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CNN Larry King Live

Study Looks at Possible Cell Phone Cancer Link

Aired May 17, 2010 - 21:00   ET

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

(BEGIN VIDEOTAPE)

LARRY KING, HOST (voice-over): Tonight, do cell phones cause cancer? A just-released study has some answered about brain tumors and other life-or-death health risks. So put down your cell a minute and pay attention.

The debate over cell phone safety rages on right here next on LARRY KING LIVE.

(END VIDEOTAPE)

KING: Well, the long-awaited international study of whether there is a link between cell phone use and an increased risk of brain cancer is finally being released. Conclusions of this decade-long, 13-nation interphone study will be published tomorrow in the "International Journal of Epidemiology."

With us from France is Daniel Krewski. Dr. Krewski was a participant in the interphone study. He's professor and director of the R. Samuel McLaughlin Center for Population Health Risk Assessment at the University of Ottawa.

Daniel, I understand the study was funded in part by the cell phone industry. Doesn't that raise some questions?

DANIEL KREWSKI, PARTICIPATED IN CELL PHONE STUDY: Well, people often ask that, Larry. And it is true that part of the funding did come from the cell phone industry. But it was set up in such a way that there was absolutely no involvement of the industry in the conduct of the study or the interpretation of the study results.

What we did is we engaged a new national scientific body, the UICC, the Union International Control of Cancer, to basically serve as a fire wall. The industry funding came to the UICC.

They in turn worked with the World Health Organization who led the study and there was no contact between the industry and the study participants or the investigators throughout the entire 10-year period of the study. And one of the --

KING: What --

KREWSKI: -- terms of the agreement that we had --

KING: I'm sorry, go ahead. KREWSKI: One of the agreements that we had -- one of the agreements that we made with the industry as part of that support is that they would not see the study results until they had been peer reviewed or accepted for publication, and finally that publication is scheduled to appear tomorrow in the "International Journal of Epidemiology."

KING: All right. The key question, what should the cell phone user take away from this study?

KREWSKI: Well, I think there's some very important bottom lines if we want to look at what the study has shown. First, with this very large study, as you mentioned, involving 13 countries around the world, taking place over a period of almost a decade, 10,000 individuals in all 13 countries are interviewed with respect to their cell phone use and formed the basis for the study conclusions.

Overall, the study showed no increased risk of the two types of brain cancer that we focused on, glioma and meningioma. So I think that provides us some assurance that we don't have an epidemic of brain cancer associated with general patterns of cell phone use in the general population.

Second major finding was that amongst the highest users of cell phones, long-term heavy users in the study -- the top 10 percent of cell phone users -- we did see a possible increase in the risk of glioma. About a 40 percent increase over background levels.

But the international study team that reviewed the results was not convinced that that necessarily is a clear finding because many of those individuals reported implausibly high values of cell phone use and we also have to take into account the possibility of different sources of air, re-caller (ph) and selection bias.

Bottom line is that the international study group saw that as a suspicious result but not clearly direct evidence of an increase in risk.

KING: Forty percent sounds pretty high to me. But why was the United States not included?

KREWSKI: The United States was initially part of the planning group. We go all the way back to 1998-'99 when we conducted a two-year feasibility study in several of the countries that were involved to ensure that we had enough experience with cell phone use to make the study worthwhile, to ensure that we design it in such a way to detect a small risk should in fact there'd be risk.

The United States was a part of that original planning team. But outside the European Union, countries had to secure their own funding nationally to be a participant in the study.

Canada was able to secure funding through federal granting agencies. Unfortunately that, was not the case in the U.S.

KING: How did the study define heavy use? KREWSKI: Heavy use was a -- well, if you were a participant in the study, Larry, what we do is we'd ask you to sit down and talk to us about your past cell phone use. We'd ask you to try and recall every cell phone, make and model, that you'd ever used throughout your entire lifetime.

We then ask you how many calls did you make on a typical day. How long were you on the phone. And we used this as a major of your cell phone utilization.

One of the measures of exposure that we used in addition to number of calls and average call time was the cumulative amount of time that you were on the phone during the course of the study period.

And a heavy user was defined as an individual who made more than 1640 hours of cell phone calls during the course of the study.

KING: And then did you say what percentage of them developed a brain illness?

KREWSKI: The relative risk in that high -- heavy user group was about 40 percent higher than the background risk of brain cancer. You'll see most of the risk estimates in our publication are expressed in terms of relative risk.

