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Wireless Networking Hardware

Can Cell Phones Damage Our Eyes? 429

Roland Piquepaille writes "I'm sure you've read dozens of stories about how our cell phones could be dangerous to our health, causing brain tumors for example. But so far, there is not a definitive answer. But now, according to IsraCast, a team of Israeli researchers has discovered that the microwave radiation used by our cell phones could destroy our eyes by causing two kinds of damages to our visual system, including an irreversible one. If the researchers are right, and even if you only occasionally use your cell phone, the lenses in your eyes can suffer from microscopic damages that won't heal themselves over time. As this study has not been not done -- yet -- on humans, I guess the controversy can begin and that another scientific team will soon tell us that this study is not correct. In the mean time, read more for other details and references. And whether you think that cell phones can damage our eyes or not, feel free to post your comments below."
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Can Cell Phones Damage Our Eyes?

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  • by Teckla ( 630646 ) on Wednesday July 27, 2005 @10:30PM (#13182376)

    I'm exposed to an 802.11b network all day at work, and exposed to another 802.11b network all night at home.

    Should I be worried? Does anyone know if being exposed to 2.4 GHz emissions might also be harmful?

  • Missing parameter (Score:4, Interesting)

    by Muerte23 ( 178626 ) on Wednesday July 27, 2005 @10:40PM (#13182435) Journal
    They say they exposed the eye tissue to 2.2 mW of radiation at 1.1 GHz. But 2.2 mW over what area? the room? One micron? The ~100cm^2 device in their setup? The important unit is *intensity*.

    How much energy per area hits my eye from my cell phone in comparison? They don't say. That's a very important free parameter that they can vary to cause sensationalism where there may indeed be no danger.

    It would be more useful if someone calculated this in burnt Libraries of Congress per century per square cubit.

    Also, looking back at the article, they have the eye tissue sample in some sort of transmission line resonator. They don't go into specifics, but such a device could increase the power density of the microwaves by several orders of magnitude over that of a point emitter.

  • Thermal? (Score:4, Interesting)

    by tgibbs ( 83782 ) on Wednesday July 27, 2005 @10:47PM (#13182491)
    I'd need to be convinced that this is relevant to lenses in an animal. It sounds a lot like thermal damage, so we need information about the temperature reached in the chamber and how the thermal conductivity of the chamber compares to the body. If you continually pump microwave energy, no matter how low in intensity, into a sufficiently well insulated chamber, you'll eventually manage to heat it up enough to cook a lens.
  • Re:Missing parameter (Score:3, Interesting)

    by cagle_.25 ( 715952 ) on Wednesday July 27, 2005 @11:13PM (#13182639) Journal
    The FDA [] measures the radiation as a "Specific Absorption Rate", SAR = W/kg of body weight, averaged over the mass of a typical head. So if you have a large enough head, you can talk all you want.
  • by dustmite ( 667870 ) on Wednesday July 27, 2005 @11:21PM (#13182683)

    I'm 28 and although I've been short-sighted for a little over 15 years, my vision has deteriorated still somewhat during the last few years. This is almost certainly due to staring at the computer monitor for long periods each day without taking breaks. My optometrist agrees. A large percentage of people with jobs that require long periods of concentration at short distances develop eyesight problems quickly - this stuff is known, ask your eye doctor. The fact that there are exceptions like yourself does not mean it isn't true, as any first-year stats student will tell you, you can't determine much with a statistical sample of size 1.

    Ask law students how many of them go in with perfect eyesight and need glasses within a few years of study. They spend long periods concentrating on thick books full of tiny text.

    The trick is to take regular breaks, e.g. once an hour to spend a few minutes focusing on something in the distance. (If you are a smoker, then you probably already take frequent breaks while on the job.)

  • Re:Everybody hurts (Score:4, Interesting)

    by anagama ( 611277 ) <> on Wednesday July 27, 2005 @11:24PM (#13182703) Homepage
    I recently built a cantenna and as you can imagine, spent a lot of time googling. I did find this, from here [], to be a bit disturbing ... but plowed ahead anyway:
    As if this was not yet enough to keep you from messing around with fast flying electrons, I have received many emails from folks who are very involved with HAM radio and other professions and hobbies that involve work with high frequency microwave radiation. They warn that 2.4 GHz just happens to also be the resonant frequency of plain old water. This is why a microwave oven works. The energy of an 802.11b device is the same kind of energy that cooks your food, but on a much smaller scale. This is important considering that we as humans are 98% made of water. I have been warned that exposure to even as little as a 1/4 watt amplified with a 14db antenna, such as described here, could lead to severe vision problems and possibly other health issues.

