FDA’s Proposed Post-Market Assessment of Food Additives and Chemicals in Food

If FDA plans to elevate its post-market chemical review to a new level, it should introduce a robust regulatory scheme that is adopted through a regular rulemaking procedure.

The U.S. Food and Drug Administration (FDA) is making progress on its planned endeavor to take a closer look at substances added to or otherwise found in food and food contact materials. On June 18, 2025, FDA released its proposed "method of prioritizing chemicals [in the food supply] identified for post-market assessment," which is intended to create a "science-based, data-driven, systematic, and reproducible process" to prioritize its post-market review of chemicals in food. [1] Public comments on the tool were accepted through mid-August. Those comments are now being provided, along with the prioritization method, to external scientific experts for further evaluation.

The publication of the prioritization tool follows from an FDA Discussion Paper, [2] published in August 2024, that outlines FDA's "enhanced systematic approach for the post-market assessment of chemicals in food." Eligible for inclusion in the assessment are additives intended for direct addition to food; substances, additives, and articles used in contact with food; color additives; generally recognized as safe (GRAS) substances; and chemicals present in food as unintentional contaminants.

Under the approach described in the discussion paper, [2] FDA would identify new information on various chemicals through monitoring of new submissions to FDA, scientific publications, international and U.S. regulatory activities, adverse event reports, news reports and trade press, and social media. Then, FDA would conduct a preliminary evaluation of the information to determine if a post-market assessment is needed. If such an assessment is found necessary, then a decision would be made as to whether to conduct a "focused" or "comprehensive" assessment; the former being a shortened review based on the available data and potential hazards and exposure. Risk management actions would follow a completed assessment, as needed. Presumably, FDA is still determining the details on how these aspects of the program will be worked out or scrapped.

Following a two-year pilot program, FDA's announcement of the development of its Post-Market Assessment Prioritization Tool is a significant step forward in making this enhanced system of post-market review a reality. The prioritization tool is designed to score chemicals on various considerations that will then be used to rank the priority each of the chemicals should be given for evaluation and assessment. The method designed by FDA employs a Multi-Criteria Decision Analysis (MCDA), which includes four "Public Health Criteria" and three "Other Decisional Criteria." These latter criteria have to do with the attention a chemical is receiving by Congress, the media, non-governmental agencies (NGOs), and other government agencies, as well as potential impacts on public confidence. The higher the total score for a substance calculated using the MCDA, the higher it will be ranked for post-market review.

The four Public Health Criteria are:

1. The potential of the chemical to cause severe health effects (e.g., cancer, cardiovascular toxicity)
2. Increased dietary exposure to the chemical over time
3. Detection of the chemical in food intended for vulnerable subpopulations (e.g., infants), or the potential for it to be present
4. New scientific information could have a significant impact on the conclusions of previous assessments of the chemical.

Other Decisional Criteria include:

• The chemical has received high attention from Congress or through national media coverage, multiple organizations are monitoring it, and/or stakeholder groups are active in setting standards for it
• Multiple government agencies are making decisions or taking action on the chemical
• Failure to assess the chemical would cause the public to lose confidence in the safety of the U.S. food supply.

FDA has proposed that the total score of the Public Health Criteria and the Other Decisional Criteria are to be given equal weight in scoring, with a total score of one through nine to be assigned to both categories. 

FDA emphasized in the proposal that a substance's score and its overall ranking based on the Post-Market Assessment Prioritization Tool is not a determination as to whether the substance poses a public health risk. Rather, the prioritization tool "will be used to support Agency resource allocation" for its modernized review process for chemicals already in the food supply. FDA has indicated that it intends to publish the full process for this review later this year.

Scientific vs. Non-Scientific Criteria

FDA received 89 comments on the proposed Post-Market Assessment Prioritization Tool. [3] Significant concern was raised by many of the commenters on the other decisional criteria and the weight that it is proposed to be given. For example, the Food Packaging Coalition stated in its comments, "FDA should apply a non-numerical value to 'Other Decisional Criteria,' as these criteria are not science-based and fall outside the risk-based framework prescribed for FDA by Congress." The group added, "Using qualitative influences such as media attention and public confidence as quantitative factors distorts the underlying scientific basis of the ranking." It recommended creating "a separate qualitative ranking pathway to categorize subjective criteria that does not conflate the quantitative with the qualitative."

Numerous other organizations, including industry trade associations and NGOs, agreed that non-scientific criteria should not be given the same weight as scientific criteria. Excerpts from some of the other comments expressing concern with FDA's proposal are shown below.

Consumer Brands Association (CBA):

As a science-based and public health Agency, FDA should give more weight to the Public Health criteria—toxicology, exposure, risk to susceptible populations, and new scientific information relevant to human exposures, than a set of criteria that takes into consideration the level of media attention a substance is receiving regardless of source.

