Rubbermaid food storage containers are made from various types of plastic -- or glass -- which are all designed to be microwave-safe. You should still take a few precautions before heating up your food in a Rubbermaid container though. It can make a mess or be problematic in some cases.
What to Look For
If you have an older Rubbermaid dish lying around or if you're unsure if your specific container is microwave-friendly, look at the bottom. It should say "microwave safe" or have a design of a microwave displaying the word "reheat." The manufacturer designed these types of products to be microwave-safe.
Before putting the Rubbermaid container in the microwave, remove the lid, or open up the corners for ventilation. If you microwave food with a sealed-on lid, pressure can cause the lid to pop off during cooking, making a mess. Be cautious while removing the dish from your microwave after heating. Plastic food storage containers get hot fast, which could burn you.
Microwaving food in plastic containers may be a concern for some. Bisphenol A, or BPA, in plastic has been shown to be harmful to a growing fetus or young child in animal studies, the National Institute of Environmental Health Sciences reports. Older lines of Rubbermaid, such as the Premier or Easy Find Lids, were made with BPA-containing plastic. However, independent studies showed that the compound did not leach into food. As of 2009, Rubbermaid updated their products so that they are made with BPA-free plastic.