    After spending yesterday at work with only my perscription sunglasses (forgot my clear ones at home), and becoming increasingly frustrated throughout the day from my inability to see (either too dark but crisp, or bright enough but blurry), I'm considering further precautions.
  • by AKAImBatman ( 238306 ) * <akaimbatman&gmail,com> on Wednesday July 27, 2005 @11:30PM (#13182730) Homepage Journal
    The only reason why cellphones haven't been literally cooking our brains is because they aren't powerful enough to produce any immediate noticeable effects

    Well, that and the fact that there's a thick skull plate in the way. Radiation decreases by the inverse square of the distance, but it can also be shielded against by thick and/or dense materials. The more molecules you throw in the way, the more likely the radiation will be stopped.
  • by zenyu ( 248067 ) on Wednesday July 27, 2005 @11:34PM (#13182745)
    No, I wouldn't think so. I think the danger of the cell phone emissions is the fact that they are so intense (seeing as they originate right next to your head). Unless you live with an AP right next to you all day, it's not going to matter, as these waves lose their intensity quickly with distance.

    It's not the AP you should be worried about, but the WiFi card in the laptop. But the answer is still the same, MUCH less radiation plus it is far from your head. Most of EM will go right into your left or right leg muscle, where it is unlikely to cause any damage. Plus there is the R^3 fall-off, after a couple inches 0.033-0.2 Watts is nothing. The problem with cell phones is that they emit up
    to 2 Watts and their transmitter antennas are used right very near some important organs such as the brain, eyes and ears.

    Though I bet in 10-20 years when we figure this out, the solution will probably be something as simple as making the antenna directional away from your head. It means you need a few more cells, but by then we'll more cells for capacity reasons anyway, so this will all be seen as a blip on the health radar like all the kids who had thyroid problems when we first started testing nukes. Because of them we even figured out how to reduce the natural cases of those same thyroid problems. So, assuming you use a cell phone or WiFi device, just consider yourself a Guinea pig who might very well benefit our children by participating in the discovery some new and unusual disease.

    You are much more likely to be killed by someone plowing their car into yours than all the health risk combined. The average American is in something like 1.4 car accidents in their lifetime, or 1.6% accidents a year. About one in a hundred of those result in death. Except for eating (heart attacks) and smoking (lung problems), nothing even comes close to being able to shorten your life as efficiently. This is something to study, so we can reduce the number of deaths.
  • by NormalVisual ( 565491 ) on Wednesday July 27, 2005 @11:49PM (#13182821)
    The decay of the radiation is obviously cubic over distance, but where most are held, right next to the eyes and brain, the radiation is quite strong. At certain times such as call initialization it's very strong, strong enough to light batteryless LED accessories popular on some phones.

    It's strong enough such that when I have my cell phone within a foot or so of my old-school CRT display, I can tell when it's going to ring several seconds in advance because of the substantial disturbance of the monitor image.

    I'm wondering why this is news though - it's been known for decades that RF is *not* good for your eyes and can contribute greatly to cataracts (that's why waveguides generally have all kinds of warnings about not looking into them), so I think a little common sense would probably go a long way here.
  • Re:Well... (Score:5, Interesting)

    by linzeal ( 197905 ) on Wednesday July 27, 2005 @11:53PM (#13182844) Homepage Journal
    They work in Canada [], but the US has not moved ahead with their graphic warning campaign.
  • Re:Everybody hurts (Score:5, Interesting)

    by Dun Malg ( 230075 ) on Thursday July 28, 2005 @12:10AM (#13182932) Homepage
    The energy of an 802.11b device is the same kind of energy that cooks your food, but on a much smaller scale. This is important considering that we as humans are 98% made of water.

    FWIW, it's fairly irrelevant that the human body is 98% water. Microwaves only heat water-- they don't transform it into Horrible Eye Poison or anything. Most of the human body can handle a little microwave heating. It's really only the eyes that can't handle it, essentially cooking like the whites of an egg.

