I started this thread because of a debate on reddit between me and another redditor. They keep insisting that it’s very bad, and then I’ll ask for a cite and they’ll say classic redditor stuff like google it yourself, I’m not doing your work for you.
The thing is, I did google it myself, several times, and I can find nothing about any health risks from microwaving frozen dinners in the plastic trays they come in. (I mean, obviously they aren’t exactly health food, but speaking in terms of microplastics.)
Their position is that they are very bad for you even in small quantities. But more specifically to your point here, they insist that “microwave safe plastic” only means that it won’t bubble and burn from the microwave. You still get tons of microplastics from them. I asked for a cite, he links that stupid “here’s how to google” thing where it shows an image of google and moving the mouse to the search bar. Super annoying.
So anyway, my curiosity was raised so I brought it here where the discourse is on a much higher level. But for your question, I have it on the unimpeachable authority of “trust me, bro” that microwave safe plastics are pretty much the worst thing in the world for your health if you heat them up in the microwave.
EDIT: They also claimed that frozen dinners are banned in several countries. When I asked for a cite for that crazy claim, they linked a “plastic bans” page focused solely on environmental pollution. ie: Plastic grocery bags, plastic straws, etc… No mention of microwave dinners. So once again, infuriating reddit stuff.
The whole debate is over the significance of the plastic on the health of consumers. As far as we know, it’s all insignificant (until studies show otherwise).
(That being said I’m sure you’re correct on your specific point here.)
If that redditor was correct, some personal injury attorney should probably be able to win a massive lawsuit, as previously occurred with previous cases like the talcum powder one.
And ironically that redditor would not even get any of the money from that case.
Could be, but then, maybe not - sous vide tends to be done in bags made of plain LDPE with no plasticisers or other additives, and they are only heated to some temperature that is way below the boiling point of water and thus also even more below the decomposition temperature of the plastic resin.
Plastic containers of food heated in a microwave can easily experience spot heating above the decomposition temperature of the plastic itself - especially when hot fats are in direct contact with the plastic, or where steam is present and is still being heated by the microwaves before it escapes. I’ve seen ‘microwave safe’ plastic containers acquire melted spots in such conditions and if the plastic is actually being melted, it’s far more likely for the component chemicals to be escaping into the food.
I just want to point out (as I think has been at least suggested) that it’s not just micro- and nano-plastics that can be released by heating plastic containers. There are many additives to plastics, most notably plasticizers, but also anti-oxidizers, colorants, and other assorted chemicals, which can easily leach out into foods, especially under heating.
I had a co-worker who absolutely refused to store her food in plastic containers, and would never, ever microwave anything in plastic containers. She regularly preached to us the likely contamination of our food by such practices.
PFAS was mentioned earlier. It was a familiar term but I couldn’t immediately quite place it. Now I remember. It was from the movie Dark Waters, an account of a massive real-life class action lawsuit against the DuPont chemical company for the harm and deaths caused by the related chemical PFOA, which up until 2010 was used in the manufacture of Teflon. PFOA is a so-called “forever chemical” that is very difficult to break down, and mainly due to DuPont, today virtually every living creature on the planet has some amount of PFOA in their bloodstream.
PFAS is an abbreviation for a broad class of what are called perfluoroalkyl and polyfluoroalkyl substances, and PFOA (perfluorooctanoic acid) is a type of PFAS. PFAS substances have long been a health concern, though some are more toxic than others. This article from the American Cancer Society has more information:
One other point to keep in mind about PFAS chemicals is that there’s a distinction between those chemicals being used in the manufacture of non-stick coatings, and those coatings actually containing PFAS. In the case of Teflon, for example, to the best of my knowledge Teflon doesn’t contain PFOA and never did, even when it was still being used in its manufacture. The hazards came from the manufacturing process and the workers who were exposed to PFOA, and, significantly, from DuPont’s grossly irresponsible disposal practices of the manufacturing byproducts, wherein they started a chain of events that essentially polluted the entire planet.
That said, there are other reasons to be cautious about Teflon and similar non-stick coatings and to avoid overheating them.
Anyway, back to the main topic, there are a great many unknowns here. My practice is mostly common sense. I have no problem with microwaving commercially prepared foods in plastic containers that are designed for it, but I regard them as single-use and recycle them afterwards.
I never microwave anything in plastic containers not explicitly intended for that purpose, and if at all possible I avoid using plastic wrap in the microwave, but if absolutely necessary I make sure it doesn’t directly contact the food. And I think it’s reasonable to assume that microwaving food in a plastic container intended for that purpose is safer than heating it in the oven, because it spends a much shorter time in there and the food is heated directly, whereas in the oven it’s heated from the outside in, through the plastic, and for a much longer time.
I’ve never heard of PFAS as an additive to plastics. As you mention, things like PFOA are precursors for Teflon (PTFE), but I don’t know if any remains after the Teflon has been manufactured I never thought it was, but it could conceivably be contained within the mas of the Teflon.
I feel like it really wouldn’t be all that hard to demonstrate in a lab, assuming we have technology that can measure the amount of microplastics in food.
Take two different commercially produced microwave products with plastic trays. Let one thaw to room temperature on the counter, heat the other one up in the microwave as directed. Mix both samples (separately) until they are a uniform goop and then measure the microplastics in both.
Is “big TV dinner” the equivalent to big tobacco, suppressing any such research? Remembering back to that John Travolta movie where the small town lawyer sues Beatrice Foods Company, maybe?
Not “Big TV dinner” but “Big Chemical” (i.e. du Pont and 3M) suppressed information about the harms of per- and polyfluoroalkyl substances (PFAS) for decades despite knowing how persistent they are in the environment and having copious evidence of the harms that they cause; in fact, when du Pont stopped producing (most) PFAS-containing materials (which were used for, among other things, lining food containers and wrappers) 3M actually set up their own manufacturing and is only now being forced to stop producing those themselves.
The claims that “there’s no evidence that [plasticizers and other chemicals that can leach out of plastics] dangerous” begs the question of how much research has been done to establish threshold limits and whether there is significant evidence of hazard that has not been made public by the companies whose profits depend on continued use of these materials. At one time, the public was told that lead was not a significant danger and it was put into products which included paint, dishware, plumbing, and even (in the form of tetraethyl lead) into ‘regular’ gasoline which basically created the largest incidence of heavy metal poisoning in human history. There is, in fact, significant evidence that phthalate esters (used in polyvinyl chlorate plastics) can contribute to heart disease and bisphenol is chemically nearly identical to several known endocrine disruptors. Nearly all plastics use solvents, flame retardants, UV stabilizers, alkylphenols and alkylphenol ethoxylates, biocides, metalloids, polycyclic aromatic hydrocarbons that are known carcinogens or acute toxins in quantity, and because of their persistence in the environment can accumulate in the body at concentrations potentially higher than what are considered tolerable levels.