Can you microwave plastic? Plastic is a synthetic or semi-synthetic material that’s durable, lightweight, and flexible. This article explains whether you can safely microwave plastic. To know if a plastic container or plastic wrap is microwave safe, you should look on the packaging material for a “Microwave Safe” label. Plastic products with an imprinted microwave symbol can be used in the microwave. This symbol is mostly used on reusable plastic storage containers. There is only one way to verify if the Tupperware receptacle is certified safe for microwave use. Check the bottom of the container and look for the microwave safe symbol comprised of 3 wavy lines.