Cell Phone Radiation Affects Brain, Study Says

Extended use of a cellular telephone causes increased activity in parts of the brain next to the phone's antenna, according to a new study in the Journal of the American Medical Association. However, Nora Volkow, author of the paper, says it's unclear what the clinical significance of that finding is.

Copyright © 2011 NPR. For personal, noncommercial use only. See Terms of Use. For other uses, prior permission required.

IRA FLATOW, host:

This is SCIENCE FRIDAY. I'm Ira Flatow.

There has been much talk about whether cell phones may have some deleterious effect on our brains from the radio waves coming out of the antenna being held right up against your head.

Well, studies have gone back and forth on whether or not cell phone use could be a health risk, with most in the industry saying that it has no proven ill effects.

Just this week, a study published in the journal Bioelectromagnetics reported no statistically significant change in the incidence of brain cancers in men and women in England between 1998 and 2007, a time when cell phone use increased dramatically.

But now, new work published this week in the Journal of the American Medical Association says there is an identifiable effect of cell phone use in the brain, but it's really too early to tell what, if anything, that effect means health-wise.

Joining me now to talk about it is Nora Volkow. She's director of the National Institute on Drug Abuse at the NIH and one of the authors of the JAMA paper. Welcome back to SCIENCE FRIDAY.

Dr. NORA VOLKOW (Director, National Institute on Drug Abuse, National Institutes of Health): Thanks for having me here. How are you?

FLATOW: How are you?

Dr. VOLKOW: I'm good, and you?

FLATOW: I'm fine. Can you tell us what actually was seen happening in the brain?

Dr. VOLKOW: Well, the story goes on to try to answer that question: Is the human brain sensitive or not to the weak electromagnetic radiation that is delivered from cell phones when you place them by the side of your ear? And we use positron emission tomography to measure brain glucose metabolism, which serves as an indicator of brain function because when the brain is activated, glucose metabolism goes up.

And what we found was when we compared images of the brain when subjects had their cell phones, the right cell phone activated versus when they had the cell phones inactivated, there was a significant increase in brain glucose metabolism in the area of the brain near the antenna; which indicates that, indeed, the human brain is sensitive to the electromagnetic radiation emitted from cell phones.

FLATOW: So you've seen the glucose activity, meaning something is happening, but you don't know what is happening.

Dr. VOLKOW: Right. We don't know where - first of all, we do not know what is the mechanism that is leading to the increase in glucose consumption, glucose metabolism. We interpret it to mean that the brain is activated because that's what happens when cells are activated: They increase the consumption of glucose.

But how is that brought about? There's been a lot of controversy, for example, of whether cell phones could increase the temperature of the brain, which in turn could affect energy requirements. Alternatively, others have said: Could it be that you are changing the electrical gradients across the membrane that make cells much more excitable, or whether you are disrupting blood-brain barrier.

The mechanism, we do not know, and also, the other issue that we don't know, which is the one that has generated the most interest, is how those things relate, for example, to the question of whether cell phones have or don't have potential deleterious effects to the brain.

And based on our study, which documents that it's sensitive, we really cannot infer whether this is a bad or could even have potentially good applications. So that - our finding does not illuminate or enlighten that very important question of whether cell phone exposure could have detrimental effects.

What it does tell, I mean, in being - in looking at the data in my brain certainly, is that we do have the obligation to evaluate whether there are long-term consequences from this exposure to electromagnetic radiation or not. But we need to evaluate it in such a way as to be able to answer this question.

FLATOW: 1-800-989-8255 is our number. We're talking with Dr. Nora Volkow of the National Institutes of Health. You can also tweet us, @scifri, @-S-C-I-F-R-I. And Dr. Volkow, it's interesting that you say - I hear you saying we need to have now further studies to find out what's going on there.

Dr. VOLKOW: Yes, indeed, and I think that we need to - to me, the most important one, and that's the one that we as a research team would like to pursue, is what are the consequences of repeated stimulation of this type into the brain, say after 10, 15 years. Are there long-lasting changes? Or is this just an acute effect that if one's cell-phone exposure is interrupted, it has no consequences at all. And there are no answers for that particular question. We do not know.

FLATOW: How long - just in your study, how long was the cell phone - did people have the cell phone up to the ears?

Dr. VOLKOW: Fifty minutes.

FLATOW: Fifty, 5-0 minutes.

Dr. VOLKOW: Five, zero, 50.

FLATOW: Five-zero minutes, and did the effect go away immediately when the cell phone was removed?

Dr. VOLKOW: Well, we didn't' study that because the way that we conducted the study, we only get one measurement. So the measurement was being done the last - so the cell phone was activated 30 minutes before we injected a radioactive glucose, and then it was continued for 20 minutes.

