What's the Straight Dope on Cell Phone Radiation?

[MattProle]

Recently, certain news outlets have been running segments on the potential risk of cellphone, claiming that prolonged exposure to cell phone radiation may cause some form of brain cancer. Here is one such story from CNN. However, despite mainstream media picking up interest, I remain somewhat skeptical of these accusations.

From the CNN link provided above:

In February, a study by researchers at the National Institutes of Health, revealed radiation emitted after just 50 minutes on a mobile phone increases the activity in brain cells. The effects of brain activity being artificially stimulated are still unknown.

This particular observation may be explained, perhaps, simply as a consequence of the brain lighting up (consuming glucose) due to the actual use of the cell phone (talking / the anticipation of talking). Of course, this nit pick depends on whether the appropriate controls were conducted for this experiment or not.
Looking at it from a mechanistic point of view, I feel somewhat confused. If I recall correctly, cell phones emit radiation in the form of radio waves, which may be seen along this graph of the electromagnetic spectrum. We see that radio waves are classified as the radiation with the longest wavelengths. Long wavelengths correspond to low frequency, and thus low energy (E = hv, v = c/L). Radio waves are so weak in comparison with ordinary radiation (visible / IR) that it seems hard to imagine a mechanism by which it could cause cancer. However, I’m no expert and I’m interested in what you Dopers have to say.

[Jragon]

From what I understand, cell phone radiation is “non-ionizing radiation” which simply cannot cause cancer by any means, in contrast to “ionizing radiation” most people think of when the generic word “radiation” is bandied about. However, I’m not an expert on the subject, it’s just what I’ve been told.

[Boyo_Jim]

The story is breaking today because a panel of “experts” (I don’t mean to disparage their expertise, but I don’t know what their expertise is) assembled by the World Health Association has just released a report saying cell phones may be carcinogenic. Specifically, a cancer called glioma. Story here.

They did not conduct a study. Instead they analyzed the results of many previous studies.

According to the story, a summary of their findings will be printed in the July 1 issue of The Lancet.

[Karen_Lingel]

Albert Einstein, in 1905, proved that cell phone radiation can’t cause cancer. He won the Nobel Prize for it in 1921.

Learn physics.

[Cat_Whisperer]

I wondered the same thing after hearing the same story on our local news, so I looked it up. Here’s a link to the National Cancer Institute discussing this topic from May, 2010. Bottom line - they’re pretty sure it doesn’t, but some studies have been inconclusive, and we don’t know the longterm effects yet.

ETA: They also say that limiting exposure and keeping the antenna as far away from your head as possible is not a bad idea.

[MattProle]

@Karen_Lingel

Albert Einstein, in 1905, proved that cell phone radiation can’t cause cancer. He won the Nobel Prize for it in 1921.

Learn physics.

I feel that my opening post has acknowledged this (albeit without an explicit cite). Still, there are persons of the medical community for which this is an apparently serious question. I don’t feel entitled to dismiss their anxieties just because it doesn’t jive with my understanding of physics.

If anyone has additional sources that definitively support or dismiss the notion that cell phone radiation causes cancer, please chime in.

[RaftPeople]

@Jragon

From what I understand, cell phone radiation is “non-ionizing radiation”…

Ok so far

…which simply cannot cause cancer by any means,…

I think you are overstating the case here, I think what you really wanted to say is that non-ionizing radiation can’t break the molecular bonds that ionizing radiation can break which is at least one way in which cancer is caused.

But I don’t think (I could be wrong) that anyone can say that the electromagnetic radiation couldn’t cause cancer in some other manner.

[Askance]

Mobile phone brain cancer warning disputed:

A global wireless industry group has disputed the significance of a report released by a UN health organisation citing a potential cancer link from use of mobile phones.

CTIA-The Wireless Association said the UN agency “conducts numerous reviews and in the past has given the same score to, for example, pickled vegetables and coffee”.

Also of interest: 3G phones less harmful, researcher says:

However, an Australian researcher who worked on the report with 30 other experts says more research is needed before any real link can be made between mobile phone use and cancer.

“Really, what it’s saying is there is an observed association between using a mobile phone and a higher risk of brain cancer,” Professor Bruce Armstrong from the University of Sydney told ABC on Wednesday morning.

“But it’s also saying that there are perhaps biases in the study or … other factors that could explain that association.”

Prof Armstrong said researchers studied radiowave activity on those who used phones the heaviest and for the longest period, and health risks for average users was “really quite small”.

“In the general population, particularly in the younger population,** there is just no evidence … that brain tumours are increasing in a way that would suggest that they are related to the greater amount of radio-frequency energy in our environment**,” he said.

The 3G technology used by iPhones, Blackberry and other mobile phones also appeared to emit less harmful radiowaves

[Shmendrik]

If radiation drops off rapidly with distance, and the EM radiation emitted by cellphones causes cancer, shouldn’t we see a much greater increase in skin cancer of the ear and cheek than brain cancer?

[just_some_guy5]

The study in question labels cellphone radiation as being “possibly carcinogenic”, which is the same risk category that’s been applied to coffee for some time. Doesn’t seem particularly alarming, but certainly worthy of an appearance in the 24-hour news cycle I suppose.

[MattProle]

I can’t recall who initially provided it, or in which forum, but this link has answers much of my questions:

Cell Phones and Cancer Risk Fact Sheet

Here is a small portion from the link:

Additional studies have investigated the risk of developing glioma, meningioma, and acoustic neuroma. Results from the majority of these studies have found no association between hand-held cell phone use and the risk of brain cancer (6–11); however, some, but not all, studies have suggested slightly increased risks for certain types of brain tumors (12, 13).

