The vast majority of the chemicals examined—87 percent, or more than 13,200—lack enough accessible information to estimate their risks.Charly Triballeau/AFP via Getty
This story was originally published by Inside Climate News and is reproduced here as part of the Climate Desk collaboration.
Most people decide if it’s safe to eat an old tub of yogurt in the fridge or canned tuna in the back of the cupboard by checking its sell-by date. But no label indicates that pesticides, phthalates, PFAS, or other hazardous chemicals could be seeping from those containers into your food.
Of more than 15,000 chemicals that come in contact with food, a new peer-reviewed study found, 1,222 pose serious health risks such as cancer and reproductive harm. And the vast majority—87 percent, or more than 13,200—lack enough accessible information to even estimate their risks.
The fact that there’s not enough publicly available information for independent scientists to assess the safety of chemicals that can contaminate food is “the elephant in the room,” said study co-author Jane Muncke, managing director at the nonprofit Food Packaging Forum Foundation, which led the research, published Tuesday in the journal Environmental Science & Technology.
In the new paper, they analyzed that “jaw-dropping” number of chemicals, Muncke said, to flag the most problematic.
Consumers trust that when regulators allow chemicals in products like food packaging, it’s because it’s been through safety testing, Muncke said. “But that’s not the case,” she said. “And it doesn’t make sense.”
The team has done a “very, very good job” highlighting how little is known about the risks of substances that affect everyone, said Maricel Maffini, an independent chemical safety and regulation expert who was not involved in the study but has collaborated with Muncke in the past.
Because the study focused on a list that people in industry and regulators regard as reliable, it’s looking under the proverbial lamppost, Maffini said. While there’s plenty of information suggesting that many of these chemicals should not be on the market or should have stronger regulations, she said, there’s so much information beyond that list that’s missing.
In previous work, Muncke and her team identified more than 15,000 chemicals used in food processing or packaging from lists of substances approved by regulators in the United States, China, Japan, and countries in Europe and South America or that had been identified in studies. In the new paper, they analyzed that “jaw-dropping” number of chemicals, Muncke said, to flag the most problematic.
To maximize the utility of their priority list, the team used only data obtained from governmental and regulatory agencies linking a chemical to human health hazards such as cancer, reproductive harm ,or ability to concentrate in the body.
That yielded a priority list of 1,222 chemicals that they ranked into four tiers, with the highest to lowest evidence of human exposure from food-contact materials. Ninety-four chemicals known to seep into food and detected in breast milk, blood, or other human samples were assigned to Tier 1, the highest priority for regulators and companies to consider phasing out.
These chemicals include liver- and immune system-damaging PFAS “forever chemicals,” which make food wrappers grease- or water-resistant; the likely carcinogen styrene, used to produce takeout packages and refrigerated dairy food containers; hormone-disrupting phthalates, added to make plastics like those that hold vegetable oils flexible; and bisphenol A, added to hard plastics and can linings and a poster child for endocrine disruptors’ ability to impair development at low doses.
Studies have found these and other chemicals leaching from containers into a diverse array of food and beverages, including water, infant formula, orange juice, ice cream, yogurt and cream, oils, cake, and fatty foods.
The next highest priority list, Tier 2, included an additional 264 hazardous chemicals that leach into food but have not been detected in biomonitoring studies. At least, not yet.
Muncke is particularly concerned about babies’ exposure to plastic chemicals in pouches that hold juices and pureed food.
The chemicals in Tier 1 provide the most reliable evidence that materials that come in contact with food are a source of people’s exposure to these chemicals, Muncke said. The chemicals are in people, they’re in food and they’re in food-contact materials, she said. “What more proof do you want?”
Inside Climate News asked the American Chemistry Council and Food Packaging Coalition, trade groups that represent the chemical and food-packing industries, if their members would release hazard information about the chemicals they use and phase out those known to be hazardous. Neither responded, but the Food Packaging Coalition maintains that packaging is designed to prevent the transfer of its components to food and to ensure that they are safe and suitable for their intended use.
The paper offers a practical and transparent roadmap for using the best available evidence to prioritize food-contact chemicals for regulation, said Sara Lupolt, an expert on exposure assessment at Johns Hopkins Bloomberg School of Public Health, who was not involved in the research.
Though not addressed in the paper, she added, more research is needed to determine which foods and chemical combinations result in more chemicals moving into food.
Many of the chemicals that migrate into food are so-called non-intentionally added substances, or NIAS. Their identity is often obscure because existing tools can’t identify every chemical in use, especially when researchers don’t know what to look for because producers keep proprietary chemical ingredients secret.
Muncke is particularly concerned about babies’ exposure to plastic chemicals in pouches that hold juices and pureed food. Earlier this year, her team found evidence that more than 330 chemicals leach from pouches, including nearly 80 known to be hazardous. They presented the findings at an event at the House of Lords in the United Kingdom in June.
At a minimum, the paper argues, chemicals that have structural similarities with others known to be hazardous should be priorities for regulation.
A greater volume of chemicals get into baby food because the ratio of packaging to food is much greater in a small serving size, Muncke said. And the pouches are sterilized using heat, which drives chemicals to migrate and forms microplastics.
Several peer-reviewed studies, including a 2023 Chemosphere study, also found chemicals, including NIAS, in baby food packaged in pouches. The paper’s authors believed the NAIS, which lacked adequate information to assess risk, were impurities and raw materials from producing plastic. “Infants may be constantly exposed to NIAS via consuming pouched food products,” the authors warned.
For the 87 percent of chemicals that lack hazard data, it’s primarily a question of the data not being public, said study co-author Helene Wiesinger, a chemist and Food Packaging Forum scientific officer.
That delays regulatory action, Wiesinger said, because governments and independent scientists must first figure out which chemicals are safe. She believes a product or chemical should not be allowed on the market until a company can prove that it’s safe.
At a minimum, chemicals that have structural similarities with others known to be hazardous should be priorities for regulation, the paper argues. Seventy percent of the more than 4,200 chemicals the team classified into 38 priority groups—including PFAS, phthalates, and organophosphates (used as flame retardants and pesticides, among other applications)—lack enough data to assess potential harms.
Just because something isn’t yet known to be hazardous doesn’t mean it’s not hazardous, said Wiesinger. Time and again, chemicals found to present unreasonable risks are replaced with others that have similar properties and ultimately similar risks.
“We hope this work provides practical guidance on how to at least not make the very obvious mistakes,” she said.