Should I be concerned if a microwave-safe plate gets hot in the microwave?”
However, not all glass and ceramics are microwave-safe. NOTE: Here’s a quick test for glass: Microwave the empty container for one minute. It’s unsafe for the microwave if it’s warm; it’s safe for reheating if it’s lukewarm; and it’s safe for actual cooking if it’s cool. In the US, the FDA [www.fda.gov] mandates tests of food safe papers, plastics, and inks in packaging. They are primarily concerned with possible toxic materials that might leach from the packaging into the food, especially at high temperature. If a material, adhesive, or ink does not heat in the microwave, then it is microwave safe. It is a simple matter to check on these materials as you do at home. In addition, microwave heating can be predicted by the prescence of ionic (e.g. salt in water), or polar materials (e.g. water) which heat vs non-polar materials (paper, most plastics, most glasses, china, etc) which don’t heat. In some cases, manufacturers will deliberately include materials that absorb microwave energy a
I work for a company that is a plastics compounder – which means they getplastic directly from the nuclear power plants that cook it out of petroleum, mix it into different forms, and then ship it out to other companies that make products. The chemists that design the melts (plastic recipe runs) refuse to use ‘microwave safe’ or any other plastic containers in a food settling where the container gets hot. The plastics that are labeled ‘safe’ for such conditions are the same plastics that would normally be unsafe, mixed with a strengthening additive. When, over the course of time and exposure to heat & other radiation, the plastic itself does not break down rapidly, but instead the additive ‘takes the hit’ and comes out of the container (with small quantities of plsatic). The problem is that the strengthening additives are highly toxic – with various kinds having known connection with organ failures and nervous system problems. The safety tests done on the plastic compounds I’ve been ab
