5 Questions on Food Additives with Scientist Dr. Maricel Maffini

5 Questions on Food Additives with Scientist Dr. Maricel Maffini

January 5, 2023

By Alexandra Zissu, Editorial Director

A new study in the January issue of Reproductive Toxicology finds that many of the chemical additives in the food we eat lack adequate safety data, and some have no data at all. To learn more about this disturbing discovery, we got in touch with study author Dr. Maricel Maffini, Senior Scientist at the Natural Resources Defense Council.

1. Let’s start at the beginning—what’s the extent of the problem?
One of my first surprises was to learn that there are more than 10,000 chemicals allowed in our food. Roughly half of these are purposely added, and they are called direct additives. The other half are chemicals that get into the food through the manufacturing process or the packaging. These are called indirect additives or food contact substances.
When we looked in the published literature to see how many had been tested, for example by feeding them to animals to find out whether they cause any harm, we didn’t find information for more than two-thirds of FDA-regulated additives. The FDA’s own database had many holes—only 36 percent were fed to lab animals to study their effects.

2. How is it that manufacturers can put so many untested ingredients into our food?
Many of these chemicals were approved decades ago with little or no toxicity testing data, [and] the FDA doesn’t look back and review previous decisions. Once a decision to allow a chemical in the food supply is made, it’s forever. The agency only reviews the safety of an approved chemical in response to a serious health concern. It doesn’t systematically review old decisions even though newer evidence may question the safety of some of those chemicals. And with so many additives without data to start with, it’s very difficult to link a health problem to a specific chemical or group of chemicals.

3. Should we even trust those ingredients that have been tested?
FDA recommends that direct additives be fed to lab animals for at least 28 days. Of the roughly 1400 direct additives for which we found feeding data, only 852 were fed to lab animals to figure out how much we could eat before getting sick. The rest were tested by checking how much of a chemical can kill half of the testing animals. Needless to say, counting dead bodies is a pretty inappropriate way to determine the safety of a chemical. More importantly, of those chemicals that FDA guidance recommends testing for reproductive and developmental toxicity, only 137 of 1136 chemicals had that information.

Indirect additives or food contact substances are not subjected to the same testing. If a manufacturer estimates that the amount of a food contact substance that will get in the diet is below an established exposure threshold, FDA doesn’t recommend any testing at all.

But, even if all chemicals in food were studied using the recommended testing, the methods the FDA uses, [which were] innovative in the 1970s and 1980s, now is outdated. For instance, it doesn’t recommend screening for endocrine disruption or behavioral effects; it doesn’t routinely consider exposure to children and pregnant women or testing for allergic reactions; and it assumes that small amounts of chemicals don’t cause adverse effects.

4. What’s the difference between additives that are “Generally Recognized As Safe (GRAS)” and other food additives?
When Congress passed the Food Additives Amendment of 1958 that established the regulatory framework for chemicals in food, it included a loophole for common ingredients. Companies making ingredients such as vinegar and cooking oil didn’t have to test them as long as the scientific community agreed they were “generally recognized as safe” or have been used for a long time without problems. The rest would be food additives [with] their safety determined by FDA.

Congress was clear that the safety standard is the same for GRAS substances and food additives: scientists should be reasonably certain that the lifetime exposure to the chemical will cause no harm. The difference is who makes the safety decision. FDA decides whether a food additive is safe; companies decide whether a substance is GRAS. FDA interpreted the law to say that the GRAS exemption permits a company to make a GRAS decision and not tell the agency. This means that a company can develop a chemical, determine that it is GRAS, and use it in food without FDA or the public having any idea about its presence. We estimated that there are at least 1,000 GRAS chemicals unknown to FDA.

5. What advice do you have for parents trying to serve safe meals?
Making lunch and dinner from scratch would be a way to limit exposure to food additives. Taking a closer look at the labels may help, but even I find myself lost in a sea of unpronounceable words. Besides, chemicals that get into the food from packaging will never show up in a label.

We, as consumers, should not be responsible for deciding what’s safe to eat. It is Congress’ and FDA’s responsibility to keep the public safe by ensuring the safety of our food. At NRDC, we’ll work to strengthen [this] oversight. Help us press the government to do its job.