I have nothing to declare but my cheekiness

May 20th, 2006 by Ben Goldacre in bad science, dangers, electrosensitivity, medicalisation, patrick holford, powerwatch - alasdair philips, scare stories, very basic science | 121 Comments »

Ben Goldacre
Saturday May 20, 2006
The Guardian

I am routinely accused, in long and angry letters, of being in the pay of the pharmaceutical industry, the mobile phone industry, and the government. Needless to say I lap it up, and would never engage in similarly ad hominem attacks in return, since critiques of character and finance are a poor substitute for a sober analysis of the data.

Oh go on then.

Let’s say you were worried your health was being harmed by electromagnetic radiation, a notion that the newspapers are currently very keen to promote, with little heed to the facts, as we saw last week. Where would you turn?

Powerwatch might be your first step: they are quoted widely in the newspapers, after all. In 2000, in the Daily Telegraph, they estimated that “up to one in 100 people suffers from mild electrosensitivity, which can cause nausea, migraines, disorientation and blackouts.” By 2005 in the Daily Mail this had risen dramatically: “campaign group Powerwatch believes up to five per cent of the population is severely affected by electrosensitivity.”

When you got to their website, you’d pay £28 to sister organisation “EMFields”, run from the same address, to get full access to their vast array of complex scientific material. This might lead you to believe in the need to shield your house out. Luckily they can help you there too.

You’ll want to start with EMFields carbon screening paint, at £50.99 a litre: “one coat of this specialist paint stops over 99.9% of incoming radiation (900 MHz – 18,000 MHz)”. You’d get 3 square meters per litre on rough plaster. Oh golly. That’s an awful lot of very expensive paint. And then you’ll have to earth it all. With their £25 earthing kits. What about the curtains? You’ll need screening material at £43.94 a meter. Don’t forget the doors. Or any vents. Maybe you’ll want to fill the gaps. With foil tape. At £10.50 a roll.

I’m sure they’re well intentioned. But I do think we’re spotting a theme here: the people selling us the idea that we have a medical problem often, at the same time, seem to be selling the solution. Pharmaceutical companies promote Night Eating Syndrome and Female Sexual Arousal Disorder, offering Sertraline and Sildenafil to treat them. Patrick Holford reckons that 50% of you have hidden food allergies, or nutritional deficiencies, which he can treat with his books and tablets.

Meanwhile I have nothing to declare but my cheekiness, and if I was very worried about the mobile phone network being a danger to health – which could well turn out to be the case – the first thing I would do is campaign to make my own mobile phone operator erect their mast as close to my house as possible.

Pay attention. The one thing that people who worry about the health risks of mobile phone masts tend to forget is the inverse square law: the power of the signal falls away extremely rapidly as you move away from the mast, much faster than you’d think, exponentially in fact, because the energy is dissipated and spread out in 3 dimensions like a big, ever-growing sphere. A bit like how the skin of a balloon gets thinner, the more you inflate it.

Meanwhile you’re holding a dirty great big transmitter right up next to your brain in the form of your mobile phone. In fact, because of the inverse square law, the phone gives you a far higher dose of evil rays than the mast. Go on, press it harder, I can’t quite hear you. But mobile phones, very cleverly, preserve their battery life by transmitting a much weaker signal into the air (and therefore also your head) when they detect that a mast is very close by. If you have a phone, it’s in your interest to have it transmit at the lowest power it can manage, which means a strong signal from the mast, which means the mast is on your street. I don’t expect you all to start campaigning at once.

Please send your bad science to bad.science@guardian.co.uk


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121 Responses



  1. AitchJay said,

    May 20, 2006 at 5:12 am

    There was a case here of a farmer who carried his mobile in his shirt pocket all day, ended up with breast cancer..

  2. billgibson said,

    May 20, 2006 at 5:47 am

    Any chance of a reference to the published case report? Or do I smell an urban myth?

  3. Ianr said,

    May 20, 2006 at 5:52 am

    According to Cancer research 1 in 130 cases of breast cancer are in males, about 300 cases a year. So I’d say if you are going to get it there is pretty much a 50:50 chance of being on the side you carry your mobile phone,. unless there is evidence to suggest otherwise.

  4. Bob O'H said,

    May 20, 2006 at 7:45 am

    Ben, I think you should start selling your placebos again.

    Bob

  5. megachicken said,

    May 20, 2006 at 7:53 am

    Possibly a bit harsh on Powerwatch. I mean, they do genuinely believe that EMR is bad for you, so it seems fair if they offer a way to protect yourself.

    But the whole undeclared interest thing is rife in Alternative Science. One of the electrosensitivity websites once carried this attack by Michael Meacher on scientists in the pay of big business corrupting the scientific process, particularly when it comes to the safety of GM foods.

    www.i-sis.org.uk/WSoSCYT.php

    Bizarrely, in his essay Meacher forgets to mention that he himself has a conflict of interest; a share holding of “at least” £59,000 in “Planet Organic”, an organic food retailer whose stock value would increase the more he cast doubt on the safety of non-organic foods.

    www.publications.parliament.uk/pa/cm/cmregmem/051214/memi19.htm

    Now I have no doubt that this apparent financial conflict of interest was completely irrelevant. Meacher is genuinely worried about GM foods, and that’s presumably why he invested in those shares. But still, what’s sauce for the goose…

  6. Dave H said,

    May 20, 2006 at 8:42 am

    The inverse square is not exponential.

  7. TimGill said,

    May 20, 2006 at 10:02 am

    Nice job skewering Powerwatch. But what about a sober analysis of the data? Or if that’s too hard, what about telling us what a sober analysis of the data might look like? Prompted by a local campaign, I started looking into this stuff and quickly got tied up in soundbite research, anecdotes, vested interests (and yes, the Government’s billions for selling off the rights to 3G is a biggie) and paranoia. Enough on the bad science already, how about the good science – or isn’t there any?

  8. fh said,

    May 20, 2006 at 10:08 am

    Some problems with your argument here, I think. First, for a non directional antenna, it is an inverse cube not inverse square. But most cell phone towers are quite directional, such as not only to bring them closer to an inverse square but possibly to make the relationship even flatter. Second, you fail to differentiate between occasional cell phone usage and 24/7 exposure from a nearby cell tower. These things are cumulative.

  9. fh said,

    May 20, 2006 at 11:27 am

    While I was writing, TimGill was posting, just above. He’s right. I think “cheekiness” has got the better of usefulness on this one. After all the funds spent on research, are we any closer to understanding the health impacts of mobile telephony? Rather more important issue than whether or not there are snakeoil salesmen cashing in on a fears which even you acknowledge “could well turn out to be” legitimate.

  10. Hector Ballast said,

    May 20, 2006 at 12:22 pm

    According to Dr Grahame Blackwell, there are only SIX known studies purely of the effects of phone masts on people! All show ill-health effects.

    1) Dutch TNO study 2003; effects on wellbeing-headaches, muscle fatigue/pain, dizziness etc from 3G mast

    2) Oberfeld 2004, Spain, found depression, fatigue, sleeping disorder, concentration+cardiovascular problems

    3) Wolf 2004 found fourfold cancer increase within 350m of a phone mast, tenfold among women.

    4) Naila study Germany 2004 found trebled risk of cancer near cellular antenna/masts

    5) Austria 2005, found illness and using EEG, measured immediate changes in brain waves at 80m from mast

    6) Santini 2002; Diverse health effects within 300m of base stations-see below.

    (Reference: www.starweave.com)

    He also says there are no similar studies that found no effects.

    Just thought you would like t’know – in case you’re looking for the science.

    Hector

  11. gwo said,

    May 20, 2006 at 12:42 pm

    As you are someone who comes down heavily on lazy and inaccurate use of precise terminology … can I politely suggest you look up what the word “exponentially” means before using it again?

  12. rueroy said,

    May 20, 2006 at 2:18 pm

    Elizabeth May, a former executive directory of the Sierra Club was on CBC’s the current on Wednesday refuting some nonsense that Paul Watson (ex greenpeace) had been spouting about links between immigration and pollution. Amongst the otherwise sensible things that she was saying, she stated at one point that population growth used to be slow, but in the last 400 years it’s become exponential.

    As regards Ben, I think that his penance should be to calculate exp(-10) to 10 significant figures by hand and compare it to his result for 1/(-10)^2.

  13. JQH said,

    May 20, 2006 at 2:31 pm

    Whatever the merits or otherwise of the idea that phone mast radiation causes cancer and other illnesses, I wonder what sort of tests were done by or on behalf of EMFields to prove their claims about the stopping power of their (very expensive) paint and other products.

    Assuming it has the asserted properties, WHY does it need to be earthed? Ordinary paint blocks visible light without the need for earthing. If anyone from EMFields is reading this, perhaps s/he could explain.

  14. Ade said,

    May 20, 2006 at 5:03 pm

    I am a microwave engineer and Ben is correct as regards the radiation density in any direction dropping off as the inverse of the distance squared. His analogy of the balloon is correct for an isotropic antenna (one that radiates equal power in all directions) but for an antenna that radiates predominantly in one direction then the gain of that antenna increases the power in that direction – the inverse square-law still applies.
    Ben’s explanation of the relative power levels of phones and masts and how they operate is also correct.
    I have attended public inquiries where ‘experts’ have been put up by those who do not want a mast in their locality and heard the twaddle spouted by many of these people, who have their own private agendas.There is a lot of anecdotal evidence and one-off scientific results, non of which have ever been replicated and these are the ones the ‘experts’ quote.
    I can recount events where the mere suggestion that an antenna is radiating has brought on headaches etc. in people.
    A number of scientific enquiries and studies involving large numbers of people including control groups, have been undertaken all of which state that there is no direct causal epidemiological evidence to show that radiation from mobile phone masts or phones is detrimental to the well- being of people.
    A final thought: the use of mobile phones has saved an enormous number of lives owing to the ability to alert the rescue services to emergency situations.

