Red Dye No. 3 and the Delaney Clause:
A Relic of the Past or a Necessary Safety Measure?
It’s time to stock up on maraschino cherries—Red Dye No. 3 is officially off the market (sorry, Peter Barton Hutt, cherry enthusiast and leading food and drug lawyer). On Jan. 15, 2025, the U.S. Food and Drug Administration (FDA) banned the use of Red Dye No. 3 in food, drinks, and drugs.
It’s time to stock up on maraschino cherries—Red Dye No. 3 is officially off the market (sorry, Peter Barton Hutt, cherry enthusiast and leading food and drug lawyer).
On Jan. 15, 2025, the U.S. Food and Drug Administration (FDA) banned the use of Red Dye No. 3 in food, drinks, and drugs. Although the agency maintains that the use of the dye is safe and appropriate, the ban is a result of a 2022 petition from consumer advocacy organizations citing an old, contentious law and two studies that show that the dye causes cancer in laboratory male rats. This tension exists within the current regulatory structure: Consumers fear their food supply is poisoning them, while regulators feel limited in their ability to use modern toxicological standards to evaluate actual safety. After decades of consumer mistrust and agency hand-tying, Congress must update the law to allow scientific principles to lead the way in ensuring food safety.
The Regulatory Framework for Food and Color Additives
FDA regulates the U.S. food supply under the Federal Food, Drug, and Cosmetic Act of 1938 (FDCA). One of the most significant amendments to the FDCA was the addition of the 1958 Food Additives Amendment (FAA) and subsequently the 1960 Color Additives Amendment (CAA) (Chapter VII, section 721). Before a color additive can be marketed to consumers, the agency must determine that it is safe “with reasonable certainty of no harm.” This “general safety clause” in the FDCA requires FDA to consider various factors including the probable consumption levels, cumulative effect of consumption, animal experiment data, and its physical and chemical properties.
Before voting on the FAA in the House of Representatives, Congressman Delaney (whose wife was battling cancer at the time) insisted that that the bill include language—now known as the Delaney Clause—which requires that a food additive will not be approved by the FDA “if it is found to induce cancer when ingested by man or animal.” The Delaney Clause was included in the CAA when it was passed a few years later. While a seemingly innocuous phrase, this language has come to haunt FDA. Initially, the agency struggled to understand how the Delaney Clause limited its discretion in approving additives if a substance did not induce cancer at relevant doses or intended uses. However, the leading 1987 D.C. Circuit case understood Congress to intend an “extraordinarily rigid” interpretation of the Delaney Clause to protect the public from cancer-causing ingredients. This remains FDA’s interpretation today, limiting the agency’s ability to approve a food additive if at any dose—not just relevant doses—it is known to cause cancer in humans or animals. Together, the FAA, CAA, and Delaney Clause give FDA the authority to review the safety of food additives before they can legally enter the market but also greatly limits the agency’s discretion in this analysis.
The History and Future of Controversy under the Delaney Clause
FD&C Red No. 3 (“Red No. 3”) is a synthetic dye that is added to foods to give them a desirable bright, cherry-red color. It is often found in candy, frostings, and ingested drugs. Under the general safety standard, Red No. 3 was approved to be added to food in the U.S. market and was “provisionally listed” to be approved in cosmetics and externally applied drugs.
Yet controversy over the additive began shortly after approval. In the early 1980s, the National Toxicology program began studying Red No. 3 in lab animals. As a result of early evidence showing ”convincing evidence of carcinogenicity in male rats,” in 1990, FDA eliminated the provisionally listed use of the additive, banning its use in topical products. For more than 35 years, consumer advocacy groups have continued to study the effects of ingested Red No. 3 in lab animals. As a result, on Oct. 7, 2023, California banned the use of Red No. 3 in any food product manufactured or sold in the state.
The current controversy over Red No. 3 highlights the importance of the Delaney Clause. Proponents of the clause argue that regulatory bodies should be unforgiving when it comes to ingredients in our food and cosmetic supplies that could induce or cause cancer at any level. Consumer advocacy groups continue to advance this argument, publicizing various clinical trials in lab animals and organizing mass grassroots campaigns to inform the public that—under specific circumstances—Red No. 3 has been shown to induce cancer in animals.
On the other hand, FDA and stakeholders argue that the strict literal interpretation of the Delaney Clause inhibits scientific advancement and unnecessarily undermines trust in the institutional regulatory system. Even in the latest press release, FDA insists that the ban on Red No. 3 is merely required by the Delaney Clause in response to the petition—as a matter of law—not because of safety concerns, noting the biological mechanism through which rats develop cancer as a result of exposure does not occur in humans. While lab animal studies may be a reasonable basis for taking precautions in some circumstances, the Delaney Clause undermines FDA’s ability to determine for itself whether the data presents a “reasonable certainty of harm.”
This tension begs us to ask whether the Delaney Clause is an appropriate way to determine safety of the U.S. food market. It was introduced in 1958 when little was known about the etiology of cancer and toxicology. Despite the famous 16th century phrase from Paracelsus (the great-grandfather of modern toxicology) that “the right dose differentiates a poison and a remedy,” the Delaney Clause implies that exposure to a chemical with carcinogenic effects at some level presents a serious risk of cancer at every level. It is now well understood that the development of cancer is complex and multifactorial. Limiting FDA to rigid, unscientific language may instead be doing more harm than good.
About the author
Jessica Samuels is a third-year dual degree law and public health student (J.D./MPH 2025). Her research interests include genetics, environmental health sciences, novel biotechnologies, and the FDA regulatory process. She has previously published work on the accuracy of ultrasound in predicting malignant ovarian masses. At HLS, Jessica is co-president of the Harvard Health Law Society.
