Op-ed: An open letter to the Food and Drug Administration Commissioner

The U.S. Food and Drug Administration (FDA) is going through a major reorganization to improve efficiency and protect public health.


A recent hearing in front of the House Committee on Oversight and Accountability concluded that the agency stumbles from crisis to crisis, including drug shortages, tainted food and illicit tobacco scandals in recent years.

Although crises such as the contamination of baby food with heavy metals like lead and mercury gain public attention, the scientific approach used by FDA to regulate chemical additives in food is much more opaque.

While it largely flies under the public radar, the agency’s neglect to update its testing to reflect modern science and modern food chemical hazards is a decades-long crisis that impacts all of our health. The agency has fallen behind other nations’ testing and regulations and is not even following laws put in place nearly 70 years ago to keep us safe.

We are calling on FDA Commissioner, Dr. Robert M Califf, to use the agency reorganization as an opportunity to overhaul its approach to chemicals in our food and put public health at the center of its work.

How does the FDA evaluate the safety of food additives and contaminants?

Recently, the FDA published a consumer update entitled, “Is food safe if it has chemicals?” In it, the agency says that it’s the amount of a chemical in food that determines its risk to our health. They use sodium as an example.

While it largely flies under the public radar, the agency’s neglect to update its testing to reflect modern science and modern food chemical hazards is a decades-long crisis that impacts all of our health.

We need sodium to live, but too much sodium can be bad, so they publish guidance on the safe level of sodium to be consumed each day.

But many of the chemicals that wind up in our food are not required for us to live, such as bisphenols like BPA, phthalates or the group of chemicals known as PFAS or “forever chemicals”. In fact, many of these are not required for food production, but leach into food from packaging and equipment.

FDA noncompliance 

The FDA discusses how they intentionally determine an “acceptable daily intake” for a chemical that includes a safety margin. The idea is that this safety margin is so conservative that it will always protect public health.

However, we know chemicals in the diet can come from a variety of food sources and that different chemicals can have the same adverse effect. This is so well-known that the 1958 amendment to the Food, Drugs and Cosmetic Act of 1938 required that FDA evaluate the “cumulative effect of the substance in the diet, taking into account any chemically or pharmacologically related substance or substances in such diet.”

Sixty-six years later and the FDA has never complied with this part of the law. A good example: its guidance for lead in baby food, in which they set the suggested (not required) limit to be 20 parts per billion.

However, there is no safe blood level of lead, which hurts children’s brains, resulting in lower IQ and behavioral problems among other harmful effects.

It’s not just lead: recently, the Dutch risk assessment agency reported that the combined exposure to lead, methyl-mercury, arsenic, polychlorinated biphenyls or PCBs, polybrominated diphenyl ethers or PBDEs and fluoride were much more potent at reducing children’s IQ than any one of these chemicals alone.

Similarly, the FDA continues to defend its ruling that current levels of BPA in food are safe despite the decision by the European Food Safety Authority, the EFSA, to reduce the “safe level” of BPA by 20,000 fold. The FDA defends its position by focusing on BPA as if it is the only chemical in foods that act like the female hormone estrogen. In contrast, it is well known that plastic food packaging contains a number of estrogen-like chemicals, like other bisphenols and phthalates, that can leach into foods.

The failure of the FDA to comply with the 1958 amendment to food safety law is not just a violation of the law but presents a significant risk to American consumers. A citizen’s petition was filed with the agency in 2020 to attempt to cajole it into compliance. The FDA has never responded.

Considering this, we wrote to Commissioner Califf to address this serious shortcoming of FDA’s Human Food Program. The Commissioner has not responded. The letter is re-printed below.

March 11, 2024
Robert M Califf, M.D., Commissioner
United States Food and Drug Administration
Cc: James Jones, Ph.D., Deputy Commissioner
FDA Human Foods Program

Dear Commissioner Califf,

We read with great interest your OpEd with Dr. Warraigh entitled, “Four steps toward meeting the challenge of chronic disease” (The Hill, 02/15/24). This is a particularly important issue considering that the United States is below average compared to peer economies in 9 health domains, including adverse birth outcomes, obesity and diabetes, heart disease and chronic lung disease. And this, as you point out, is despite US taxpayers spending nearly 18% of our GDP on healthcare.

However, we are concerned that there was no mention of food-borne chemicals that are either added to food intentionally or that migrate into food from packaging or processing. The recent analysis by the New York Times of the failure of the food safety system that resulted in hundreds of children being poisoned by lead in applesauce illustrates in part how our system of food safety needs to be improved.

More important to the issue of chronic disease is that of chemicals in the food supply that are being evaluated for safety in a one-by-one approach, rather than considering the “cumulative effect of the substance in the diet, taking into account any chemically or pharmacologically related substance or substances in such diet” as required by the 1958 amendment to the Food, Drugs, and Cosmetic Act of 1938.

Recent studies demonstrate that the cumulative effect of Americans’ exposure to endocrine-disrupting chemicals in the food supply contributes to harmful health impacts including chronic disease, increasing healthcare costs in the hundreds of billions of dollars annually, as well as affecting quality of life.

Importantly, the scientific evidence is sufficient to conclude that the cumulative effects of biologically related substances in the food supply contributes to chronic diseases such as obesity or diabetes. We urge you to consider it as a critical “fifth step” in meeting the challenge of chronic disease in the United States, one that the agency is already mandated to conduct.

For example, a recent study contributed by the Dutch risk assessment agency (RIVM) in collaboration with Professor Andreas Kortenkamp, a world-leader in the analysis of cumulative risk, demonstrated that in 9 countries in the EU, their populations exceeded combined tolerable levels of exposure to a mixture of chemicals at median exposure levels. Thus, the traditional way of identifying a “Tolerable Daily Intake” using a chemical-by-chemical basis is clearly underestimating the cumulative risk of chemicals with similar structure or observable effects.

Despite the 1958 amendment requiring the FDA to evaluate cumulative effects of chemically related and biologically related substances in the diet, the agency has never performed this analysis for any chemical additives. Moreover, the FDA has not responded to citizen petitions or Congressional queries asking for the FDA to comply with the spirit and letter of this law. It simply is past time that the Agency stop ignoring the law and incorporate cumulative risk assessments in their regulatory approaches.

We ask that FDA form a committee of its Science Board including external experts to guide the agency as it addresses this shortcoming in its current safety assessment methods. When it passed the 1958 law, Congress recognized that chemicals, even ones that are not chemically related, may impact organs such as the thyroid and systems such as the cardiovascular with different mechanisms of action but cumulatively have a greater negative effect on the health of the American people.

Finally, we are happy to meet with you to provide further information and insight or to contribute to the changes that need to be made in any way that we can.

Sincerely,

Linda S. Birnbaum, Ph.D., D.A.B.T., A.T.S.
Scientist Emeritus and Former Director
National Institute of Environmental Health Sciences and National Toxicology Program
Scholar in Residence, Nicholas School of Environment, Duke University

R. Thomas Zoeller, Ph.D.
Professor Emeritus
University of Massachusetts Amherst