Environmental Defense Fund (EDF):

Two components of the Other Decisional Criteria, the "external stakeholder activity/attention" and "building public confidence" components, should not be included as prioritization criteria. These factors cannot be quantified even if FDA assigns numerical scores to them, and they will lead to biased and highly variable results that will undermine the intent of a scientific tool.

Calorie Control Council (CCC):

CCC does not agree with the inclusion of public confidence criterion since it is not scientific and is based in part on misinformation campaigns that drive public concern. If public confidence is a criteri[on], it should be given less weight… Scoring of public confidence automatically brings in subjective and political considerations into an objective scoring system[,] which defeats the intended purpose.

Institute of Food Technologists (IFT):

Building public confidence in the FDA and our food system at large is critical and would be an outcome of a science-based, data-driven, systematic, and reproducible process for prioritization and resulting post-market assessment of food chemicals, specifically additives and contaminants. Instead of integrating qualitative measures in the prioritization tool, a separate process considering the sentiment, and other concerns, could be evaluated after the scientific components are completed.

Kentucky Department of Agriculture:

While I commend the FDA's intent to improve food safety and consumer protection, I am deeply concerned that the tool's current framework is susceptible to politicization and pressure from ideologically driven campaigns—especially those aimed at modern agricultural practices. The tool purports to rely on scientific evidence and public health risk to prioritize which food chemicals merit further scrutiny. However, in practice, its weighting of "public concern" and exposure routes opens the door for interest groups to unfairly target essential components of food production such as pesticides, fertilizers, and cropland-derived ingredients. These are vital elements in ensuring food security, sustainability, and affordability for the American public.

With respect to multiple governments making decisions or taking action under "Other Decisional Criteria," CBA referenced FDA's scientific expertise regarding food chemical safety and expressed concern about emerging legislative actions by state governments to restrict, require warnings, or outright ban federally authorized food ingredients. CBA stated, "While the intent of state legislation may be to increase consumer confidence in the safety of the food supply, these jurisdictions lack the scientific expertise that FDA has and are implementing ingredient restrictions without the use of any proper scientific or regulatory process designed to deliver science[-] and risk-based regulatory outcomes."

Some officials at FDA have indicated that this reason is why the Other Decisional Criteria are proposed to be included in the scoring system. It is thought that if FDA acts on substances that are considered a concern by the public or state or federal legislators in an expedient and effective way, it may act as a damper on legislative action being taken on specific substances without a full understanding of the scientific basis upon which such decisions should be made. Said another way, part of the purpose of the program can be viewed as FDA's need to build (some might say, "rebuild") and maintain the confidence of the public in the safety of the food supply.

Public Health Criteria: Toxicology

FDA explained that the toxicity criteria outlined in the proposal would be scored by utilizing a rubric that consists of seven different data types:

1. Acute toxicity
2. Carcinogenicity/mutagenicity/genotoxicity
3. Developmental and reproductive toxicity
4. Neurotoxicity
5. Other organ-specific toxicity
6. Immunotoxicity
7. Bioaccumulation/biopersistence.

Although in some rare instances acute toxicity concerns may be of importance to prevent imminent and significant health or safety consequences with respect to food, problems of this sort become quickly apparent and are acted on with immediacy by FDA and other public health agencies. Any additional attention needed to establish guardrails to prevent future issues with the substance are then taken.

The real rub on toxicity issues will be whether FDA expands its sights to include robust consideration of chemical substances targeted as so-called "endocrine disruptors" and the kind of data that will be needed to establish concerns. On the other hand, it will not be surprising if FDA places greater emphasis on chemical bioaccumulation potential and its effect on the validity of chronic studies, which may not fully account for the rate at which a substance may enter the body compared to the rate at which it is broken down (metabolized) and removed. Bioaccumulation is one of the issues FDA highlighted as a weakness with the chronic studies generated in support of some PFAS products.

Change in Dietary Exposure Criterion

FDA's "change in exposure" criterion is subject to criticism on two scores. First is the absence of it being tied to toxicologically relevant exposure principles, using vague descriptions such as "considerably increased" and "moderate increase," which do not correspond to FDA defined or recognized toxicity thresholds or other risk-based, scientific standards.

More importantly, though, is FDA's seeming focus on measuring a "change in exposure" by way of an increase in production volume of the chemical rather than by the prevalence of a food chemical in the consumer's diet. Production volume increase, in and of itself, does not necessarily equate to an increase in dietary intake for consumers. Such increases could result from higher demand for a chemical in nonfood applications or could simply be reflective of a growing population. Given FDA's long adherence to the adage that "the dose makes the poison," the Agency focus should remain on estimated dietary intake as it relates to corresponding toxicity risk (no pun intended).

It will also be important to watch how FDA handles its third criterion on chemicals that have been found or may potentially be present in food intended for vulnerable subpopulations—not so much for how the chemical substance is handled, but how new subpopulation groups are chosen and defined. FDA review staff have for several years now considered infants to be a vulnerable subpopulation. This is understandable given the different metabolism and growth rate of infants, the amount of food consumed relative to body weight, and an infant's dependence on consumption of a specific food type/brand over the period of infancy.

