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Scientific American

Can You Hear Me Now?

published October 2010 | comments (22)
Physics shows that cell phones cannot cause cancer
magazine cover

Baseball legend Yogi Berra is said to have fretted, “I don’t want to make the wrong mistake.” As opposed to the right mistake? A mistake that is both wrong and right is the alleged connection between cell phone use and brain cancers. Reports of a link between the two have periodically surfaced ever since cell phones became common appendages to people’s heads in the 1990s. As recently as this past May 17, Time magazine reported that despite numerous studies finding no connection between cell phones and cancer, “a growing band of scientists are skeptical, suggesting that the evidence that does exist is enough to raise a warning for consumers — before mass harm is done.”

Their suggestion follows the precautionary principle, which holds that if something has any potential for great harm to a large number of people, then even in the absence of evidence of harm, the burden of proof is on the unworried to demonstrate that the danger is not real. The precautionary principle is a weak argument for two reasons: (1) it is difficult to prove a neg ative — that there is no effect; (2) it raises unnecessary public alarm and personal anxiety. Cell phones and cancer is a case study in the precautionary principle misapplied, because not only is there no epidemiological evidence of a causal connection, but physics shows that it is virtually impossible for cell phones to cause cancer.

The latest negative findings mentioned by Time come out of a $24-million research project published in the International Journal of Epidemiology (“Brain Tumour Risk in Relation to Mobile Telephone Use”). It encompassed more than 12,000 long-term regular cell phone users from 13 countries, about half of whom were brain cancer patients, which let researchers compare the two groups. The authors concluded: “Overall, no increase in risk of glioma or meningioma [the two most common types of brain tumors] was observed with use of mobile phones. There were suggestions of an increased risk of glioma at the highest exposure levels, but biases and error prevent a causal interpretation. The possible effects of longterm heavy use of mobile phones require further investigation.” This application of the precautionary principle is the wrong mistake to make. Cell phones cannot cause cancer, because they do not emit enough energy to break the molecular bonds inside cells. Some forms of electromagnetic radiation, such as x-rays, gamma rays and ultraviolet (UV) radiation, are energetic enough to break the bonds in key molecules such as DNA and thereby generate mutations that lead to cancer. Electromagnetic radiation in the form of infrared light, microwaves, television and radio signals, and AC power is too weak to break those bonds, so we don’t worry about radios, televisions, microwave ovens and power outlets causing cancer.

Where do cell phones fall on this spectrum? According to physicist Bernard Leikind in a technical article in Skeptic magazine (Vol. 15, No. 4), known carcinogens such as x-rays, gamma rays and UV rays have energies greater than 480 kilojoules per mole (kJ/mole), which is enough to break chemical bonds. Greenlight photons hold 240 kJ/mole of energy, which is enough to bend (but not break) the rhodopsin molecules in our retinas that trigger our photosensitive rod cells to fire. A cell phone generates radiation of less than 0.001 kJ/mole. That is 480,000 times weaker than UV rays and 240,000 times weaker than green light!

Even making the cell phone radiation more intense just means that there are more photons of that energy, not stronger photons. Cell phone photons cannot add up to become UV photons or have their effect any more than microwave or radio-wave photons can. In fact, if the bonds holding the key mole cules of life together could be broken at the energy levels of cell phones, there would be no life at all because the various natural sources of energy from the environment would prevent such bonds from ever forming in the first place.

Thus, although in principle it is difficult to prove a negative, in this case, one can say it is impossible for cell phones to hurt the brain — with the exception, of course, of hitting someone on the head with one. QED.

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22 Comments to “Can You Hear Me Now?”

  1. John Says:

    I just had to confront a cell phone “truther” with this as well as evidence from physics books, other publications and websites like, but did it convince her? Hell to the no! I should have known better. I even tried the Guy P. Harrison approach and looked for a common belief that we could work from and kept asking her what kind of evidence she would find acceptable and she wanted stuff like “live television broadcasting of scientific tests.” It was clear after fifteen minutes of wasted time that she was a scatterbrained true believer. Epic fail.

