Is EMF sensitivity a real thing?

Wolfcub

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It is bound to have some effect, I feel. But like many things, there will be some who are more susceptible to negative effects, and some for whom it won't make any difference really.

As we have electro-magnetic parts of our bodies/brains, I do feel that there has to be some influence however. But many will probably withstand it quite happily..... How it will affect the sensitive or chronically unwell people, I can't say. I don't think anyone knows yet.
 

Pyrrhus

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A discussion from another thread:

In a broader sense, there are plenty of epidemiological studies over the years that have failed to find any strong correlation between electromagnetic fields and human disease. These studies have largely formed the basis for the prevailing opinion that electromagnetic fields are perfectly harmless.

However, consider:
  • Researchers performing in vitro work have used electromagnetic fields to induce oxidative stress in living tissues, to study ion channels in cells, or merely to heat up tissues.
  • People with no history of electromagnetic hypersensitivity have reported neurological disturbances after undergoing an MRI using the experimental 7T machines, which use electromagnetic fields that are much more powerful than current MRI machines.
  • A friend of mine, who has never complained of electromagnetic hypersensitivity, went into a 3T MRI machine for a routine MRI, and had uncontrollable leg movements every time they switched on the machine.
  • Some animal studies found a slight increase in tumors in some animals exposed to electromagnetic fields.
That is completely beyond the levels of EMF that people claim to be sensitive to. A gigawatt laser is "EMF", and causes harm to human flesh, but that doesn't mean that typical moonlight is going to crisp your flesh. I'm not sure how many orders of magnitude the 7T fields are higher than the fields from house wiring, but it's a huge difference. Magnitude does make a difference. Some physical effects will simply not occur below a certain threshold of power level.
Yes, when talking about the impact of electromagnetic radiation on human tissue, you must always specify which frequency and which power output you are talking about. These two variables will determine whether there is an effect, and if so, how large the effect will be.

For example, microwave ovens generate electromagnetic radiation that quickly burns flesh at the frequency of 2.450 GHz and a power output of 800W.

But a typical WiFi router can also generate electromagnetic radiation at the same frequency of 2.450 GHz, but with a power output of only 1W.
Actually, the legal limit seems to be 1/10ths of that: 100 mW. I'm not sure whether that's measured right at the antenna, or if it's the amplifier output, with the actual transmitted power being lower. The power level from a wifi unit in a house will be much lower at a distance, so while sitting at your computer, you would probably be exposed to several orders of magnitude less. I can't find a simple answer to 'what is the typical power level experienced in a house'. From my setup, I'm guessing that I'm exposed to somewhere around 10 nanowatts of wifi power. No, I'm not concerned about 10 nW, and I really don't believe that any human can reliably sense that level of EMF.
 
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EMF sensitivity is only "real" in the sense that it causes genuine suffering for those who are convinced they are suffering from it.

The topic isn't studied much because it's understood that the issue is not a physical matter. It's easy to demonstrate that someone's supposed EMF sensitivity matches to visual cues (seeing a WiFi router, seeing a cellular phone) but does not correlate to actual measured RF power.

Many people don't understand how electromagnetic radiation decays with distance. A WiFi router may emit 1 Watt of peak power during transmissions, but that power doesn't go directly into the body of someone nearby. If it did, there wouldn't be any power left for anyone to receive a signal on their phone, so this much is easy to prove. The amount of power reaching any one person minus the amount of power reflected away from their body would be measured in picowatts or less. A picowatt is 0.000000000001 Watts, which isn't enough power to do much of anything.

A common mistake is to confuse studies at different frequencies or power levels, or to confuse electromagnetic radiation with magnetic fields. For example, @Pyrrhus posted a study above showing that extremely powerful pulses at 50Hz and 1mT could cause observable effects in slices of animal brains. Such a study might be useful in the context of Transcranial Magnetic Stimulation (TMS), but it's not relevant to something like using your cellular phone due to the different frequencies (differing by a factor of 100,000,000) and different types of field (electromagnetic waves compared to magnetic pulses).

To put it in perspective: The field strength used in that study was 1 mT. A typical refrigerator magnet, which can hold papers to a steel surface, is around 5mT. Your cellular phone and WiFi router certainly aren't coming anywhere near that strength in the B-field.

I could write all day about this (it overlaps with my academic background) but the unfortunate reality is that it probably doesn't matter much. Those who are convinced that they react to RF radiation sickness are not actually suffering from direct effects of electromagnetic radiation in the air. The types of reactions experienced by sufferers don't actually correlate to measured RF levels, but rather to the perception of the presence of RF generating devices.
 
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Another comment from a different thread:
The high-power, low-frequency electromagnetic fields discussed in those studies are not comparable to the low-power, high-frequency signals emitted by cellular phones.

A more appropriate comparison would be rTMS (transcranial magnetic stimulation) which uses powerful, localized electrical fields to elicit biological reactions in tissues. It's a common mistake to equate these high-powered magnetic fields with cellular phones and such, but they actually have very little in common.

The energy that comes out of a cellular phone is actually much closer to to visible light (which is also electromagnetic radiation) than to these extremely low frequency magnetic fields. It's a mistake to mix the two topics.
 
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The topic isn't studied much because it's understood that the issue is not a physical matter. It's easy to demonstrate that someone's supposed EMF sensitivity matches to visual cues (seeing a WiFi router, seeing a cellular phone) but does not correlate to actual measured RF power.
that was never the case in my case.

The body when sufficiently weakened, can be more readily penetrated and you feel it penetrate.
 

Wishful

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The body when sufficiently weakened, can be more readily penetrated and you feel it penetrate.
Can you provide data about how EMF penetration depends on the health of a body? I very much doubt it. It would be reasonably simple to test experimentally: measure the EMF passing through a body while administering something to induce 'illness' of some sort. I expect it would show no significant difference.
 

hapl808

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I would say just because we can't measure something doesn't mean it isn't happening. Otherwise none of us would be here. But the corollary is also not true - just because we can't measure something effectively doesn't mean it IS happening. Therein lies the problem.
 
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Can you provide data about how EMF penetration depends on the health of a body? I very much doubt it. It would be reasonably simple to test experimentally: measure the EMF passing through a body while administering something to induce 'illness' of some sort. I expect it would show no significant difference.
this is my own personal experience, and there is no data. Perhaps this EMF I can hear and feel has no negative effects on the body whatsoever.
 
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I would say just because we can't measure something doesn't mean it isn't happening. Otherwise none of us would be here. But the corollary is also not true - just because we can't measure something effectively doesn't mean it IS happening. Therein lies the problem.
In this case, we actually can measure both the electromagnetic radiation and the reported symptoms. There have been numerous studies on the topic but the outcome is always the same: Study participants claiming EHS report a lot of negative symptoms, but the symptoms are uncorrelated with the electromagnetic radiation. Researchers can place sham electromagnetic sources in the room with the patient (a fake WiFi router, for example) and the patients will begin to report worsening symptoms.

People who claim to suffer from EHS are indeed suffering real symptoms, but they are mistaken about the cause of those symptoms. Electromagnetic radiation cannot be "felt" or sensed at the levels present in household environments and numerous studies have confirmed this even in claimed EHS patients. Whatever the EHS patients are feeling is not coming from electromagnetic radiation.
 

Pyrrhus

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