There is plastic everywhere in your refrigerator and pantry. There is, of course, plastic wrap, storage bags and bins, take-away containers, beverage bottles and spice containers. Plastics (synthetic polymers) are also part of the multi-layer material that makes up the chip bags and encases the granola bars. Tin, steel and aluminum cans, such as the type that might hold beans or soda, are lined with plastic. Even many paper products, like paper cups and freezer containers, are covered in (you guessed it) plastic.
So how concerned should you be about the plastic in your next meal? Is it safe?
The answer depends on several factors, experts say Popular science–but plastic panic isn’t something you can ignore and there are ways to reduce the risk of exposure.
The disturbing science of plastic exposure
Scientists have known for decades that certain compounds present in some plastics can leach from the packaging into food and eventually be ingested and absorbed. For example, bisphenol A (BPA) is known to migrate from the packaging or lining into food and accumulate in living organisms, including humans. since the 1990s. And some studies have shown potential health consequences from ingesting BPA, which may be the case mimic the hormone estrogen. Although the consequences of low-level BPA exposure are debated, recent research has shown this cognitive and behavioral effects associated with the levels found in food, especially in infants and children, says Joe Braunprofessor of epidemiology at Brown University’s School of Public Health.
In response to the research results, BPA has been phased out from some applications. It is no longer used in baby bottlesfor example, in accordance with FDA regulations. However, it still occurs in many other food packaging, such as many canned containers, and emerging research suggests that substitution compounds can be just as problematic. Such patterns have repeated themselves several times in the history of environmental health and epidemiology, Braun notes. Often, chemicals such as pesticides or flame retardants that are known to be harmful are replaced with alternatives once they have received enough negative attention. But these substitutions are usually not well studied and can prove to be just as harmful. “With the current regulatory framework, not many tests are being done on this [new] substances to know whether they are harmful,” says Braun.
In addition to BPA, there are also other chemicals such as phthalates (and their alternatives) – used as softeners and softeners to make hard plastics more flexible – are known to cause health problems ranging from premature birth to increase risk of asthma and neurodevelopmental disorders, and can enter food through packaging. PFAS (also called forever chemicals) are linked to an increased risk of cancer and are also present in plastics as a by-product of manufacturing. These also end up in food and drinks stored in plastic.
Dose is a crucial aspect when assessing the risk of exposure to chemicals. Very small amounts of some compounds can be harmless, while larger amounts can cause disease. But it is often difficult to determine exactly how much of a given substance comes from food and packaging versus another source, or whether the amount regularly ingested is enough to cause problems. Nevertheless, a January study published in the Journal of the Endocrine Society, Scientists estimate that the burden of disease from exposure to harmful chemicals in plastic is increasing hundreds of billions of dollars in medical costs for Americans over the course of one year.
More worryingly, the number of known chemicals is dwarfed by the amount of substances present in plastic food packaging, which we know much less about but which we still ingest unintentionally. A large overview study published earlier this week in the Journal of Exposure Science & Environmental Epidemiology determined that more than 3,500 chemicals found in food packaging and processing materials have entered the human body. The majority of these compounds came from food contact with plastics, but other materials such as recycled paper and cardboard also contain many chemicals known to migrate into food, says Jane Munckesenior study author and environmental toxicologist and director of the nonprofit Food Packaging Forum.
While this new research doesn’t determine whether or how each of these thousands of chemicals affects us, it does show that we are exposed to a lot in our daily diets. And that there are huge gaps in our knowledge of what that means. For example, oligomers, which are short-chain polymers that are an accidental byproduct of plastic production, are common in food packaging and processing materials, and are known to leach into food. “We don’t actually know anything about their toxicity,” says Muncke. ‘It’s worrying. That is one of the data gaps that I think needs to be studied more.”
Yet even thorough studies of isolated compounds often do not provide enough information, say both Munke and Braun, because reality is much more complex. We don’t just take one chemical at a time. Food packaging and our wider environment expose us to a chemical soup of these things, says Braun. “We know less about the impact of all these chemicals together on health than we do about each component.” So far, the few studies that exist on interactions involving multiple chemical exposures suggest that compounds can aggravate each other and that the damage accumulates, Braun notes.
What can you do?
It’s alarming to look at all the places plastic is infiltrating our food supply and the ways it could affect us. Still, eliminating all plastic from your pantry can easily become a full-time job. Instead of worrying and making yourself dizzy, there are ways to take realistic steps to minimize the risk of chemical exposure at home.
Heat, surface area, contact time and base chemistry are all useful factors to consider when making a choice about how to store food.
First things first: DO NOT MICROWAVE FOOD IN PLASTIC. “Higher temperatures facilitate the leaching of chemicals and the release of microplastics,” says Martijn Wagnera biologist who studies plastic exposure at the Norwegian University of Science and Technology. “Never microwave in plastic,” agrees Philip Landriganan epidemiologist and public health physician at Boston College. Also, don’t store hot foods, such as fresh soup from the stove, in plastic containers, says Braun.
Next, consider the relative amount of food to plastic contact. Liquids, powders and grains all have a large surface area to absorb chemicals, Muncke notes. Single-serve packaging results in a higher plastic-to-food ratio, so it’s wise to choose the bulk option whenever possible. And food stored in plastic for months is a bigger problem than something left in plastic in the refrigerator overnight or a few days. Nonperishables and pantry items, such as flour, rice and cooking liquids, are better stored long-term in glass, stainless steel or ceramic containers, she says.
Finally, foods high in fat and acid can draw more chemicals from a storage container. Oils, vinegar, cheese, tomato sauce and soft drinks are more reactive and “can be a driving force for migration,” says Muncke Popular science. Consider purchasing versions of these items that do not come in plastic or plastic-lined cans.
As a bonus, most of these changes have dual benefits: reducing the negative health risks of chemical exposure and reducing the amount of single-use plastics that end up in landfills, Braun says.
However, compromises are inevitable and plastics do have applications. For example, plastic packaging, even though it can carry some health risksare usually one of the most effective short-term storage methods to prevent food spoilage. Reducing food waste and costs are reasonable goals, and it can be difficult to find alternative storage methods that work as well and are as flexible, Braun notes. But then again, glass, ceramic, and stainless steel vessels are all reusable and chemically inert, so if you can fit your food in there, go for it. But be wary: not all reusable kitchen products live up to their sustainability claims.
Ultimately, you don’t have to be perfect to make positive changes, Muncke emphasizes. “I think the most important thing is not to drive yourself crazy,” she says. There are aspects of our individual risk of exposure to chemicals that we can control, but there are also many aspects that we cannot control. “There’s only so much you can do as a consumer.”
In the longer term, policy will need to provide a more complete solution to the risks of plastic packaging. Currently, food packaging is regulated from an “innocent until proven guilty” perspective, Braun says. Companies put chemicals in packaging and then we learn afterwards whether they are harmful, in stark contrast to the rigorous safety testing that something like pharmaceutical products must undergo before being approved for use, he adds. “I think the whole paradigm needs to be shifted.”
This story is part of Popular Science’s Ask Us Anything series, where we answer your most bizarre, mind-burning questions, from the common to the unusual. Do you have something you’ve always wanted to know? Ask us.
