Can Cell Phones Damage Our Eyes?

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."

Scientists at the U. Washington have shown similar

[ReformedExCon]

I believe that the UW study was on the affects of cellular radiation on mice, and the results were equally disturbing. The exposed mice were invariably stricken with cancer while the unexposed mice remained at the norm.

But that study also showed that such effects were only engendered when the amount of radiation was both high and prolonged. The bovine lenses in this article were exposed to cellular radiation for 22 hours a day. If the exposure intensity is to be believed, then the transmitting antennas were placed right against the eyeball.

Neither of those situations is remotely near what normal cellular phone usage patterns resemble (unless you are a teenage girl, I suppose, but even then you aren't sticking the phone in your eye) (are you?).

So more study is necessary. The edge cases like the ones in the article and the UW study are very important to know, but the results of real-world testing ought to be examined as well. If we see a huge increase in the number of cancer and scratched lens cases in the coming years, there may be some validity to these studies.

I'll continue using my cellular phone, though. The convenience is just too great to pass up.

Re:Cell Phones are not new

[cagle_.25]

Not exactly. The FDA limit was fixed in 2000; most phones fall within 25% to 100% of that limit, with digital phones lower than analog by a rough factor of 2.

Here [cnet.com] is an exhaustive list of radiation exposures.

Re:What about Wi-Fi networks?

[Detritus]

Wrong [zyra.org.uk].

Re:Scientists at the U. Washington have shown simi

[Anonymous Coward]

Their findings are consistent with anecdotal evidence described in the IEEE Standard titled "Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz." (IEEE C95.1). There they mention that heating can cause clouding (bubbles?) in lens material. See http://www.rfsafetysolutions.com/IEEE_standard.htm [rfsafetysolutions.com] for an overview of the standard. The main concern at lower frequencies, 1 GHz included, is penetration of the RF into tissue and subsequent heating or other effects. The standard was set to be an order of magnitude below perceptible heating (i.e., 10x below a level that could change the tissue temperature by say, 1 deg C). The standard was also for whole-body exposure, but was updated recently to include specific calculations for the Pinna (ear). No mention about eyeballs/lenses in that later doc. So, if you look at the IEEE standard for "uncontrolled" environments (i.e., something similar to being in a room with WiFi constantly on), you'll see that the threshold for safe exposure is about 5x lower (at 1GHz) than the level the researchers used in the Israeli study. I'd be surprised if there are any Wi-Fi hot spots that have a power level approaching the IEEE standard threshold limit. It would be very interesting to compare their results to a lower dose that's below the standard safety levels. Note that some PCMCIA format wireless RF cards have power levels of 2W, (at 2GHz), i.e., a thousandfold the power level of the Israeli study. Perhaps you should also be concerned about putting your eyeballs too close to your laptop when you're on the cell phone net!

Re:Everybody hurts

[fatboy]

As I understand it, water is resonant in the infra-red portion of the EM spectrum. Microwave ovens use 2.4GHz because at that frequency RF energy is absorbed by water, but not my plastics and ceramics.

BTW, I am a radio amateur as well. DE KE4PJW

Re:I'm Asking Nicely

[Osty]

Anyway, I'm begging here: Can't we please have a Roland Piquepaille section so we can filter this stuff out? I'm not saying anything negative. I'm sure he's a wonderful guy and has a tremendous singing voice. I just don't want to read his blog.

The Slashdot editors are slow (in more ways than one). Do it yourself [daishar.com] (requires Greasemonkey [mozdev.org] for Firefox or Turnabout [reifysoft.com] for IE (be sure to get the advanced installer so you can add new scripts), and may be compatible with Opera 8).

And yes, I use my own script. I just decided to slum it and pimp my crap :)

Re:Everybody hurts

[modecx]

The thing is, 2.4GHz isn't anywhere close to the resonant frequency of the bonds in water, which IIRC is around 8-10GHz, but is almost unmeasurable because it varies rapidly, so it's a ballpark figure.

The fact is: if you put energy into a system, the stuff in the system gets hotter. It dosen't really matter if it's 10Ghz, 10Mhz or anywhere in between.

As long as it gets absorbed, it makes the object hotter. 2.4 Ghz was chosen because it's in the unliscensed band and microwaves used to leak quit a bit of RF, and also because it will penetrate food well enough to heat something largish. It's sort of a sweet spot. Higher frequency waves would be absorbed nearer the surface, and lower frequencies were in demand for communications, though they'd work about as well, apparently.

So, there you have it.

Had me worried until I read...

[aztektum]

As this study has not been not done -- yet -- on humans...

