Anything new on the dangers of microwave ovens?

Dear Cecil,
As far as microwave ovens go, I know I have heard about science experiments with giving plants the same filtered/ same temperature water, only one has been microwaved and one not. One plant is fine and microwave water is not. Is there any truth to this? And if so, since plants react so horribly with water that has been heated with a microwave, can that not logically suggest that it may be bad for humans as well? I know that there is much that humanity has to learn, isn’t it more prudent to take lessons from those less sensitive (i.e. canaries)? Just wondering if there is any realness to these claims, M. R. Gior.

The microwave water experiment apparently started with one girl’s science fair experiment. The girl supposedly watered one set of plants with water that hadn’t been heated in the microwave and another with water that had (and was allowed to cool). The results were very dramatic. The plants that were watered with microwaved water did very poorly. This got the attention of a lot of people.

The problem with this is that numerous people have tried to repeat the experiment and all of them failed to do so. In all subsequent experiments both sets of plants did equally fine.

Did the girl not allow the water to fully cool? Was there something else she did, possibly unintentionally, that caused the difference? This was just one girls’ science fair experiment. It’s not like it was done under rigorous scientific conditions in a controlled laboratory.

Snopes has an article on it here:

This case shows the problem with modern science as reported by the press and information passed around the net. The first result is shocking, so word of it gets passed around a lot. Subsequent tests don’t find anything, but “we didn’t find anything” isn’t interesting, so it doesn’t get reported. This leaves people with the impression that there’s something there when there really isn’t.

Microwave ovens, cell phones, and power lines all suffer from this. You’ll find a ton of information on the net about how dangerous all of these are. In real life though, rigorous studies and complete follow-up studies haven’t found anything bad.

Go ahead and microwave your water (and other things) all you want. It won’t hurt you.

Don’t put your penis in it.

The newest and latest research shows that microwaves continue to be perfectly safe.

It actually shows a problem with modern science. Positive results get reported in published papers. There is no funding to repeat someone else’s experiment and, if you do try and fail to repeat it, it is very hard to get the result published. Journals want positive results.

See how long it took Wakefield’s garbage to get withdrawn.

I haven’t tested this personally or seen any research on this, but I think it’s unhealthy to drop a microwave oven on one’s bare foot. Or a kitten or puppy either.

I’ve dropped a puppy on my bare foot - it was soft. The kitten tried to bite my toes.

So far only two experiments of this nature have been reported.

One was a done by a girl for a science fair project and used an experiment group with n=1 and a control group with N=1. It’s hard to draw any statistically significant conclusions from that.

The other was done by the folks at Snopes, and involved three groups of three identical plants, with one of each group subjected to a different watering condition (see engineer_comp_geek’s link). results were evaluted by “blinded” observers, i.e. observers who didn’t know which plants had received which type of water. They could not replicate the kid’s results. The number of plants involved is still pretty small - just three for each type of water - but that’s a good bit better than the kid’s science fair experiment.

Barring any further well-conducted experiments involving a much larger number of plants, it would be appropriate to assign a higher likelihood of accurate results to the Snopes experiment - that is, microwave ovens do not hazardously alter the properties of water (excepting that the resulting high temperature is a hazardous, albeit temporary, property). There is in fact no known mechanism by which they could possibly do so. Microwave radiation is composed of photons, each of which has relatively little energy compared even to visible light. No single microwave photon is capable of breaking a molecular bond (i.e. microwave radiation is non-ionizing), but if you throw enough microwave photons at a cup of water, the energy imparted will certainly heat it up.

I don’t mean to hijack the thread, but this condemnation of “modern science” is categorical bullshit and has to be called out. I’m particularly sensitive to it because this is the kind of argument that is so often used against controversial areas affecting public policy like climate science.

Putting Wakefield aside just for a moment, I can tell you with absolute certainty that the scientific literature thrives on the kinds of replications or refutations of results that you claim don’t exist; this is, in many ways, the very essence of science. What you’ve said is abject nonsense.

Now with respect to Wakefield, I don’t personally have a great deal of familiarity with the fraudulent paper on the MMR vaccine that I presume you’re referring to, but my understanding is quite different from what you’re implying. The paper itself only put forth the claim as an unproven hypothesis, which subsequent research did indeed significantly fail to replicate. The major problem wasn’t so much the paper as the outrageous grandstanding and public statements that Wakefield was making. No amount of contradictory research would have reversed this in the public’s mind; what it took was proof of vested interests and outright fraud on his part. Yet even today, thanks to lunatics like Jenny McCarthy and Michelle Bachmann, the idiocy persists – no doubt about it, but don’t blame science!

