ZipLock Omelet

One woman said this was a Girl Scout technique, but I never learned it in my Girl Scouts.

nm46: I think I understand your concern.

So here's a caveat: Do not use this recipie if you think it might be hazardous for your health!!!

But I don't think that venting is a hazard - it is less likely to explode as boiling an egg, because the bag is flexible, and, unlike microwaves, the omelet is cooking from the outside in, not possibly the inside out. Obviously, the omelet is at most as hot as boiling water when you remove it from the bag so you don't want to drop it on your lap.

If you don't want to cook this way, then you may want to be thinking twice about microwaving in plastic. Note also, the omelet cannot get at a higher temperature than boiling water, and that most foods that boil (besides water) boil at a higher temperature than plain boiling water (from your Chemistry 101 Boiling point elevation). Think the caution we use when boiling fat or boiling sugar when making candy. It gets at a much hotter temperature than boiling water.

One box of Glad zipper bags in my kitchen says 'when microwaving, open zipper 1 inch to vent and place bag on a plate.' So it sounds like some zipper bags can be heated to a temperature higher than boiling water. I have no association with the Glad company or any inside information with the FDA.

I used a generic brand in my test, and the bag did NOT melt or break (until I cut it open with my scissors.) I don't know if I could have exposed myself to phthalates because this generic brand does not specify it can be heated. So Buyer Beware. This is the first omelet I've eaten in at least 2 years.

Here's what Snopes says about it.
http://www.snopes.com/medical/toxins/cookplastic.asp

And one of their references:

So it’s okay for people to drink out of plastic water bottles?

RH: First, people should be more concerned about the quality of the water they are drinking rather than the container it’s coming from. Many people do not feel comfortable drinking tap water, so they buy bottled water instead. The truth is that city water is much more highly regulated and monitored for quality. Bottled water is not. It can legally contain many things we would not tolerate in municipal drinking water.

Having said this, there is another group of chemicals, called phthalates that are sometimes added to plastics to make them flexible and less brittle. Phthalates are environmental contaminants that can exhibit hormone-like behavior by acting as endocrine disruptors in humans and animals. If you heat up plastics, you could increase the leaching of phthalates from the containers into water and food.
What about cooking with plastics?

RH: In general, whenever you heat something you increase the likelihood of pulling chemicals out. Chemicals can be released from plastic packaging materials like the kinds used in some microwave meals. Some drinking straws say on the label “not for hot beverages.” Most people think the warning is because someone might be burned. If you put that straw into a boiling cup of hot coffee, you basically have a hot water extraction going on, where the chemicals in the straw are being extracted into your nice cup of coffee. We use the same process in the lab to extract chemicals from materials we want to analyze.

If you are cooking with plastics or using plastic utensils, the best thing to do is to follow the directions and only use plastics that are specifically meant for cooking. Inert containers are best, for example heat-resistant glass, ceramics and good old stainless steel.

Is there anything else you want to add?

RH: Don’t be afraid of drinking water. It is very important to drink adequate amounts of water and, by the way that’s in addition to all the coffee, beer and other diuretics we love to consume. Unless you are drinking really bad water, you are more likely to suffer from the adverse effects of dehydration than from the minuscule amounts of chemical contaminants present in your water supply. Relatively speaking, the risk from exposure to microbial contaminants is much greater than that from chemicals.

And here’s one more uncomfortable fact. Each of us already carries a certain body burden of dioxins regardless of how and what we eat. If you look hard enough, you’ll find traces of dioxins in pretty much every place on earth. Paracelsus the famous medieval alchemist, used to put it straight and simple: it’s the dose that makes the poison.

http://www.bms.jhmi.edu/JHI/English/Media/Find_an_Expert/FE_RolfHaldenJuly05.asp