Microwave your food in safe ways using safe containers. USDA advises:
“Microwave food in packaging materials only if the package directs, and then use only one time. Materials suitable for microwaving include oven bags, wax paper and plastic wrap. Do not let the plastic wrap touch the food, and do not reuse the wrap.
“Foam insulated trays and plastic wraps on fresh meats in grocery stores are not intended by the manufacturer to be heated and may melt when in contact with hot foods, allowing chemical migration into the food. In addition, chemical migration from packaging material to a food does not necessarily require direct contact. Excessive heat applied to a closed container may drive off chemical gases from the container that can contaminate the enclosed food.
“These types of plastic products should not be used in a microwave oven because they are subjected to heat when thawing or reheating. To avoid a chemical migration problem, remove meats from their packaging.” <www.fsis.usda.gov/OA/pubs/altroute.htm>
An article on “Plastics and the Microwave” in FDA Consumer magazine states, “… carryout containers from restaurants and margarine tubs should not be used in the microwave, according to the American Plastics Council. Inappropriate containers may melt or warp, which can increase the likelihood of spills and burns. Also, discard containers that hold prepared microwavable meals after you use them because they are meant for one-time use.”
The FDA article cautions: “Microwave-safe plastic wrap should be placed loosely over food so that steam can escape, and should not directly touch your food. Some plastic wraps have labels indicating that there should be a one-inch or greater space between the plastic and the food during microwave heating.”
“Always read directions,” advises FDA, “but generally, microwave-safe plastic wraps, wax paper, cooking bags, parchment paper, and white microwave-safe paper towels are safe to use. Covering food helps protect against contamination, keeps moisture in, and allows food to cook evenly. Never use plastic storage bags, grocery bags, newspapers, or aluminum foil in the microwave.”