PFAS, the so-called ‘forever chemicals’, are non-degradable and widespread in everyday products – despite their known health risks. As regulatory action often lags behind, civil lawsuits are playing an increasingly important role in addressing environmental toxins. An interdisciplinary approach reveals: lasting solutions will require cooperation between science, law, and policy.
By Hanna Gabriel
🛈 In a Nutshell
- PFAS are ‘forever chemicals’ – highly persistent, mobile, and toxic substances that accumulate in the environment and the human body, leading to health problems such as cancer.
- The vast number of PFAS compounds makes traditional substance-by-substance regulation ineffective.
- PFAS lawsuits under private law are becoming an important means of holding polluters to account when regulation fails or comes too late.
- In addition, the European Chemicals Agency (ECHA) is considering a group restriction on PFAS.
- Interdisciplinary research, for example between chemistry and law, can help develop more effective and future-proof regulations for harmful substances.
Ronneby, a small town in southern Sweden, became the setting for a landmark Supreme Court ruling in 2023. Over 150 residents filed a lawsuit against the municipal water supplier after elevated levels of PFAS (per- and polyfluoroalkyl substances) were detected in their blood. PFAS are highly persistent industrial chemicals (in this case originating from firefighting foam used in drills at a nearby military site) that have been linked to diseases such as cancer. The court ruled that elevated PFAS levels in the blood constituted sufficient harm, even in the absence of a diagnosed illness. A verdict that puts pressure on the industry and could have far-reaching consequences.
Miracle compounds and an environmental nightmare
PFAS, a group of over 16,000 substances, are known as ‘forever chemicals’ for good reason. Their molecular structure, consisting of carbon chains bonded to fluorine atoms, makes them almost impossible to break down. They are mobile, for example passing through wastewater treatment systems. And some PFAS are considered highly toxic as they have been associated with various health problems, including testicular and kidney cancers, liver damage, thyroid disease, and reproductive and developmental effects. These traits classify them as ‘PMT substances’: persistent, mobile and toxic.
“On the other side, from a purely chemical perspective, PFAS are fantastic compounds. They are grease-repellent, water-repellent and ultra-heat-resistant,” says environmental chemist Thilo Hofmann, Professor of Environmental Geosciences and Co-Director of the Environment and Climate Research Hub (ECH) of the University of Vienna. “This is why they are used in many everyday items, such as sofa covers, carpets, waterproof and breathable outdoor jackets, cosmetics, toilet paper, food packaging, as well as in non-stick frying pans. PFAS are also frequently used in medical applications, for example in heart catheters to ensure they glide smoothly through the vessels.”
When the law can’t keep up
But why are PFAS not adequately covered by government regulations? This question is on the minds of citizens, NGOs, and scientists alike. The answer is simple: there are just too many of them. And each slight variation in structure escapes narrow, substance-specific restrictions. “Depending on the definition, there are 16,000 or up to one million compounds – in any case, an unmanageably large number that cannot be tested substance by substance in a reasonable amount of time,” says Hofmann. “We’ve reached the end of the line with PFAS. They highlight the fundamental dilemma of current regulations that address substances individually.”
In a related field of research, Hofmann’s colleague and legal scholar, Stephanie Nitsch, is exploring the potential of private law to complement government regulation. She is a tenure-track professor of comparative private law, specialising in private environmental law, and also a member of the ECH.
According to Nitsch, increasingly plaintiffs rest their claims on private law: “Because liability law of a private law nature is formulated in general terms, it is more versatile. Unlike precise restrictions or prohibitions, it doesn’t rely on narrowly defined rules, but on broadly worded general clauses.” Another consequence is that in private law civil courts, not administrative authorities, examine the liability requirements in each individual case. “Judges are highly qualified experts who are adept at recognising the nuances between individual cases.”
When private law steps in
“In the Swedish case with elevated PFAS in drinking water, the ruling was based on product liability, which is one of the sharpest liability standards under European law as it doesn’t require proof of fault” says Nitsch. In other words: The manufacturer – or, in this case, the water provider – is held liable for their product even if it wasn’t their fault the PFAS ended up in the water.
Across the US and increasingly in Europe, PFAS litigation is becoming a powerful legal instrument for individuals and NGOs. Lawsuits are expected to reach ‘astronomical’ sums, the New York Times reports, potentially exceeding even the financial records of asbestos litigation. Stephanie Nitsch explains: “The aim of strategic litigation is not just to address an individual concern, but to effect broader societal change. In such lawsuits, it’s unclear whether there is any real chance of success, but they help raise public awareness”. In this way, private law is emerging as a complementary force to public regulation, especially given the slow pace of legislative processes.