So what we actually saw in terms of brain glucose metabolism were the effects of having the cell phone stimulating your brain. But it would be, of course, very interesting to evaluate, say, for example, 10 or 15 minutes. Does metabolism goes back to its previous state, or does it stay activated for a longer period of time?

Unfortunately, our study cannot answer that question.

FLATOW: But you're saying those are the kinds of studies that need to be, now, started.

Dr. VOLKOW: Absolutely, and, too, I mean, even if it's safe, for example, I put my cell phone, and I get activated for two or three hours after this discontinues. Suppose I'm fantasizing that that's what happens because I don't know if it does or if it doesn't.

But the issue that, to me, is interesting, but the most important question, is: Does it start to change the way that the brain functions in ways that it does not recover? That is to me the question that would worry me, if there is a long-lasting effect that persists after the exposure has long gone, in ways that could be detrimental to the function of the brain.

And that, there is no data to indicate that that is the case, but also there is no data to indicate towards that we have evidence that that's not going to happen. And those studies should be done.

FLATOW: How would you do that? What would the protocol be like? Would you follow the same people, or do you just do sort of a population-wide study?

Dr. VOLKOW: It's a very difficult study to do, and I think that in your question, you're already hinting at that. First of all, you're not going to be able to do a randomized trial, which is the way - the idea, experimental protocol to address if there are differences between metabolism in subjects that you're following prospectively that are exposed versus those that are not. That is a very unrealistic study.

Nonetheless, within the constrains that one has, certainly you would like to, for example, ideally be able to do a prospective study that follows individuals at one point in time, in terms, for example, of brain glucose metabolism or activation patterns, using all their technologies, and then you follow them and assess if the areas of the brain, which are the ones that receiving the highest amount of electromagnetic radiation and do show the changes versus a control area that's far away.

And this is actually possible for two things. One of them is we all tend to use our cell phones, in general, on the same side of the head. And we all tend to use it as to place the upper part in our ear and the lower part towards our mouth.

So based on the cell phone model that you're using, you can very much estimate where the antenna is located and which are the areas that are going to be affected. One could take that difference, for example, of laterality and of placement within the brain in a prospective design.

It's not trivial because cell phone technology changes, and one of the things, for example, that in the meantime, people say: Well, how are you using this information to give recommendations to others? Is it of any value?

And I said, well, it obviously will depend on the degree of uncertainty that you are willing to take. I'm very conservative with uncertainty on my brain, but that's my own neurosis.

(Soundbite of laughter)

Dr. VOLKOW: So I - as a result of this, I do use an earpiece that I attach to the cell phone, or I use the speaker phone. And this, to me, is such a trivial solution. So I said, well, why not? It allows me to keep on using my cell phone, and at the same time, it deals with my neurosis of being unable to really tolerate the notion that there could be any deleterious action. But I'm neurotic.

FLATOW: Yeah, well, we all are. And you get - let me just think outside the box for a second with you here, if you'll indulge me. Let's say you had a device, it's not a cell phone, you had a device, and you were a company that made medical devices.

And you had a device that you put up to someone's ear, and it stimulated some change in the brain, and you can show that there was a change in the brain. And you wanted to market this device. Wouldn't you have to prove to the FDA or whoever it is, Consumer Products Safety Division, that whatever device was creating this change in your brain had to be safe before you could market it?

Dr. VOLKOW: Yes. You have to prove that the device is not going to cause damage to your patients, just like you do also, of course, for medication. The issue that becomes more problematic is you design trials to try to address that question within a certain period of time.

So, say, for example, that I do have a device and I think that if there is evidence that this weak electromagnetic radiation does not have any untoward effects, I think, it is a valid question to try to do research to determine if there are potential therapeutic applications.

But - so if I do a study and I do - I follow my subjects, say, for example, for 12 months or 24 months, does that really answer the question properly? And it's maybe that if not until I have followed them for five or 10 years...

FLATOW: Right.

Dr. VOLKOW: ...as the brain becomes also older, because what you may not see in a young brain that has much more resilience may become much more sensitive as an individual becomes older and has a cumulative effect from the exposure to that particular device.

FLATOW: I guess what I'm asking is if you have discovered that there's a device that affects the functioning of your brain and we don't know how that effect really is over the long term, isn't it up to the people who make the device because it does affect our brain like it would be any other medical device to first prove before they can sell it to me that it doesn't have any deleterious effect?

Dr. VOLKOW: But right now someone that is in the manufacturing company could come to you and say prove to me that there's any harmful effects of cell phones. The cell phone technology has exploded, and there's really no clear-cut evidence of any harmful effects. And if there were harmful effects, because there are so many people exposed to it, it would have already become evident.

FLATOW: Yeah.

