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University Bans wi-fi as Health Concern 693

Posted by samzenpus
from the microwaves-still-ok dept.
BaltikaTroika writes "A Canadian university has banned wi-fi, since the university President sees a possible link between electric and magnetic fields and brain tumors. According to the head of the university, "the jury's out on this one, I'm not going to put in place what is potential chronic exposure for our students." Is anybody outside of this university's administration concerned about this?"
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University Bans wi-fi as Health Concern

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  • by Anonymous Coward on Thursday February 23, 2006 @02:04AM (#14782611)
    Gee, where have we all been hearing THAT phrase lately?

    Fact: Nobody has ever demonstrated in a repeatable, peer-reviewed, properly-controlled study that low-level RF radiation at nonionizing wavelengths has any biological effect whatsoever. For every study that shows correlated effects, two more show none at all.

    Fact: WiFi adapters, even the gray-market 100 mW jobs you buy on eBay, transmit 1/10 to 1/100 the power of a cell phone.

    Fact: Your microwave oven leaks more 2.4-GHz energy than your WiFi card emits intentionally. For best results, cut a 1" slit in package wrapper and rotate dish after 2 minutes on HIGH.

    Fact: DNA damage from 2.4 GHz radiation at athermal levels would require a form of matter-energy interaction that is currently unknown to physics. There's a guaranteed Nobel Prize for anyone who can document such an interaction, because as far as anyone knows, we pretty have all the fundamental interactions covered at this point. Get cracking!

    (Probable) fact: This joker has some sort of financial interest in a local commercial ISP whose business would be threatened by a campus-wide network. Nobody that stupid runs a university... but conflicts of interest aren't exactly unheard-of in that line of work, are they?
  • by Anonymous Coward on Thursday February 23, 2006 @02:13AM (#14782646)
    More precisely, radiation between an isotropic point-source emitter and receiver falls off as 1/r^2.
  • by chriswaclawik (859112) on Thursday February 23, 2006 @02:59AM (#14782826)
    Quick lesson: EM field from a point source: 1/r^2 strength EM field from a line/wire (theoretically infinite): 1/r strenth EM field from a plate (theoretically infinite): constant strength The derivations involve many repulsions and attractions of charges as you integrate along an entire line or plane. This is stuff you should know after learning multivariable calculus.
  • Re:DIfference? (Score:3, Informative)

    by putaro (235078) on Thursday February 23, 2006 @03:01AM (#14782834) Journal
    Your analogy is retarded and refutes itself. Radio frequencies and visible light are all part of the electromagnetic spectrum and are carried by photons. Visible light is a *HIGHER* frequency than microwave radiation. Therefore by your reasoning visible light is more dangerous than microwaves.
  • by non-poster (529123) on Thursday February 23, 2006 @03:18AM (#14782891)
    cell phones often get above 1 Watt of output.
    False!

    Maybe old analog phones. Modern digital phones are rated at a maximum output of 200 milliwatts. I've read that the typical output is somewhere between 1 milliwatt and 5 milliwatts. I've studied more about CDMA phones than other technologies, and I think they adjust the output power every 40 milliseconds, based on the signal strength of the receiver (tower).

    What's the typical power output of a cordless phone in the house? I'm guessing it's more than 5 milliwatts.
  • by Raindance (680694) <johnsonmx.gmail@com> on Thursday February 23, 2006 @03:27AM (#14782925) Homepage Journal
    I'd suggest taking a look at CNET's cell phone radiation chart [cnet.com]. Updated Feb 22, 2006.
  • by XchristX (839963) on Thursday February 23, 2006 @03:49AM (#14782984)
    [quote]
    "well that's ok, because the study was about Electromagnetic fields, not magnetic
    fields, which are two different things. As far as I am aware, there is absolutely nodanger to humans from a magnetic field."
    [/quote]


    Wrong. All Electric and Magnetic Fields are the same thing. They are components of the same EM field Tensor.

    F_mu_nu=del_mu(A^nu)-del_nu(A^mu)

    Where A is the 4-vector Potential (ie the scalar potential & the regular magnetic vector potential).


    All quantities here are 4-vectors/tensors with a Minkowskian metric:

    g_mu_nu=diag(1,-1,-1,-1)



    F has 6 independent components, 3 being the electric field components, 3 being the magnetic field components.