So you'll see a number of 1.4 means the risk in the cell phone user group relative to the non-cell phone user group is 40 percent higher than the background brain cancer rate.

KING: Would you say if you don't have to use your cell phone, don't use it?

KREWSKI: Well, if I looked at the interphone study itself, the two main conclusions that we've already talked about are first that overall we're not seeing an increase risk in the entire study population.

Second, there is this hint of an increased risk in the long-term heavy users of a possible increase in glioma risk but not strong enough evidence that the group is willing to conclude that there's a causal association there.

So we can ask the question, what does this mean for individuals who are using cell phones?

And if we look at the interphone study in conjunction with the literally thousands of papers that have been written on radio frequency fields and health, separately from interphone, look at the entire body of evidence, most experts groups who have reviewed this evidence have not concluded that we have compelling scientific information to establish a link between cell phone use and cancer risk.

KING: All right.

KREWSKI: But at the same time, there are these suggestions of a risk. And if you are concerned as an individual, you might want to take a personal risk management decision to try and reduce your risk.

And there are several ways you can do that. One is you could use a headset. The radio frequency field strength is strongest near the tip of the antenna in the phone. And if you keep the phone away from the head and neck area, you're not exposing the brain to the RF fields.

You could also use a Bluetooth earpiece which is much lowered power than a conventional cell phone. Many jurisdictions around the world are regulating that you have to use a hands-free unit, particularly in automobiles, which is going to, again, keep the field strength away from the head and neck area.

And you can choose to use your cell phone a little less. So in my view, it's -- if you are concerned, I think it's a personal decision to take some measures to reduce your exposure.

KING: There's another side to this story. Dr. Krewski will remain us with. Others will join us next.

(COMMERCIAL BREAK)

KING: Daniel Krewski remains with us. The report released -- will be released tomorrow. We're joined by Dr. Ronald Herberman, chairman of the board, Environmental Health Trust, and chief medical officer of Intrexon Corporation, founding director of the University of Pittsburgh Cancer Institute -- excuse me -- a long pedigree here -- for cancer research.

And Devra Lee Davis, founder, Environmental Health Trust and professor of preventative medicine, Mount Sinai Medical Center, author of the forthcoming book, "Disconnect: The Truth about Cell Phone Radiation."

All right, Dr. Herberman, what do you make of this study?

DR. RONALD HERBERMAN, CHAIRMAN, ENVIRONMENTAL HEALTH TRUST: Well, in a way I'm not too surprised because the study was delayed for almost five years from the time it was completed.

And several of the countries -- I believe it was six or seven -- published their own independent component of the study. So the overall conclusions are not that much different than what one saw from the aggregate of the separate countries that had published some time ago.

KING: Deborah, does it add to your concern?

DEVRA LEE DAVIS, FOUNDER, ENVIRONMENTAL HEALTH TRUST: Well, it certainly does but --

KING: Or not?

DAVIS: It certainly does add to my concerns because you see, as Dr. Herberman just indicated, there were a number of studies published from these individual countries and they all found one thing -- any time they were able to look at people who would use cell phone for 10 years or more -- and there aren't many of those studies that do that. But every single study that is able to look at people who use a cell phone for 10 years or more finds a risk of brain cancer that is almost doubled or greater. So I don't take much comfort in those findings because we don't have that many studies of people who used a cell phone for 10 years heavily.

KING: Daniel, how do you respond?

KREWSKI: We considered that issue at the outset when we designed the interphone study back in the late 1990s. We went through a two-year feasibility phase to determine whether or not we had enough experience with (INAUDIBLE) technology to make the study worth while.

We thought that if there was a risk it would be small and we would need a large number of subjects which is why we went to an international study involving 13 countries and over 10,000 subjects.

And by and large, I think we designed the best possible study that would address the potential cancer risk of cell phone use based on use patterns that occur during the study period.

DAVIS: I would agree with that.

KING: Ronald -- hold it, hold it, hold, it, Devra. Ronald, it seems to me that main concern here is the heavy user, the 40 percent increase in the very heavy user. Is that your main concern?

HERBERMAN: My main concern are twofold. One is the heavy user and the other is the long-term user. I'm also particularly concerned about young adults and children who are not part of the interphone study. Because there is lots of reasons to believe that the younger age-group will be more vulnerable and at risk for this.