Whether FDA decides to include special intake considerations for other subpopulation groups and the justifications that would be needed to support such a determination is something the food industry and ingredient producers will need to watch. Tied to this notion is whether FDA may consider demographics and information on the habits of specific age groups with respect to food consumption, as well as known nutritional deficiencies, or whether FDA decides that its current exposure model employs sufficient conservatisms to account for such subpopulation groups.

Finally, other public health issues the Agency will need to grapple with include how "weight of evidence" issues will be handled at the very early prioritization stage and the safeguards, if any, the Agency will establish on the use of artificial intelligence (AI) in gathering and digesting studies on various chemicals.

FDA will also likely need to address the risk/benefit analysis that is inherent to many substances used in or with human foods, considering its responsibility in assuring not only a safe but also a nutritional food supply. This latter means having sufficient quantities of a variety of food products available to the U.S. population (which is quickly approaching 350 million people) to satisfy nutritional needs. Such items as preservatives, stabilizers, and packaging play a significant role in this aspect of FDA's mission.

Number of Chemicals to be Prioritized

FDA will need to walk a fine line on the number of chemical substances it brings into the prioritization process against the timeline that is established for completing reviews of these candidates. Assuming that the entire process is open to public scrutiny, FDA will need to be transparent as to the bases of its decisions for a chemical substance's inclusion in the prioritization evaluation scheme, as well as the basis for its decision on whether to advance the chemical substance to the full assessment stage.

It will also be important that FDA have a well-defined timetable for the review of these chemicals and that it sticks with that timetable. For this effort to work, the Agency must ensure that it does not bite off more than it can chew. 

Given the potential for deselection to occur on the announcement of a substance simply being considered for prioritization, industry will protest mightily if a substance of widespread use is selected and then faces a lengthy review process—or worse, is "deselected" from use before the process is completed. Consumers may also be unsettled by such scenarios. As the Council for Responsible Nutrition stated, "Publishing a lengthy list of chemicals without defined, realistic timelines for completion would undermine public trust."

At present, FDA has listed on its website 32 substances under review, including cleared food ingredients, food contact substances, and contaminants in food. Of these, five reviews have been completed. The Agency has not published a timeline for completing the remaining reviews. How many additional substances should be included in the program? That depends on the resources available to FDA and the priority that is placed on the program relative to the Agency's other responsibilities. Diminished funding and staff reductions are not going to help the process.

Need for Regulations

In 2024, FDA held public meetings and published a discussion paper on the full post-market review process. More recently, in June 2025, FDA published the aforementioned "Post-Market Assessment Prioritization Tool." Strikingly, the only public announcement of this process that has been published in the Federal Register is the public meeting that was held in autumn 2024.

At present, FDA's post-market review of chemical substances in the food supply is informal. It functions mainly to fulfill FDA's legal obligation to keep an eye on compliance with federal law and regulations concerning food additives, ingredients, and potential contaminants. If FDA plans to elevate these activities to a new level, it should introduce a robust regulatory scheme that is adopted through a regular notice and comment rulemaking procedure. FDA must fully describe the following:

• Why it sees a need for the program
• Its objectives in establishing it
• The methods by which chemical substances will be selected for review
• The criteria and method by which the selected candidates may advance through the risk assessment process and, if deemed necessary, the risk management stages
• The rights of chemical manufacturers and users to observe and participate in the process
• The rights of others to observe and participate
• The rights of the participants to object to the outcome of the process and request an administrative hearing and adjudication of the matter.

The stakes of having a federal agency declare a substance as unsafe, restricted, or prohibited from its previously authorized use in food are high. Therefore, a procedure is needed that is fully vetted by way of public notice through the Federal Register and with regulations that are published in the Code of Federal Regulations. 

It could be that FDA intends to take this step at some point once it completes its collection of preliminary thoughts and data; or it could be that the Agency has no intention of elevating these post-market review activities to a formal, vetted program. FDA cannot and should not conduct its post-market chemical review process under the guise of a well-organized and well-funded program while trying to keep it as an informal activity. Doing so ensures that no one's rights are protected.

This article is reprinted with the permission of Food Safety magazine. It first appeared in the December 2025/January 2026 issue. 

[1] U.S. Food and Drug Administration (FDA). "FDA Seeks Input on a New Method for Ranking Chemicals in Food for Post-Market Assessments." Current as of June 18, 2025. https://www.fda.gov/food/hfp-constituent-updates/fda-seeks-input-new-method-ranking-chemicals-food-post-market-assessments.

[2] FDA. "Discussion Paper: Development of an Enhanced Systematic Process for the FDA’s Post-Market Assessment of Chemicals in Food." August 2024. https://www.fda.gov/media/180942/download.

[3] Regulations.gov and FDA. "Tool for the Prioritization of Food Chemicals for Post-Market Assessment." Docket No. FDA-2025-N-1733. https://www.regulations.gov/docket/FDA-2025-N-1733.