    The above expression, together with Maxwell's Equations:

    del.F=J
    del~.F=0




    are manifestly Lorentz Covariant equations, meaning they are invariant under a Lorentz Transformation. This means that, since the lorentz transformation is unitary, & can be written as:

    F`=L_dagger*F*L

    this will leave Maxwell's equations unchanged. Thus, if you have a pure magnetic field (like that of the earth) with the 3 E's in F being 0, it is always possible to construct an L st F` has nonzero E's. L is a Lorentz Transformation, so the physical significance is that you can always transform relativistically to a frame of reference where a magnetic field picks up an electric field and even radiation EM fields (such as Lienard-Wiechert potentials), making it an "electromagnetic" field.
  • by m6ack (922653) on Thursday February 23, 2006 @04:05AM (#14783021)
    This sounds like a troll, but i'll bite -- because many people don't really understand what our environment really looks like in the RF domain and what the real concerns are. We have cell phones that typically radiate power at ~836MHz Cell, ~1900MHz PCS, or 2.xGHz for GSM that can radiate close to the ear at 28dBm (or roughly 1 Watt). We have microwave towers that even though they are directional can leak energy. We have microwave ovens that leak energy at roughly 2.4GHz -- enough to easily jam 802.11b. You don't know it, but there is a lot of communication going on over power lines today as well. Wifi does not comparitively add enough energy into the environment to be a very significant contributor. 2.2x-ish MHz is a significant frequency because it is a resonant frequency of water. That's the reason that a microwave oven works -- electromagnetic energy supplied at this frequency causes the water molecules to get all excited and generate heat that cooks (steams) the surrounding food. Microwave ovens are shielded -- but imperfectly & some energy does escape. Our bodies can be affected by this energy, because we are mostly made of water. Even so, by and large, with the intensities that are in our environment (outside the oven), the heat that is generated doesn't really even warm the first layer of skin. In cell phones, where the source is closer to the head and there is greater power, I have heard that the radiation can penetrate farther into the head and warm some of the brain close to the ear. So, if you are really thinking of banning something due solely to electromagnetic radiation, look also at banning these: 1) GSM Band Cell phones. 2) PCS Band Cell Phones. 3) CELL Band cell phones. 4) Microwave ovens. 5) Nearby Cell Towers 6) Nearby Microwave communications antennas. 7) High voltage Power lines. And let's not forget banning on-campus AM radio stations and secuity Walkie-talkies in the process... they likely put out more power to a limited portion of the student body than 802.11. One further note -- if you are really paranoid about 802.11b and will not be asuaged -- later versions of 802.11 spec output power at 5.2GHz. This band is not one that is even closely related to a resonance frequency of water & may help to calm your paranoia with the standard wi-fi frequencies.
  • by canajin56 (660655) on Thursday February 23, 2006 @04:06AM (#14783024)
    There is a widely discussed problem called electrosensitivity, or ES. Thousands of people suffer from it. However, searching the internet, I can find no articles on it other than conspiracy sites that claim that millions of people are affected, and the government and medical industries keep it secret because they love their cellphones. In fact, while these website site all of these journal papers and conferences on the subject, there references appear to be completely fabricated to make them seem plausable. The only actual scientific articles have asserted that such a syndrome does not exist. Several groups in the UK and the USA have conducted double blind tests in which sufferers are secretly exposed to EMR of frequencies like that they claim cause their symptoms (Monitors, cell phones, etc), and they did not react. On the other hand, when exposed to a radio device they are told is active, but which is nothing more than a box with a light, they react immediatly. These studies are dismissed by the ES campaign groups, who declare they are secretly funded by the cellphone companies. Some even declare that all scientiests are against them because scientists love computers and other electronic gadgets, and all scientists will forever bury the mounds of evidence.
  • by XchristX (839963) on Thursday February 23, 2006 @04:23AM (#14783074)
  • by Anonymous Coward on Thursday February 23, 2006 @04:38AM (#14783122)
    Try wikipedia:
    Microwave Oven [wikipedia.org]

