Testing Food for PFAS and Assessing Dietary Exposure
<< Per- and Polyfluoroalkyl Substances (PFAS)
PFAS can enter the food chain through environmental contamination or through migration from food packaging. Typically, environmental contamination is limited to a specific geographic area, for example, near an industrial facility where PFAS are produced or used to manufacture other products, or an oil refinery, airfield or other location where PFAS-containing products are used for firefighting. PFAS can also enter the environment through discarded products in landfills. The use of soil, water, or biosolids contaminated with PFAS to grow crops, feed animals intended for food, or raise fish or other seafood, can lead to PFAS entering the food supply. The specific types of PFAS that can migrate to food from food packaging go through FDA review before they enter the market to ensure that exposure levels from their intended use do not pose a health risk.
For more information, please visit Authorized Uses of PFAS in Food Contact Applications.
Method for Testing PFAS in Food
FDA scientists are at the forefront of developing new and more sensitive testing methods to measure low levels of PFAS concentrations in food. Since 2012, the FDA has been refining the analytical method to test food for PFAS by testing specific groups of food, as well as focusing testing efforts on foods grown or produced in areas associated with environmental PFAS contamination.
In 2019, the FDA expanded the methods used in earlier testing and made available the first single-lab validated scientific method for testing 16 different types of PFAS in a highly diverse sample of foods. In 2021, the FDA optimized this method for use in processed foods. In 2022, the FDA announced that four additional PFAS (PFUda, PFDoA, PFTrDA, and PFTeDA) were added to the analytical method and were included in the analysis of the fourth TDS regional collection and in a 2022 survey of seafood. This method is being used to continue testing foods from the general food supply and in our work supporting states in assessing the safety of human and animal food from specific areas potentially affected by environmental contamination.
For the scientific method, please visit: Determination of 16 Per and Polyfluoroalkyl Substances (PFAS) in Food using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) (Version 2021). Update: The extended method with four additional PFAS will be posted in Spring/Summer 2022.
Assessing Dietary Exposure to PFAS
To understand the potential dietary exposure to PFAS from food, the FDA has focused its testing on foods most commonly eaten by people in the United States. The FDA also conducts testing of food grown or produced in areas with known environmental contamination, to detect and evaluate potential contamination of human and animal food. When the FDA finds a detectable level of PFAS, the agency conducts an assessment to evaluate whether the level detected presents a possible human health concern and warrants further FDA action.
The types of PFAS the FDA tests for depends on the availability of chemical standards and is also informed by the scientific literature. For example, in the FDA’s 2022 survey of seafood some of the PFAS that were added to our method had been identified in the literature as being more prevalent in seafood.
General Food Supply
The FDA has been working to better understand if food in the general food supply is a significant source of exposure to PFAS for U.S. consumers. Beginning in 2019, the FDA has been testing foods originally collected as part of the FDA’s Total Diet Study (TDS). TDS foods are purchased at grocery stores and represent the broad range of foods—breads, dairy, produce, meat, fish, poultry, as well as processed foods, such as macaroni and cheese and salad dressing, etc.—the average U.S. consumer might eat.
The sample sizes for the specific types of foods are limited and therefore cannot be used to draw definitive conclusions. The purpose of testing the TDS samples for PFAS is to better understand the occurrence of PFAS in foods, determine if targeted sampling assignments are necessary for certain foods, and to help inform the agency’s approach to future surveillance efforts.
The results from the analysis of foods from the general food supply will, along with other testing results, help to inform the FDA’s risk-based approach to identifying, prioritizing, and implementing the agency’s activities to reduce exposure to PFAS from human and animal food.
Food Grown or Produced in Specific Geographic Areas Contaminated with PFAS
The FDA also tests foods grown or produced in areas with known PFAS contamination. This support generally occurs at the request of states and before the food enters the market. As needed, the FDA conducts evaluations to determine the potential dietary exposure to PFAS from these foods. Previous analyses by the FDA have shown that PFAS contamination in the environment where food is grown does not necessarily mean the food itself will contain detectable PFAS. This is because the amount of PFAS taken up by crops depends on many factors, including the specific type of PFAS and characteristics of the food.
When levels of PFAS in foods are determined to be a human health concern, the FDA works closely with state and local officials, as well as our federal partners, to assess each situation and take appropriate steps to ensure the food does not enter the market.
FDA Approach to Human Health Assessments
When there are detectable levels of PFAS in foods, the FDA conducts an assessment to evaluate whether the levels detected present a possible human health concern. The FDA’s approach considers a number of factors, including whether there is an established action level or tolerance, how much of the specific food people typically eat, the level of the contaminant detected in that food, and the toxicity of the specific contaminant(s).
As part of the FDA’s ongoing effort to use the best available current science to assess the exposure to PFAS from foods, the agency monitors the scientific literature and available toxicological reference values (TRVs) for PFAS and updates the values based on merits and applicability of the underlying studies. Recently, the agency began using the finalized minimal risk levels (MRLs) from the Agency for Toxic Substances and Disease Registry’s May 2021 Toxicological Profile for Perfluoroalkyls, along with EPA reference doses for PFBS and HFPO-DA (GenX) also finalized in 2021, in our evaluations of the exposure to certain PFAS detected in foods.
The development of toxicological reference values is an area of ongoing scientific research. There are six PFAS (PFOA, PFOS, PFNA, PFHxS, HFPO-DA ⌈GenX⌉, and PFBS) from environmental contamination for which the FDA can assess the potential human health concern for levels found in food. At this time, there are no other appropriate toxicological reference values for the other types of PFAS that the FDA may test for. Therefore, it is not possible to determine at what levels exposure may be a potential health concern. Additionally, we are not able at this time to determine if there is a cumulative health risk from co-exposure to multiple types of PFAS detected in a certain sample.