How Dangerous Is Cell Phone Radiation?

Popular stories and Internet videos say that cell phone signals are dangerous. Is there any truth to this?

by Brian Dunning

Filed under Consumer Ripoffs, General Science, Health

Skeptoid #117
September 2, 2008
Podcast transcript | Listen | Subscribe
Also available in Spanish | Russian

Cell Phone Radiation
Artwork: Nathan Bebb

Today we're going to pick up virtually any consumer magazine or open any Internet news web site and read about a frightening new threat: That radiation from cell phones is dangerous, perhaps causing brain tumors or other cancers, maybe even cooking your brain like an egg or like popcorn. Most people have no knowledge of science other than what they hear on the news, so we have a whole population growing up with this understanding. Is the fear justified? Do cell phones have the potential to cause physical harm, or are they completely safe? Or, like so many other questions, is the truth somewhere in the middle?

Let's take a closer look at exactly what kind of threat is being reported. A recent article on quotes Dr. Debra Davis, Director of the University of Pittsburgh's Center for Environmental Oncology, saying that "You're just roasting your bone marrow" and asking "Do you really want to play Russian roulette with your head?" The article goes on to give five recommendations for limiting your exposure to cell phone radiation: Using a headset, using the speakerphone, getting a different phone, and so on. CNN followed up with another article with more quotes from Dr. Davis, this time saying that children are especially at risk because their brains are still developing, so they should be allowed to use cell phones in emergencies only.

As the director of an oncology center, she must have all kinds of experience treating cancer patients, and since she's going on CNN to talk about cell phone risks she must have a lot of experience dealing with cancer caused by cell phones. Right? Well, you'd think, but apparently CNN is not quite that particular about their guests. Dr. Davis' Ph.D. is in "science studies", whatever that is, and she is neither a medical doctor nor does she have any specialization in physical sciences like radiation. Now, I'm not trying to disrespect Dr. Davis — she has a fine background loaded with experience and all sorts of publications and accolades in her field — but I do want to draw attention to the fact that when CNN brings a doctor onto television to talk about a health problem, you shouldn't take anything for granted. You're the one who assumed that she treats cancer patients and has seen harmful effects from cell phone radiation. The fact is that the only danger Dr. Davis actually cited was that "since cell phones have only been in widespread use for 10 years or so, the long-term effects of their radiation waves on the brain has yet to be determined." Neither she, nor CNN, cited a single case of harm being caused by a cell phone, nor did they present any theoretical arguments indicating any plausible danger.

Dr. Davis is also dramatically wrong on one very significant point: That there has not yet been time for long-term studies to have been conducted, or that the question of cell phones and cancer is otherwise inadequately studied. In fact, the Journal of the National Cancer Institute published the results of a massive study in Denmark that followed the cancer histories of 420,000 cell phone users over 13 years. You'd think that someone in Dr. Davis' position would know about that, or at least take the slightest trouble to search for studies before going on CNN to proclaim that no such studies exist. The study's main interest was to search for increased incidences of brain or nervous system cancers, salivary gland cancer, and leukemia. The study concluded:

Risk for these cancers ... did not vary by duration of cellular telephone use, time since first subscription, age at first subscription, or type of cellular telephone (analogue or digital). Analysis of brain and nervous system tumors showed no statistically significant [standardized incidence ratios] for any subtype or anatomic location. The results of this investigation ... do not support the hypothesis of an association between use of these telephones and tumors of the brain or salivary gland, leukemia, or other cancers.

The lack of any connection is not surprising, given that no plausible hypothesis exists for how a cell phone could cause tissue damage. RF below the visible spectrum, which includes the frequencies used by cell phones and all radio devices, is not ionizing radiation and so has no potential to damage living cells or break any chemical bonds. Microwave ovens, which operate just above cell phones on the frequency scale, work by oscillating such an extremely powerful field back and forth, causing the water molecules to rub against each other and create heat by friction. Cell phone signals are three orders of magnitude weaker, too weak to move the water molecules, and do not oscillate to cause friction. Scratch the heat hypothesis, scratch the ionizing radiation hypothesis, and there are no plausible alternatives. Of course it's not possible to prove that there is no potential for harm, but all sources of harm known or theorized to date are clearly excluded.