    A microwave oven works by passing microwave radiation, usually at a frequency of 2450 MHz (a wavelength of 12.24 cm), through the food. Water, fat, and sugar molecules in the food absorb energy from the microwave beam in a process called dielectric heating. Most molecules are electric dipoles, meaning that they have a positive charge at one end and a negative charge at the other, and therefore vibrate as they try to align themselves with the alternating electric field induced by the microwave beam. This molecular movement creates heat. Microwave heating is most efficient on liquid water, and much less so on fats, sugars, and frozen water. Microwave heating is sometimes incorrectly explained as resonance of water molecules, which only occurs at much higher frequencies, in the tens of gigahertz.
  • by coofercat (719737) on Thursday February 23, 2006 @06:01AM (#14783334) Homepage Journal
    This guy's obviously a bafoon, but he's got half a point (misdirected, but still...). I think we all know the link between mobile phones and cancer (despite what the telcos say). There's also a suspected link between mains electricity (and it's associated fields) and cancer:

    http://www.telegraph.co.uk/news/main.jhtml?xml=/ne ws/2002/10/06/nemf06.xml&sSheet=/news/2002/10/06/i xhome.html [telegraph.co.uk]

    So the point being, the frequency is irrelevant, it's all to do with the magnetic and electric fields. When one or both of these are far in excess of ambient, they cause problems.

    The new-age movement goes further to infer that all electrical devices give off 'bad vibes' in the form of positive ions (which make you feel tired, depressed etc). Clearly, transmitting devices are designed to propagate a signal, so it follows that they create more of these ions. Again, there's some science behind this, although arguable.

    It looks like this guy is a bit misguided, but looking out for such things. For it to be any use at all, he'd have to ban phones, high current cables, and most of the engineering department, oh, not to mention around about every computer on campus.
  • by Dolda2000 (759023) <fredrik@dol[ ]000.com ['da2' in gap]> on Thursday February 23, 2006 @06:41AM (#14783413) Homepage
    Regardlessly of whether water molecules resonate at 2.4 GHz or not, I still think that the GP's point is valid: EM waves at 2.4 GHz affects water enough to warm it. Of course, as the GP also did point out, the difference in transmission strength between a WiFi antenna and a microwave oven makes it a non-issue anyway, even ignoring the fact that just because it warms your body, it doesn't necessarily mean that it's cancerous.
  • by Anonymous Coward on Thursday February 23, 2006 @09:02AM (#14783706)
    In Sweden this is officially recognised as a possible health concern check out:
    http://www.feb.se/FEB/Links.html [www.feb.se]

      Also note that Sweden (the home of Ericsson) has one of the highest cell phone per capita of any nation.
    I have worked in a Swedish office where an employee has her room proofed for electromagnetic exposure at significant cost to the employer- and noone is allowed their cellphones on within 20 meters of the office.

    Try the world health organisation:
    http://www.who.int/mediacentre/factsheets/fs193/en /index.html [who.int]

    Personally I have formed no opinion on the risks involved here - I agree that there seems to be insufficient research - but there is certainly strong evidence indicating that a small percentage of people suffer from this condition.
  • Re:DIfference? (Score:2, Informative)

    by DavidTC (10147) <slas45dxsvadiv D ... neverbox DOT com> on Thursday February 23, 2006 @09:34AM (#14783853) Homepage
    To be absolutely clear about this: Cancer has nothing to do with 'frequency', at least, not in absolute terms. What causes cancer is a wavelength of radiation that goes far enough through the dead skin on your body (can't cause cancer in dead skin) and screws up your DNA once it does so.

    If it does not do that, it cannot cause cancer. If it does do that, it might cause cancer.

    The wavelength of radio stations and TV stations go through you. However, they are much much too large to have an effect on a cell...they are in the meter range. They can't cause cancer anymore than getting hit by a car can.

    In fact, anything much larger than the visible spectrum isn't going to be small enough to cause cancer. Although note that, not only are you transmitting on the wavelength you want, you are often transmitting on half that wavelength and double that wavelength, thanks to some reason I don't fully understand.

    Getting back to wifi, microwaves, and other gigahertz wavelength, which are smaller than visible light, go through your cells very poorly, tending to get stopped by water and the cell barrier. And, in effect, transmitting their motion to the water, heating it up, although you'd never notice unless you were standing inside a microwave oven, as most signalling methods in that wavelength are in or below the watt range.

    This is, contrary to what people think, proof that it is not harming us, because our skin can take a hell of a lot of heating before anything bad happens, and heat cannot cause cancer. (By the time you apply enough heat to screw up DNA, you've already killed the cell. Which is good, because otherwise people would get cancer from burns.) Moving water is much better than continuing forward and moving DNA.

