Firstly, MRI scanners use different frequencies to devices like mobile phones or handheld computers that electrosensitive people like myself have complained about. Electrosensitivity may well be frequency related in which case there might not be any effect from an MRI scanner in spite of the intensity of the fields it produces.

Secondly, how many people have regular MRI’s? Sure, you might have a once off MRI for something. But suppose you are electrosensitive to the MRI machine, how would you be sure unless you’re having regular scans to know of a correlation?

An average 1.5T scanner operates at a peak RF power of 16-20KW (at around 63MHz) – though obviously the duty cycle is low, or thermal effects would cook the patient.

Even so, an average power deposition in the body approaching 0.4W/Kg is usual.

If we believe some of the worst rantings of the electro-sensitive lobby, we should be able to detect a substantial group of patients whose health has deteriorated after an MR exam, due to EM effects.

I don’t recall seeing any such correlation reported…must be Big Pharma’s cousin, Big Scanner Manfacturer suppressing the data.

I absolutely agree. There are a whole load of other ‘real’ causes that need to be discounted. Given that the effect is not immediate, it may not even be the device. It is so easy to see faces in the wallpaper and impose structure on random coincidence.

Paul,

Are you effected by wifi? Are you effected by power lines? I find the whole pda thing troubling because I don’t see that that would be generating much of an alternating field. Could somebody confirm this?

I can see that perhaps your pda could cause a localized effect, but spots in front of your eyes? What mechanism could be causing this? Are you sure they aren’t just common or garden floaters?

Tom

My DECT phone base interferes with my hi-fi, including wireless headphones; the intermittent buzzing noise is very upsetting – so I don’t use the headphones too close to it. And, come to think, when I recharge batteries, I notice a “chemical” smell – I wonder if I bought too cheap a brand, or if I’m charging them too hot.

And I hate flickering fluorescent lights.

But on the whole, technology doesn’t make me ill – with the other very major exception of keyboard use, which has driven me to use touchscreen stylus input instead for several years, specifically the excellent Fitaly program. To other users, if the keyboard causes any discomfort at all, I strongly recommend a more ergonomic design, with the wrists aimed in from the sides of the body, instead of straight ahead to the keyboard and therefore bent. So, the keyboard layout can be either curved, or split in the middle and twisted around. Too late for me, though!

I understand what you’re saying, but I’m sure the symptoms are not “physiological noise” or anything like that because I can’t simply tune out from them as though they were there all the time and I was just being introspective. They are very uncomfortable to say the least.

Why no study to date has shown electrosensitivity to be correlated with EMF exposure, I don’t know. But perhaps the way the experiments are conducted needs to be reconsidered and perhaps a larger sample size used. I don’t know. But I am confident that one day there will be a study able to be repeated that will show electrosensitivity symptoms are not simply “all in the mind” and that EMF’s from the devices are the most likely explanation.

-Paul

one other thing, if you’re going to do some self experimentation you need to be very clear on what you’re testing. If you have too long a list of symptoms whose presence will qualify as a result you’re bound to get some significant hits by chance alone. Pick a symptom you’re sure of and that’s to easy define and easy to test and stick to that. Then you need to do some blinded and unblinded tests to see if there is a difference. Remember, even if there is a difference, it might not be due to EMF but some other property of the device.

Tom

The other thing is that your symptoms seem to be the kind of physiological noise that one might become more aware of if one was looking for them. I am ordinarily unaware of the pressure in my sinus but in typing this I am becoming aware of a slight pressure.

Tom

in the cold dank world beyond the reach of the warm sun that is Ben Goldacre, this issue has been investigated to death. I’ve been reading up on it for the past couple of weeks.

The reason for the 50-60Hz thing is that if it’s a static field then it would be drowned out by the Earths magnetic field, the theory goes that an alternating field is new and artificial and therefore we aren’t adapted to it.

Tom

you mention various frequencies in the MHz range. Generally speaking the anti-EMF movement has been concerned with frequencies around 50-60Hz because of the link to AC power transmission. The argument generally is that there are ‘pulses’ within the higher frequency waves in the 10-100Hz range that cause the trouble. In so far as I’m aware of it though the vast bulk of 30+ years of research indicates that there is no effect even within this range. One question though, what kind of EMF field will be given off by a pda running off the battery? All the talk about fields given off by hairdryers etc have been with them plugged into the AC mains.

Tom

you cover a lot of ground. One thing to point out is that over the years CB radios have been credited muddled up in this as well (cancer risk for one thing, I’m not sure about EMF sensitivity).

Do you get symptoms from power lines? Again, these have traditionally been seen as causing both the cancer and the sensitivity.

Can somebody suggest a good readable paper on this whole confirmation bias/misattribution of cause thing that we all feel is going on here? Preferably with a killer anecdote or two. An anecdote is afterall worth a thousand statistics.

Tom

but surely if there are people who genuinely manifest acute symptoms in this way, then they should be easy to test. In 30 years nobody from any of the anti-EMF groups has presented such a case? Or have they?

Tom

I got a chance to read the full Essex report and you’re right. Yes it is interesting. There are degrees of electrosensitivity. Those ES participants who had to drop out of the study are so badly affected that “exposure” leaves them ill for days.
Others can detect the “exposure” but their ES is not anywhere as debilitating. It’s perfectly possible to be electrosensitive without it affecting every move in your life. Threshold might be the keyword here.
You can check out one badly affected participants testimony here:
http://www.next-up.org/pdf/TestimonyBrianSteinAnEssexVictim28072007.pdf