So if that's true, how did the story get started? How did cell phones causing cancer become one of our pop culture myths?

It started in 1993, when a guy named David Raynard went on CNN's Larry King Live to talk about his lawsuit against the cellular phone industry over the death of his wife from brain cancer, who used a cell phone. Certainly we all sympathize with Mr. Raynard, but that doesn't make him right. Unfortunately for rationalism, being on Larry King was all the credibility the story needed to become a popular belief. Despite Mr. Raynard's claim that his wife's tumor was in the same shape as the cell phone antenna, the case was thrown out for a lack of evidence.

Another reason the belief persists is that it is constantly being promoted by companies selling quack devices claimed to protect consumers from any potential threat. Spreading fear is a major marketing angle that they employ. Cardo Systems, a maker of cell phone headset, broadly promoted as the best way to minimize danger of radiation, famously released a set of hoax videos on YouTube showing people popping popcorn by setting some kernels on a table between several activated cell phones. When nailed for the hoax by CNN, Cardo's CEO claimed that the videos were meant only as a joke and that the thought of scaring people into thinking that cell phones could pop popcorn never entered their minds. You can judge the credibility of that statement for yourself.

There are also a number of videos on YouTube showing eggs being hard boiled merely by placing them between two activated cell phones for a few minutes. This claim has also been thoroughly debunked. The British TV show Brainiac even tried it with 100 phones. The result? Zippo. It didn't change the egg's temperature at all. Raw as ever.

Some of these companies selling products to protect you have sections on their web sites where they cite official statements reiterating that there is no proof that cell phones are safe. They also tend to cite one particular study, known as the Guy study and published in Bioelectromagnetics in 1992. You might remember Guy's co-author C.K. Chou, an RF scientist who did some research we examined in our episode about The Hum. The Guy study exposed rats to high levels of RF for 22 hours a day for two years. 18 of the exposed rats developed tumors, while only 5 of the control group did. The cell phone accessory companies stop there, but you have to dig deeper to find that other researchers have been unable to replicate these results, and the conclusion was that the tumor incidence, while statistically significant, was not shown to have been caused by the RF. In fact, another study also published in Bioelectromagnetics by Adey et. al. exposed rats to a chemical carcinogen and then exposed some of them to RF. Dr. Adey actually found fewer tumors in the RF exposed rats, but again the result was not large enough to draw conclusions. Even in the harshest of animal studies, no evidence has been found to link cell phone radiation to health problems.

We may quarrel with these companies' ethics in promoting fear to sell their products, but that doesn't mean that the products aren't a wise precaution. It can't hurt to be safe rather than sorry, can it? Well, you will be sorry if you spend any of your hard-earned money on a product intended to protect you from cell phone radiation, and you hear what the World Health Organization has to say on the matter. Their summary on such devices says:

Tip Skeptoid $2/mo $5/mo $10/mo One time

Scientific evidence does not indicate any need for RF-absorbing covers or other "absorbing devices" on mobile phones. They cannot be justified on health grounds and the effectiveness of many such devices in reducing RF exposure is unproven.

So far, the science that's been done pretty much supports the default skeptical position. When we hear a claim like "cell phone radiation causes cancer", we assume the null hypothesis until evidence is presented that supports the claim. And to date, all the good evidence supports the null hypothesis, not the claim. Maybe tomorrow things will change, and we'll find that cell phones are harmful, or that 60-cycle electrical outlets are harmful, or that traveling faster than 30 miles an hour is harmful. An open skeptical mind is open to any good evidence supporting any claim. But for now, I'm going to continue enjoying the usefulness of my iPhone, and be damn glad there's a tower in my neighborhood.

