Is It Safe to Put Plastic in the Microwave?

by WiredBerries Editors — August 9, 2007

When certain plastic containers get hot, plasticizers (the additives used to make them flexible) can dissolve into your food, which may pose health risks. Some plasticizers, such as phthalates, have been linked to reproductive problems in laboratory animals. Phthalates have been banned from children's toys by the European Parliament as possible carcinogens. But "the effect on humans isn't clear," says Anuradha Prakash, Ph.D., an associate professor of food science at Chapman University and an authority on microwaves with the Institute of Food Technologists. Phthalates are commonly found in soft plastics, like the kind meat is wrapped in, and flexible containers, such as those used for takeout food.

However, you can safely microwave food in plastic containers labeled as microwave-safe. These plastics have passed strict FDA guidelines for resilience and can withstand repeated use. If a plastic container is not clearly labeled as being microwave-safe, don't use it. It's better to err on the side of caution. As for cellophane wrap that many people lay on top of food to reheat faster and prevent splatters--don't do it. The phthalates could migrate to your dinner. Use a vented microwave-safe plastic cover instead.

In a nutshell: Toss the take-out and delicatessen containers and heat food only in plastics that are labeled microwave-safe.