  15. Frank said,

    May 20, 2006 at 5:30 pm

    I’m not impressed by the Starweave site – Hyland’s paper “How Exposure to GSM & TETRA Base-station Radiation can Adversely Affect Humans” is just a short lit review stuffed with unqualified statements such as this:

    “the rates at which the microwaves are emitted in distinct groups of flashes (or pulses) happen to be close to the frequencies of some of the brain’s own electrical and electrochemical rhythms; accordingly, these can be (resonantly) amplified, interfered with (similar to the case of radio reception), and even entrained by the radiation”

    What?! Could I see your numbers on that? No? Oh, well OK. You have a PhD? Hmm. I guess I’ll just have to believe anything you say on trust.

  16. coracle said,

    May 20, 2006 at 5:49 pm

    Just had a quick scan of a review of Hector’s TNO study (www.gr.nl/pdf.php?ID=1042)

    This was in the executive study:

    “Exposure to GSM-900 or GSM-1800 electromagnetic fields had no effect on wellbeing
    in either experimental group. However, upon exposure to a UMTS-like signal, a
    small, but statistically significant increase in the well-being score was observed in both
    groups (a higher score indicates a decrease in well-being). This effect was found after
    only about half an hour’s exposure to what, by everyday standards, was a relatively high
    environmental field strength. In practice, while individuals in the vicinity of operational
    UMTS antennas will be subject to continuous exposure, the field strengths in question
    will be lower. The results of the TNO study cannot be used to assess whether, and to
    what extent, there will be any effect on well-being in people’s day to day environment.”

  17. coracle said,

    May 20, 2006 at 5:49 pm

    summary not study, doh

  18. Frank said,

    May 20, 2006 at 5:54 pm

    Ha – I just remembered, when I was at university there were mobile phone antennae on the roof of our halls. No-one really noticed.

    One day I decided to mock up a “radiation warning” sign, advising people that they were being exposed to increased levels of radiation and to report any adverse effects to the site office. I put 30 oir so round the building. Needless to say, there was a rash of reports of headaches, sleeplessness, and even upset menstrual cycles, particularly from people on the top floor.

    Oh, how I laughed….

  19. sciencefan said,

    May 20, 2006 at 7:55 pm

    I experience a weird feeling when NOT subjected to GSM-1800 radiation. I can’t quite describe it but it’s like feeling that someone (or something?) might be trying to contact me but cannot get through. I suspect that an electromagnetic field of precisely this frequency has a positive effect my the bio-energetic ectoplasm, enabling contact to be established. Are there any studies to back this up?

  20. sciencefan said,

    May 20, 2006 at 7:58 pm

    Not so hot on the typing either when the bio-energetic field is weak:
    “… a positive effect on my bio-energetic ectoplasm …”

  21. Robert Carnegie said,

    May 20, 2006 at 8:12 pm

    I think BT will now sell you a cell phone that isn’t a cell phone when you’re home – except in the sense of having a little cell of your own. But I don’t know what happens if someone dials your cell number then, or perhaps that isn’t how it works.

    How are we doing for scares on computer wireless networking? One of my neighbours has wireless, apparently – my laptop keeps trying to connect to it.

  22. TimGill said,

    May 20, 2006 at 8:26 pm

    Just read Ben’s piece on electromagnetic hypersensitivity from last week and (some of) the exchanges that followed. Phew. I still think it’d be worth trying to shine some light on the evidence. But I’m not about to volunteer.

  23. JQH said,

    May 20, 2006 at 10:44 pm

    Robert Carnegie

    Sue yopur neighbours. You are obviously being irradiated

  24. JQH said,

    May 20, 2006 at 10:45 pm

    and I am obviously pissed

  25. coracle said,

    May 21, 2006 at 2:29 pm

    Robert Carnegie (re wirelss networking),

    I think I’m starting to suffer from EHS, irritability, mood changes, depression after I got my belikin wireless router. No, wait that’s because the bloody thing is crap and keeps dropping my connection. grr. It’s going back to Belkin…

  26. Filias Cupio said,

    May 22, 2006 at 3:10 am

    On radiation drop-off with distance, from an ex-astronomer’s point of view:

    Ben’s use of “exponential” is incorrect, as noted by others.

    fh (post 7) is incorrect about inverse cube – the drop off is inverse square. (S)he is correct that directional antennae can change the drop off curve, to some extent (details below)
    Ade (post 14) says it is always inverse square, even for directional antennae – this is an approximation, correct for a sufficiently large distance.

    Diffraction limits how well you can beam radiation. For an emitter of radius D, emitting at wavelength lambda, you can’t “aim” the radiation to better than an angle of theta=lambda/D (angle measured in radians.) If you’re distance r from the antenna is such that the antenna has an angular size less than theta, you’re (more or less) in inverse square law territory. Any closer, and the drop-off may be slower (or non-existent.) This transition to inverse-square happens at distance about r=D^2/lambda (assuming the antenna design is optimized to beam as efficiently as possible – the transition could occur closer to the antenna.)

    For 1800MHz GSM band, lambda=1/6 metre. Typical cell tower antennae look to me to be about 1m (wild guess alert!), hence you’ve got inverse square if you’re more than about 6 metres from the top of the tower. I.e. Ade (post 14) is correct for practical purposes. (And presumably, as a microwave engineer, knew all this and glossed over these details as being inconsequential.)

  27. Hector Ballast said,

    May 22, 2006 at 11:20 am

    A quick reply to JQH about screening/earthing

    “Whatever the merits or otherwise of the idea that phone mast radiation causes cancer and other illnesses, I wonder what sort of tests were done by or on behalf of EMFields to prove their claims about the stopping power of their (very expensive) paint and other products.”

    Dont know about ECOS (who make the stuff) but Powerwatch say in their lit. that general testing was done by an acousticom microwave meter. If you rent or buy the meter you get a little bit of the screening netting surrounding it. By cutting out the noise, it shows clearly the pulsed microwaves are cut out by the netting.

    There is a version of the meter that gives you a reading. I could only do rough calculations but it the reductions from the screening were at least 90%.

    Powerwatch do say somewhere that a decent aluminium foil is even more effective than the paint. Getting a permanent barrier up using foil is a bit tricky though, whereas the paint is permanent. If bothered by your friendly neighbourhood mast, the foil is worth trying before committing yourself to the big splash, especially if you like playing with sellotape and scissors. You can put posters up with foil on the back and claim you’re not of course a Kylie fan, but its difficult to get decent posters and the reason she’s wall to wall is because microwaves go through gaps and you got a bulk discount…

    Earthing

    “Assuming it has the asserted properties, WHY does it need to be earthed? Ordinary paint blocks visible light without the need for earthing. If anyone from EMFields is reading this, perhaps s/he could explain.”

    The screening is only against microwaves. It screens with or without earthing. As I understand it from their advice, without earthing a magnetic field can build up. One or two others have suggested that earthing improves the screening too – don’t know about this.

    Hector

  28. Hector Ballast said,

    May 22, 2006 at 11:49 am

    Update on earthing – I hope replying to myself doesnt make me go blind.

    The screening paint screens BOTH against microwaves and any bigger electrical fileds from other sources that might happen to be outside your house. Its only in this latter case that earthing is needed. For masts, it isn’t.

    Incidentallty ECOS dont sell earthing equipment. They simply recommend painting carefully on to the earthed tabs that take the screws in your sockets.

    Powerwatch include a cable with similar purpose – its free.

  29. sockatume said,

    May 22, 2006 at 12:11 pm

    How do you earth paint? It boggles my mind.

  30. Delster said,

    May 22, 2006 at 12:13 pm

    Well i had a look at the starweave site and followed through to the study by Dr Hyland and it contained a lot of comments about all the harmfull effects of EM radiation, what it didn’t contain was numbers. There were no study refrences, nothing on his studies from methodology through results etc just a simple condemnation of EM radiation.

    www.emrnetwork.org/position/hyland_base_station_talk.pdf is the location.

    Also i googled him and apparently humans emit coherent radiation (as in laser) link here www.vanderbilt.edu/radsafe/9907/msg00344.html

    have to admit i didn’t read it as it’s a bit jumbled on that site and work intrudes again.

  31. superburger said,

    May 22, 2006 at 12:27 pm

    When the TV / Radio network was first constructed in the UK was there a similar panic about dangerous electromagnetic radiation frying people’s brains? Or is this fear of transmitters a new thing?

    I suspect people hear ‘microwave’ and link it to the microwave in their kitchen (just look at the damage it can do to an overbaked potato) and come to the conclusion that it does the same thing to their brains.

    radio waves sound a lot nicer (happy Mail reading families gathered round the wireless, in a sepia Conservative britain without asylum seekers and gypsies threatning house prices etc) so must be safer.

    As an aside the technique of MRI (magnetic resonance imaging) is much more accuratley called NMR (nuclear magnetic resonance) but when the switch was made from NMR being a lab technique for chemists / biochemists into a medical technique it was feared that people would be put off by the ‘nuclear’ part (3 mi island, chernobyl etc) and magnetic was much gentler sounding.

    My head hurts after an hour on the mobile to the girlfriend, so maybe there is something in this mobile phone stuff after all…….