This is mainly based on another epidemiologic study by Leonard Hardel from Sweden who studied teenagers who began to use cell phones during their teen years and they were followed for at least 10 years.

And in that group, rather than a 40 percent increase, he observed a 400 percent increase, four times the amount of brain tumors in that group compared to the control subjects.

KING: Devra, I understand you brought a model of a brain to give us a brief demonstration of why you're concerned about cell phone use and brain cancer. You have it there?

DAVIS: I do. Let me show you two of them, actually. This is a brain sitting in the skull. And you -- I want to point out to you that the interphone study did not look at tumors of the hearing nerve, did not look at tumors of the cheek.

In fact, I published an analysis with researchers at the University of Pittsburgh that found that for people who use cell phones heavily for 10 years or more, they have a 50 percent greater risk of tumors of the hearing nerve.

Now the most troubling thing, as Ron just told you, has to do with exposure into a child's brain. You see here the amount of radio frequency absorption into a child's head. And you have to understand that the current model that we use for cell phones are based on those of an adult.

This is the adult brain. This brain model here was developed by Professor Ogandi in research originally done for the cell phone industry. And the cell phone industry's own studies confirm that a child's brain will absorb a lot more radiation than will an adult.

So what we can conclude from this is that we have to protect our children. We know that their brains are more sensitive. They grow threefold in the first year of life. And they continue to develop throughout life.

In fact, they don't get fully mature until the 20s. And as a consequence, we are really conducting an experiment now. The interphone study studied no children, no teenagers. It studied people between the ages of 30 and 59 who used phones from 1990 to 1994 and analyzed the brain tumors in them in 2000 to 2004.

The average user in that study used a cell phone two hours a month. Many people are using a cell phone today two hours in a single day.

KING: I got to take a break. We'll come back. We'll be right back. Dr. Otis Brawley of the American Cancer Society will join us as well. Don't go away.

(COMMERCIAL BREAK)

KING: Joining us now -- joining the panel is from Atlanta, Dr. . Otis Brawley, chief medical officer of the American Cancer Society, a practicing oncologist and, like all the other members of the panel, wants to be called by his first name.

All right, Otis. You're the oncologist. What is your reaction?

DR. OTIS BRAWLEY, CHIEF MEDICAL OFFICER, AMERICAN CANCER SOCIETY: Well, first, as an oncologist and an epidemiologist, let me congratulate Dr. Krewski. He's done a wonderful study. He's done a very traditional analysis. I agree with his analysis. I agree with his explanations including his caveats.

An important thing to realize about medicine and about science is you cannot prove that something does not exist. I can't do a study to prove that cell phones are completely safe and do not cause cancer. I can only do a study and say I've looked very hard and I can't find evidence that cell phones cause cancer.

I don't want to trivialize those who think the cell phones are dangerous. I think that this study should give us a little bit of, shall we say, comfort? But we still need to do additional studies.

We need to see what the effects of cell phones are after 10 years, 15 years, 20 years. And the important question, what about young children?

KING: Ronald? How do you react to what Otis just said?

HERBERMAN: Well, I think the point about the length of time is really critical. If we look at most of the things that we know -- causality of causing human cancer -- ionizing radiation, asbestos, the list goes on and on -- you would not have found it in this type of study where you were looking at people mainly with exposure that was relatively small and for a short period of time.

That's why it's so important to look at the studies that have been done looking at people, using cell phones fairly frequently every day for a period of over 10 years. And virtually all studies that have looked at that particular issue have come up with the same finding that in that situation, there is an increased risk.

It may be 40 percent. It may be 100 percent, it may be a bit more than 100 percent. But a journal of ours as oncologists, "The Journal of Clinical Oncology." published a meta-analysis (ph) looking at all of these studies last year and it was a clear finding that for the long term use, there is something to be concerned about.

KING: Help me, Devra. Are we saying don't use your cell phone unless it's urgent emergencies? Is that what you're saying?

DAVIS: We're saying how you use your cell phone is important. If you use your cell phone with an earpiece or a speaker phone, then you are safer. But learning that right now cell phones are very powerful devices. They're driving economic development in Africa and China.

Nobody's going to stop using them. We need to use them in a safer fashion. And children --

KING: Right.

DAVIS: -- should not use them except for emergencies. Held up to the brain is the issue, Larry.

KING: Daniel, would you agree with that? Use it with the earphones and limit children excessively?

