Baltic Breakfast: Difficult to contain the risk of PFAS without a ban
What was initially proposed as a ban on all uses of PFAS in the EU, may now only be a prohibition on using these chemicals in consumer products. But will this be enough? Can the risks of PFAS be contained if only some uses are banned? To answer this question, the last Baltic Breakfast seminar engaged two professors of organic chemistry; Ian Cousins from Stockholm University and Lutz Ahrens from the Swedish University of Agricultural Sciences.
The production of PFAS (per- and polyfluoroalkyl substances) took off after the Second World War, and since then thousands of substances have been used in a variety of ways, both in consumer products and industrial processes, as Ian Cousins introduces.
Problems with the substances first came to light in the early 2000s, and research into their effects intensified after widespread water contamination was discovered in Sweden and other countries around 2013. In 2015 a group of scientists, including Ian Cousins himself, got together and proposed a class-wide ban on the chemicals in the Madrid statement.
"It went surprisingly quickly from a bunch of idealistic scientists to actually come into regulation. Already in 2023 this idea of a broad restriction in the European Union was proposed by five countries," says Ian Cousins.
However, the chemical industry has resistes a broad restriction, and with a new Parliament and Commission now in place, the discussion has shifted towards a more limited ban, only on the use of PFAS in consumer products.
Large variety on PFAS
To understand the controversy around banning PFAS as a class, one has to understand the large diversity of PFAS, Ian Cousins explains.
The current definition (OECD 2021) is that any substance with one or more CF2 or CF3 moieties is a PFAS. This includes many different types of substances; solids, liquids and gases with different properties.
"Some are bioaccumulative, while some are not. Some are highly toxic, and others not that much," explains Ian Cousins.
Perhaps the most notorious PFAS is called PFOS – a persistent, bioaccumulative and toxic substance that has been listed under the Stockholm Convention since 2009.
"There is no doubt that this is a problematic substance."
But the antidepressant fluoxetine (known by the brand name Prozac) is also a PFAS, albeit with a very different behaviour, as is the polymer PTFE (known as Teflon), which is used in non-stick cookware and many other applications, such as laboratories. Yet another PFAS is the refrigerant gas hydrofluoroolefin.
"This diversity of structure and behaviour that you have within PFAS is quite different if you consider PCBs or PAH or other classes of chemicals that we have regulated before," says Ian Cousins.
Fluorinated gases most used
Fluorinated gases, which are most commonly used as refrigerants, account for the largest production volume of PFAS, measured in millions of tonnes worldwide.
The second largest production volume is that of fluoropolymers, which are mainly used in industrial processes.
"To understand why the industry is kicking back on the broad restriction is to understand the diversity, but also to understand this tonnage, because the ones they are really kicking back on are these groups, with the biggest production volumes," says Ian Cousins.
PFAS don’t break down
Despite the large variety within the PFAS, Ian Cousins assures that he still supports the Madrid statement to enact legislation to require only essential uses of PFAS.
"We don't know the toxicity or bioaccumulation behaviour of most PFAS, only a handful," he says, “but what we do know about all PFAS is that they wouldn't be in the environment if we didn't make them, they're all synthetic. They are also all very persistent because of the fluorinated carbon, which does not break down. To release something into the environment that shouldn't be there and that stays there forever: That's not good. Levels will continue to increase and if we discover problems, we can’t do anything about them.”
It has been shown numerous times that persistence is driving the problems with contamination of hazardous substances, adds Ian Cousins.
"Typically, we manufacture them for a few decades. Then we discover the problem. We talk about it for a few more decades, and then we make a decision to ban them and then they are still there in the environment."
TFA – the poster child for persistence
The poster child for the persistence problem when it comes to PFAS is the substance TFA, argues Ian Cousins. It is the smallest PFAS, containing only one fluorinated carbon, and if fluorinated gases do break down – this is what they become.
To current knowledge, the substance is not very toxic, but the levels in the environment is increasing everywhere around the world; in arctic ice cores, in tree leaves and in ground water.
"Levels are you going up all the time, and there is no way to remove it. If we discover problems, we cannot reverse it. Then we have a global problem that we cannot solve", says Ian Cousins.
Fluoropolymers – are they different?
When it comes to fluoropolymers, the manufacturers argue that they should be considered separately from other PFAS because, as polymers, they have different properties – they are inert substances that don’t bioaccumulate.
However, the life cycle of these substances is still problematic, means Ian Cousins.
The manufacturing usually causes large emissions of fluorinated gases as well as multiple by-products, and the waste management and recycling process is also concerning and connected to large knowledge gaps.
"There are a huge number of substances that are released from fluoropolymer manufacturing. Most of them are under the radar and obviously not talked about by the industry, but they are of a huge concern in my opinion."
Despite concerns about the substances that may be exempted if the PFAS ban ends up only covering consumer products, such a ban will still be a big victory, notes Ian Cousins.