  • by Kohath ( 38547 ) on Thursday July 28, 2005 @12:29AM (#13183051)
    - Cell phones are for topical use only
    - Not for Ophthalmic use
    - Intentional misuse by deliberately concentrating and inhaling a cell phone may be harmful or fatal, but should otherwise be safe for your eyes.
    - Avoid contact with eyes, scrotum, or mucus membranes
    - Do not use cell phones as an ice cream topping
    - Do not use cell phones if allergic to cell phones
    - Caution: Contents under pressure
    - Cell phones are for indoor or outdoor use only
    - Cell phones are not dishwasher safe
    - Do not eat cell phones
    - Do not burn cell phones for light
    - When not in use, store cell phone in a pocket, not in your eye
    - Cell phone camera lens is not to be used as a substitute for a contact lens
    - Cell phone use in movie theatres may result in black eyes

    Use as directed. This is not a step
  • by garote ( 682822 ) on Thursday July 28, 2005 @01:26AM (#13183272) Homepage
    Tell your friend to call you on your cellphone, after waiting a random amount of time between 30 seconds and a minute. Open your eyes and find some object with a relaxed focal point. Hold your phone straight up, off to the side of your head. Not quite against your ear, but out a ways.

    Wait, and relax.

    I don't know about you, but after trying this experiment a couple of times, I found that I could tell when my phone was about to ring, because I felt a very slight stinging sensation near the front of my eyes a few seconds beforehand.

    That cannot be healthy.

  • by Anne Thwacks ( 531696 ) on Thursday July 28, 2005 @04:10AM (#13183709)
    a little common sense would probably go a long way here

    Quite possibly, but completely irrelevant.

    A survey I did a few years back, shows conclusively that radiation from mobile phones utterly destroys common sense at 30 paces, unless you are wearing a tin-foil hat! This explains the connection between mobile phone usage and car accidents, according to Police Officer Dibble, and the Local Inquirer.

  • by AB3A ( 192265 ) on Thursday July 28, 2005 @07:51AM (#13184257) Homepage Journal
    Bollocks. I am a physicist.
    Well, I'll stack my electrical engineering degree and three decades of experience against your physics degree(s) any day. :-)

    You're right. There are resonances. Modeling the near field effects of cell phone radiation is not simple.

    Were I constructing an NEC model to evaluate cell phone safety, I might try taking an NMR scan of a person's head and using the assumption of antenna reciprocity to figure out heat absorbtion. It's not a perfect assumption as we know because the nuclear resonance frequencies can change based upon many things, but it would put us in the right ballpark for the sake of making general policy.

    Second, keep in mind where the antenna is: It's on the side, toward the back of your head when your phone is close to your ear. It's nowhere near your eyes. Couple that with the likelyhood that the phone is running much less than 300 mW (the maximum power these things put out) wherever cell coverage is good, and the total risk is quite small.

    I've seen many studies come and go. This latest Israeli study is yet another one for the pile. It may well be true that some parts of the body (such as your eyes) are more sensitive to microwave radiation than we first thought --but this research ignores that fact that most phones don't put anything close the levels of radiation he used near the eyes.

    If it were true, vast segments of society would be quite blind by now. It hasn't happened. I am not worried.
  • by Bloke down the pub ( 861787 ) on Thursday July 28, 2005 @08:22AM (#13184383)
    I did my quantum physics courses in the university some time ago, but this I remember clearly: Professor said that absorption is heavily frequency dependent thing and therefore cellular phones shouldn't be a problem.
    Huh? Some GSM networks run on 1800MHz which isn't so far off.
    So I propose someone built a 2GHz or 3GHz microwave oven,
    Assuming it's true that the frequency for wi-fi is close to that of microwave ovens (deliberately chosen, as it's a 'dirty' band that nothing critical uses) I have one in my kitchen.
  • by evbergen ( 31483 ) * on Friday July 29, 2005 @10:33AM (#13194673) Homepage
    Biological tissue is not just your average beef steak, you know -- biological tissue can also refer to the huge parallel DSP with certain lofar-like properties that is your brain.

    The is no mechanism for low power, 'low' frequency electromagnetic radiation to directly affect covalent bonds. Agreed. Cell phones don't produce enough watts to heat you up enough to cause serious heat damage. Agreed.

    But if you consider that a low intensity, 15 Hz flash is enough to give some people epileptic seizures, while they can easily stand the intensity of the continuous sun, then that gives me some reason to suspect that a signal's low frequency envelope and the disturbance that can cause on the oscillating processes that take place in your brain and even in simpler cells is the thing to look out for here.

    Personal experience has made me quite cautious with pulsed broadband microwaves, especially if the pulse frequency is below a few hundred Hz.

    You Wi-Fi worshipping USians may not believe it, but I personally hear high pitched noises (akin to the PAL 15 kHz flyback frequency hou hear with old TVs) and/or experience subtle memory and concentration losses around plain 100 mW 2.4 GHz Wi-Fi APs.



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