KREWSKI: I think it's wise to be careful, particularly if you have personal concerns about the use of this technology. But a number of groups have looked at outstanding research needs including the U.S. National Research Council about a year and a half ago and every group that's looked at what we don't know keeps pointing to one thing.

We need more information on children's use of cellular telephones. And that need is going to be met by a new study that is just beginning in Europe called MOBI-KIDS. Roughly speaking, it will be interphone but designed for the pediatric population.

KING: Dr. Brawley, are you encouraged by the fact that text messages are on the increase?

BRAWLEY: Yes, I am encouraged about the use of text messages. I would say that I'm a little bit more comfortable in using my cell phone than perhaps Dr. Davis would be. But I would also say that anyone who's concerned about cell phones and concerned that they might cause tumors, just use a wired earpiece or perhaps a Bluetooth.

KING: We'll take a break, come back, we'll ask our guests how much time they spend with their cell phones. Next.

(COMMERCIAL BREAK)

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KING: Iconic figure, doesn't do a lot of interviews. One of our top requests of all time has finally made.

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KING: We'll have a sneak peeks of our interview with Mick Jagger. Go to the CNN.com/Larryking. That's tomorrow night, full hour with Mick Jagger.

Back with our panel. Let's get to some quick questions we'll cover with each.

Dr. Krewski, is it harmful if it's on all day but it's in your breast pocket?

KREWSKI: I don't think we have any epidemiologic evidence that relates directly to cardiovascular events that you might think of. So I really don't think I have any scientific information to offer on that, Larry. Perhaps the other panelists do.

KING: Does anyone -- Dr. Brawley, are we harmed when it's not being used but it's in our pocket?

BRAWLEY: No, I don't think it's been studied.

KING: A number of countries, Devra, including Israel, France, Finland and the UK, have issued warnings about cell phone use. Should the government -- our government -- do the same?

DAVIS: Well, it's a good question, Larry. Because why did our government not participate in this study when it was started in 2000? I really would like to know that. I think that we need to figure out what's going on that the European Environment Agency issued a warning to the Environmental Health Trust conference in Washington, D.C. that the Finnish Nuclear Radiation Agency has advised its citizens to be careful in using cell phones.

And about your question about the breast pocket, if you read in fine print in the cell phone manuals, it says, of course you don't keep a cell phone near -- in your breast pocket if you have a Pacemaker. That then raises questions about what if you don't have a Pacemaker? And most people don't realize where is the antenna of a cell phone? It's in the back of the cell phone. You don't ever want to keep the phone on with the antenna facing into your body.

KING: Daniel, how do you respond to what she just said?

KREWSKI: Well, there are some studies, actually, looking at whether or not your cell phone would interfere with the operation of a cardiac Pacemaker. And I think there is a small risk of such interference. So that is a legitimate concern.

KING: Ronald, the FCC uses a specific absorption rate, which measures the amount of radio frequency absorbed by the body, to determine if a cell phone is deemed safe. Is this the right metric for measuring?

HERBERMAN: Well, I think it's on right track. But if you look at the details of it, it underestimates the amount of RF that's given, because it's based on a model of a very large man. And for smaller people, there is more radiation being delivered, as Devra showed with the model.

I'd also come back to the issue about keeping the device in a pocket. Probably the most striking evidence for me that it can cause some damage is a study that was done at the Cleveland Clinic and at a couple of other institutions that if you keep the cell phone in your pants pocket, a man, this has been shown to cause a significant decrease in sperm counts. And that is an indication that this can have biological effects that can be damaging.

KING: All right, wow. That's scary enough. All right, for each of the guests, just quickly -- Daniel, how often do you use a cell phone every day?

KREWSKI: I use my cell phone primarily for businesses -- business purposes, Larry. I would guess I'm probably using my phone somewhere between 30 and 60 minutes per day.

KING: Ottis?

BRAWLEY: More like an hour to an hour and a half. Part of it by head set, part with the phone up to my head, part of it with the Blue Tooth in a car.

KING: Ronald?

HERBERMAN: It varies from day today. But it's somewhere between 30 minutes and two hours. But I always use it either with a head set like this, or the speaker mode. And I think that is the prudent thing that I actually advice to my staff when I was a director of the University of Pittsburgh Cancer Institute.

I actually don't agree with Dr. Krewski to say that this is something that people should decide for themselves. I think there should be experts who know about the data and have reviewed it and to provide advice. Otherwise, the public gets hopelessly confused about the stories. Yes, no, maybe. And I think that the precautionary principle is something that is very important and should be adhered to.