Seeing as how the study has been conducted on humans and I haven't heard anything bad, I breath a sigh of relief. However if it said the study has not been done on humans, I might be slightly concerned.

What...? You don't say.

Re:All danger is relative

[Dun Malg]

Consider when the commercial airline industry was younger and after a number of aircraft crashed, they discovered metal fatigue. If slashdot had been around then I'm sure half of the slashdotters would have spewed the usual "what are we supposed to do, get rid of aircraft technology" crap. But fortunately nobody in the real world did that - instead, they simply figured out a way to build aircraft from better materials, and made safer aircraft. Thanks to the studies that helped us understand the metal fatigue problems, we now have all the same benefits of commercial airline technology, with far fewer risks than it used to have.

Not a very good analogy. Metal fatigue was a well-known in the early jet age and didn't require "discovery"; also, it's not something that has been solved. You're probably thinking of the the de Havilland Comet crash in 1954, where fatigue cracking at the corners of the square windows resulted in catastrophic decompression. The Comet windows were squared essentially for cosmetic reasons-- no other aircraft manufacturer was dumb enough to stray from the tried-and-true round design. The problem was solved by letting engineering take precedence over appearance. As far as metal fatigue goes, there's not way around it. It's still a major cause of plane crashes and thousands of man hours are spent inspecting aircraft structural members to catch the signs of fatigue early.

Re:There is no need for speculation.

[Anonymous Coward]

Bollocks. I am a physicist. Firstly - GHz radiation can interact with matter no problem - think of NMR and ESR, for a start. In addition, they can drive molecular motion - hence the microwave oven analogy. Speaking of microwave overns, they do not focus, they cavity resonate - they do this because they want to cook evenly though a large object, rather then heat a small area unevenly. Cellphones want to radiate broadly for minimum directionality, but near the phone, you could be covering an appreciable amount of solid arc with matter. Secondly, the quantum energy is unimportant if you just want to calculate power transfer and directionality. Quantum energy is important in selecting the interaction mechnism, yes, but 1 watt radiative power is 1 watt radiative power, no matter how many eVs the quantum. Consider heating with one big flame compared with several small flames, if you can't get the physics directly. Thirdly, I think it's an open question, and if it is an effect, it's very low level, otherwise we'd see some conclusive evidence by now.

Re:There is no need for speculation.

[Anonymous Coward]

As a physicist working in EM design for MRI, I'd just like to second that Bollocks.

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.

What are you talking about? There are several very good human head models out there, mostly derived from the visible human project (HUGO, et al), which are used in SAR/heating models. You use something like FDTD or TLM to figure out the E field in the head, then you can work out SAR based on tissue properties.

Yep, that all works, and gives you lots of information about heating. But it isn't even nearly the whole story. Have you ever considered the biochemistry going on in your head right now? There's all kinds of stuff going on. And yes, it can be affected by electric and magnetic fields. Figuring out exactly how, and if it's important is a big, wide open question. If you go to the literature, you'll find most studies say "this is complicated and we can't really say anything conclusive".

Traditional SAR studies look at bulk heating, and are well known. The unsolved puzle is what happens on the microscopic scale. It's facinating stuff - and there's plenty of room for new research.

Re:Thermal?

[tgibbs]

From reading TFA (I know, I guess I'm not typical), they went to some lengths to make sure there was minimal temperature rise, as that wasn't what they were trying to look at. Their thermometer measured to 0.1degC. They held the temperature at 35degC and didn't see a temerature rise.

As it happens, I did read TFA, although I was unable to get access to the complete original reference. All it said in TFA was that "The entire system is placed in an incubator maintaining constant temperature for the duration of exposure." This is not necessarily adequate to maintain constant temperature within the chamber, which depends on how well the microwave energy is absorbed in the chamber, as well as how rapidly heat is conducted out of the chambers. They appear to be surrounded by air, so they are obviously better insulated than a lens in a body, which is effectively a big constant temperature water bath. A thermometer in the incubator would not necessarily measure the temperature in the chamber next to the lens. The illustration provided shows no temperature measuring device in the chamber itself.

Re:That attitude is pretty stupid

[Bad_Feeling]

This happens because of what is referred to as intermodulation or just intermod. Even though the phone's frequency is waay out of the frequency of the audio transisters in your speaker's amp, the power level at that short distance is enough to overload the transisters and push them into what is called the non-linear region. In this region, the transister acts like a diode or am radio and rectifies the signal from the cell phone. As such many different frequencies are produced inside the transsiters, some of which fall into the audio spectram that you hear.