It’s easy to throw a plastic leftover container in the microwave to reheat last night’s dinner, but don’t do it. The chemicals in most plastics leach into the food or liquid you’re heating when you microwave them.

Try this experiment: heat water in a plastic container in the microwave. For two weeks, give your houseplant that water. It will die. Take this as the canary in the mineshaft: if it kills a plant, do you want to gamble that it won’t hurt your infant & newborn?

It is also possible that some chemicals in these containers may transfer into the food. Whether this is enough to cause any risk to health has not been determined,“ reads a section of the report, Chemicals Migrating from Food Contact Surfaces, Food Council News, 2003.

To play it safe until more is known about microwaving plastic, follow these basic guidelines:

•     Do not use plastic bowls or wrap in the microwave unless they are labeled as microwave safe. The U.S. FDA suggests that heating food with labeling instructions for heating in the package or storage containers qualify as “microwave safe.”

•     If plastic containers are re-used as storage, let the food cool before storing, then refrigerate it immediately. Avoid visibly damaged, stained or unpleasant smelling plastics and containers.

•     Never heat or store food in plastic containers that were not intended for food. One-time use containers, like margarine tubs, tend to warp or melt in the microwave, and this may allow more of the substances in plastic to migrate into the food.