Dr. VOLKOW: So when you - you know, in that paradigm where you can never completely rule out one way or the other all - and again, this issue has been going back and forth with respect to whether cell phone exposures are safe or not, to me, and that's why I come - reiterate our finding in no way clarifies that whole controversial issue because activation of the brain in and of itself is not something negative. It's physiological. I am activating several areas of my brain. You want me to activate them because otherwise I wouldn't be functioning properly.

I'm thinking what I'm going to tell you and so my whole frontal cortex is probably using glucose metabolism. The areas of the brain, the auditory cortex are using glucose metabolism. So this - and probably increasing metabolism as much or perhaps even more in some instances to where we observe with the cell phone stimulation.

The difference is that it's a physiological activation as opposed to what you see with a cell phone exposure. And we don't know - I mean, we really literally do not know if this is in any way negative at all or not.

FLATOW: Let me just remind everybody that this is SCIENCE FRIDAY. I'm Ira Flatow. This is SCIENCE FRIDAY on NPR. Talking with Dr. Nora Volkow.

Sorry, Doctor, to interrupt. Go ahead. You were...

Dr. VOLKOW: No problem. No, no. And - but I'm also listening very clearly to your question of should manufacturers of technology not prove to us that they are safe. And again, this also depends of what are the threshold of safety and what are the regulations.

FLATOW: Yeah.

Dr. VOLKOW: And I think that this is going to - as a society, may force us to view what is it that's going to be acceptable in terms of risks for technology and what's unacceptable. Because let's take a car. I mean, cars kill. It's the number one cause of deaths among young people. Great technology, there are clear cut risks, and yet, we accept them.

So I think the issue here that is different is we don't understand. We don't really know that sense that this is a type of energy that we've - we have not properly investigated with respect to consequences on the brain or perhaps even other tissues of our body.

FLATOW: And who should do the investigation? Should it be the cell phone companies? Or should it be the federal government? Your division doing that investigating?

Dr. VOLKOW: Well - again - and I too - I mean, if you are running a company and you have to basically get sufficient revenue in order to survive, you have to make decisions of what you're going to do in order to minimize - to maximize your profits and minimize your risks. And you do realize that you want to have a safe product because that - otherwise, that could kill you.

So it's like anything else, making a balance, and that's where also the government has played an extraordinary important role in providing the infrastructure to address research questions that pertain to the health of all of us.

So I don't know that one could come up with a recipe of who should be responsible. Ultimately, I think both the companies and as well as the governments are responsible to provide with knowledge and information that can allow individuals to make decisions about what is healthy and what they should try to avoid.

FLATOW: Hmm. As I said before, if you want to create a medical product or a drug or a product or something don't you have to prove that it's safe before you can sell it? Don't you?

Dr. VOLKOW: Correct. And that's something that we're always - and that you can have a medication. They proved that it's safe within, say, a trial that's done over two or three years later. And then, they found 10 years later that when they look back, there a much greater incidence of stroke. But stroke being such, in this case, a low frequency, you are not able to detect it during the first two, three years.

FLATOW: Hmm.

Dr. VOLKOW: So that's where you also see that it's not foolproof. I think that it's a system that helps, but we have to recognize also that there are limitations.

FLATOW: Hmm. And so you come down on saying you're very conservative. I'm going to be wearing my Bluetooth instead of my cell phone on my ear.

Dr. VOLKOW: I'm not saying Bluetooth. I'm saying...

FLATOW: Oh.

Dr. VOLKOW: ...a (unintelligible)...

FLATOW: Do we know that Bluetooth is any better?

Dr. VOLKOW: I don't know. I don't know. That's why I don't know...

(Soundbite of laughter)

Ms. POLS: ...and I'm using one of these wire earpieces.

FLATOW: So should we put a Bluetooth in the PET scanner?

(Soundbite of laughter)

Dr. VOLKOW: Well, I think that that is an important question. It depends which next questions you want to answer.

FLATOW: So let's go with that one first. I've got about a minute before the break. We'll continue it. But should we - since you put the cell phone in there, now, should we try a Bluetooth and see what happens?

Dr. VOLKOW: We could do the Bluetooth or we could do the questions you asked me. Well, once you interrupt the cell phone, how long does it take the brain to go back to normal? So which question do you think I want to jump into?

FLATOW: I don't know which one you want. I know that I think I'd like them all answered.

Dr. VOLKOW: Me too. I do want them all, but I don't have all of the time of the world so I have to make a decision of which one we're going to go next.

FLATOW: And you have to decide what kind of money we can spend on that.

Dr. VOLKOW: That's absolutely correct...

FLATOW: All right.

Dr. VOLKOW: ...by all means.

FLATOW: So can you stay with us a few more minutes?

Dr. VOLKOW: Yes.