  2. Michael Kimble Says:

    Wouldn’t there be concern that just carrying the phone in your pocket would induce cancer in that part of the body it was next to also? Just because I’m not talking with the head set next to my ear doesn’t mean the phone isn’t still receiving data and signals broadcast to it, right? Doesn’t the phone have to be powered completely off not to receive any signals at all? If so, then logically, there should be higher incidences of cancer associated with parts of the body the phone rests against versus other parts of the body. I would also guess, as men are more likely to carry their phones in their pants pockets that men would have higher rates of this form of “cancer” than women? What about the hand holding the phone during the conversation? How is it that hands are magically immune from cell phone “radiation” but the brain isn’t? The people that believe this sort of thing seem to presuppose the uni-directional nature of radiation I guess. Unfortunately, once a persons mind has been made up, it is so very difficult to get them to change it.

  3. Katy Says:

    Michael, I’m not sure you really understood the meaning of the article. Although the author points out that a multitude of studies have shown no compelling connection between cell-phones and brain cancer, the point of the article is that cell-phones, according to what we know about physics, cannot cause any kind of cancer at all. The radiation a phone lets off, whether in your pocket, hand, or at your ear, is insufficient to break the bonds in of the DNA in cells, and therefore, cannot possibly cause cancer. No broken bonds, no mutations, no cancer.

    Furthermore, the author states that, “if the bonds holding the key molecules of life together could be broken at the energy levels of cell phones, there would be no life at all because the various natural sources of energy from the environment would prevent such bonds from ever forming in the first place.” Basically, if our everyday exposure to planet Earth doesn’t cause cancer, then cell-phones most definitely don’t cause cancer.

  4. Ken Hamer Says:

    I think the point he was making is that while some people seem to think holding the phone close to your head will cause cancer in the head (i.e. brain tumours) those same people have no compunction about holding the phone in their hands or leaving it in their pockets for hours on end.

    Appaently they think the cell phone emisssions hunt down brain cells to the exclusion of everything else.

  5. Edgar Jakubowski Says:

    I became scared when I realized that whole last night I had slept (8 hours) with my cell phone under my small and very thin pillow. If you can, please describe what in a future I may expect due to my negligence or stupidyty.

  6. Ned Coates Says:

    Edgar, You can expect an increasingly lumpier pillow.

  7. Steve Says:

    John, your truther was clearly an obsessive cell phone user.

  8. Michael Kimble Says:

    Ken, exactly my point.
    Katy, I should have been clearer in my post.

    Working as a computer consultant, you can bet I get this as well as the occasional wifi is going to kill us all and my monitor is irradiating me too. I especially love the crystals people hang on their electronics to help absorb radiation.

  9. Mike de Fleuriot Says:

    Hanging crystals over computer equipment, you have to be shitting me? Who allowed their parents to breed? I hate magic tricks, especially when they will not show how the tricks work.

  10. bill beaty Says:

    Misguided article, because experimental results determine theory, not the reverse. Multiple studies show that cellphones don’t cause cancer, and this demonstrates that the theory is almost certainly correct.

    But if multiple studies had turned up a large carcinogenic effect, it doesn’t mean that low frequency photons break DNA, or that Science comes to an end. It just means that the idea described by Shermer is wrong (or more likely, simply oversimplified.) We’d then go looking for the mechanism.

    The cellphone controversy is answered not by a characiture of what science is, but instead when we find that no, cellphones don’t actually increase our already significant cancer risk.

  11. Josef Firestone Says:

    The suggestive nature of the rumours that has been going around for the last decade are by themselves a cause of harm, furthermore the accumulated white noise and the total of communication tools is almost impossible to be correctly investigated. Maybe mobile phones by themselves are harmless but they just might contribute some.
    As far as the brain is concerned, how certain mental states plus the individual genetic situation combined is not properly understood.
    Anyway, “ÿour guess as as good as mine”.

  12. Richard Says:

    This article is a big mess, it is factually flawed and incorrect, and it has severe major errors that should have prevented publication. Hopefully it will be retracted soon, after the Editors will evaluate evidence that discredits most statements.

    Any environmental exposure can have 2 mechanisms of action: 1). direct, and 2). indirect. It is true that the energy of cell phone radiation cannot break DNA, the missing word in this article is *directly*. Thus, even the title is incorrect, “Physics” does not show that cell phones cannot cause cancer, it only shows that DNA breakage is not *direct*.

    So let’s forget about *direct* DNA breakage as being the only mechanism leading to cancer, that is immature, and non-scientific. Someone with a background in biology (not “skepticism”) knows better, I assume.

