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  1. Process Contaminants in Food

Testing Food for PFAS and Assessing Dietary Exposure

<< Per- and Polyfluoroalkyl Substances (PFAS)

PFAS can enter foods through environmental contamination or through migration from food packaging. PFAS can enter the environment because of pollution from industrial facilities where PFAS are produced or used to manufacture other products, from the use of PFAS-containing products, and from discarded products leaching PFAS in landfills. In addition, 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 very 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.

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.

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 as well as conducted targeted sampling of certain types of food. 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.

FDA Approach to Human Health Assessments

When the FDA detects PFAS in food we conduct 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 PFAS detected in that food, and if there is scientific information on the toxicity of the specific type of PFAS.

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.

There are currently eight PFAS (PFOA, PFOS, PFNA, PFHxS, HFPO-DA ⌈GenX⌉, PFBS, PFBA, and PFHxA) from environmental contamination for which there are toxicological reference values that are used to assess the potential human health concern for levels found in food. Currently, FDA evaluates these PFAS individually in food samples; however, we are exploring approaches for evaluating samples with multiple PFAS detected. Additionally, the FDA does not consider the possible additive effects of PFAS exposure in samples where more than one type of PFAS is detected. As the science continues to evolve on establishing additional TRVs and on cumulative exposure assessments, our conclusions related to the potential human health concerns for certain levels of PFAS found in food may change.

The agency is currently 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, HFPO-DA (GenX) and PFBA, in our evaluations of the exposure to certain PFAS detected in foods.

Testing for PFAS in Total Diet Study Samples

The FDA has been working to better understand if food from the general food supply is a significant source of PFAS exposure for U.S. consumers. The FDA has been testing foods collected as part of the FDA’s Total Diet Study (TDS) since 2019. TDS foods are regionally and nationally distributed, 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 TDS sample sizes for each type of food tested are very limited, therefore, the FDA uses only a complete “market basket” consisting of 24 regional and two national collections to estimate nutrients and contaminants in the general food supply. For PFAS we are approximately a third of the way there. Once we have tested a full market basket, we will be better able to estimate U.S. consumers’ exposure to PFAS from foods. We cannot, therefore, use our data from testing for PFAS in TDS samples to draw definitive conclusions about specific foods.

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 or types of food, and to help inform the agency’s approach to future surveillance efforts. For example, after testing of TDS samples showed that of the very few samples that had detectable levels of PFAS, most were seafood, the FDA conducted a targeted seafood survey in 2022.

Targeted Sampling of Seafood

In 2022, the FDA tested 81 samples of clams, cod, crab, pollock, salmon, shrimp, tilapia, and tuna. The testing results showed a much greater percentage of samples had detectable levels of PFAS, there were more different types of PFAS detected, and the levels detected in multiple samples were higher than we have seen in our previous testing of foods from the TDS.

In addition, the FDA determined that the estimated exposure to perfluorooctanoic acid (PFOA), a type of PFAS, from the samples of canned clams, which were from China, is likely a health concern. Except for canned clams from China, we have determined that none of the other PFAS exposures with TRVs at the levels measured in FDA’s testing of seafood are a likely to be a human health concern. For canned clams, voluntary recalls were issued by two firms, and we are continuing to test a limited number of import shipments at the border and domestic products on the market.

Filter feeders, such as clams, but also other bivalve mollusks, including oysters, mussels, and scallops, have the potential to bioaccumulate more environmental contaminants than other seafood types. We are therefore pursuing additional sampling in 2023-2024 of imported and domestic bivalve mollusks to better understand PFAS in commercially available seafood.

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 technical 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.

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