  32. Michael Harman said,

    May 22, 2006 at 12:31 pm

    I’ve had a quick look at the first Hyland site in Delster’s post (no 31), and it seems that the main danger is to brain electrical activity and brain cells. So the answer is simple – bring on the aluminium foil hats! That will also have the advantage that the rest of us will immediately be able to identify the shielded ones.

  33. Hector Ballast said,

    May 22, 2006 at 1:42 pm

    sockatume

    “How do you earth paint? It boggles my mind. ”

    The paint is nickel-based. Not obvious from the article or the discussion!

  34. JQH said,

    May 22, 2006 at 2:09 pm

    Hector Ballast

    Just because the paint is nickle based does not mean it will conduct electricity.

    The bit about a magnetic field building up without earthing sounds compete b******s to me.

  35. Delster said,

    May 22, 2006 at 2:40 pm

    you could get a static electrical charge build up on something but i’ve personally never seen a house rubbing itself on a piece of amber before…. although i have seen a cat rubbing itself on a house!

    Having said that most houses contain water pipes…. which make incredibly good earthing connections in themselves so i can see it happening myself… although maybe with enough cats…….

  36. Delster said,

    May 22, 2006 at 2:41 pm

    sorry…. that last piece shoud have said i CAN’T see it etc

  37. Aspiring Pedant said,

    May 22, 2006 at 3:18 pm

    I believe this is conductive carbon (graphite) paint similar to that used for grounding specimens for scanning electron microscopy or to coat cardboard cartons for “Electro-static discharge safe” packing for sensitive Integrated circuits.
    Walls painted with this are presumably conductive and earthing is necessary to protect against stray voltages or the effects of lighting strikes etc. Just as would be necessary for metal walls.
    I don’t suppose the cold water and hot water pipes (& various other things) in my bathroom are likely to be at different potential but I notice they are electrically bonded just in case.

  38. luvaduck said,

    May 22, 2006 at 4:07 pm

    I’m not fully conversant with the domestic electrical wiring regulations, but I suspect if you use electrically conductive paint on the walls of a kitchen or bathroom it would need to bonded to the water pipes in any case.

  39. sockatume said,

    May 22, 2006 at 4:14 pm

    Even if the paint’s nickel-based, it’s not necessarilly conductive. Carbon’s the best bet, but then you have to overpaint this graphite surface if you don’t want grey walls.

  40. Hector Ballast said,

    May 22, 2006 at 4:29 pm

    its not necessarily conductive..but it is…30% nickel

  41. Aspiring Pedant said,

    May 22, 2006 at 4:35 pm

    Sockatume – that’s exactly what emfields recommend.

    www.emfields.org/screening/paint.asp

  42. Hector Ballast said,

    May 22, 2006 at 4:37 pm

    JVQ

    “The bit about a magnetic field building up without earthing sounds compete b******s to me. ”

    Er

    “Ordinary paint blocks visible light without the need for earthing. If anyone from EMFields is reading this, perhaps s/he could explain. ”

    The b******s was already in the question.

  43. hairnet said,

    May 22, 2006 at 4:46 pm

    The earthing would be necessary to prevent a large build up of charge on the wall so painted. The earhting would maintain zero potential between the wall and earth, a safer situation.

  44. Andy said,

    May 22, 2006 at 5:23 pm

    >30dB of attenuation from 900MHz to 18GHz with a single coat of paint?
    Do the advertising standards rules apply to online claims because that would be interesting to see proved.

  45. Andy said,

    May 22, 2006 at 5:48 pm

    At the risk of replying to Hector:

    RF shielding works by shorting out the electric field that is part of the electromagnetic wave. In other words it needs to be conductive to work. 30% Ni in something that is probably carbon loaded is going to give you a reasonable conductivity but not stunning. I doubt it would be enough for the 30dB of attenuation claimed (30dB attenuation = 3 orders of magnitude decrease = a 99.9% reduction)

    Aluminium foil is very effective shielding at high frequencies. Down at 900MHz it should still work fairly well but I doubt you could get 30dB of attenuation from a metal layer that thin.
    The real problem with foil is joining sheets. Simple overlapping will give you a reasonable join but a long way short of the levels of shielding we are aiming for here. Some copper tape with conductive adhesive works fairly well at low frequencies but is expensive and for the higher frequencies I’ve normally had to resort to soldering along the join to obtain good shielding.

    Also without good design or grounding of your shielding you can often create resonances and make the problem worse.
    While very tongue in cheek this paper is a good illustration of how poorly executed shielding can end up boosting signals rather than decreasing them.
    Also as a side note, that paper also gives you an idea on the sort of equipment what would be required to verify the claims on that paint. No self respecting RF lab would touch a hand held meter for this sort of measurement.

  46. Hector Ballast said,

    May 22, 2006 at 10:28 pm

    Andy

    “>30dB of attenuation from 900MHz to 18GHz with a single coat of paint?”

    Andy it clearly states two coats of the paint are required.

    Two foil sheets also appear to shield better..its still cheaper and no supermarket is raising hysterical fears to sell tinfoil.

    “No self respecting RF lab would touch a hand held meter for this sort of measurement.”

    True – that’s why no-one did. Powerwatch said they’d done some sort of test with the hand meter – but they didn’t make a 99.9% claim at all:

    “Two coats stop about 98% of the incoming microwave radiation”.

    ECOS say “up to 99%”.

    The “advertising standards” authority would ask you why you didn’t read any of the information that you were complaining about.

    “Also without good design or grounding of your shielding you can often create resonances and make the problem worse.”

    What’s this – next weeks Bad Science column – why don’t you put this to ecos paints. A minute ago it was why the earthing.

    Hector

  47. JQH said,

    May 23, 2006 at 7:52 am

    Hector

    Its JQH not JVQ.

    If the question is b******s perhaps you could explain why

  48. sockatume said,

    May 23, 2006 at 8:45 am

    Funnily enough the family of a friend have a Faraday cage computer room in part of their barn conversion (as a precaution against electrical storms). Just a case of hooking all the plasterboard backing together and earthing it to the water pipes with some wire. Completely kills mobile phone reception, and explained why they couldn’t get their wireless network to work. Much cheaper than carbon-based paint.

    They’ve been told that they need to buy unbalanced magnets due to a negative ley line, though, so I don’t know how that’s going to affect the electromagnetic properties of their conversion.

  49. Hector Ballast said,

    May 23, 2006 at 8:54 am

    JQH – apols for name error

    You tell me – what electric field might be a concern from visible light and paint. Could be the new Dulux marketing angle?

  50. Aspiring Pedant said,

    May 23, 2006 at 8:55 am

    Andy,

    What you say is correct.

    From – www.emfields.org/screening/overview.asp

    “Also available from us, carbon screening paint. One coat of this specialist paint stops over 99.9% of incoming radiation (900 MHz – 18,000 MHz).”

    Impressive stuff but then at £50.99 per litre you’d expect something pretty special.

  51. Hector Ballast said,

    May 23, 2006 at 9:02 am

    Socka

    “Funnily enough the family of a friend have a Faraday cage computer room in part of their barn conversion (as a precaution against electrical storms). Just a case of hooking all the plasterboard backing together and earthing it to the water pipes with some wire. Completely kills mobile phone reception, and explained why they couldn’t get their wireless network to work. Much cheaper than carbon-based paint.”

    Interesting – though is killing the phone reception the same as stopping the signals? I dont know about telecoms but say your imaginary problem was EMF from communicati0on with your printer. Disrupting the key protocols (a handshake signal here and there!?) would be enough for the communication to be killed, in the sense the printer wouldn”t respond.

  52. Caspar said,

    May 23, 2006 at 9:05 am

    Thanks to comments so far for which seem to have attempted to add to knowledge – perhaps including but not necessarily limited to posts nos. 14, 16(?) and 26.

    There are proposals for a new mast in my neighbourhood, and quite a few people are organising against it. My first reaction is that their fears are overblown or irrational. But I am barely on the verge of technical literacy.

    Can someone put some numbers on this in a way that would help in a public discussion for non-specialists? So, for example, what would be the relative exposure to electromagnetic signals arising from mobile telephony from a) a “standard” (typical urban area) mast at five hundred metres for 24 hours a day ; b) a “standard” (typical urban area) mast at one hundred metres for 24 hours a day; and c) a typical mobile phone for at 1cm for one and two hours per day? Also what other electromagnetic signals of what strength would a typical individual in a normal UK urban area usually be exposed to in a 24 hour period.

    Someone else may think of more useful ways of framing these sorts of questions, and more realistic parameters, but I hope the general point is made.

  53. JQH said,

    May 23, 2006 at 10:13 am

    Hector – the point I was making is that if visible light – which is far more energetic than microwaves – does not produce an electrical field, why should microwaves?

    Seems to me that covering your house with anything that is opaque to microwaves will work just as well as this expensive nickle based stuff.

  54. JQH said,

    May 23, 2006 at 10:59 am

    j

    Presumaby. But then if you’re that concerned about about microwaves you don’t have a mobile phone or a computer.

    Hang on. If that’s the case, how are they putting up websites and posting on the net? There’s a flaw in the thinking somewhere….

  55. Hector Ballast said,

    May 23, 2006 at 11:02 am

    j – Probably right – might be possible with an ariel – but really, anybody who pays hundreds of pounds to block mast signals and then tries to use a mobile in their house wants their head irradiated. Guests might conceivably want their own connection – personally I’d tell them to get an ariel they just need to touch the paint while I “earthed” the paint to the mains.

    JQH

    Confusion alert – The paint is for 2 types of screening, for microwaves earthing not nec. The earthing is for when there is an OUTSIDE electric field, to prevent the buildup of a magnetic field INSIDE

    I understand very little is opaque to microwaves even quite conductive material.