    The current 'theory' about how cell phones mess you up has nothing to do with any of this, it's that EM fields somehow mess with chemical reactions in your body, reactions that are unrelated to DNA. That's magnetic fields, not radiation. When things move through a magnetic field, they generate electricity. (Erm, in essence, although that's a bit simple.) The theory is that cell phones generate a strong enough field that your head moving right there can generate enough power to mess up your head.

    Of course, this is completely idiotic, but whatever. It's basically the exact same claim as the one made living near power lines, which also has no evidence for it. The only place our body uses electricity is our nervous system, and if the minute amounts of electricity generated within us could screw that up, we'd have people having seizures every time they walked under a power-line transformer and stuff like that. There's no logical reason that long term exposure to minute internally-generated electrical current would have an effect, but short, extremely powerful bursts like walking through a power plant wouldn't.

    Although I did find it funny when I ran into someone who insisted cell phones were bad for you...and walked around with magnets in their shoe.

  • Re:Joule seconds (Score:3, Informative)

    by kidcharles (908072) on Thursday February 23, 2006 @10:27AM (#14784193)
    Joule-seconds...That's the dimension of Planck's constant - not meters-squared-kilogram per second

    They are equivalent:

    Joule -> kg m^2 / s^2

    Plank's constant = h
    Frequency of EM radiation = f -> 1/s

    photon energy (Joules) = h * f

    Since the unit of f is Hz or 1/s, Plank's constant can be represented with the units J*s or equivalently kg m^2 / s.

    QED
  • by Qbertino (265505) on Thursday February 23, 2006 @10:46AM (#14784373)
    I see a lot of wannabees rant about this university being run by unscientify crackpots. And that the sun and radio and tv is more radiation blah blah ...
    I've got news for you: Microwaves damage health. Period.
    The debate is at which intensity do they start doing that.
    I generally turn my Wifi of if I'm not using it and have stopped carrying my cellphone close to my body, since it's on all day. I turn it off at night. I also hold it away from my head when I make a call until the cell handshake is over and the remote connect is there. My Siemens M35 even has a beep to indicate when the connect is there. Smart people the Siemens engineers, aren't they?
    Handshake you ask? That's the high-power meep-meep-meep you hear in nearby active FM radios just before you make or recieve a call. It's what establishes the conection to the cell network for communication. I even know a woman who can sense the cellphone handshake (she has e-magnetic field sensetivity) from meters away and has the habbit of anouncing cellphone calls seconds before a phone rings. Fun to watch with unsuspecting others near by :-) . Her life isn't that fun though. When her neighbor above leaves his 20" CRT on she can't sleep. She's got other trouble with that aswell and people often don't believe her and think she's crazy.
    On it goes:
    My father was a high profile radar electronics engineer - with Military (Nato, Cruise Missile), Airbus, Nasa/Grumman Aircraft (Lunar Module, Space Shuttle, etc) and some others. He forbid us to have a Microwave oven (they ALL leak Microwaves) and steared clear and went the other way whenever we got to close to a radar bubble when going hiking.
    There are people who've had terminal brain tumors due to intense cellphone usage and I work with doctors (medical IT) who keep all equipment far away and well cased according to TCO.

    Bottom line:
    Don't think it's not unhealthy just because most people don't care. A little common sense and forsight is needed when handling technology. You don't get universal flawless wireless conectivity without a tradeoff. Anyone who believes that is a crackpot himself.
  • by Metaphorically (841874) on Thursday February 23, 2006 @11:36AM (#14784841) Homepage
    Nice way to engage in dialog.

    I also questioned the numbers since I remember that right when cell phone popularity started growing dramatically, there was a statement (in the manual of my Motorola flip phone) about the limits on maximum emission levels being raised recently. That was back in the early 90s.

    Anyhow, I think the number this guy quotes correlates to SAR which this list [cnet.com] claims goes pretty close to the 1.6 Watts SAR maximum level mentioned in the page you link to.

    btw, that list is the highest SAR levels mentioned from this other page [cnet.com].
  • by Raindance (680694) <johnsonmx.gmail@com> on Thursday February 23, 2006 @11:52AM (#14785017) Homepage Journal
    I can't speak to this ES phenomenon, nor your anecdotal argument, but it was documented in 2003 - and hasn't been successfully challenged by any new research, to my knowledge - that cell phone radiation seriously injures the blood brain barrier in rats. This was found to be the case for radiation levels similar to those found in modern cell phones.

