Understanding the PFAS risk in food supply chains

Understanding the PFAS risk in food supply chains 

Per- and polyfluorinated substances (PFAS) are organic compounds in which hydrogen atoms are replaced by fluorine atoms. Known for their water- and grease-repellent properties, they are used in a wide variety of products, such as firefighting foams, water-repellent clothing and food packaging. Among the most recognized PFAS are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). 

The risk to food supply chains comes from two directions. Firstly, because they are very stable chemical compounds, they persist and accumulate in the environment and ultimately end up in the food chain. Secondly, they can contaminate food during production, packaging and consumption through sealants and lubricants, drinking straws, disposable cups and paper packaging.  

PFAS are linked to numerous health issues, including thyroid disease, high cholesterol, liver damage, kidney and testicular cancer, reduced vaccine response and lower birth weight. They are categorized as either short- or long-chain compounds, which can influence their toxicity. For example, short-chain compound perfluorobutanoic acid (PFBA) has a half-life of two to four days, while longer-chain compound PFOS has a half-life of 5.4 years. Generally, as chain length increases, so does toxicity.  

The legal framework 

The European Food Safety Authority (EFSA) has established a tolerable weekly intake of 4.4ng per kg of body weight for four PFAS compounds: PFOS, PFOA, perfluorononanoic acid (PFNA) and perfluorohexane sulfonic acid (PFHxS). Consequently, the EU has set limit values for these compounds in animal-origin foods and guideline values for some plant-based foods since 2023. The European Drinking Water Directive now includes limits for 20 PFAS compounds and a total limit of 500 ng/L for all PFAS, currently under critical discussion. Since 2024, the US’ National Primary Drinking Water Regulation has included strict limits for PFOA, PFOS, PFHxS, PFNA and hexafluoropropylene oxide dimer acid (HFPO-DA). Both the EU and the US have also introduced measures to restrict or ban PFAS in products. While global restrictions vary and sometimes apply only to specific compounds, regulations are tightening worldwide.  

The complexity of PFAS 

The PFAS issue is complicated by the number of different compounds involved. The OECD Global Database lists 4,729 compounds, but according to the 2021 OECD definition, substances such as trifluoroacetic acid are also considered PFAS. It is therefore estimated there are between 5,000 and 10,000 compounds, many lacking analytical standards. The EU focuses primarily on C4-C13 perfluorocarboxylic and sulfonic acids, while the American EPA Method 537.1 for drinking water includes compounds such as HFPO-DA, 11Cl-PF3OUdS, 9Cl-PF3ONS and ADONA. The toxicology and bioaccumulation properties of these compounds vary significantly. For example, 9Cl-PF3ONS, a major component of F-53B, is the most biopersistent PFAS with a half-life of 15.3 years and is primarily detected in China. The most frequent compounds found in food contact-material studies are fluorotelomer alcohols (FTOH) and sulfonates (FTS). 

A holistic approach to risk assessment 

Avoiding PFAS is a major challenge for food manufacturers, who have limited control over many influencing factors. However, they can conduct risk assessments for their products based on current research. 

Location risk 

Location – the geographical area where plants are grown and animals raised – is a major risk factor. High-quality maps are now available for Europe, the US and China, showing PFAS contamination in groundwater and soil, aiding risk assessment. For example, elevated levels have been found in drinking water in Brunswick County (185.9 ng/L), Quad Cities (109.8 ng/L) and Miami (56.7 ng/L) in the US. Similarly, certain regions of China, such as Zigong (502.9 ng/L), Lianyungang (332.6 ng/L) and Changshu 122.4 ng/L), exhibit high PFAS concentrations, especially near airports and chemical, paper and textile factories.  

Food type 

Food type significantly influences PFAS levels. Animal-based foods generally contain higher PFAS concentrations than plant-based foods. Depending on the species, fish can also have high levels. The US Food and Drug Administration has detected high levels in clams, up to 23 µg/kg, followed by crabs, tuna and cod, with lower levels in salmon and tilapia. Game meat and liver can also show extreme PFAS levels, sometimes up to 2,000 µg/kg. Long-chain C8-C12 PFAS dominate in these products. Milk and dairy products tend to show lower levels, although isolated cases show levels measuring up to 1.5 µg/kg. One study found organic and free-range eggs may have higher concentrations, probably due to free-range farming practices. Other studies have identified animal feed as the primary source of PFAS contamination in eggs.  

Plant-based foods usually have lower levels of PFAS, although EU guidelines are significantly lower. Studies indicate short-chain PFAS like PFBA tend to accumulate in fruit, whereas long-chain PFAS are more common in roots. Mushrooms often have higher levels than fruit and vegetables. An Italian study detected PFBA in some rice samples with a maximum level of 0.03 µg/kg, a relatively lower level.  PFAS are absorbed from the soil via the roots and distributed throughout the plant. Other potential sources include contaminated irrigation water and PFAS-containing pesticides.  

Processing 

Production water, which may contain high levels of PFAS, is also a significant risk and is used as an ingredient in food or for cleaning. Another risk is the use of materials containing PFAS in production. In particular, high temperatures and complex manufacturing processes, such as in cooking oil production, may pose a risk of PFAS migrating into food. Paper-based food-contact materials can contain PFAS (eg, FTOH and diPAPs), which can migrate into the product especially when high temperatures are applied. 

Selecting the right approach for PFAS hazard analysis is as complex as the PFAS issue itself. To achieve a comprehensive assessment, testing various matrices – such as soil, drinking water, animal feed, food and packaging – can be invaluable. Each matrix presents unique challenges and opportunities. For example, drinking water and packaging may be assessed using a range of analytical methods to quantify overall PFAS contamination. In food, a low limit of quantification and the correct selection of compounds play an important role.  

With an extensive global network of state-of-the-art testing facilities, SGS is recognized as a leader in PFAS testing across all industrial segments and matrices. Our solutions for the food industry cover all aspects of the value chain, from raw ingredients to packaging materials. With limits of quantification down to 0.1 ng/kg and a selection of around 100 compounds, SGS can support you in your quality assurance. In addition to the classic LC-MS and GC-MS methods, SGS also offers innovative approaches such as TOP-Assay and EOF. 

Despite the need for further research, manufacturers can evaluate and monitor risk through specific questions regarding their products. Comprehensive measures are necessary throughout the entire value chain, as the food industry alone cannot solve the PFAS problem. Enhanced regulations and improved technology for reducing PFAS in wastewater are critical for addressing this pervasive issue.  

For more information visit www.sgs.com/pfas  

About the author  

Nicola Ackermann, Business Development Manager – Beverages, Health & Nutrition, SGS   

Nicola has been with SGS for nine years and is the business development manager responsible for beverage analysis, supporting bottlers and trading companies with quality assurance. He also leads the development of new services and analyses to meet evolving client needs. As a product specialist for PFAS analysis, he publishes studies and customer insights on PFAS in food and beverages, advising clients on the selection of suitable analytical methods to ensure product safety and compliance.