PFAS: Per- and polyfluorinated alkyl substances in food

Steadily improvement of PFAS analysis method

Per- and polyfluorinated alkyl substances (PFAS), which include PFOS (perfluorooctanesulfonic acid) and PFOA (perfluorooctanoic acid), are persistent organic pollutants (POPs) that can reach us humans through the food chain. This class of contaminants has been in focus of the European Food Safety Authority (EFSA) for several years. In the EU, maximum levels for selected PFAS in certain foods have now come into force for the first time, taking effect from 1 January 2023. The Competence Centre for Dioxins & Persistent Organic Compounds (POPs) of the Eurofins Laboratory Network for Food & Feed Testing in Germany is continuously optimising its analytical methods and limits of quantification. Thus, almost the complete parameter range of EU Recommendation 2022/1431 can now be determined in foodstuffs.

EU projects on PFAS in food

After the EFSA has established a group TWI (tolerable weekly intake) in 2020 for the four PFAS compounds listed below

• perfluorooctane sulfonic acid (PFOS)
• perfluorooctanoic acid (PFOA)
• perfluorononanoic acid (PFNA)
• perfluorohexanesulfonic acid (PFHxS)

(see our article: Per- and polyfluorinated alkyl substances (PFAS) are increasingly in the spotlight), further work at EU level continued to address this group of contaminants, divided into three sub-projects:

• Introduction of maximum levels in certain foods of animal origin (SANTE/11183/2018)
• Establishment of monitoring recommendations for food (and feed) with "indicative levels" for certain products (SANTE 2021-10010)
• Establishment of specifications for the control of PFAS in food (sampling and analysis) (SANTE 11354-2021)

The work on all three sub-projects has now been translated into legally valid EU documents.

More comprehensive monitoring of PFAS in food by EU Member States

In accordance with Commission Recommendation (EU) 2022/1431 of 24 August 2022 on the monitoring of perfluoroalkyl substances in food (OJ L 221, 26.8.2022, p. 105), EU Member States, in collaboration with food business operators, should monitor during the years 2022, 2023, 2024 and 2025 the presence of PFAS in food and collect more comprehensive data for monitoring perfluoroalkyl substances in food. The recommendation takes into account not only EFSA's four priority PFAS mentioned above (PFOS, PFOA, PFHxS and PFNA), but also a large number of other PFAS, which are now almost completely part of the analysable portfolio of the Competence Centre for Dioxins & Persistent Organic Compounds (POPs) of Eurofins Laboratories for Food and Feed Analysis in Germany.

The recommendation for monitoring refers to a much wider range of foods. The monitoring is intended to cover a wide range of foods that correspond to consumption habits, including fruits, vegetables, starchy roots and tubers, mushrooms, seaweed, cereals, nuts, oilseeds, food for infants and young children, food of animal origin, non-alcoholic drinks, wine and beer.

The recommendation also includes indicative levels, above which further investigations of the causes of contamination should be carried out:

Table 2: Indicative levels of PFAS in food

A subsequent re-evaluation of the PFAS pollutant group by EFSA following this monitoring is expected.

Legal requirements for sampling methods and methods of analysis for the official control of PFAS

Sampling and analyses for the official control of levels of PFAS in foodstuffs for which maximum levels have been set in Regulation (EU) 2023/915 shall be carried out in accordance with the provisions laid down in Commission Implementing Regulation (EU) 2022/1428 of 24 August 2022 laying down methods of sampling and analysis for the control of perfluoroalkyl substances in certain foodstuffs (OJ L 2022, 26.8.2022, p. 66).

Although the requirements of this implementing regulation directly concern the analysis of officially taken food samples only, the competence center for dioxins & persistent organic compounds of the Eurofins Food & Feed Testing laboratories in Germany is guided by these requirements in order to ensure comparability of the analytical results of officially taken samples and samples taken within the self-monitoring of food business operators.

Challenges for food and feed producers: Raw material selection

For food and feed producers, raw material selection can be challenging, especially around a source of contamination known as a "hot spot."

PFAS have been and are still deliberately processed by humans and used in a variety of industries worldwide (e.g., textiles, household products, firefighting, automotive, food processing, construction, electronics). The Organization for Economic Cooperation and Development (OECD) estimates that more than 4700 different PFAS compounds have been technically synthesised to date. This variability in compounds and application fields leads to a variety of input pathways into the environment, which are shown in the figure below:

Fig. 1: Entry and transport of PFAS in the environment

Eurofins Competence Centre continues to improve its analytical method for PFAS in food

The desired or required limits of quantification in the documents published by the EU are a challenge for many laboratories. Since PFAS are ubiquitously distributed in the environment, influences of blank values in the lab must be avoided, reduced and carefully controlled. These influences of blank values, in addition to other factors, also determine the achievable limits of quantification.

It should also be possible to cover the multitude of PFAS parameters of Recommendation 2022/1431 with their different chemical properties as efficiently as possible by one analytical method.

The competence center for dioxins & persistent organic compounds of the Eurofins Food & Feed Testing laboratories in Germany closely follows developments in the field of environmental contaminants and is constantly working on improving existing analytical methods in terms of measurement capacities, parameter scope and measurement sensitivity. Our analytical methods achieve the requirements for limits of quantification specified in Recommendation 2022/1431 and almost completely cover the PFAS parameter scope for monitoring.

Table 3: EU requirements according to Recommendation 2022/1431 and current limits of quantification for PFAS at Eurofins GfA Lab Service GmbH

Even though continuous improvements in the analytical method have already led to an outstanding measurement sensitivity in the determination of PFAS, our experts will continue to work on further improving analytical methods in terms of sensitivity as well as adding PFAS compounds to the portfolio of analysable parameters.

Outlook

Developments in analytical methods may change regulatory approaches by authorities in the future. Such developments include improvements in measurement sensitivity or expansion of the number of analysable parameters for the targeted detection of PFAS.

The issue of PFASs is thus likely to become a long-term focus of the controlling authorities, analogous to dioxins and PCBs, and to influence the risk assessment for food and feed production.

Consulting and analytical services by our experts

Do you have any questions regarding persistent organic pollutants (POPs) like PFAS or our analytical methods? For further questions do not hesitate to turn to your personal account manager or contact our experts directly.

Other interesting pages