    What about the *indirect* effects of cell phone radiation? About 6 different research groups have independently shown that DNA breakage occurs after cell phone radiation, and among some of the mechanisms implicated are 1). generation of reactive oxygen species, 2). protein phosphorylation, 3). cell cycle perturbations, 4). protein expression changes, particularly that of Hsp70 heat shock proteins. Yes, they even know the mechanisms! Yay! The author desperately needs to sit down and read biology before “educating” his readership in biology.

    A huge flaw in this amateurish article, is that it assumes that breaking DNA is the only way to cause disease. This view is about 60 years backwards from our current scientific knowledge. It assumes that cells are made up of DNA and nothing else. Today, we know a lot about how proteins are affected in the cell, by environmental exposures, and we know specifically, in the case of cell phone-type radiation, that is has multiple ways in which it affects cellular proteins. This idea was already demonstrated by at least 15 different groups worldwide over the past few years only. There are already several articles published, showing protein changes in cells exposed to non-ionizing radiation, both in vitro and in vivo. Grow up, and get beyond DNA, learn some real biology!

    There is too much non-sense in this article, and the author really would serve his readership, as well as his own professional stature, if he would sit down and read about this topic before writing about it. Almost nothing in this article is true, most of the statements can be easily refuted with published facts, and it is a very amateurish piece of journalism that deviates very much from the known scientific facts that are published.

    Just do a Pubmed search and read the actual papers, none of which support the above piece. And by the way, a “negative” cannot be proven. Not in science. Perhaps in “public relations” or in “industry support sciences”, but that’s another story.

    So, as long as you present an article that abounds in factual errors, no, I cannot hear you, neither can any decent biologists who know more about the topic than you proved in this article.

  13. dmitriy Says:

    Please take a look at the attached article. This is a perfect example of crude simplicism offered under the uise of “scepticism”

  14. Clem Clone Says:

    But doofuses… you can’t cause cellular damage except by causing a chemical change (unless you want to consider mechanical damage, which I am sure you do not). Radio wavelengths are not energetic enough to do that, so they don’t — even if you want to use them for that. Shermer is not mentioning DNA as the sole target for potential damage, but rather as an example of a molecule that might be damaged — and every other molecular bond in a cell is exactly as radio-proof as those in DNA. ALL the world’s molecular bonds are radio-proof, because they are molecular bonds. Radio *equipment* would tend to break down if this were not so. (The Science Daily article appears to have no relevance to this other than the word “electrical”.)

    Why the hostility? Why so hot? Did Shermer once kick your pet puppies? Do you manufacture radiation-absorbing crystals? Here’s the deal: there is no evidence that radio devices cause any cancers (and angrily asserting that there is evidence doesn’t make it so — you have to cite specific publications. Relevant ones). But it seems like you’re intent on a creationist-style policy of deciding your favorite conclusions first, then cherry-picking facts that look supportive… if you look at them from the right angle… and not too closely.

    So if your great goal in life is to debunk the conspiracy of those who for some terrible reason want us to believe there is no cancer in cell phones, here’s what you should do: make that cancer happen. Take a bunch of rats and expose them to all the radio energy you can produce. It should be quite inexpensive to set this up, even if you go to the extra bother of a control group. Then, when you have an amazing number of rat cancers to tell us about, THEN you’ll be justified in mouthing off about amateurishness and who needs to grow up. Although it’d still be rude to do so, not to mention totally unnecessary, since anyone who operates in good faith is always interested in solid evidence — especially when it contradicts their existing model.

    So do that. You have nothing to lose, and everything to gain — not least the world’s gratitude. And if you do produce excess rat cancers — and no tricks, funny guys — then I will applaud you and be very interested. I bet Shermer will too. And that would mean you win! So DO THAT STUDY!

  15. Richard Says:

    Thanks for the suggestion, Clem Clone. The rat studies have been done, they are published, if you are so sure about your propaganda it means you did not do your homework and forgot to read the literature before opening your mouth.

    Moreover, if you had done your homework in public health, which is the focus of this topic, you would know that cancer is not the only concern but there are many biological modifications before cancer develops. Those, too, were shown to be caused by radio frequency and microwave radiation, not only in animal models but also in humans.

