150 participants from authorities, science, industry and environmental organisations discussed the risks of perfluorinated and polyfluorinated alkyl substances (PFAS) in soils at the Federal Press Office in Berlin. 200 people from 26 countries followed the conference via live stream. More international cooperation is needed to effectively counter the worldwide spread and global risks.
Per- and polyfluorinated alkyl substances (PFAS) find their way into drinking water, plants and processed foods via soils and thus into the human body. They are called forever chemicals because they are extremely persistent and can hardly be degraded under environmental conditions. At the conference, the topic of PFAS in soils was discussed in four sessions from different perspectives. The programme is available on the website: Conference PFAS in soil - forever pollution, forever concern? Start | Umweltbundesamt
The event, jointly organised by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV) and the Federal Environment Agency (UBA), was opened by State Secretary Christiane Rohleder and Prof. Dr. Claudia Röhl, Head of the ‘Environmental Health, Protection of Ecosystems’ Division. UBA President Prof Dr Dirk Messner chaired a high-level panel discussion.
Case studies - PFAS in soils and exposure pathways
The effects of PFAS on humans and the environment in areas with particularly high PFAS contamination were presented in case studies from Germany, Denmark, Sweden and France. In the contaminated agricultural areas in Rastatt (Germany), most probably due to waste from the paper industry, PFAS were introduced from the soil into the groundwater and crops, so that the drinking water was also contaminated locally. In Korsør (Denmark), the pollutants entered the food chain for years through a former fire training site via the groundwater and surrounding soil. Cattle on a nearby pasture ingested PFAS via water from a ditch and grass. As a result, high PFAS concentrations were detected in the blood of the beef consumers. In Lyon (France), elevated levels were measured in eggs from private farms. The suspected cause of this is an industrial area with a local flue chemistry. A case study from Sweden showed that the drinking water in the town of Ronneby was contaminated by military fire-fighting exercises. Another presentation focussed on studies of wild boar in Germany. PFAS accumulate in the animals, especially in the liver, so that authorities advise against eating wild boar liver.
Analysis, monitoring, remediation
The possibilities and limitations of current methods for analysing PFAS in soils were presented and discussed. Soil eluate and extract analyses are generally suitable, but differences in sample preparation - such as drying and milling - can impair comparability. The use of sum parameters can reveal PFAS contents that could not previously be determined using individual substance analyses.
Monitoring data from North Rhine-Westphalia and initial results of the Germany-wide recording of PFAS background levels were then presented. In areas where no specific PFAS contamination is known, soil samples were analysed for PFAS and detected in the topsoil across the board. In Switzerland, too, PFAS were detected in all analysed topsoil samples and occasionally in subsoil samples. In almost half of the Swiss groundwater monitoring wells analysed, PFAS were detected in mostly low concentrations. Contaminated areas are also known here due to the use of PFAS-containing extinguishing foams, among other things. In one case study, elevated PFAS levels were found in milk and meat from cattle. The contamination is thought to have been caused by sewage sludge that was last applied to the soil as fertiliser 20 years ago.
Great progress was made in the remediation of contaminated soil and groundwater. The participants discussed the possibilities and limitations of currently available methods: Soil washing and immobilisation processes, also in situ, are becoming increasingly established as effective methods for PFAS remediation. Various processes are now also available for the mineralisation of PFAS in aqueous concentrates. Nevertheless, the concentration step remains a key technical challenge. Currently, the development of in-situ barrier processes - in particular sorption in so-called funnel-and-gate systems - is increasingly coming into focus. Considerable research and development is still required to improve the economic efficiency of these technologies. In addition, there has been a lack of reliable economic feasibility studies to date, which makes the broad application of these processes difficult.
PFAS monitoring and necessary measures
The keynote speech in Session 3 highlighted the health effects of PFAS using the example of the investigations of the residents of Ronneby affected by extensive PFAS drinking water contamination. Initial results indicate, for example, an increased risk of osteoporosis fractures and an increased risk of type 2 diabetes.
Several European countries presented their strategies for dealing with PFAS pollution. Belgium's PFAS crisis started in 2021 with high PFAS findings near a Flanders chemical company. The systematic search for further PFAS damage cases led to the identification of more than 8,000 suspected sites in Flanders, which have been or will be subject to further investigations. So-called ‘no-regret zones’ are being set up in which protective measures apply until the final assessment is complete, such as consumption warnings for eggs from private holdings, for cultivated fruit and vegetables and restrictions on water use. Attention is also drawn to potentially high PFAS concentrations in house dust. If PFAS contamination is confirmed, measures will be taken in Flanders, such as precautionary soil replacement in residential areas. As the management costs are very high, the establishment of a fund is being discussed in Belgium.
France is focusing on an interministerial action plan with measures to reduce PFAS emissions, improve drinking water quality and strengthen research. Austria has launched a national PFAS action plan to identify and remediate contaminated sites. In addition, research in the field of PFAS analysis and remediation is to be intensified. In the UK, the National Environment Agency is drawing up a picture of the extent of the problem using a risk-based screening programme with data from groundwater and surface water, as well as information from approved industrial operations, local findings and third-party data (e.g. water supply companies). On this basis, an evidence-based foundation is created for further measures. The aim is to initiate voluntary or regulatory measures (e.g. licences or soil protection laws) to eliminate existing pollution. The Netherlands is working to reduce emissions from existing sources through innovative technologies and education about alternatives. Exposure to PFAS in food, drinking water and the environment is to be minimised through monitoring and the development of limit values and the remediation of contaminated sites is to be promoted. Transparency, clear liability for companies and the promotion of research and development of new technologies are seen as crucial to the success of these measures. In addition to monitoring, Denmark is focussing on the development of new methods for the remediation of contaminated sites and reports on the investment of DKK 10 million (€1.3 million) to test remediation technologies on a large scale.
Need for action at European level
Tackling the PFAS problem poses numerous challenges for politics, science and industry. UBA President Dirk Messner discussed the opportunities for increased European cooperation with Jutta Paulus (EU Parliament), Paul Speight (EU Commission), Patrik ten Brink (European Environmental Bureau) and Leen Bastiaens (Knowledge Centre on Innovative Remediation Solutions, KIS). There was agreement that preventive measures must play a key role. The use of PFAS should be strictly limited to essential applications in future in order to prevent further contamination in the future. Europe-wide PFAS monitoring was also discussed. The objectives of European cooperation should be the harmonisation of limit values, the development of better monitoring systems and the promotion of innovative remediation and safety methods.
CONCLUSION
The conference made it clear that PFAS in soil and water are a Europe-wide problem that requires consistent and coordinated action. An effective monitoring programme is essential in order to identify PFAS contamination in soil and groundwater at an early stage and initiate targeted remediation measures. The examples of European countries presented at the conference show that there are already various national approaches to dealing with the PFAS problem. In order to make better use of the findings, learn from each other, regulate in a standardised manner and establish efficient measures, greater European cooperation is required. A key outcome of the conference will be a discussion paper that summarises the necessary action steps for the political players.
