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Practices -- Cooking
Can you safely microwave vegetables in a plastic storage bag?
It is best not to do this because there has been insufficient research to determine how risky this practice is. Plasticizers - chemicals used by some manufacturers of food wraps and other pliable plastic products - belong to a class of substances known to cause abnormalities in animals. Research is being conducted to determine if exposure to plasticizers is associated with low sperm counts, blunted IQ's, and other problems. At the time, there is no conclusive evidence to say yes or no. To be safe, do not microwave food in plastic bags that are not labeled for microwave use. Tests done by Consumer Reports found that plasticizers did indeed migrate to foods when heated, but only where food came in contact with plastic. (High fat foods like cheese tended to absorb other chemicals found in the plastic.) Manufacturers thus recommend leaving a gap between food and plastic when heating, which is not possible with a storage bag. Consumer Reports did not find plasticizers in microwaveable Rubbermaid(tm) and Tupperware(tm) bowls. Thus, only microwave foods in microwave-safe containers. Also do not use plastic bags for reheating foods in water on the stovetop. Under these high temperature conditions, the plastic could break down allowing the plasticizers to migrate into the food.