Scientific Questions Arise with Regulatory Actions Towards Synthetic Food Dyes
In January 2025, the Food and Drug Administration (FDA) banned FD&C Red Dye No. 3 (erythrosine) in food and ingested drugs, citing animal studies that linked it to cancer. This marked one of several recent regulatory actions that highlight the ongoing scientific debate surrounding prominent synthetic dyes using food coloring and other purposes. The FDA’s action on Red Dye No. 3 was based on the Delaney Clause of the Federal Food, Drug, and Cosmetic Act, a provision passed in 1958 that prohibits the approval of any food additive found to induce cancer in animals or humans. Among oft-cited criticisms of the Delaney Clause is the failure to consider dose, or the amount of the chemical substance at issue needed to induce cancer in an animal or human and whether cancer observed in an animal also is expected to occur in humans. While animal studies demonstrate that Red Dye No. 3 can lead to thyroid cancer in rats, the FDA acknowledged significant limitations in terms of human relevance. Namely that humans are not likely to be exposed to Red Dye No. 3 at levels causing cancer in these studies and that the underlying biological mechanisms leading to thyroid cancer in rats are not expected to occur in humans. Thus, while the FDA’s ban of Red Dye No. 3 meets the requirements set forth in the Delaney Clause, it lacks the underlying scientific support that this decision will protect human health. Manufacturers have been given until January 15, 2027 to reformulate food products, although recent statements from the agency suggest the timeline may be accelerated.
Building on this trend, in April 2025, the Department of Health and Human Services (HHS) and the FDA announced plans to phase out other petroleum-based synthetic food dyes by the end of 2026. This included FD&C Green No. 3, FD&C Red No. 40, FD&C Yellow No. 5, FD&C Yellow No. 6, FD&C Blue No. 1, and FD&C Blue No. 2. The FDA also intends to revoke authorization for Citrus Red No. 2 and Orange B. This phase-out is currently framed as a voluntary request to the food industry.
An Emerging Patchwork of Bans and Restrictions
In addition to actions at the federal level, several states are taking legislative action to limit or ban artificial food dyes. California’s Food Safety Act (AB 418) bans Red Dye No. 3 and other additives statewide starting in 2027. The California School Food Safety Act (AB 2316) further bans six synthetic food dyes from public schools by the end of 2027. West Virginia House Bill 2354 enacted a broad ban on seven synthetic food dyes and two preservatives, effective in schools by August 2025 and statewide by January 2028. Virginia (S 1289 and H 1910) and Utah (HB 402) have also passed laws banning several artificial dyes from school food programs. Arizona HB 2164 restricts “ultraprocessed” foods, often containing artificial dyes, in federally funded schools. At least 30 states have considered similar legislation, indicating a growing nationwide pressure to eliminate the use artificial dyes from food products (Association of State and Territorial Health Officials, 2025).
Neurobehavioral Effects as an Emergent Issue
One area of ongoing research and potential driver of regulations is an alleged link between artificial food dyes and neurobehavioral effects, particularly in children. These effects can include hyperactivity, inattention, and irritability. Scientific analyses and reports from the California Office of Environmental Health Hazard Assessment (OEHHA) identified an association between synthetic food dye consumption and adverse behavioral effects in children. However, other meta-analyses and reviews have questioned or contradicted these conclusions. In particular, limitations in the studies which OEHHA relied upon were highlighted for the use of small study populations and varying quality. In addition, only a slight majority of studies (52%) found a significant effect on neurobehavioral outcomes indicating inconsistent evidence and the lack of information to explain the biological pathways contributing to adverse effects. Together, the scientific literature demonstrates an unresolved issue that warrants further investigation to definitively link synthetic food dyes with neurobehavioral issues in children.
Future Regulatory and Litigation Pressures
Despite the ongoing scientific questions and uncertainty, findings from OEHHA or other groups may spur continued regulations or even litigation impacting manufacturers and suppliers of foods containing certain dyes. This situation mirrors previous cases involving other food additives where manufacturers faced legal challenges over alleged health risks and misleading marketing.
Navigating the Issue
For over 25 years, CTEH has been providing toxicological consulting, product safety analysis, and feasibility support services. With experience in addressing complex scientific issues, our CTEH team can provide a clarity assisting with issues related to product safety, health claims, and compliance. Contact CTEH today or learn more about our experts by clicking below
About the Authors
Eric Ditzel, PhD, DABT
Project Toxicologist
Dr. Eric Ditzel is a board-certified toxicologist with 10 years of experience in toxicology, regulatory affairs, and product safety. His background spans a range of industries, with deep expertise in consumer products, antimicrobials, food-contact materials, industrial cleaning, and abrasives. Dr. Ditzel provides scientific and strategic leadership in toxicological risk assessment, regulatory compliance, and product stewardship....
Read More About the Author
Derek Drechsel, PhD, DABT, CIH
Senior Toxicologist
Dr. Derek A. Drechsel is a Senior Toxicologist with consulting experience in applied toxicology, product safety, exposure assessment, and human health risk assessment. He has provided technical expertise for numerous projects involving exposure to chemicals in a variety of occupational, environmental, and consumer settings. Dr. Drechsel has performed toxicological evaluations and quantitative exposure analyses to...
Read More About the Author