  56. Robert Carnegie said,

    May 23, 2006 at 12:59 pm

    I tried putting a personal cassette player that was susceptible to cell phone interference (went bzzz near to cell masts) in a metal box. Didn’t help. Then when I wanted something to keep my own phone in, a metal spectacle case seemed to cut it off from connecting. It’s a funny game, isn’t it?

    I suppose this makes Hector’s point – or maybe it’s just that the signal couldn’t get /out/ – although another could be that (if someone will check my figures) the difference between cooking in a microwave oven and carrying a microwave cell phone is like the difference between being hit by a car travelling at 30mph and continental drift. But England is going to sink, you know, ha ha ha (I’m in Scotland).

  57. JQH said,

    May 23, 2006 at 1:08 pm

    Hector

    Aren’t the casings of microwave ovens opaque to microwaves? Otherwise people using them would cook themselves.

    I’ll have to find the time to play with our microwave generator and see if I can find anything that is opaque

  58. amoebic vodka said,

    May 23, 2006 at 1:20 pm

    The dangers of misjudging how effective a faraday cage is – never assume it is sufficient to block a radio mic connecting to its receiver when going to the toilet.

  59. Hector Ballast said,

    May 23, 2006 at 1:37 pm

    JQH said

    “Aren’t the casings of microwave ovens opaque to microwaves? Otherwise people using them would cook themselves.”

    Yes – except when they leak. In a carefully controlled scientific experiment where I was the lead scientist, both of them leaked like mad.

  60. Andy said,

    May 23, 2006 at 5:08 pm

    Never trust a faraday cage. They are never perfect. I’ve had my cell phone ring inside a screen room with walls of solid metal and a conductive seal around the door.
    All they ever do is decrease the signal, they will never block it.

    One rather weird thing about faraday cages: They are good at stopping RF noise from getting in but not nearnly as good at stopping it getting out.
    e.g. Take this simple test. Put an RF transmitter and an antenna a fix distance apart. Place a faraday cage over the receiver and measured the received energy.
    Now move the same faraday cage so that it is around the transmitter and measure the energy at the receiver.
    Common sense would tell you that you would get the same or at least very similar measurments both ways around. You have the same transmitted energy, the same shielding and the same distance. You are going to get the same result aren’t you? Common sense is of course wrong. Far more energy from the transmitter will reach the receiver when the cage is over the transmitter than when it is over the receiver.

    As soon as you put some RF absorber on the inside of the cage then you will start to see the similar results both ways around.

    What does this mean in the real world?
    That if you measure say the microwave leakage from a microwave oven you will get very different results if the oven is empty than you will if these is something in the oven to absorb the microwaves (e.g. some food).

    Hector: In the experiment where you were lead scientist did you test the ovens both with and without any food / a glass of water inside? Theory says that you should see a significant difference in the results, it would be interesting to see what the real world effect is.

    Obviously the theory also indicates that any health risk measurments taken with the ovens empty is invalid since that is not how people run them in the real world.

  61. Andy said,

    May 23, 2006 at 5:35 pm

    Hector Ballast said (comment 45):

    ——
    Andy

    “>30dB of attenuation from 900MHz to 18GHz with a single coat of paint?”

    Andy it clearly states two coats of the paint are required.
    [...snip...]
    The “advertising standards” authority would ask you why you didn’t read any of the information that you were complaining about.

    ——

    I refer you to www.emfields.org/screening/overview.asp:

    “Carbon Screening Paint

    Also available from us, carbon screening paint. One coat of this specialist paint stops over 99.9% of incoming radiation (900 MHz – 18,000 MHz). The paint is easy to apply and is water soluble. It is available in 1 litre and 5 litre tins.”

    I never stated who was claiming the effectiveness or the number of coats. However since I mentioned advertising standards the most obvious place to check are the claims made by the person selling the paint and the most ovbious retailer is the one mentioned in the main story. The claims that a retailer must be held to are the ones which they make, not those of a reviewer or the manufacturer of the product.

    Back to your post:
    ——
    [quoting me] “Also without good design or grounding of your shielding you can often create resonances and make the problem worse.”

    What’s this – next weeks Bad Science column – why don’t you put this to ecos paints. A minute ago it was why the earthing.
    ——

    I’m sure Ben can find something more interesting to write about than some of the problems facing RF engineers when they try to design good shielding.
    What would you like me to ask ecos paints? something like:
    “Dear sir,
    Is it possible that if used incorrectly your products would make it possible to create a resonant cavity that actually amplified the RF energy at certain frequency bands?”

    An answer of yes to that question would be perfectly reasonable. In fact the more effective their products are the more likely an answer of yes becomes.

    I was simply pointing out that RF shielding is a non-trivial matter whether you attempt to do it using paint, foil or inch thick metal plating and that there are complexities that can be virtually impossible to predict.

  62. jasont said,

    May 23, 2006 at 7:37 pm

    This is a very serious problem and you ought not to mock the afflicted. I have suffered over many years and am only now coming to realise the true source of my problems.

    Electromagnetic Fields, tragically, are now part of everyday life. This is caused by the artificial current (AC) that surrounds us every day. Magnetic Fields are more common in the home than electrical currents, any plug or wire carrying a current produces an electromagnetic field. This AC is different from the Earth’s current and the current it produces causes adverse effects in our bodies at a cellular level. Experts, such as the late Dr Neil Cherry, believe that our cells expend more energy to protect themselves from these fields. This drains our energy and leads to fatigue.
    By protecting ourselves from EMF we can become more tuned into the Direct Current (DC) which is beneficial to us and protects against negative influences.
    This is to say nothing of the damage done to the blood brain barrier by emfs.

    Aspiring Pedant (it’s a pretty sad aspiration in opinion) you may mock but £50.99 a litre for carbon paint is a small price to pay for piece of mind and I expect to be able to fully protect my bedroom for less than £500.

  63. j said,

    May 23, 2006 at 8:18 pm

    “J –No, your mobile phone wouldn’t work but I suppose you could have wireless networking internally. You’d need an external aerial for radio reception.”

    Fair enough…wonder how it’d effect the neighbours if you had flats below ;)

  64. ayupmeduck said,

    May 23, 2006 at 8:35 pm

    Jasont, I’m sorry that you have, or at least believe that you have, this affliction. Most of the comments here are constructive and are trying to understand if the claims for the paint can have any merit at all – I think you will find that they have very little merit.

    Meanwhile I have some questions for you: What is the source of this beneficial DC that you refer to? How do we “tune into” it? And how does it protect against negative influences? Indeed, what negative influences are you refering to?

  65. Andy said,

    May 23, 2006 at 8:54 pm

    Jasont:

    On a point of clarity: Using AC to indicate artificial currents is going to get very confusing. In electrical terms AC is normally used to indicate Alternating Current.

    My apologies if this is all repeating stuff you already know but I just want to make sure we are all using the same terminology.

    An AC (alternating current) system is one where the potential between the two wires is constantly changing. Normally this is as a sine wave from plus the maximum voltage to minus the maximum voltage relative to some constant or neutral wire. This creates a constantly changing current which reverses direction at the same period as the voltage on the wires.

    A DC (direct current) system is one where there is a constant potential between the two wires. Assuming there is a constant load on the system the current will remain constant.

    Any and all electrical currents will produce a magnetic field that is proportional to the current flow. This means that a DC current will produce a constant but static magnetic field while an AC current will produce a constantly changing magnetic field.

    Since a pure DC signal is static it can not carry any information. Just about any electrical signal that is carrying any information (as opposed to ones used purely to supply power e.g. the mains into your house (50Hz 240V AC) or a battery (DC)) will contain both a DC and an AC component.
    e.g. most electronics uses 0V and 3.3V to indicate digital data. Assuming the data on the line is around random then this can be split into a DC current of about 1.65V combined with an AC signal also of 1.65V. If the data has a non-random bias then these numbers will change but it will always be possible to split it into these two components.

    This holds true for just about any complex electrical system be it man made or natural.
    The relative magnitudes of the DC and the AC signals and the frequencies of the AC components may be very different between natural and man made signals but to make the blanket statement that AC is artificial and that DC is natural is incorrect.

  66. Hector Ballast said,

    May 23, 2006 at 9:50 pm

    Fyse

    “Mr Ballast, what do you do for a living, and what is your scientific background? In what context was this experiment on microwaves conducted?”

    Had I any vested interest I would reveal it. I would of course reveal any expertise or qualification necessary to support any scientific judgements that I make, should I make any.

    But I thought I’d given enough of a clue to the tongue in cheek by saying ‘both’ ovens leaked. No real science was necessary. The microwave ovens leaked because the acousticom monitor repeatedly went nuts when they were switched on. The leaks were probably not at anything resembling full power, or my brains may have been ‘fried’ as suggested (how could I tell, I hear you ask). Maybe they leak down to something like the level of a mobile phone. I didn’t have a measuring device then. The ovens did contain water as it happens, but they shouldn’t leak regardless.

  67. Michael Harman said,

    May 23, 2006 at 10:24 pm

    Fyse said “You may not believe us, but our interest in the subject is out of concern for the sufferers themselves. Until the cause is conclusively proven the appropriate treatment cannot be known, and people will continue to sufferer these genuine and highly distressing symptoms.”

    That seems to echo a remark I’ve just come across by Edvard Ernst, professor of complementary medicine at Exeter: “My allegiance is firstly to the patient … and secondly to science.” (education.guardian.co.uk/academicexperts/story/0,1392,1048903,00.html)

    But I myself don’t want to appear too saintly. Personally, my primary allegiance is to science. I’m interested in seeing how far the patient side of this matter is based on sound science, and what the scientific uncertainties are. But secondarily, I don’t want to show any disrespect to the patients.