There’s also a secondary problem that is specific to the medical field. There are unique challenges particularly in the area of clinical trials, both in establishing normative boundaries of safety and in tracking the frustratingly capricious Kaplan-Meier curve in establishing the efficacy of things like cancer drugs. This is a realm in which claims of safety, efficacy, or lack thereof can linger for a long time even if false, and can even change over time. But again, these specific difficulties are not a basis for accosting the scientific method as dysfunctional.

There are times when it’s wise to err on the side of caution, but often it’s much wiser to approach these types of claims with healthy skepticism. Asking here if there’s a basis to this claim, as you’ve done, is a good step. Automatically assuming that if the claim is out there then one should give it some credence, not such a good step.

Agreed. The problem is not with science per se, but rather with the way some of its results are distorted and promulgated by popular media.

Myth Busters also tried it (three groups of plants: plain water, microwaved water, no water). The plants receiving microwaved water did just as well as the ones that got plain water.

This is purely anecdotal, but I can tell you I’ve been microwaving coffee for over 40 years and I’m still here to tell about it.

I believe that science can unequivocally state that canaries do better and sing more sweetly if they have not been microwaved.

Congrats on joining the Dope and may we see more posts from you soon, though the likelihood of that is even less than the chance of there being horrific undetected dangers of using microwave ovens.

40 years:eek: How is there any water/coffee left even after 10 minutes?:smiley:


I spend a lot of time reading the scientific literature, and only very rarely do I come across attempts (successful or otherwise) to directly replicate published results. (Indirect replications, in which a later experiment would not have produced meaningful results at all if the findings of an earlier one were not correct, are a bit more common.) The file drawer problem, whereby negative results are usually considered unpublishable, and so remain unreported, is a well known issue, much discussed amongst actual scientists. No-one thinks this invalidates science as a whole, or anything extreme like that, but it is a problem that needs (and, indeed, is getting) attention from the scientific community, but that remains difficult and problematic. The price of good science, like that of freedom, is eternal vigilance. Complacent myths about the wondrous, self-correcting nature of science, and the purity and inviolability of the “scientific method” do not serve it well.

Hari Seldon’s concerns are well founded, and certainly very far from being “abject nonsense”. You, by contrast, seem to me to be quite foolishly complacent, and your post appears to owe much more to a scientistic ideology than to any actual understanding of how science works in practice.

This might make an interesting GD thread if you folks are willing to take the conversation there.

Even if it were so, it’d only show microwaved water was bad for plants.

In all seriousness though, it does go to show the distrust people have when they don’t understand EM radiation. Or water.

OTOH, I stuck my little potted philodendron into my microwave oven and nuked it for a while, and it turned into a Godzillodendron and went into full rampage mode!!!

Sure I have a cite. I’m being semi-facetious here but really, has there ever been an important scientific theory that has achieved broad consensus on the basis of one single paper that was never challenged or corroborated? I don’t dispute the point you’re making, I simply say that it’s a very narrow one, most often seen in specific areas of medical research which has its own challenges as I’ve already said, and where there are vested interests anxious to see positive results in clinical trials.

But my original point was with regard to the big picture – the fact that significant claims like those of Wakefield were refuted – by the CDC, by the American Academy of Pediatrics, by the Institute of Medicine of the US National Academy of Sciences, by the UK National Health Service, and many others. So much for “negative results don’t get published”. Wakefield’s claim had traction only due to irresponsible and unwarranted public grandstanding and a grossly irresponsible popular media, some of which (like the notorious Daily Mail, currently doing right-wing hatchet jobs on climate science) were politically motivated.

My original point was also with regard to the ridiculous statement that “journals want positive results”. No, what journals want is meaningful research. Negative results are rarely as simple as “I tried what Joe did and it didn’t work for me”, which would be a very short and unpublishable paper. But in practice what does get published is usually a battle of competing theories, with negative results and other evidence forming the genesis of new hypotheses. It’s an opportunity to refine or entirely displace an existing theory based on new evidence. Indeed it’s been said that it’s the unexpected result, not the expected one, that leads to all real scientific advancement.

A discussion like this would belong in GD except that I’m not sure there’s really any more to say.