A group ban in the making
In recognition of these limitations, five EU member states submitted a joint proposal to the European Chemicals Agency (ECHA) in 2023 for a group restriction on PFAS. They argue that a total PFAS ban is essential to prevent an estimated 4.4 million tonnes of PFAS being released into the environment over the next 30 years.
Given the widespread use of PFAS, they have proposed transition periods depending on the application: For food contact materials, for example, where alternatives are already being developed, the transition period is five years. For implantable medical devices, for which alternatives have yet to be found, the proposed transition period is 12 years.
A decision on the proposal is expected in late 2025. If implemented, this would represent a fundamental break with the established substance-by-substance framework.
Good intentions, bad outcomes
But is a total ban really the answer? According to environmental chemist Hofmann, TFA (trifluoroacetic acid) is one of the most pressing cases, because it already exceeds the limit values in rainwater. TFAs are a type of PFAS and are also a degradation product of various PFAS compounds, such as fluorinated pesticides.
The irony is that, in the past, banning a substance often led to the introduction of new ones that were just as toxic. “It’s the same pattern every time – be it petroleum, tobacco, or pesticides. Even PFAS-containing refrigerants, such as hydrofluoroolefins or HFOs, were originally introduced as an alternative to ozone-depleting CFCs, or chlorofluorocarbons. Now, decades later, we’re realising that these novel ‘ozone-friendly’ refrigerants break down in the atmosphere to form TFA. They are quite literally raining down on us,” warns environmental chemist Hofmann. Another striking example is plastic straws. “The EU banned them with the best of intentions – but now over 90 per cent of the paper straws on the market are coated with PFAS to make them more durable.”
In light of the health risks associated with PFAS, Hofmann argues that a PFAS ban is inevitable. “We’re now finding such high concentrations of TFA and other PFAS in rainwater that they already exceed regulatory limits, particularly in coastal regions such as Denmark, the Netherlands and northern Germany. Just think about what that means: In principle, it implies that no one should be allowed to drink the groundwater.” In addition to rainwater, environmental pollution with ‘forever chemicals’ is evident in reports of rising TFA concentrations in foodstuffs such as wine, vegetables, fruit and flour.
A shift in chemical thinking
At the root of the PFAS dilemma lies not just a legal failure, but also an academic one. “I think there needs to be a profound rethink in chemistry. In the past, green chemistry wasn’t part of the curriculum, and it was seen as an attack on the profession to suggest that what we produce might be harmful,” Hofmann recalls. Now, it is slowly becoming the norm that substances must be designed to be both safe and sustainable.
Institutions like the Environment and Climate Research Hub (ECH), which brings together leading researchers from the natural sciences, law, economics, and the humanities to tackle environmental challenges, are playing a key role in such transitions. “The strength of the ECH lies in how it connects perspectives,” says Nitsch. In doing so, it supports interdisciplinary climate research that is not a fragmented effort.
Using law as leverage
Back in the courtroom, the legal push continues. And it is not without complexity, as Nitsch explains: “Whether a case succeeds depends on many factors: the specific pollutant, the defendant, the state of scientific knowledge, and even the public’s awareness.” She also cautions: “This is not about shifting responsibility from the state to individuals. It’s about testing whether private law can fill gaps when regulation lags behind.”
Today, Ronneby in Sweden is known as the world’s worst case of PFAS contamination, and its residents are still gathering evidence for their lawsuit. It may take years before they reach a resolution. But the larger question remains: How long will it take to re-invent the regulatory system itself?
About the researchers
Thilo Hofmann is an environmental chemist and head of the research platform ‘Plastics in the Environment and Society’ as well as Co-Director of the Environment and Climate Research Hub (ECH) of the University of Vienna. His research focuses on the environmental fate of emerging contaminants and aims to develop practical solutions to pollution-related challenges. His current work centers on ‘forever chemicals’ such as PFAS, plastic pollution, agricultural contaminants, tire wear particles, and chemical additives of concern. Hofmann has received numerous awards, including from the German Academic Scholarship Foundation, TU Berlin, and the German Water Chemical Society. He is adjunct/visiting professor at Duke University (USA) and Nankai University (China). His recent publications include studies on tire abrasion in coastal waters and rubber particle inhalation from climbing shoes.
Stephanie Nitsch is a tenure-track professor of comparative private law with a special focus on environmental private law at the University of Vienna. She heads the university’s Environmental Law Research Unit and is a member of the Environment and Climate Research Hub (ECH). Her research explores how private law can support environmental protection and collective interests. With her research projects, Nitsch covers topics such as liability for environmental harm (e.g., PFAS litigation, microplastics and climate change litigation), supply chain responsibility, legal remedies against greenwashing, and housing law in the context of climate transition. A current ECH-funded project investigates how scientific evidence can be translated into legal proceedings (From Lab to Litigation).
