Is Plastic Box Healthy And Safe?-www.china-tin-boxes.com
According to the FDA, you should only use plastic box that have been labeled for microwave oven use. A container fits this category if it is labeled “microwave safe,” if the package contains an image of a microwave, or if the instructions direct you to use the microwave.
If you don't see any indication that the plastic box is safe for the microwave, you may want to reconsider nuking it. The FDA says that some plastics run the risk of melting in the microwave.
One threat surrounding plastic containers that's gotten a lot of attention in recent years is a chemical called bisphenol-A (BPA). The National Institute Of Environmental Health Sciences says that BPA can leach into food from food plastic box containers.