    And from that point of view, I wholeheartedly agree with Fyse, that until the cause is conclusively proven (I would say “adequately understood”), the appropriate treatment cannot be known.

  68. Robert Carnegie said,

    May 23, 2006 at 11:08 pm

    Re my tape player picking up buzz from cell towers – as you suppose, I was indeed using earphones, but the same earphones with another tape player or other device in the same locations didn’t have the noise.

    Now as far as microwave ovens with nothing to cook are concerned (micros also interfere with my personal listening equipment, as does my DECT phone), instructions warn against operating an empty microwave oven, but I was led to understand that the waves still don’t leak out particularly (it must be a common mistake), they just bounce back into the emitter and heat it up instead of heating anything else, and this is liable considerably to shorten the appliance’s service life.

    I was interested to note that the electric power (watts) used by a microwave oven is substantially higher than the microwave power rating. I presume that watts are watts but the excess is the waste heat that the machine also generates.

    I once spent some time looking for a safe detector for microwaves inside the oven, because I had a wonky door and sometimes it did everything except for actually transmitting microwaves. I had in mind a lamp that would light up under microwaves – I wondered if a xenon bulb would do that – or any other visible indicator that would not, of course, contaminate my food. For instance, an electric spark seemed like not a good idea – don’t you get ammonia or ozone or something from that? In the end I gave up and scrapped the oven for a new one.

  69. tomh said,

    May 23, 2006 at 11:20 pm

    hector, if microwave ovens were leaking/radiating em radiation outside of the microwave oven, AND that radiation was the correct frequency to exite water molecules (is that correct), then I would be extreamly worried, but if its just radiating some radio frequency / most other frequency radiation, then theres nothing to worrey about (if it started radiating hard x-rays / gamma rays, I might also be a *tad* conserned, well very actually but the risk probably wouldnt be that high even then)

  70. tomh said,

    May 23, 2006 at 11:30 pm

    #just becuse we’ve got on to microwave ovens, here are some useful links about them
    home.howstuffworks.com/microwave1.htm or en.wikipedia.org/wiki/Microwave_oven for a longer overview.

  71. Andy said,

    May 23, 2006 at 11:31 pm

    Microwaves must leak. It is theoretically impossible to build one that doesn’t.

    If I have a perfect faraday cage with a charge outside of it then I can not detect that charge from within the cage.
    However one of the upshots of Gauss’s Law is that if I have a perfect faraday cage containing an electrical charge then the outside world can still detect that charge but can not tell where it is within the cage. Since an RF source is basically a modulated charge then this too can be detected from the outside.

    Alternatively think of it like this:
    If a microwave oven did not leak any energy then when you switch it on with no RF absorbing material inside where would the energy go? You are pumping up a couple of hundred watts of energy into a box which in theory will reflect internally but not absorb it. That energy has to go somewhere, without an absorber inside the oven the only place it can go is out. Well unless you want to oven to explode.

    Secondly no faraday cage is ever perfect unless you happen to have a seamless, hollow block of superconductor. And then it would be rather expensive and a little tricky to get food in and out of.

    Microwaves do, must and will always leak. If this worries you then avoid them but don’t blame a manufacturer because they failed to breaking the laws of physics.

    Feel free to criticise them for how much they leak. However some form of more quantitative measurement other than a monitor going nuts is required to justify those criticisms.

  72. Andy said,

    May 23, 2006 at 11:55 pm

    tomh

    Yes the radiation leakage from a microwave oven will be predominantly at the microwave frequency that is used to cook food. However the magnitude of the leakage is such that it is not a meaningful health risk.
    Also remember that the inverse square rule applies, the intensity of the radiation will drop very rapidly as you move away from the oven.

    That said there are very good reasons why microwave ovens warn against using them if there is any damage to the door or the door switch and to not interfere with the door open/closed detection. Either of those could cause genuine safety hazards.

    Personally I don’t think that a well maintained microwave is a meaningful health risk but if you want to further cut down on the risk/exposure then you can take a couple of basic steps:
    1) Angle the microwave such that the door is facing away from any area with people nearby (the bulk of radiation leakage is from the door and the door seal).
    2) Place it further away from where you will be while it is in use (again the inverse square law, double the distance and you have 1/4 of the energy).

    Having said all that I use the most effective method of all. I don’t own a microwave. Not because of any health reasons but because I prefer food that’s cooked rather than heated.

  73. Hector Ballast said,

    May 23, 2006 at 11:56 pm

    The wikipedia link says microwaves transmit at 2450 MHz. Isnt 3G mast frequency 2100 MHz. But surely the power level of the leak is the concern not the freq. It can’t be anywhere near the level inside but that leaves a large range where it could potentially do damage without heating your body tissue. It not exactly reassuring that they leak at all.

  74. Hector Ballast said,

    May 24, 2006 at 12:23 am

    Andy

    “Feel free to criticise them for how much they leak. However some form of more quantitative measurement other than a monitor going nuts is required to justify those criticisms. ”

    Why so defensive… I was only pointing out the fact that they do leak. Should I have kept the results of my pioneering experiment to myself? Bad Science, that is

    And what was this anyway..
    “Obviously the theory also indicates that any health risk measurments taken with the ovens empty is invalid since that is not how people run them in the real world. ”

    Do you know somethign we don’t!? If there were a ‘health risk mearurement’ for an empty oven, there would presumably exist an amount of food/water which constitutes the boundary between health risk and no health risk. Great for putting on the label, along with the fact that the machine leaks but only due to physics…not criticising, you understand…

  75. pv said,

    May 24, 2006 at 12:44 am

    Hector, the channel tunnel leaks too and one could concievably construct a scenario where that might be a health hazzard. It’s a “potential” risk and should be inscribed in ten-foot high letters above the entrance at each end. Don’t disembark in the tunnel and lie face down in a puddle.

  76. ACH said,

    May 24, 2006 at 8:39 am

    quote: This is to say nothing of the damage done to the blood brain barrier by emfs. end quote

    Jasont, could you explain this to me please? I was pretty bad at A level physics, so a lot of this emf stuff is beyond me.

    However, drug delivery through the BBB is a particlarly tricky problem, and if emf damages or disrupts the BBB, this could possibly be exploited beneficially.

  77. Hector Ballast said,

    May 24, 2006 at 9:30 am

    Andy

    Liked the fatuous comparison made by ACH with the Channel tunnel. Nothing is dangerous! Unfortunately you also tap into thinking this when you say “As I am sure you know there is no hard and fast dividing line between a safe level and an unsafe level of anything.”.

    Microwaves known to cook flesh in a minute should not be equated with “anything”.

    Dont overstate my observations. Theres no research paper coming out. I’m a human being, arguably, and I noticed that microwaves leak. I don’t know whether they create a significant health risk or not. “Leak like mad” is a reasonable description of a leak that showed up everywhere in the room and that was the loudest noise I’d heard on the microwave monitor. I stated I had no quantititaive reading. I made no health claims though if anything I’d be more concerned at your alarmed responses. I stated my view – as people’s brains aren’t often going up in smoke near microwaves, the levels are probably comparable to standing next to a mobile or cordless.

    But since you say “of course they leak – its science”, I would be more convinced by your assurances if they were based on knowledge of the level of the leak which must therefore be an open secret among manufacturers.

    “I apologise of the use of the phrase “health risk measurement”, it is poor phrasing.
    I was trying to state that any experiments that aim to quantify the RF leakage from microwave ovens in order to ascertain whether it is of a sufficient level to be a possible risk to human health should be undertaken under more normal use situations and not under environments which violate the manufactures instructions and which could theoretically result in artificially high results.
    Better?”

    Yes but get ready to explain to people not to have accidents like putting in the wrong number into the timer or forgetting to put in the food/water, and that actually such slips expose them to a level of microwaves not necessarily safe. Trouble is, that would obviously tell them about the leaking and they might not buy the product.

    Hector

  78. coracle said,

    May 24, 2006 at 10:37 am

    ACH,

    after a quick search there is only one article on the bbb and emf effects (conclusion is no effect). Abstract and ref below.

    Unique Identifier 15922049

    Authors Cosquer B. Vasconcelos AP. Frohlich J. Cassel JC.

    Authors Full Name Cosquer, Brigitte. Vasconcelos, Anne Pereira de. Frohlich, Jurg. Cassel, Jean-Christophe.

    Institution LN2C UMR 7521 Universite Louis Pasteur, CNRS, Institut Federeratif de Recherche 37, GDR CNRS 2905, 12 rue Goethe, F67000 Strasbourg, France.

    Title Blood-brain barrier and electromagnetic fields: effects of scopolamine methylbromide on working memory after whole-body exposure to 2.45 GHz microwaves in rats.

    Source Behavioural Brain Research. 161(2):229-37, 2005 Jun 20.

    Abstract We first verified that our 12-arm radial maze test enabled demonstration of memory deficits in rats treated with the muscarinic antagonist scopolamine hydrobromide (0.5mg/kg, i.p.). We then investigated whether a systemically-injected quaternary-ammonium derivate of this antagonist (scopolamine methylbromide; MBR), which poorly crosses the blood-brain barrier (BBB), altered maze performance after a 45-min exposure to 2.45 GHz electromagnetic field (EMF; 2 micros pulse width, 500 pps, whole-body specific energy absorption rate [SAR] of 2.0 W/kg, +/-2dB and brain averaged SAR of 3.0 W/kg, +/-3 dB); if observed, such an alteration would reflect changes in BBB permeability. The drug was injected before or after exposure. Controls were naive rats (no experience of the exposure device) and sham-exposed rats (experience of the exposure device without microwaves). In a final approach, rats were subjected to i.v. injections of Evans blue, a dye binding serum albumin, before or after EMF exposure. Whether scopolamine MBR was injected before or after exposure, the exposed rats did not perform differently from their naive or sham-exposed counterparts. Thus, EMFs most probably failed to disrupt the BBB. This conclusion was further supported by the absence of Evans blue extravasation into the brain parenchyma of our exposed rats.