KING: I'll have Daniel respond. But Devra, how often do you use it?

DAVIS: I use my cell phone between a half hour to two hours a day. I never use it without an earpiece or a Speakerphone. Whenever possible, I use a land line. And, Larry, many people today don't even have land lines. That is a big problem, because they're using the cell phone much more. They're not aware of the precaution that many professionals are taking. I certainly don't want my grandchildren using a cell phone now.

KING: And the pay phone has disappeared. Daniel, you want to respond to what Ronald said?

KREWSKI: Well, I'm sympathetic to the use of precautionary principle where science is perhaps somewhat uncertain. What I'm not clear on is how we can actually implement the precautionary principle in some kind of regulatory environment.

KING: Let me get a call in from Toronto, Canada. Hello.

CALLER: Hi, two questions just quickly. Should we be concerned about cordless phones in the house? I know we're talking cell phones. But do cordless phones not work off of a similar system? And, secondly, we're not allowed to use now our -- in Toronto, we're not allowed to use our cell phones driving. We do. So I'm using the speaker part sitting on my lap. Is that safe? Or safer?

KING: Devra?

DAVIS: Obviously, you don't want to keep a phone on your lap for a number of reasons, one of which is you can be distracted while driving and then have an accident. There, unfortunately, have been cases of that. It's best to have the phone away from the body. It doesn't have to be much more than this away from the body. That's important.

KING: Do we need more studies?

DAVIS: But on to cordless phones, he also asked. Excuse me, Larry. Cordless phones are a problem. And that -- and they were not included in the interphone study. The interphone study excluded anybody that used a head set, and it didn't ask whether people had cordless phones in their homes. And cordless phones can have as much exposure, if not more than a cell phone, because the base station of the phone is on all the time. That's why Doctor Herberman advised people to use a land line in their own homes.

KING: Ottis, do we need more studies?

BRAWLEY: We absolutely need more studies. The caller from Canada brings up a very important point. If you take the data from Dr. Heartwel (ph) who has published most of the data that shows that cell phones are harmful, by the way, and you apply it to the United States, we're talking 200 to 300 additional brain tumors per year. I don't want to trivialize that at all. But with data that shows that cell phones cost 3,000 to 4,000 automobile deaths per year. So we need to deal with both of these issues.

KING: Thank you all very much. We have not heard the last of this. And what ever happened to the pay phone? Remember the thing on the street? It was handy.

We're going to meet a woman who claims her husband's heavy cell phone use caused his malignant brain tumor. That's next.

(COMMERCIAL BREAK)

KING: Ellen Marks joins us from San Francisco. Her husband Allen has a malignant brain assume. She, as well as some medical and scientific experts, believe the tumor is associated with Allen's long-term heavy cell phone usage. She has testified before Congress about the risks posed by cell phones. How do you know this? How do you know it was cell phones?

ELLIE MARKS, HUSBAND HAS MALIGNANT BRAIN TUMOR: Hi, Larry. Thanks for having me. How do we know? Allen used a cell phone to his right ear for over 20 years. It's called ipsolateral (ph) use. After his diagnosis, his seizure, grandmal (ph) seizure, and diagnosis, the night of May 6, 2008 -- he had a craniotomy shortly there after. The same week Senator Kennedy was diagnosed -- I think maybe a week or ten days later -- with -- he had a grandmal seizure and was diagnosed with a glioma also.

Our son had interned for Senator Kennedy. Several months later, after the fires were out, my son came to me and said, mom, they were both on their cell phones all the time. I started researching this extensively. I've gotten to know Devra quite well. I know Ron. I testified with Ron Herberman to Congress in September of 2008.

What I did was I gathered Allen's cell phone records, his medical records, and I sent them to experts around the world. I found so much information on the Internet, I could hardly believe what I was reading. And I was terrified for the rest of us, especially for our children and grandchildren. And the experts got back to me and they said, yes, it definitely looks like Allen's glioma, which is the major -- what I know that the Interphone Study has focused on -- is a direct -- is a result of his long-term cell phone use.

KING: That study said, in large, people who use a lot, there's a 40 percent chance of getting that cancer. So do you agree with the study?

MARKS: I agree, yes. You're speaking about the Interphone Study now, correct?

KING: Yeah.

MARKS: There have been many fine studies.

KING: The one going to be released tomorrow.