"Compared to where we were a few years ago, when industry was resisting everything, this is a big step forward”, he says, adding that he will not give up on restricting also fluoropolymers and fluorinated gases.
"We know from our work that there are alternatives to many of the uses. In my view, a strong regulation of PFAS is vital and it incentivizes innovation and find alternatives."
Widespread contamination
In Europe alone, several thousands of sites are known to be contaminated by PFAS, and even more are presumed to be contaminated. A map of these sites can be seen at foreverpollution.eu/map/.
"More and more contaminated sites are discovered every day," says Lutz Ahrens, whose research is focused on contamination and on remediation methods.
A major source of this contamination is the use of firefighting foams, but PFAS are also released into the environment from industries, consumer products and waste facilities. Once in the environment, the chemicals circulate, and animals and humans are exposed to them, for example through drinking water.
One of the places in Sweden severely affected by this type of pollution is Uppsala, where PFAS containing firefighting foam has been used at the military airport Ärna for several decades. The substances have leached into the groundwater and been transported also to the raw water used in the drinking water plant in the other side of the city.
The conventional drinking water plants are not designed to remove micropollutants like PFAS, Lutz Ahrens explains, meaning that the PFAS levels in the incoming and outgoing water are basically the same. The discovery that the drinking water in Uppsala contained very high PFAS levels was done in 2012. Already the following year the National Food Agency presented new guidelines for PFAS in drinking water that included levels for seven of the PFAS known at the time.
"We were one of the first countries in Europe to have guidelines for PFAS in drinking water, because of this discovery in Uppsala," says Lutz Ahrens.
European guidelines implemented
The Swedish national guidelines were updated in 2016 to include 11 PFAS, and in 2020 the European Parliament decided on minimum regulations in member states for 20 PFAS, as well as a limit for total PFAS content. Since then, the Swedish guidelines have also been tightened, and from 2026 the limit for four PFAS (PFOA, PFNA, PFHxS and PFOS) will be set at 4 ng/litre of drinking water.
"That equals a tiny, tiny drop in an Olympic swimming pool. These levels will be very challenging for drinking water producers to fulfil," says Lutz Ahrens, adding that the raw water in Uppsala currently is exceeding that level 20 times.
"So, we have to do something or shut down the drinking water production in Uppsala."
The solution used in Uppsala today is adding an activated carbon layer to the treatment routine. The filter removes organic molecules including PFAS. However, the filter gets saturated after some months and is then transported to Germany when its being regenerated, at a high cost. Although costly, the method is working, and the PFAS levels in Uppsala drinking water is now below the threshold, both for the four PFAS of certain concern, and for a group of 21 PFAS.
"But we want to be even better, more sustainable and more cost-efficient," says Lutz Ahrens about his ongoing work to develop new techniques.
Membrane techniques effective
The current research of Lutz Ahrens and his colleagues is focused on membrane techniques, such as nanofiltration membranes and reverse osmosis. These are very effective in reducing PFAS, but results in a waste stream that also has to be taken care of. Finding methods for dealing with this waste stream and to destruct the PFAS residues is another important part of the research, as is methods for removing PFAS from soil.
"There are many possibilities for PFAS treatment, and not one single solution," says Lutz Ahrens. "All techniques have advantages and disadvantages, and typically you have to use a combination to take care of the problem."
Regardless of technique used, however, the treatment cost money. Estimations show that 20 percent of the Swedish population have been supplied water with PFAS content exceeding 10 ng /litres, and that removing this would cost more than 1,000 million SEK per year. Non-action however, also comes with a cost for health and society – about ten to fifteen times higher than the costs for treatment, according to Lutz Ahrens.
"And PFAS is just the tip of the iceberg. There are so many other pollutants that we haven’t discovered yet. So, a lot of the research we are doing right now is to find the ‘new PFAS’ -what other pollutants are we exposed to?"
"I’m glad that we can solve the drinking water issues, but there are so many animals living in the water – what about them? Are there threshold for them and can they be protected somehow?" asks moderator Ellen Bruno.
"It’s a really big problem," says Lutz Ahrens. "We have so many sources of PFAS and they are continuously released into the environment. We need better guidelines for what is allowed to release into the environment. Under the Water Framework Directive, there are EQS values for some PFAS, which are very strict limits that we exceed at many sites, but no action is required."
Ellen Bruno also asked what the researchers would do about the problem if they could decide for themselves.
"I want to ban all PFAS in products and then start taking care of all the hotspot areas we have," says Lutz Ahrens. "We need policy guidelines for the levels in soil and groundwater. Then we can start remediating these sites."
"Ny mission has been for some years now to ban all uses of PFAS, except some essential uses," says Ian Cousins. "There are some uses which can be tricky to phase out, but there are not many, I think. Most PFAS can be phased out and there are alternatives that work well. If there is a will there is a way, I’m sure."
Text: Lisa Bergqvist
Watch a recording of the seminar
Last updated: March 25, 2025
Source: Baltic Sea Centre