    http://www.wired.com/news/wireless/0,1382,57488,00 .html [wired.com]
  • by phlegmofdiscontent (459470) on Thursday February 23, 2006 @12:03PM (#14785117)
    When dealing with radiation, most physicists like to use electron-volts (eV) instead of Joules (or m^2 kg /s^2). One eV is 1.602x10^-19 J, so Planck's Constant (h) becomes 4.14x10^-15 eV S. I ran some rough estimates using visible light (500 nm) and microwaves (about 3 cm). Visible light has an energy of 2.5 eV, or right at the low end of chemical reactions. Microwaves have an energy of 4x10^-5 eV which have no chance in hell of initiating chemical reactions. Other people have pointed out, though, that it is still sufficient for exciting molecules vibrationally, rotationally and in a couple other ways. It's still far too little to possibly cause health problems.
  • What an idiot. (Score:1, Informative)

    by Anonymous Coward on Thursday February 23, 2006 @12:46PM (#14785567)
    What an idiot.

    Cellphone Radiation = (Number of students) x 2W at all times ON EACH PERSONS BODY (remember, 1/d propogation)
    AM RADIO = Minimum for a station = ~250 watts (one town)
    FM RADIO = ~100W (for 15 miles or so, a generic radio station)
    Then add in terrestrial television (analogue and digital), cellphone tower radiation, microwave links, and all other background radiation.

    Wifi Radiation = (20-100mW Per access point) + (20-100mW per simultaneous connected user)

    Wikipedia says they have 7,600 students.

    That means that even with a theoretical super-network of 200APs with 20 external repeators jacked up high with large yagi antennae with 5000 students concurrently accessing it, you'd be using MAXIMUM (all APs at maximum and all students having maximum power cards to give an absolute maximum):
        100mW x 200 APs
    + 100mW x 5000 Students
    + 200mW x 20 APs
    = 20,000 mW APs + 500,000mW Students + 4000mW external connections
    = 524,000mW or 524Watts spread over the entire campus supporting up to 20 long-range connections.

    In comparison, this is the same amount of power that would be present if ONLY 3% (262) of the students had their mobile phones turned on with a *much* lower individual dosage being spread over a far wider area, so *much* healthier. Someone isn't thinking this through and is just paranoid about "electrosmog".
  • Why Not Ban Alcohol? (Score:2, Informative)

    by Coco Lopez (886067) on Thursday February 23, 2006 @01:04PM (#14785732)
    Firstly, let me just say that anyone from Ontario knows that Lakehead isn't a real university anyway...

    But, why not ban alcohol? It poses more real direct risk than WiFi. (see this report [apolnet.ca]) This smells like a cost-cutting measure wrapped in a big politically correct environmental/health and safety wrapper.
  • by sarkeizen (106737) on Thursday February 23, 2006 @01:05PM (#14785747) Journal
    I'm going to guess what the original poster is saying. That because the photon has a low energy it is far, far, far more difficult to interact with chemical systems. Gamma rays are different because they are HIGH energy photons. Gamma rays are not being produced here to any significant degree.

    Your study from pubmed demonstrates this point well. They were finding genetic damage at 1.2-2W/kg when exposed at >4h. So for the average american woman say (140lbs) this would be between 76-120W of exposure or somewhere between 3-5W for a newborn.

    Wifi runs from 40mW to...well I've seen things in the 120mW range. Consider that the worst case (120mW) is 25x smaller than the energy to have similar effect on a small newborn.

  • It's obvious (Score:2, Informative)

    by hausmaus (684529) <sean@outpostbbs.net> on Thursday February 23, 2006 @07:05PM (#14788848) Homepage Journal
    It's obvious that this is another incident of an "educated" person making a rash, inane and embarrasing decision without any knowledge of the subject they're making a decision on. As a US federally licensed amateur radio operator, it's part of the licensing exam for all three license classes to include a good portion of RF safety.

    If the good doctor would have bothered to check out the facts (such as what's at http://www.fcc.gov/oet/rfsafety/rf-faqs.html [fcc.gov]) before inserting his foot in his mouth, he would have read that it's very inconclusive that radio waves of any sort cause cancer. I use a handheld radio that transmits up to five watts of power within a few inches of my head and I've never had any problems. I've never heard of an amateur radio operator dying of cancer caused by his hobby either.

    As it's been said, everything causes cancer. Methinks that Der Fuhrer has alterior motives to shutting down Wi-Fi and everyone else suffers.

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