MARKS: Right. Exactly. And the Interphone Study, what I have heard today -- or the last couple of days -- is that they have shown that people who use them for -- I think they only studied people between one and four years -- who use them for about 1,640 hours, lifetime hours, that there is a significant increased risk of brain cancer. My husband and many others -- mind you, after I went to Congress -- and we've been on "The Dr. Oz Show" and we've been on national newscasts -- mind you, many people -- I have a list of probably about 1,000 at home who have contacted me, who are either dead or dying from this and there they're as young as 28.

So my husband used it for 1.2 hours daily for 20 years. And I absolutely agree that this is a huge problem. And I'm not going to tiptoe around this.

KING: Yeah. Do you use one?

MARKS: Yes, I do. I do not believe in abandoning the technology. I equate it to automobiles. When we realized -- you know, when there were more accidents, we added air bags. We added seat belts. I do not believe that somebody should be taking their own precautions with cell phone use. I don't think that if you told somebody to get in the car now, and you didn't tell them that they had to use a seat belt, that that would be used.

These things are killing people. This has destroyed my familiarly. It has destroyed thousands of people's lives. Brain tumors are insidious disease that destroy entire families. The government needs to warn us. Go ahead.

KING: How is Allen doing?

MARKS: Allen is -- he's struggling. He's a valiant warrior, but he's struggling. It's a lot harder for him. He had a craniotomy. He has a large cavity in his head filled with scar tissue. It is malignant. He doesn't know when -- he doesn't know when it will come back. We definitely know that it will. And it's a horrible thing to have to live with. He had severe personality changes from it. He's had cognitive issues from it.

It's a horrible, horrible disease. And unfortunately I can tell you so many stories about so many other people, much younger than him.

KING: We're running close on time. I can promise you we're going to do a lot more on this. And we'll have you back frequently.

MARKS: OK. I appreciate that. One thing I would like to say --

KING: We're out of time.

MARKS: Thank you.

KING: We'll have you back, I promise.

MARKS: OK.

KING: "LARRY KING LIVE" contacted cell phone services providers. We contacted AT&T, Verizon, Sprint, Nextel and T Mobile, as well as phone manufacturers Nokia, Samsung, LG Electronics, Sony Eriksson, RIM, Apple and Motorola. These companies, which responded -- those companies which responded to our request for a statement or a spokesperson said they would let CTIA, the wireless association, speak on all their behalf.

A statement issued by John Wall, CTIA's vice president of public affairs, says in part "Interphone's conclusion of no overall increased risk of brain cancer is consistent with conclusions reached in an already large body of scientific research on the subject. All cell phones sold in the United States must comply with the FCC's radio frequency exposure standards, which are designed to include a substantial margin of safety for consumers. Numerous experts and government health and safety organizations around the world have reviewed the existing data base of studies and on going research and concluded that RF products meeting established guidelines pose no known health risk."

Tonight's 25th "LARRY KING LIVE" moment is next.

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MICK JAGGER, SINGER: You are already held in low regard in most countries. If you even step out of it, ever, what people want you to be is a little band that plays in clubs and that's where you should belong. You know? They don't want you to be a big success. You're never the same. So especially in England, in those days, and even now, I think that you -- if -- once you become a success, a worldwide success, you no longer belong to the little place where you started, to the little part of west London where you were brought up or played. So you lose something of that when you become a success.

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KING: That's Mick Jagger tomorrow night, full hour.

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KING: Tonight top 25 LARRY KING LIVE moment is from 1998. It's our Emmy award winning interview with Carla Fay Tucker, who was about to be executed in Texas for murder. Watch.

(BEGIN VIDEO CLIP)

KING: In this prison, does it get worse every day?

CARLA FAY TUCKER, EXECUTED FOR MURDER: No, it gets a little more exciting every day. A little --

KING: Interesting choice of words, Carla.

Prison interviews are always difficult. That was an especially difficult one because of the glass separating us.

TUCKER: Unfortunately, two people were killed with --

KING: And brutally killed.

TUCKER: Brutally.

KING: How to yourself do you explain that?

It was her and her friend. She did it with a pick ax. She hurt the other person and killed one person.

Did you envoy the violence.

TUCKER: At that that time I was very excited about doing different crazy, violent things, yes.

KING: She would subsequently be executed by Texas.

GEORGE W. BUSH, FMR. PRESIDENT OF THE UNITED STATES: God bless Carla Fay Tucker and God bless her victims and their families.