  79. j said,

    May 24, 2006 at 11:30 am

    “Why so defensive… I was only pointing out the fact that they do leak. Should I have kept the results of my pioneering experiment to myself? Bad Science, that is”

    “But since you say “of course they leak – its science”, I would be more convinced by your assurances if they were based on knowledge of the level of the leak which must therefore be an open secret among manufacturers.”

    Can I ask how long ago you did your ‘pioneering’ experiment – just it’s been known for quite a while that microwaves leak to an extent (for example, the extent of leakage is regulated by the FDA www.hps.org/hpspublications/articles/microwaveoven.html)

    Also, I don’t think it’s much of a secret – there’s info on, for example, the regulation of microwave oven leakage which is available in the public domain. Probably the reason we don’t hear much about it is that – so long as this leakage is kept within safe limits – most people aren’t sufficiently interested in microwave ovens to care.

    That doesn’t mean, of course, that there’s anything wrong with being interested in the details of how microwave ovens work/leak. I don’t think there’s much of a secret about this, though – more disinterest, probably…

  80. sockatume said,

    May 24, 2006 at 12:10 pm

    If anyone’s still interested: they didn’t invest in those unbalanced magnets.

  81. Michael Harman said,

    May 24, 2006 at 12:46 pm

    Glad to hear they weren’t too unbalanced!

  82. hairnet said,

    May 24, 2006 at 1:04 pm

    Sorry hector but are you showing concern for microwaves or radio waves “quantify the RF leakage from microwave ovens” RF usually means Radio Frequency which is an order of magnitude lower than microwave. Not that radio, microwave , infra red etc have any meaning themselves, wavelength and frequency are the usefull terms to use.

  83. pv said,

    May 24, 2006 at 1:05 pm

    Hector, twas I (pv) wot rote fatuous comment about channel tunnel, not AHC.
    Except that I didn’t think it was fatuous at all. It isn’t a secret that microwave ovens leak, any more than it has ever been a secret that the channel tunnel leaks. The tunnel was constructed that way. It’s just that many people seem to be unaware of these things. When they do find out, not unusually from a scaremongering press, they often conclude that someone has been hiding something from them. They blame their ignorance on corporate or government secrecy (how exciting and myserious!!) rather than their own hitherto lack of interest and the fact they are being manipulated by their informer.
    What is fatuous is your inference from my comment that “nothing is dangerous”. Life is dangerous, Hector, and so is scaremongering.

  84. Hector Ballast said,

    May 24, 2006 at 4:00 pm

    To Hairnet

    I’m only talking about microwaves, others brought in RF.

    JQH had earlier asked

    “Aren’t the casings of microwave ovens opaque to microwaves? Otherwise people using them would cook themselves.”

    And I had replied

    “Yes – except when they leak. In a carefully controlled scientific experiment where I was the lead scientist, both of them leaked like mad.”

    Wasn’t claiming to have invented the wheel, you know.

    Now to pv. (apols. to ACH)

    It might help if you lot got your story straight. Either they leak or they don’t. Its not scaremongering to say they do when someone says they don’t. Neither does this constitute a health claim or scare.

    Simple, really. Just like this

    “Hector, the channel tunnel leaks too and one could concievably construct a scenario where that might be a health hazzard.”

    While my description may have been unkind, your statement changes the subject (microwaves), to leaks of water, and implies no cause for concern without consideration of the subject. A clever use of duff logic, then.

  85. Andy said,

    May 24, 2006 at 4:32 pm

    Hector.

    Please don’t put words in my mouth.
    To quote from your post:
    ————-
    ‘But since you say “of course they leak – its science”,’
    ————-

    A very quick search of this board indicates that I never said those words. Yes I said something very similar however your use of quotation marks indicates that you are making a direct quote. That is both untrue and misleading, please don’t do it again.

    Now on to the actual content of your post:
    ———-
    “Liked the fatuous comparison made by ACH with the Channel tunnel. Nothing is dangerous! Unfortunately you also tap into thinking this when you say “As I am sure you know there is no hard and fast dividing line between a safe level and an unsafe level of anything.”.

    Microwaves known to cook flesh in a minute should not be equated with “anything”. ”
    ———-

    One photon at 2.45GHz per hours is totally safe. I don’t think anyone is going to ever disagree with that.
    I am using totally safe to mean that the health risks involved are at a far lower level than anything else (.e.g. breathing) and so at a point at which they are statistically meaningless and impossible to measure.
    1GW of RF energy at 2.45GHz for an hour is not safe.
    By not safe I mean that statistically you are very very dead to the point where probability of survival is meaningless and too low to measure.

    Somewhere in between there is an exposure level at which a meaningful percentage of people will have health issues.

    You are almost correct: Microwaves _at an intensity_ known to cook flesh in a minute should not be equated with “anything”.

    I haven’t measured the level of the leaks myself but people have already linked to pages giving the legal maximums. It is not an open secret how much they leak by. It is open.

    Personally those numbers strike me as very low. You may disagree but you should check what you are disagreeing with first.

    ————-
    “Yes but get ready to explain to people not to have accidents like putting in the wrong number into the timer or forgetting to put in the food/water, and that actually such slips expose them to a level of microwaves not necessarily safe. Trouble is, that would obviously tell them about the leaking and they might not buy the product.”
    ————

    Have you considered a career in marketing?
    They already tell you not to do those things. How about actually measuring the numbers first before adding ‘or you’ll melt your brain’ to the end of the warning?
    As I have said a number of times I do not know the figures involved. It may be a 1% increase, it may be a 10% increase, it may be a 1000% increase. I have no idea and have never claimed to know. They may even have some safety cut off for those situations.

    All I said was that theory would indicate that they should leak more when empty and when wishing to measure how much radiation people will be exposed to under normal everyday use of a microwave oven you must test the leakage under normal everyday use.

  86. jasont said,

    May 24, 2006 at 4:51 pm

    Andy,
    Yes – AC for artificial current is a poor description for the phenomenon that interests me. I apologise – I confess I am not a scientist or even a doctor but you probably guessed that much anyway.

    The earth’s atmosphere carries a charge, a current, a voltage, and naturally occurring electromagnetic waves. These Telluric currents move equator-ward (daytime) and pole-ward (nighttime). The field varies in time and over the frequency range 0.001 to 5 Hz. Extremely Low Frequency – ELF.

    Dr Cherry published research in the Natural Hazards journal, Cherry (2002), which shows that a natural electromagnetic signal, called the Schumann Resonances, generated by a tropical thunderstorms, and radiating around the world in the resonant cavity created between earth’s surface and the bottom layer of the ionosphere, is resonantly absorbed, detected and responded to by the brain because of the ELF frequency matching the frequency range of the spectrum of the brain EEG rhythms.

    This natural emf is believed by some commentators to be beneficial while man made emf is harmful. I’m not sure why and there may be a few quacks & charlatans about who would seek to exploit the lack of scientific understanding of myself and others like me – I found this quite charming:-
    www.blockemf.com/

    ACH,

    I’m afraid I don’t know how the blood brain barrier is opened by microwaves but there has been a lot of research done on this and many, but certainly not all, have reported negative findings. Here are two examples of positive findings

    www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8012056&dopt=Abstract

    Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50, and 200 Hz.

    Salford LG, Brun A, Sturesson K, Eberhardt JL, Persson BR.

    Department of Neurosurgery, Lund University, Sweden.

    The results show albumin leakage in 5 of 62 of the controls and in 56 of 184 of the animals exposed to 915 MHz microwaves

    And,
    Electromagnetic fields (1.8 GHz) increase the permeability to sucrose of the blood-brain barrier in vitro.

    Schirmacher A, Winters S, Fischer S, Goeke J, Galla HJ, Kullnick U, Ringelstein EB, Stogbauer F.

    Klinik und Poliklinik fur Neurologie, Universitat Munster, Germany.

    Exposure to EMF increased permeability for (14)C-sucrose significantly compared to unexposed samples.

  87. j said,

    May 24, 2006 at 4:53 pm

    Hector, you say that “Either they leak or they don’t. Its not scaremongering to say they do when someone says they don’t. Neither does this constitute a health claim or scare.” Does anyone claim that microwaves don’t leak *at all* nowadays (has anyone who knows what they’re talking about ever claimed this)? You seem to have got the idea that people are trying to hide this fact – why?

    You also say that “get ready to explain to people not to have accidents like putting in the wrong number into the timer or forgetting to put in the food/water, and that actually such slips expose them to a level of microwaves not necessarily safe. Trouble is, that would obviously tell them about the leaking and they might not buy the product.” A lot of UK homes have gas boilers and/or cookers. These can be much more dangerous than microwave ovens if malfunctioning or used improperly – can lead poisonous and/or flammable gas, and they do clearly lead to a number serious injuries and deaths. However, people are quite prepared to live with certain risks if it brings them corresponding benefits.

  88. Aspiring Pedant said,

    May 24, 2006 at 5:01 pm

    Hector, Jasont.

