidence suggests that exposure to certain levels of PFAS may lead to health risks including decreased fertility, developmental delays in children, increased risk of cancer, disruption of the immune system, interference of hormones and increased risk of obesity. 

The mechanisms of these health issues are not fully understood. What is known is that PFAS are known to exert toxic effects by disrupting multiple cell signaling pathways, lipid metabolism and/or amino acid metabolism, and also binding nuclear receptors. In addition, human gut microbiomes could bioaccumulate PFAS, possibly facilitating the development of PFAS-associated health disorders.  

More concerningly, most people have PFAS in their blood on some level, as demonstrated in studies across the US, Australia, Germany, and the Netherlands, highlighting the prevalence of PFAS in human living environments. PFAS were also found in human breast milk and excreted through lactation. Human exposures to PFAS occur via routes such as ingestion, inhalation, and placental transfer. Among these, drinking water has been identified as a major source of PFAS, with clean water reservoirs and supplies worldwide commonly contaminated with PFAS. A study has also shown that PFAS are prevalent in rainwaters globally. For food exposure, fish and other seafood are the main contributors as PFAS could accumulate in their tissues.

Food and drinking water exposure routes are particularly relevant for people living near PFAS-polluting facilities and those with less access to fresh food (dependent on food wrapped in PFAS-containing packaging), demonstrating the role of socio-economic factors in PFAS-associated health risks.

The above health issues are mainly attributed to non-polymeric PFAS, particularly perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), with polymeric PFAS commonly deemed low hazard risk. However, polymeric PFAS could break down into the non-polymeric counterparts in the environment, and their production may also include non-polymeric PFAS intermediates. Hence, the entire life cycle of polymeric PFAS must be considered during the assessment of their health risks.  

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Regulations Around the World

Global regulations

Global regulations of PFAS are mainly governed by the Stockholm Convention on Persistent Organic Pollutants (POP). To date, these regulations are primarily targeted at non-polymeric PFAS, but not polymeric PFAS. An exception is the European Packaging and Packaging Waste Regulation (PPWR), which includes a restriction of 50 ppm for PFAS – including polymeric PFAS – in food packaging from August 2026. Several PFAS regulations in different countries are listed elsewhere.

Europe

In Europe, the uses of PFAS are overseen by the European Chemicals Agency under the Registration, Evaluation, Authorization and Restriction of Chemicals and POP regulations. PFOA, its salt and PFOA-related products have been banned in Europe since July 2020, with some exemptions in certain industries for a limited period. Similarly, the uses of PFOS and perfluorohexane sulfonic acid (PFHxS), their salts and related compounds have been restricted in Europe under POP regulations since 2009 and 2023, respectively. 

To highlight a specific example, PFAS levels in firefighting foams are set to 1 mg/L from October 2030, although the phased transitions allow prolonged deadlines for some applications. The legal maximum levels of PFAS in different foodstuffs have been specified, with other PFAS-related regulations relevant to the food industry having also been summarized by the European Food Safety Authority (EFSA). Furthermore, a scientific opinion published by the EFSA states that the tolerable weekly intake of PFAS – the EFSA assessment included a combination of PFOA, PFOS, perfluorononanoic acid and PFHxS – is 4.4 ng/kg body weight (bw).

More on the topic: EU Leaders Call on ‘Full Ban’ of Forever Chemicals After Testing Positive for Cancerous Pollutants

United States

Since 2024, the US EPA has designated PFOA and PFOS as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act, also known as Superfund. Furthermore, the EPA has published maximum contaminant levels for six PFAS in drinking water through the National Primary Drinking Water Regulations. Other relevant regulatory actions are listed on the registry by the Office of Information and Regulatory Affairs.

Australia and New Zealand

In Australia, the import, use, manufacture and export of PFOA, PFOS and PFHxS have been banned since July 2025 through the Industrial Chemicals Environmental Management Standard . Furthermore, the Food Standards Australia New Zealand opine that the tolerable daily intakes are 20 ng/kg bw for PFOS and 160 ng/kg bw for PFOA.

Taken together, these data indicate that non-polymeric PFAS are getting more regulated around the world, particularly in drinking water. However, there is still no consensus on the tolerable safety levels of PFAS in drinking water and/or other consumer products. In addition, discussions are on-going about whether or not polymeric PFAS – and which type of polymers – should also be regulated.

Potential Technologies to Detect or Remove PFAS

The US EPA has proposed three methods for monitoring PFAS in different environments: (1) method 1633A implements liquid chromatography-tandem mass spectrometry to test for 40 PFAS in wastewater, surface water, groundwater, soil, biosolids, sediment, landfill leachate, and fish tissue; (2) method 1621 deploys combustion ion chromatography to measure aggregate concentration of organofluorines (molecules with a carbon-fluorine bond) in wastewater; (3) OTM-50 captures volatile 30 volatile fluorinated compounds in the air by passivated stainless-steel canisters, with possible downstream analysis using gas chromatography-mass spectrometry.

For purging PFAS from the environment, particularly from drinking water, non-destructive and destructive methods have been suggested. The former involve the separation of PFAS from an environmental niche without changing their chemical structure, for example, ion-change, membrane filtration and adsorption (granular activated carbon). The latter has been used at Wilmington’s drinking-water plant in Delaware. On the other hand, destructive techniques aim to partially or completely break down PFAS by means of temperature, oxidative stress or pH, among others.