Is it safe to heat food in plastic containers or use plastic wrap in the microwave or oven? In 2016, President Obama signed a law strengthening the Toxic Substances Control Act, which requires chemicals to be tested to ensure they are safe. Before the law was enacted, there were more than 60,000 untested chemicals on the market. Because of the size of the backlog, it could take decades for the EPA to test the thousands of chemicals in widespread use today. So, let's look at this question more closely.
What harmful chemicals, if any, do plastics contain? The two main chemicals to watch out for are phthalates (used to soften plastics) and bisphenol A (BPA), which is used to make very hard, shatterproof plastics (which often have a # on the bottom) 7), also found in car interior linings. Canned food and beverages.
When phthalates and BPA enter our bodies, they can affect estrogen or testosterone. BPA, phthalates, and other chemicals known as endocrine disruptors act like hormones in our bodies, affecting the production of our natural hormones. These types of chemicals have been linked to cancer, reproductive organ problems, and several other health issues.
Additionally, a 2023 study found that children who were exposed to phthalates in utero or in their first year of life were more likely to develop phthalates. Behavioral, attention and learning disorders. That's why six phthalates are legally banned from children's products, and why the FDA is studying BPA to determine whether it should be banned from baby bottles and the linings of food and beverage cans.
Plastic wrap has been "phthalate-free" since 2006, but in the United States it is made from polyvinyl chloride, or PVC, and contains a chemical called di(2-ethylhexyl) adipate "Plasticizer" of ester or DEHA. DEHA is not a phthalate, but its chemical properties are very similar to a phthalate called DEHP.
Research in the 1990s showed that DEHA can cause liver tumors in mice, and other studies have shown that DEHA can migrate from plastic wrap into food, especially high-fat foods such as cheese. A 1998 study by Consumers Union tested plastic-packaged food and found DEHA levels higher than recommended or even allowed by European advisory committees and regulatory agencies. A 2014 study found DEHA in various cheeses, as well as beef, chicken and pork, sold in plastic wrap at grocery stores. A 2021 study found that DEHA caused brain and heart damage in rats, but research is needed to better understand the risks to humans.
Likewise, high-density polyethylene (HDPE) plastic containers—commonly used to store household cleaners and pesticides but sometimes also used to store food—tested positive for PFAS. Results from a 2023 experiment showed that PFAS can transfer into food, and if PFAS is present in your food storage, it can transfer into your food over time. Researchers tested olive oil, ketchup and mayonnaise and found that all contained detectable levels of PFAS after a week of exposure to HDPE. While HDPE is not currently suitable for food storage, there is nothing stopping plastic companies from using them in this way. This could expose thousands of people to potentially dangerous levels of PFAS.
Many foods are sold in plastic containers, and most of us store our leftovers in food storage containers made of plastic, such as Tupperware, Rubbermaid, and other brands, as well as in restaurant to-go containers. While none of these containers appear to be made with phthalates (as they are generally relatively soft), some may contain BPA. As companies become more aware of the dangers of the plastics they use, they replace some chemicals with others. When looking at Rubbermaid's website, it states that the company does not currently make products that contain BPA or phthalates. Tupperware says that as of 2010, all of its products are BPA-free, but any older products may still contain some level of BPA. If you want to check if your Tupperware is BPA-free, check the bottom of the container. Any number from 1 to 6 means the product is BPA-free, but 7 means the product may contain BPA. Additionally, the companies that make plastic wrap have changed the chemicals in their products to make them less sticky but also less dangerous to our planet.
Regardless of whether plastic food containers contain phthalates or BPA, it may not be completely safe. Plastics break down over time, which means they may release trace amounts of chemicals into food. This is more likely to happen when the plastic is heated or old and has been reused or washed. In fact, numerous studies show that most humans contain microplastics, often from the food and drinks we consume every day. Perhaps these chemicals are harmless, but there are no studies showing the cumulative effects of regularly consuming food stored or heated in these plastic containers. It's not surprising to find out that they may not be as safe as many of us thought.
So what about those foods we buy that are labeled as microwaveable in the plastic containers they are sold in?
The plastic is said to be "microwave safe," but that means it won't melt in a microwave, but that doesn't mean it won't release small amounts of chemicals into your food. Anything not labeled "microwave safe" will soften and lose its shape in the microwave. "To-go" food containers or other disposable plastic food containers are particularly unsafe to use in a microwave.
Researchers microwaved food in a variety of plastic containers marked with microwave-safe labels and found no detectable levels of BPA, or phthalates, in most of the containers. But if your favorite container contains these chemicals, in addition to all other ways you could be exposed to endocrine-disrupting chemicals and microplastics, you could end up with unhealthy levels of these chemicals in your body.
We need more research to understand which plastics are safe—under what conditions and for what uses. Until we have this information, you can "err on the side of caution" and reduce the amount of chemicals in plastic that get into your food by following these tips:
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Avoid letting the plastic wrap come into contact with food, especially when it is being heated or when the food is high in fat (such as meat or cheese). If you want to prevent food from coming into contact with the plastic wrap to prevent splatters in the microwave, cover it with a microwave-safe plate or paper towel.
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Use glass or ceramic containers for microwaving food and drinks and avoid using plastic or disposable containers for microwaving.
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While 96% of canned goods from major supermarkets tested in 2019 were BPA-free, you may want to throw away older cans at home as their linings may still contain BPA.
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Look for drinks sold in cartons or glass bottles. The lids of some glass bottles may be lined with BPA, but even then, the top usually doesn't come into contact with the drink. If you carry a reusable water bottle, switch to a stainless steel water bottle or make sure your sports water bottle is "BPA-free." Plastics containing BPA are often hard and will make a clicking sound if you hit them with your fingernail or a fork or other metal utensil, and may have the number seven on the bottom.
Remember, all plastics break down when exposed to heat (either in the microwave or dishwasher) and when exposed to strong soaps. Cracks and cloudiness are signs that clear, reusable plastic containers have begun to break down and may release BPA or other chemicals into your drinks or food.