    According to a Doctor who specialises in ES –

    •There are no diagnostic testing facilities for ES in the U.K. diagnosis rests entirely on the patient’s observation and symptoms.

    •Due to the lack of diagnostic tests, ES is a useful diagnosis for a malingerer to adopt. Only experience with the condition can distinguish the difference.

    •At present, there is not a cure as such. Treatment depends on detection, avoidance and protection. However, if exposure is reduced by avoidance and protection measures, the sensitivity appears to lessen.

    •ES is not fatal, except insofar as it impairs judgement.

    With that in mind how can people be sure that emf is the cause of any health problems?

  89. Hector Ballast said,

    May 24, 2006 at 5:17 pm

    j

    “You seem to have got the idea that people are trying to hide this fact – why?”

    No – I pointed out they leak and its resulted in a mixture of reactions inc. flak, like I was scaremongering. Others questioned my credentials for switching on a machine and reporting a buzz (sad of them I know). Cant defend opposite positions simultaneously when I didn’t hold either.

    “I was trying to state that any experiments that aim to quantify the RF leakage from microwave ovens in order to ascertain whether it is of a sufficient level to be a possible risk to human health should be undertaken under more normal use situations and not under environments which violate the manufactures instructions and which could theoretically result in artificially high results”

    ie – there may be a safe limit as long as the MW isn’t empty, but there could be accidents that resulted in it becoming empty. People know if they leave the gas running its dangerous but they don’t know there could be dangers in the MW. That’s all I was saying.

  90. Andy said,

    May 24, 2006 at 5:22 pm

    Jasont,

    While I’d be impressed if it was possible for something as small as a human brain to be even slightly effective at picking up EM radiation at Here is the abstract of the article you mention. A little digging indicates that Dr Neil Cherry spent a lot of time on EMF and has a far better scientific background than a lot of the Dr’s who get mentioned in this place. Hopefully someone who has a better understanding of the subject can take a look at that paper.

    I did like the products on the blockEMF site. Some of them are based on valid effects (e.g. RF shielding) but strike me as over sold and very over priced. I have half of that stuff sitting around in the lab at work and didn’t pay anywhere close to those prices. Others items are a fine mixture of psudo-science and snake oil.

    Nice to see that they have the standard FDA disclaimer “Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.” and the get out of jail free disclaimer that “We are not responsible for incorrect or outdated product descriptions”

  91. Hector Ballast said,

    May 24, 2006 at 5:25 pm

    Andy

    Quotes were incorrect, meaning the same, apols.

    “Personally those numbers strike me as very low. You may disagree but you should check what you are disagreeing with first.”

    Actually you should make this point to the poster to whom I was pointing out that possible health effects should not be dismissed without consideration of the levels. Do I need to keep repeating I didnt claim to have establushed risk?

    But now you have got the levels – what are they? Eg , how would they compare with eg a cordless phone, a mobile? Just wondering

  92. Andy said,

    May 24, 2006 at 5:35 pm

    Correction to post 98:
    The use of the less than symbol seems to have broken the html link and cut out some text. I’ll have to remember that for the future.

    The the first paragraph should have read:

    While I’d be impressed if it was possible for something as small as a human brain to be even slightly effective at picking up EM radiation at less than 5Hz I don’t have any knowledge or papers to point to that would disprove this.
    Here is the abstract of the article you mention. A little digging indicates that Dr Neil Cherry spent a lot of time on EMF and has a far better scientific background than a lot of the Dr’s who get mentioned in this place. Hopefully someone who has a better understanding of the subject can take a look at that paper.

  93. Andy said,

    May 24, 2006 at 5:42 pm

    Hector,

    I am very tempted to simply tell you that other people have already given the required information and I don’t know why you keep asking for things when you are ignoring the evidence that has already been given.

    But I won’t.

    The maximum leakage levels for new and old ovens and the level for mobile phones are both given in the radiation section of the wikipedia page on microwave ovens.

    Now please excuse me while I go and quickly change the numbers on that page before you look at the link…

  94. Michael Harman said,

    May 24, 2006 at 6:25 pm

    Re microwave ovens and what happens if there is nothing in the oven, this is explained by Robert Carnegie in Post 76. The field level in the oven may increase a bit, but the power flows back, so to speak, into the emitter (the magnetron) and is absorbed by that. That doesn’t do the magnetron any good at all, but it has no other major effects.

    The leakage from a microwave oven is something like a thousandth of the field level inside it. So if there’s nothing in it, the leakage power will increase slightly, but not by very much.

    The Wikipedia link from Andy (post 102) explains what the legal leakage limit is. That limit is for the worst case, ie an empty oven, and practically in contact with it.

    And just for those too lazy to look it up, the leakage limit at 5 cm (2 inches) from the oven is about the same as the radiation from a mobile phone. Since people don’t normally go about with microwave ovens held to their ears (or other parts), the inverse square law means that in practice, the radiation exposure will be far less than that, ie a long way below the safe limit.

  95. Michael Harman said,

    May 24, 2006 at 6:37 pm

    PS. Andy: your “Abstract” link in post 101 only leads to a home page, which looks as if it needs logging in to.

  96. Hector Ballast said,

    May 24, 2006 at 9:16 pm

    Thanks – I was hoping to be spoon-fed the cordless levels too

    New MW 1 mW/cm2
    Old MW 5 mW/cm2

    Mobile 3.2 mW/cm2 . Interersting anyway.

    Andy, I should clear something up from eariler when I said Powerwatch measured paint screening efficiency with the meter. They would have been referring to the nickel-based paint they sold up unitl very recently. The carbon-based paint is new. The nickel claim was 98% so we were talking about diferent things – my fault, sorry. Free tin on the way…Your attribution of the claim of 99.9% for carbon-based paint is correct, and one-coat too. The carbon-based paint seems a better deal than the nickel, damn.

  97. Andy said,

    May 24, 2006 at 10:33 pm

    Maybe it goes on it a thicker layer or the 70% non-Ni part of the old paint caused too many problems.
    Either way 30dB isolation from 0.9 to 18GHz still seems far better shielding than I would expect anything like that to obtain.

    10dB I could believe. 20dB would be impressive. 30dB is just too good to be true. If paint like layers were that good at shielding we wouldn’t be going to the expense of Ni coated magnesium to shield sensitive electronics from outside noise.

  98. Fyse said,

    May 24, 2006 at 11:10 pm

    Hector –

    “Others questioned my credentials for switching on a machine and reporting a buzz”

    Are you talking about me? I was genuinely interested to know what you did. I misinterpreted your comment about being ‘lead scientist’ at face value, and was therefore curious to know what your job was. It was genuine curiosity, and I only asked about the microwave thing specifically because that was the trigger for my inquiry. Honestly.

  99. Fyse said,

    May 24, 2006 at 11:50 pm

    Andy –

    I’m no expert, but I had a look at that abstract and I’m concerned at the lack of figures to support the claims. Basically, he examines the correlation between changes in sun activity and human health to gain evidence that the Schumann Resonances have an impact on the human body (since they could plausibly be effected by changes in solar activity). There are lots of statements like ‘extremely highly correlated’ and ‘provides strong support’, but no details of the statistical tests performed. Good scientific practice dictates putting such evidence directly in the abstract, so it doesn’t fill me with confidence. He also mentions lots of past studies but unfortunately you have to pay to see the references. The whole thing seems mighty dubious to me.

    There was also the following quote on the guy’s website…

    “It is also scientifically sensible and proven that placing a cellular telephone next to your head … causes serious alterations of brain activity, leading to elevated rates of a road accidents, headaches, nausea, dizziness, loss of concentration and memory, DNA damage and enhanced cell death rates, and significant increases in brain cancer rates.”

    Really? It’s the radiation from the phone that causes people to crash their cars? So, not that they’re distracted by talking and pressing buttons then?

    (Also, I never heard about actual proof of a link between cellphones and brain cancer. Did I just miss it, or is that simply not true?)

  100. David S said,

    May 25, 2006 at 5:01 pm

    Hector –

    Yes microwave ovens leak. All electrical devices leak some for of electronic noise. You say your ‘acousticom monitor’ went crazy during your experiment. Ok, that’s great. What is an ‘acousticom monitor’? I work in the EMC field, dealing with emissions and immunity to radiated electric fields every day, and have never heard of it.

    This might be a better idea for you. Take a look at your microwave oven. Somewhere on the back, usually by the plug there will be a bunch of lables that most people ignore. FCC, CE, UL, and other markings should be back there. You can contact either UL or the manufacturer to receive information on the testing that was done on this device. All devices that are currently sold in the USA and EU must undergo emissions testing, and the emitted level must be fairly low to pass.

    If you cannot find the information or want to conduct your own experiment, find a certified EMC testing facility. They will run your microwave oven through the standard testing procedures, and will be able to tell you what levels and frequencies are being emitted by it.

  101. Hector Ballast said,

    May 25, 2006 at 11:10 pm

    Useful answer but the MW is in the bin….the issue of the leaking cropped uo indirectly in a discussion about screening materials – I was only having this discussion because others seemed endlessly fascinated by it. It even seems more interesting than all the evidence about phone masts Ben is ignoring.

  102. coracle said,

    May 26, 2006 at 8:46 am

    Well Hector, do you have some proper references for Ben to look at?

    The TNO study is of no use by its own admission, I’ve been unable to find Wolf or Oberfeld and I’m not inclined to look for the others if they haven’t been published.