FLATOW: All right. We're talking with Dr. Nora Volkow, who is working over there very hard to figure out where the cell phones - what they're doing in our brains. She's the head of the National Institute on Drug Abuse at the NIH.

1-800-989-8255. We'll take some of your calls. You can tweet us @scifri, @-S-C-I-F-R-I. Maybe, you know, you want to not hook up that cell phone directly to your head and use an earpiece, a wired one like Dr. Volkow is talking about, instead of a Bluetooth, which she's - I guess, she's not convinced of quite yet either. We'll ask more after the break, so stay with us. We'll be right back.

(Soundbite of music)

FLATOW: You're listening to SCIENCE FRIDAY. I'm Ira Flatow. We're talking with Dr. Nora Volkow. She's director of the National Institute on Drug Abuse at the NIH.

One question for you and then we'll get one from our audience. Why is the drug abuse division of NIH looking at cell phones?

Dr. VOLKOW: Well, I - you know, I'm an investigator, I mean, a part. And so I've been studying the effects of drugs in the human brain for all of my professional career. And one of the technologies that we use in order to do so is magnetic resonance imaging. And magnetic resonance imaging, of course, relies on very potent magnets, stationary, as well as fluctuating magnets.

And I've been interested specifically to the question: Do these magnetic fields affect the function of the brain? So I - is the instrument that we're using by itself affecting brain function in the technology we're trying to extract information directly about brain function?

So for the past 15 years, we've been investigating the effects of magnetic radiation and exposure into brain metabolic activity. And we've shown - this was a recent study - that when we did place the subjects in the magnet and we use that gradient coils which are shifting gradient back - magnetic fields back and forth, we produce a significant change in brain glucose metabolism.

And so when we had those results, immediately the question that emerge is if that is the case, could there also be an effect from exposure to the electromagnetic radiation from cell phones?

So we came at it very indirectly by trying to understand whether the tools that we were using to study the human brain by themselves could affect functional signals. And we did document that magnetic - shifts in magnetic fields can produce evidently by producing electrical gradients and electrical currents in the brain, which after all cells communicate with one another by passing electrical currents. Because we showed that it could affect brain glucose metabolism, then that led to that question, well, what about...

FLATOW: Right.

Dr. VOLKOW: ...cell phones?

FLATOW: Well, it looks like you took the initiative on this thing. So where would you go next?

Dr. VOLKOW: Well, I'll - I mean, now, I mean, I'm starting from substance abuse disorders trying to understand how they affect the brain, and now, I'm faced with this finding which always happens when you do research. You start with one question, and you end up with many more questions.

But of the questions that I'm most interested is trying to figure out if there is a design that we can do realistically that - realistically, I mean, that we'll not be incredibly expensive - that can address that very important question: Are there long-lasting consequences from exposure to these weak signals of electromagnetic radiation? I'd like to be able to answer that question in a way that it's comprehensive and provides information that is useful.

FLATOW: Well, we welcome your results, Dr. Volkow, when you finish that study.

Dr. VOLKOW: Yeah, me too. And I - it's not simple. Experimentally, as I say...

FLATOW: Yeah.

Dr. VOLKOW: ...it's going to be...

FLATOW: Well, maybe you should get the cell phone companies to pitch in with you here?

Dr. VOLKOW: No. It will be conflict of interest.

FLATOW: Yeah. Well, the drug companies always study their drugs, right?

Dr. VOLKOW: I - they do, but it's also very unclear. That has generated a lot of controversy of whether a study that is funded by a company that's producing that drug is as credible as one that is not funded by them but is completely independent.

FLATOW: I hear you. I hear you. Well, we'll be rooting for you.

Dr. VOLKOW: Very well. Thanks very much.

FLATOW: All right. Thank you very much, Dr. Volkow.

Dr. VOLKOW: Thanks for having me. Bye-bye.

FLATOW: You're welcome. Dr. Nora Volkow is director of the National Institute on Drug Abuse at the NIH, and we'll see how far she can get in finding out how persistent those changes in the brain are.

Copyright © 2011 NPR. All rights reserved. No quotes from the materials contained herein may be used in any media without attribution to NPR. This transcript is provided for personal, noncommercial use only, pursuant to our Terms of Use. Any other use requires NPR's prior permission. Visit our permissions page for further information.

NPR transcripts are created on a rush deadline by a contractor for NPR, and accuracy and availability may vary. This text may not be in its final form and may be updated or revised in the future. Please be aware that the authoritative record of NPR's programming is the audio.

Comments

 

Please keep your community civil. All comments must follow the NPR.org Community rules and terms of use, and will be moderated prior to posting. NPR reserves the right to use the comments we receive, in whole or in part, and to use the commenter's name and location, in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.