Home ยป Microwaving plastic…hmmm…

Microwaving plastic…hmmm…

Lily and I are flying solo this week, as Mark is at headquarters for business. The last thing I wanted to do last night was cook, so I popped in a SmartOnes — SantaFe Style Rice and Beans, I believe it was called. Anyways, those things don’t fill up this heifer, so I decided to add in more corn…which I happened to have in one of those steamable bags. I read the directions: 4-5 minutes on high. Now, I admit, I reheat leftovers in tupperware which I’ve been told is bad (but is it?!)…but the steamables bag…that just seemed way more wrong than my reheating-in-tupperware laziness. So, of course, I researched this morning as I sipped my daily vice: cappuccino. As for me and my tupperware, I am in luck. The FDA approves microwave-safe plasticware for chemical leaching onto food when heated. Any plastic products emitting unsafe amounts of chemicals onto foods are deemed unsafe for retail sale. And what about those leftover fajitas sitting in Styrofoam I plan to eat for lunch? Well, those can likely be reheated in the same fashion [1].

Similarly, Mayo Clinic dietitian, Katherine Zeratsky, discussed this same topic in a January 2009 article on the heating of plastic and the release of dioxins. Firstly, dioxins are cancer-causing substances found in soil, water, and animal fat. They are commonly created from forest fires and the burning of household trash. Reheating food in plastic, however, is also discussed as being safe from this credible source, as well [2]. The American Cancer Society concurs, too. So…

Microwave safety tips [1]:

– If you’re like my family and think anything with a lid is reusable storage, please be advised that margarine tubs, cottage cheese tubs, yogurt containers, and plastics of the like are typically NOT microwave-safe

– If you’re not sure whether or not a plastic is microwave-safe, play it safe and transfer it to a plate or glass dish – Remember to vent or leave open a jar any plasticware being reheated

– Use wax or parchment paper when reheating food on a plate rather than plastic wrap — plastic wrap, while being heated, should not touch food

I’m glad my corn-bulked meal was A-okay, and now I’m even more-so looking forward to those fajitas at lunchtime…reheated in styrofoam.

[1]. Microwaving Food In Plastic: Safe or Not? The Harvard Medical School Family Health Guide. July 2006.
[2]. Zeratsky, Katherine. Does Microwaving Plastic Food Containers Cause them to Leach Dioxins into Food? MayoClinic. January 2009.

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  1. Jim Purdy
    July 22, 2009 / 11:59 pm

    Yeah, but is microwaving safe? What about the skeptics who think microwaving is unhealthy?

  2. Nicole M., MS, RD, LD
    July 23, 2009 / 12:25 am

    Hi Jim,Here's an excerpt from the FDA on microwave safety:A Federal standard limits the amount of microwaves that can leak from an oven throughout its lifetime to 5 milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface. This limit is far below the level known to harm people. Microwave energy also decreases dramatically as you move away from the source of radiation. A measurement made 20 inches from an oven would be approximately one one-hundredth of value measured at 2 inches.

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