We’ve all been made aware, at some point, of the fact that plastic shouldn’t go into the microwave. If you heard that and never really second-guessed it or asked WHY, the answer is that flimsy or “one-time use” plastic containers like yogurt containers will actually warp and melt in the microwave, which causes the chemicals to release in to your food. Trust me–you don’t want that.
But what about more durable plastics–like Tupperware containers or children’s plastic plateware. How can you tell which types of plastics can go in to the microwave, and which cannot? Is there a rule of thumb for determining this? And, what’s the *worst* thing that could happen if you get it wrong?
Well, to start, plastic items that are safe to put in the microwave should be marked as such because the FDA closely regulates which plastics pass certain microwave tests. Check the bottom of the bowl, plate or container–does it have a symbol that looks something like this? Does the packaging that the container came in give any indication of whether it’s safe to use in the microwave or not? (They also usually indicate things like whether they are safe for the dishwasher. If you see the dishwasher symbol, but not the microwave symbol–don’t use it).
Specifically on the topic of Tupperware–they are specific Tupperbrand brand product lines that are microwave safe: including the TupperWave Stack Cooker, Rock ‘N Serve, Vent ‘N Serve and CrystalWave. The same should go for an competing storage container brands or off-brands–just go to the brand’s website and search for which lines are microwave safe.
Lastly, if you’re concerned about whether getting any of this wrong will *kill* you–the answer is probably not. In 2008, Good Housekeeping did a test with 31 containers, lids, bags, wraps, and liners. They microwaved food in the containers, then tested the food for plastics additives. The results were very reassuring–almost none of the food contained plastic. While you should make your best effort to follow the FDA’s guidelines for safe microwaving, you don’t need to lose any sleep about it.