KING: George Bush saying that he watched that interview. And when while she was very sympathetic, he kept thinking of the family. But he did what he thought a governor had to do.

What's it like to kill someone?

TUCKER: It's horrible. I try not to take myself back to that night. We're the ones who put them through it. I'm the one that did that to them. So while I wanted to be angry, I couldn't be.

KING: People were pleading for her life all over the world, including the Pope, Pat Robertson because she had converted to Christianity. She was very believing. While she was frightened, she believed she was going to go to a better place.

TUCKER: It's a blessing to be part of it. And it's exciting to know that God has a plan for this.

(END VIDEO CLIP)

KING: Pick your top five moments at CNN.com/LarryKing. What about Blue Tooth, headsets, speakers? Can technology keep you safe? Some answers next.

(COMMERCIAL BREAK)

KING: According to the Food and Drug Administration website, scientific evidence does not show a danger to any users of cell phones from radio frequency exposure. But if you want to minimize your RF exposure, the FDA recommends the following: reduce the amount of time you spend using the phone, use the speaker phone mode or use a headset to place more distance between your head and the cell phone.

In that regard, with a few moments left, we welcome Mike Foley, executive director Bluetooth Special Interest Group. He's an electrical engineer and a wireless expert. What is that you have there?

MICHAEL FOLEY, BLUETOOTH SPECIAL INTEREST GROUP: Sure, these are two examples of wireless headsets that you wear in your ear to take phone calls. So then your phone can remain in your pocket, in your purse, in your briefcase, and then you don't have to hold it to your head. Many new cars now have Bluetooth built in as well, where it uses your speakers for basically a hands-free kit in the car. Of course, everyone is not going to go out and buy a new car, so you can get aftermarket Bluetooth speaker phones as well to use in the car. These you can clip these on the dash right above your head. You can make the call and not, again, have to hold the mobile phone to your head while you're driving. Of course, while you're driving, that's the law in many states and many countries around the world as well.

KING: What are your thoughts on the study released tomorrow?

FOLEY: I found it very interesting listening to the experts, and thought it was very confusing. I don't think they really know right now. And the other thing I didn't hear any of them talk about all of these were phones from 15 years ago, 10 years ago because they're 10- year studies. Think of what your phone was like 10 years ago, Larry.

KING: I think I still have the same one.

FOLEY: You're the exception. Most people in America in a ten-year period would go through four to ten cell phones. And they transmitted with a lot more power back then than they do now. Like everything, the technology changes over time. And how you fit that into the study is very interesting.

KING: What's the difference in the power transmission between a cell phone and Bluetooth?

FOLEY: A bluetooth headset or speaker phone uses approximately one one thousandth of the power.

KING: One one thousandth?

FOLEY: Exactly. It does depends on your mobile phone and Bluetooth headset. But, give or take, that's roughly the amount.

KING: I believe Dr. Ottis Brawley is still there. Are you there, Dr. Brawley?

BRAWLEY: Yes, I am.

KING: What do you think of the Bluetooth?

BRAWLEY: I think that for people who are concerned about cell phones concerning brain tumors, using a Bluetooth or a wired device is a very reasonable thing to do. I don't want people to be panicked and not use their cell phones over all of this, or be confused. If you're concerned, use a wireless device or a Bluetooth.

KING: Isn't you safer? Wouldn't you be safer using a Bluetooth?

FOLEY: It sounds like it. I'll leave that up to the medical experts. But if you can use something that uses one one thousandth of the power, and it really doesn't change your use patterns -- just put this on and take the call like you normally do -- why not do that. It seems prudent to me.

KING: Quickie, where did it get its name?

FOLEY: Bluetooth was a Danish king around the 900s. And he united the Scandinavian countries. The original concept with Bluetooth was it was a technology that would unite the mobile phone and personal computer. And Bluetooth was originally created by people in those countries at Eriksson and Nokia. So that was the code name and it stuck. It's been the name for over a decade now.

KING: You can buy these anywhere?

FOLEY: Sure. Any electronic store, you mobile phone provider store, they all have headsets, car kits. Of course, as I mentioned, most new cars come with it now.

KING: One one thousandth?

FOLEY: Yes.

KING: Thanks, Mike. Thanks, Dr. Brawley. Thanks to all of our panel. We're going to do a lot more on this.

Mick Jagger tomorrow night. "Anderson Cooper 360" right now. Anderson?