Can You Microwave Plastic?

July 9, 2015

After a long day, sometimes all you wanna do is grab some something from the freezer, nuke it, feed the family, and call it a night.

But for many of us, there’s a nagging worry: Are those little ovens actually safe?

The answer is more complicated than it might seem on the surface. The good news is, the microwave itself isn’t the bad guy. Although microwave technology relies on scary-sounding electromagnetic radiation—waves that absorb food and vibrate its water molecules, creating thermal energy—the process itself is quite safe.

Those waves are a non-ionizing form of radiation, meaning they’re low-frequency and are not charged enough to damage human DNA. We come in contact with these waves every day via radios, televisions, even our computer screens. And the notion that they cause cancer? Totally unsubstantiated.

But there is bad news, and it centers around the plastic bowls, plates, and containers you’re microwaving your food in. Turns out, they’re leeching harmful chemicals into your food.

A recent study from the NYU Langone Medical Center found troubling levels of phthalates in the urine of children. Phthalates are used in soap, cosmetics, shower curtains, and processed food containers, and are believed to interfere with endocrine functions and correlate with a higher risk of hypertension and type 1 diabetes.

Fortunately, the FDA does closely regulate the use of plastics that come into contact with food. When you see ‘Microwave Safe’ on a food package, it really is.

However, if you see the recycling numbers 3, 6, or 7 (inside the triangular recycling symbol) on any type of plastic container (including drinks), toss them—it indicates that they were manufactured with these chemicals, which could be harmful when in contact with food, whether you’re microwaving it or not.

If your container doesn’t have a number or a label,  keep it out of the microwave and dishwasher. And if it’s a little nicked up, just throw it out. Scratches mean the protective coating has broken down, leaving your food vulnerable to chemical absorption. Whenever possible, opt for stainless steel or glass containers.

Bottom line? Popping a healthy meal into the microwave isn’t a bad thing. Just be sure to use safe containers so you can get your quick meal without a side of chemicals.

Photo credit: alexunderwood910 via Flickr

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Dana Poblete

Dana's love for all creatures under the sun (bugs, too) drives her in her advocacy for ethical eating, environmental sustainability, and cruelty-free living. A natural born islander, she surfs when she can, and writes, always.

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