    So, do yourself a favor and read before you play the expert. You are wrong, and Shermer is totally wrong because he mislead the readership and did not read what he should have read, what any decent writer should have read, before writing an article on the topic. Shame on you for writing such junk and for distorting science and writing lies.

  16. LiveWires Says:

    Richard, save us all a lot of trouble – if you have these studies everyone *should have* read, please show us. I don’t take anything on faith, and you ask me to believe that you have special information and expertise that others do not, but have not produced this information.

    Help someone who wants to know – cite the studies you are referencing as required reading.

  17. Richard Says:

    Hello LiveWires,
    Thanks for your message. First, I don’t know who you are, I don’t recall talking to you before yet you mention “…you ask me to believe that…”.

    Anyway; try Levitt and Lai, Environ. Rev. 18:369:2010, and the references therein, this will help your background tremendously. It is an excellent review written by distinguished scholars, and the list of references will enrich your knowledge.


  18. Richard Says:


    Try also Salford et al., Environ Health Perspectives, 111(7):882:2003 and Persson et al., Wireless Networks, 3:1997:455.

    It seems that you and your adherents are not up to date with the literature on the topic, if you need to ask for references. Yet you all seem to be knowledgeable and wise enough to be dismissive and ignorant. Try also reading about European governments which advised citizens not to allow kids to use cell phones because they have established harmful effects on health. Yeah, they would not care much about the nonsense propagated by “skeptics” like you, in fact, you give a bad reputation to the word “skeptic”, because in your little world it becomes equivalent to ignorant. Too bad you don’t have the professionalism to read on this topic before you argue. You need to ask for references – that shows how prepared and professional you are. If I were you, I’d be ashamed.

  19. Nathan Krawitz Says:

    Why People Believe Weird Things. Read it. One of the points often brought up is that people will invent connections between new and unknown, and therefore misunderstood and feared new technology and the possible cause and effect of what is seen.

    Case in point: So many people were convinced that cell phones were causing fires at gas stations to the point that cell phone use was prohibited while fueling. With very true anecdotes showing fires starting while someone was on a cell phone, it is very easy to see a direct connection. Personally, I didn’t believe it until I read an article posted at a military gas station, although there was still doubt in my mind.

    Enter scientific method. Test the theory. The popular show Mythbusters explores many of these theories, although occasionally they don’t have adequate controls. But the spirit is always there, even to the point of seeing exactly what it takes to create the effect described.

    In one episode, the Mythbusters accurately delved into the cell phone gas station fires. No matter what they did, they couldn’t get a fire using a cell phone. Basically, only the gasoline fumes are flammable. The gasoline itself is too rich to burn, and dissipation of the fumes makes too little to burn. So you need a certain concentration of fumes, and also some way to ignite them. Cell phone energy is quoted, but even in receive? Or is it only when dialing? So some kind of spark is required.

    So if the Mythbusters couldn’t get a cell phone to cause a spark no matter what they tried, and there are well documented cases of gas station fires, then how does this happen? Well, a closer look at these fires show a few things. One, we don’t run our engines because the electrical elements in the engine could be the spark required. Likelihood is low but feasible, hence the law. Drive offs often start fires because the fuel nozzle is often still connected, then causes a spark when some metal part is dragged.

    So! We have a spark. But what about cell phones? Well, it seems that in some parts of the country, humidity is low often enough to note that one gets shocked when touching their vehicles. Mythbusters clearly showed the connection here! If anything, people were mindlessly speaking on their phones when entering or exiting their vehicles and blamed the phones.

    Now, most gas stations post that loose containers must be on the ground and no longer post cell phone warnings. Now if they can tell us to not enter or exit our vehicles while refueling.

    Does the statement pass the BS meter? Any of us can be caught believing something that seems plausible. We can also disbelieve things which are true. The test is being able to change our minds when better science is presented. If we stick to the principles of the scientific method, we will be able to objectively find out the truth. Maybe not today or tomorrow, but eventually.

  20. Richard Ozenbaugh Says:

    What is happening here? It seems that there is a lot of “credible” authors saying the contraty to thei article:

  21. Tom Says:

    Why does Skepticism have a bad reputation?

  22. DaftMuppet Says:

    I just saw on the news (CNN) that cell phones may be linked to cancer, so I quickly shared this article with my facebook friends. On the damned news! Insane.