Another study is also cited:

In addition, pooled analyses of data from four Nordic countries and the United Kingdom did not show overall associations between the risk of glioma or meningioma and the cumulative hours of cell phone use or the number of calls (19, 20). There was a slightly increased risk of glioma occurring on the same side of the head as the reported phone use among persons who used a cell phone for at least 10 years (19).

Yet another study, except a different method was used for data acquisition:

In an attempt to avoid the issue of biases associated with case-control studies, researchers defined a cohort of 420,095 persons in Denmark with cell phone subscriptions and linked this roster with the Danish Cancer Registry to identify brain tumors occurring in this population (10, 11). Cell phone use was not associated with glioma, meningioma, or acoustic neuroma, even among persons who had been subscribers for 10 or more years. Cell phone service subscription does not necessarily relate directly to cell phone use, duration, and frequency of use. A listed subscriber may not be the primary user of the phone. However, this type of prospective study has the advantage of not having to rely on people’s ability to remember past cell phone use.

It appears that many of the purported small positive correlations between incidence of glioma and extent of cell phone use can be explained simply as a function of some minor hidden bias in the studies.

sigh

That’s the last time I take a sensational claim made on the news too seriously.

[MattProle]

@Cat_Whisperer

I wondered the same thing after hearing the same story on our local news, so I looked it up. Here’s a link to the National Cancer Institute discussing this topic from May, 2010. Bottom line - they’re pretty sure it doesn’t, but some studies have been inconclusive, and we don’t know the longterm effects yet.

ETA: They also say that limiting exposure and keeping the antenna as far away from your head as possible is not a bad idea.

Ah that’s where I found the link. Thank you Cat Whisperer!

[KarlGauss]

This thread opened after I had posted in the ‘testicular cancer’ thread. Because it’s of even more relevance here, I hope it’s not considered too egregious if I re-post what I said there:

@KarlGauss from the testicular cancer vis cell phone thread

@KarlGauss

As I understand it, the WHO conclusion (linked above) was based on a single study which concluded there was an association (and there were 30 studies showing no such association).

And, what about that single (and unfortunately influential) study? It was based on people’s recall, i.e. “now that you’ve had a brain tumor diagnosed, think back; did you use a cellphone in the past? how much”?

Such studies are next to useless and very often come up with spurious associations. One that comes to mind had to do with multiple sclerosis and dogs. People with MS were asked if they ever had a dog and, if so, did the dog have neurological troubles like seizures. Well, of course people with MS would be more likely to remember that type of thing given they themselves now had neurological problems (they may have had years to reflect on “why did this happen to me? what was I exposed to?”). But, if you’re well, it may slip your mind that Fido once shook all over for five minutes. And even if you do remember it, you may not consider it as being anything significant. If you have MS, you recall it as a seizure. Subsequently, prospective studies showed no association between MS, owning dogs, and/or your dog having neurological problems.

In other words, the recent labeling of cell phones as a possible cancer hazard was based on one study of highly questionable methodology (and at odds with the 30 negative studies). No doubt it is because ‘cancer’ is such a loaded diagnosis, that any link to it, even when tenuous and based on weak data, is given more weight than it deserves.

[Boyo_Jim]

@KarlGauss

This thread opened after I had posted in the ‘testicular cancer’ thread. Because it’s of even more relevance here, I hope it’s not considered too egregious if I re-post what I said there:
In other words, the recent labeling of cell phones as a possible cancer hazard was based on one study of highly questionable methodology (and at odds with the 30 negative studies). No doubt it is because ‘cancer’ is such a loaded diagnosis, that any link to it, even when tenuous and based on weak data, is given more weight than it deserves.

Thanks, I will cease storing my cell phone in my anus. The gerbil needs more space anyway.

[Captain_Amazing]

@Boyo_Jim

Thanks, I will cease storing my cell phone in my anus. The gerbil needs more space anyway.

Not to mention that he uses up all your roaming minutes.

[user_hostile]

NPR did a story 15-18 years ago on what is called “stochastic resonance”. It was hypothesized at the time that this could be a possible physical mechanism for inducing cancer. The idea being that in spite of cell phone radiation being non-ionizing, the resonance created by the microwaves could create enough energy to induce a mutation in the cell. Since then, however, I’ve heard nothing about it. Anyone else heard this story?

[Jackmannii]

Good analysis of the state of knowledge regarding cellphone “cancer risk” here.

Bottom line: Recent research has been trending strongly away from the conclusion that cellphones cause cancer, and rather than concluding that such an association is “possible”, the WHO had far better reason to conclude that it is extremely implausible.

[Gyrate]

Cellphones are carcinogenic, but only if you eat them.

[CookingWithGas]

MIchael Shermer, who writes the Skeptic column for Scientific American, says, “Cell phones cannot cause cancer, because they do not emit enough energy to break the molecular bonds inside cells.”

[RaftPeople]

@CookingWithGas

MIchael Shermer, who writes the Skeptic column for Scientific American, says, “Cell phones cannot cause cancer, because they do not emit enough energy to break the molecular bonds inside cells.”

Saying “cell phones cannot cause cancer” because 1 potential method is eliminated is not very logical.

Cancer can be caused by anything that increases the rate of mitosis. Can Michael Shermer say that cell phone usage does not increase the rate of mitosis for any cells, period?
Just to be clear: I’m not arguing that cell phones do or do not cause cancer. What I am arguing is that it is incorrect to state that because cell phone radiation is non-ionizing, that all avenues of it causing cancer have been eliminated.

Furthermore, given the recent study showing increased metabolism in brain cells near a cell phone that was turned on - it would seem that the energy from a cell phone is enough to influence biological activity. If this increased metabolism increased the rate of mitosis, then you have a possible avenue for causing cancer.