    Come on, you know what we need: journal, date, volume number, page number, author, title

  103. chillycold said,

    May 26, 2006 at 1:57 pm

    As one of the members of the evil tribe whose function it is to try an obtain planning permission for mobile phone masts. With the most enjoyable role of sitting in planning committee listening to the well researched and unbiased soundly based objections from resident and councillors to mobile phone mast which mean we only get sites by wasting tax payers money and forcing that government agency that is the planning inspectorate to give us permission despite the fair and democratic process that resulted in a refusal

    I have often wondered when I am accused of risking the next ten generations of young Briton with cancer brain tumours etc why when the scientific evidence is so clear what harm am doing why do these thoughtful and obviously concerned parents continue to buy their delightful progeny mobile phones and upgrades. I can only assume it is down to the subliminal sales technique used by that possibly more hated sector known as advertising that is whipping the children up to such a state that the parent are willing to allow their little darlings to risk death by using mobile phone.

  104. Hector Ballast said,

    May 26, 2006 at 2:35 pm

    Hi chillycold

    You dont offer any info – Is your post just a moan? Nothing wrong with that. What do you say to this:-

    [Parents should read: 20 expert warnings on mobiles/child safety www.emfacts.com/papers/children_mobiles.pdf

    Anyway, as I understand it, mobile operators don’t usually listen to anything about health, well-researched or not. Any question, statement, document or pile of folders related to public health concerns is answered by the same misleading reference to thermal safety limits that are irrelevant to these concerns. No wonder its dull.

    Re: putting children at risk etc

    To alleviate the accusations you describe, why not stay awake long enough to take some of the well researched and unbiased soundly based objections you have heard in the planning committees, including evidence of health effects from mobiles, and start giving it out to parents and children, instead of Disney adverts and free ring tones and other devices to market the technology to children.. Stop putting masts near schools and on top of hospitals and baby wards. You might start to feel much better !

    Hector

  105. monty28 said,

    May 26, 2006 at 4:14 pm

    just sitting back and admiring my £1318.23 beautiful new paint/curtain combo….

  106. monty28 said,

    May 26, 2006 at 4:15 pm

    oww just got a shock…

    it’s a con – leave it alone!

  107. Michael Harman said,

    May 26, 2006 at 7:14 pm

    Hector Ballast (post 112) refers to an Australian study, emfacts, which summarizes “20 expert warnings”. Looking at item 10:

    … a small unpublished Spanish study, examining changes in brain activity after a child uses a mobile phone. … The subjects were an 11-year-old boy and a 13-year-old girl. Using a CATEEN scanner, linked to a machine measuring brain wave activity, researchers were able to make photographic images of the changes in brain electrical activity. … “We were able to see in minute detail what was going on in the brain. …”

    I don’t know what a CATEEN scanner is, though I assume it’s some sort of CAT scanner. What sort of fields does that expose the subjects to? I guess a great deal stronger than the fields from a mobile phone. And what sort of safety evaluation has been done on CATEEN scanners, particularly when used on children? How does that evaluation compare with the sort of concerns which have been raised, on grounds of varying degrees of plausibility, to mobile phones?

    I think there’s a case for being more concerned about the two subjects of that study than about mobile phone users generally, or even children in particular.

  108. Hector Ballast said,

    May 27, 2006 at 11:20 pm

    The ESC could certainly bring on a psychosomatic illness in me. But thankfully, it doesn’t pick up radio waves. Its a microwave monitor – useful to tell you for example where mast signals are lowest in your house. Or how to dodge signals from their neighbours cordless (if you’re that way inclined). You can also tell GSM, 3G and Tetra mast signals apart which is useful for some people.

  109. Ben Goldacre said,

    May 28, 2006 at 1:28 am

    just got this excellent email from Rod Read, the head of Electrosensitivity, more than happy to print it as he requests:

    “Re: Disgusting Ben Goldacre

    Oh dear, this is turning nasty,

    several times it has been suggested by your Joseph Harker I should write a letter, so lets have you print it.

    Rattled old Ben Goldacre down in the gutter again, such a high-falutin scientist when he can make the facts fit, and down in the gutter when it pleases him if they won’t.

    And paid to have his high and mighty pedestal, to swing left and right, by you.

    So he offends hundreds with insults and innuendo, then, when his nose is pushed in the evidence and he wobbles, acknowledging risks “the mobile phone network being a danger to health – which could well turn out to be the case”, but hey retrieve it, with a mass smear none of us can know to be true. Like a squid retreating in a cloud of stinky gas to cover his passage.

    We do know he had many genuine accounts of electro-sensitive illness sent in. What about Brian Stein then Ben? Explain away his lucid detailed account of how he runs a 500 million pound a year company, with an electricity-free office, because of what heavy mobile use did, and does, to his health. Oh no. Pick one wishing you get cancer, an emotional response to insult, far more ‘scientific’. Now I am into sarcasm, that is what it does to you, dealing with those down in the intellectual gutter.

    Off he goes disdainfully holding his nose in the air, he disgusts many of us with his chicanery deceit and double standards. No wonder some blow their tops..and you pay him, ugh.

    Yours sincerely

    Rod Read”

  110. JQH said,

    May 28, 2006 at 3:55 pm

    Glad to see Rod Read is using calm, rational analysis of the data as opposed to Ben’s insults and innuendo…..

  111. Delster said,

    May 29, 2006 at 2:38 pm

    As far as microwaves leaking radiation goes.

    What you have is a device that is designed to produce a form of moderatly penetrating EM emmission which induces a thermal effect in objects placed within the effective area (ie inside the thing)

    To totally shield the devise to prevent all leakage would entail much thicker shielding all round and probably some kind of double door affair as well and probable reinforcing your worktop to take the weight.

    We had a microwave oven back in about 1980-2 i think it was and we were warned, when purchasing it, that there was a small amout of leakage and simply to not be in very close proximity while it was working…. so if you don’t go pressing your eyeballs to the glass you should be just fine!

    The emmission that escapes the shielding is very low and when combined with the inverse square rule means you would probably have to be continually leaning on the glass while it was running for extended periods on multiple occasions to do more than discomfort the occasional skin cell… which are dead anyway!

  112. AJH said,

    June 2, 2006 at 12:22 pm

    If you use, as I did last year, an AV sender to watch Sky in the kitchen, it goes screwy when the microwave is on. Clear evidence of leakage in the 2.4GHz spectrum I’d have thought.

  113. Delster said,

    June 2, 2006 at 1:28 pm

    AJH,

    microwave ovens have a transformer in them i believe…. so it could be the pesky magnetic fields from that……

  114. topazg said,

    July 24, 2006 at 12:35 pm

    Sorry about the long delay in finding this thread :

    @ JQH (post 13): We will soon be posting full details of how we performed screening measurement on the Powerwatch website.

    @ Frank (post 16): We know Grahame Blackwell personally, and I think it is fairly likely that he will answer any questions you have directly, instead of just criticising his lack of open evidence on here which he probably will not see. He may not, but it is certainly worth a try.

    @ Hector (post 28): The piece of equipment used for measuring wasn’t an Acousti-com, but a spectrum analyser from Anritsu (MS2721A – retails at about 10,000 pounds) which gives exceptional data recording and logging facilities. Again, this wil be part of the write up of the screening measurements.

    @ Hector (post 47): As mentioned above, it wasn’t a hand-held meter we used, but a considerably more sophisticated piece of measuring equipment.

    @ Robert (post 120): The acousti-com is not a standard retail AM radio receiver, (though I guess it is retail of some description as EMFields sell it), but works by converting incoming pulsed signals across a set Microwave frequency band into an analogue audio output. It was designed by Powerwatch.

    We will happily answer any technical or scientific questions regarding any of this subject or related ones for those still watching the thread.

    Best Regards,
    – Graham
    Powerwatch

  115. ttrtilley said,

    October 31, 2006 at 7:10 pm

    I want my cellphone (and my students phones) to not ring during class. High school science taught me that putting the phones in a metal box would prevent them from ringing However, Andy is right. Never trust a Faraday Cage. I tried cleaning the paint off the overlapping lid seal. Still rang. I put in a bottle of water. Still rang. Put the box, phone and all, inside the microwave oven. Silence. Similarly for box with phone inside stainless steel roastpan. Nesting cheap Faraday cages is easier for me than trying something exotic and expensive. All I need is a bigger biscuit box. Or paint my classroom with that conducting paint :)

  116. topazg said,

    November 7, 2006 at 3:57 pm

    It is almost impossible to stop a phone from ringing, as they are capable of working (receiving signal at least) at astonishingly low levels. Certainly the material we provide will not stop a phone from receiving a call inside, though making a phone call inside would rather defeat the object of the screening – However, it does make an enormous reduction to the field strengths that a number of sensitive people find very helpful.

    Best Regards,
    – Graham

  117. ttrtilley said,

    December 2, 2006 at 6:21 pm

    Success! I have found a metal box with 2 lids. If both the inner and outer lids are properly closed, then the phone does not ring. Written on the box is: “Starbucks Eggrolls”, “Printed in Hong Kong”, and a bunch of Chinese characters.

  118. Reduce Debt WebLog » Blog Archive » InterDok - MInd: The Meetings Index said,

    August 1, 2007 at 4:04 am

    [...] Bad Science » I have nothing to declare but my cheekiness Let’s say you were worried your health was being harmed … Exposure to GSM-900 or GSM-1800 electromagnetic fields had no … signal here and there!?) would be enough for the communication to be … www.badscience.net/?p=241 [...]

  119. Ben Goldacre: Bad Science « Asylum said,

    September 25, 2008 at 8:00 am

    [...] He’s as keen to denounce hysterical anti-GM crop protests as he is to criticise Monsanto. He points out that anyone worried about the health effects of radiation from mobile phones should live as close [...]

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  121. lukeright said,

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