Experts are warning that the everyday habit of microwaving food in plastic containers could increase the risk of cancer and other diseases. While many people heat delivery containers or leftover food storage containers as they are for convenience, specialists caution that chemicals in the containers can migrate into food.
Dr. Brian Helfand, a urologic oncology specialist in the United States, said in a recent interview with health publication Parade, "While cancer risk can't be entirely controlled, knowing which everyday habits can influence that risk can help you make smarter choices." He added, "In particular, microwaving food in plastic containers is a prime example of a habit to avoid."
When plastic containers are heated in a microwave, chemicals such as bisphenol A (BPA), phthalates and styrene can leach into food. "Repeated exposure to these substances can disrupt hormonal function or cause cellular damage," Dr. Helfand explained.
Microwaves generate heat by rapidly vibrating water molecules in food. During this process, tiny particles including microplastics can transfer into the food.
"Especially when old or scratched containers are used, or when high-fat foods are heated at high temperatures, plastic particles seep into food more easily," Dr. Helfand warned.
A recent study by researchers at the University of California, San Francisco School of Medicine analyzed the link between microplastics and various cancers. The findings suggested that microplastic exposure may be associated with certain cancers including colorectal and lung cancer.
"Many people use plastic containers in the microwave because of convenience," Dr. Helfand noted. "Some believe that a microwave-safe label means it is completely safe, but the possibility of chemical leaching cannot be entirely ruled out."
Experts recommend switching containers as the most effective way to reduce exposure. When reheating food, transferring it to glass, ceramic or porcelain containers is advisable. Using microwave-safe covers or paper towels instead of plastic wrap is also recommended.
People should also avoid reheating food directly in delivery containers or disposable plastics. For storing hot food, glass or stainless steel containers are suitable. Choosing fresh or frozen foods over heavily packaged processed foods, avoiding hot beverages in plastic bottles and replacing scratched or worn containers can also help reduce exposure.
"There is no need to be overly anxious about occasional exposure," Dr. Helfand said. "Since cancer risk is heavily influenced by long-term repeated exposure, making small, consistent changes over time can significantly lower the potential risk."