Brian Dunning

© 2008 Skeptoid Media Copyright information

References & Further Reading

Cohen, E. "5 tips to limit your cell phone risk." Cable News Network, 31 Jul. 2008. Web. 13 Jan. 2010. <>

Johansen, C., Boice Jr., J., McLaughlin, J., Olsen, J. "Cellular Telephones and Cancer: A Nationwide Cohort Study in Denmark." Journal of the National Cancer Institute. 7 Feb. 2001, Vol 93, No 3: 203-207.

Muscat, J., Hinsvark, M., Malkin, M. "Mobile Telephones and Rates of Brain Cancer." Neuroepidemiology. 3 Jul. 2006, Vol 27, Issue 1: 55-56.

Shermer, M. "Can You Hear Me Now? The Truth about Cell Phones and Cancer: Physics shows that cell phones cannot cause cancer." Scientific American. 4 Oct. 2010, Volume 303, Number 4: 98.

Tahvanainen, K., Niño, J., Halonen, P., Kuusela, T., Alanko, T., Laitinen, T., Länsimies, E., Hietanen, M., Lindholm, H. "Effects of cellular phone use on ear canal temperature measured by NTC thermistors." Clinical Physiology & Functional Imaging. 1 May 2007, Vol 27 No 3: 162-172.

WHO. "Electromagnetic fields and public health: mobile telephones and their base stations." World Health Organization. World Health Organization, 1 Jun. 2000. Web. 13 Jan. 2010. <>

Wilson, J. "What to know before buying your kid a cell phone." Technology. Cable News Network, 11 Aug. 2008. Web. 13 Jan. 2010. <>

Reference this article:
Dunning, B. "How Dangerous Is Cell Phone Radiation?" Skeptoid Podcast. Skeptoid Media, 2 Sep 2008. Web. 30 Aug 2015. <>


10 most recent comments | Show all 131 comments

I am not so quick to dismiss this as a POSSIBILITY.

We have learned over the last 30 years that humans are effected by all forms of radiation, sound frequencies, and even sunlight.

How it effects us is only cut and dry in a very LIMITED amount (example x-rays level of lethal harm).

The rest is effected by a large amount of variables and in no small part by the factor of TIME.

A good example of this variance is not everyone who sunbathes gets a lethal skin cancer.

In fact alot of people in earlier times due to atmospheric conditions (the theory of the ozone layer for example) were less effected than now.

Or the fact that a specific radiation may not DIRECTLY CAUSE it but over time change subtlly DNA or damage something that makes us more vunerable to another cancer that unless you know THE EXACT HISTORY you would never know (or know for sure) that (ex) cell phone was the contributing cause.

But brian and others would be foolish to dismiss the possibility that cell phones COULD BE a cause or aid illness.

Remember a simple search of what "experts with studies over years" just about the FDA alone shows the folly of doubt

Eric, Northern IL usa
July 23, 2013 1:18am

After reading a few of your posts on this subject, I'm exceedingly disturbed by your arguments and the way you have constructed them. For those who know nothing about this field of inquiry, they may appear to hang together. But for people who, unlike yourself, have been studying this area more deeply,from a biological perspective, and over a long period of time, your selection of talking points is frighteningly biased, with cherry-picked phrases, and could not be based on an independent inquiry on your part. Even if you had weak investigative skills, you could not have landed on the items you brought up--and distorted-- without stumbling on a large body of peer-reviewed information to the contrary. This array of "facts" could only have been prepared for you by an interested party, like the wireless industry or someone whose wealth is dependent on this bias. It comes glaringly right out of the industry playbook. You are putting yourself out as the go-to person for the straight story, and then misleading the public in exchange for ... what? Money? Pats on the back? What? You clearly are uninformed at best, and purposely misinforming the public at worst.

My advice to anyone reading these "episodes" is that they look up every piece of information included independently. You will see that you have been misled. Do not be any less skeptical of a "skeptic" website than you would be of any other site.

M Glaser, Chicago
November 12, 2013 9:21am

skeptic website

marianela, new mexico
March 27, 2014 10:25am

There is a dramatic increase in reported incidences of Breast Cancer among young women. This is verifiably true through the Journal of the AMA:

"In the United States, the incidence of breast cancer with distant involvement at diagnosis increased in 25- to 39-year-old women from 1.53 (95% CI, 1.01 to 2.21) per 100 000 in 1976 to 2.90 (95% CI, 2.31 to 3.59) per 100 000 in 2009. This is an absolute difference of 1.37 per 100 000, representing an average compounded increase of 2.07% per year (95% CI, 1.57% to 2.58%; P < .001) over the 34-year interval"


Now what is responsible for that increase is still unknown. You have to start identifying lifestyle factors that have changed over the last 25 years. Increasing cell phone use, and the trend to carry it inside the bra, has risen.

I don't think there is any definitive link, but along with unhealthy eating choices, the rise of ingested synthetic hormones, lack of exercise, and environmental radiation are all things that should be investigated.

Cancer is rising, and we need to find out why in order to save lives.

BillyJoeJimBob, ThisPlanetEarth
April 12, 2014 1:00pm

Strange that you would attribute the 1.37-per-100,000 increase to cell phones. Why not the rise of organic food? The authors make one suggestion, attributing it possibly to the increase in diagnostic sensitivity.

Brian Dunning, Laguna Niguel, CA
April 12, 2014 2:04pm

How about living in an apartment where
there is a cell phone tower on top?

from a personal survey among friends
who live in apartments with cell towers
there seemed to be a correlation.

maybe that is the study needed.

also the denmark study was long ago before
the full market penetration of cell phones,
should need a follow up...

mreateg, lima
December 7, 2014 10:34am

How was the above posted? Cover those wifi modems with Al Foil!

Mulga Gill, Sydney
July 7, 2015 6:23pm

@M Glaser, Chicago: Would you care to name any specific claims that you think Brian got wrong?

Josh, Spokane, WA
July 30, 2015 3:36pm

Yesterday the NY Times published an article about this subject. The NY Times article itself was worthless because they didn't even name the study, but I wrote to the author and she gave me the study itself.

I don't have time right now to go through it. Would anyone else who has more time care to go through it and see if it has anything of merit in it (or, alternatively, expose its flaws)?



Josh, Spokane, WA
July 30, 2015 3:40pm

^Sorry, I horrendously mistyped. NY Daily News, not NY Times.

Josh, Spokane, WA
July 30, 2015 3:40pm

Make a comment about this episode of Skeptoid (please try to keep it brief & to the point).

Post a reply


What's the most important thing about Skeptoid?

Support Skeptoid

Captain Kidd's Treasure
Skeptoid #481, Aug 25 2015
Read | Listen (12:07)
The Nazi of Nanking
Skeptoid #480, Aug 18 2015
Read | Listen (13:49)
Skeptoid #479, Aug 11 2015
Read | Listen (14:28)
Listener Feedback: Natural History
Skeptoid #478, Aug 4 2015
Read | Listen (11:36)
Wag the Dogman
Skeptoid #477, Jul 28 2015
Read | Listen (13:03)
#1 -
Read | Listen
#2 -
Harry Houdini and Sir Arthur Conan Doyle
Read | Listen
#3 -
The Death of Rasputin
Read | Listen
#4 -
The Water Woo of Masaru Emoto
Read | Listen
#5 -
The St. Clair Triangle UFO
Read | Listen
#6 -
Tube Amplifiers
Read | Listen
#7 -
The Braxton County Monster
Read | Listen
#8 -
Read | Listen

Recent Comments...

[Valid RSS]

  Skeptoid PodcastSkeptoid on Facebook   Skeptoid on Twitter   Brian Dunning on Google+   Skeptoid on Stitcher   Skeptoid RSS

Members Portal


Follow @BrianDunning

Tweets about "skeptoid"

Support Skeptoid

Email: [Why do we need this?]To reduce spam, we email new faces a confirmation link you must click before your comment will appear.
characters left. Abusive posts and spam will be deleted.