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Inasmuch as the hypothesis is that the E/M fields from the power lines themselves cause various ailments... well, go out near a power line with a compass. If you get no noticeable effect on your compass, it is safe to say that the E/M field from the line is well below background (and no, the sort of E/M field you get from a DC or 50 Hz line is not substantially different from the Earth's magnetic field).

If the hypothesis is that electrical discharges ionise pollutants already present in the air, then you have something that at least isn't prima facie nonsense. (But where are those discharges coming from? Failure of the isolation? That would be a far more serious problem than any amount of particulate matter ionised in the process.)

The problem with citing individual studies is that there have been well over a hundred studies on HV lines over the years - so purely on the basis of a 5 % significance threshold, it should be possible to find a handful of independent studies confirming an effect. What we'd really need is a meta-study. Unfortunately, the places I usually go for a summary of the epidemiological literature turned up dry (Orac has nothing and Quackwatch debunks the EMF nonsense but does not consider aerosol generation from sparks).

- Jake

Friends come and go. Enemies accumulate.

by JakeS (JangoSierra 'at' gmail 'dot' com) on Thu Apr 14th, 2011 at 10:37:05 PM EST
[ Parent ]
from the Earth's magnetic field, which, among other things, does not oscillate at 50 to 60 times per second.  

The major, major scientific fallacy here is to extrapolate from a theory that is inherently unable to model a situation (electromagnetic theory has no way to imagine biological effects of EM radiation) to conclude that no effects can exist, and then to use that theoretical conclusion to discredit anecdotal reports of real observation--on the basis of their being anecdotal despite that being the only kind of report you can ever have at the outset of a new scientific investigation.  

If I were being uncharitable, I would not call such science merely bad, but corrupt.  

On the phenomenon itself, I do not weigh in.  Maybe will see--if anyone ever studies it.  

The Fates are kind.

by Gaianne on Thu Apr 14th, 2011 at 11:42:48 PM EST
[ Parent ]
50 Hz is ultra-long-wave radio. You don't get resonance with any molecular bonds for another nine orders of magnitude or thereabouts. You don't get ionisation for another fourteen or fifteen orders of magnitude. It's not quite as implausible on the basis of elementary physics as homeopathy, but it's certainly in the same ballpark.

And it has been studied. Extensively. And while I'm not current on the literature, the fact that proponents of the hypothesis cite only individual studies as opposed to meta-studies (and the fact that it is prima facie implausible as a matter of basic physics) is not encouraging.

- Jake

Friends come and go. Enemies accumulate.

by JakeS (JangoSierra 'at' gmail 'dot' com) on Fri Apr 15th, 2011 at 01:24:16 PM EST
[ Parent ]
Only a strong supposition based on epidemiological and anecdotal elements.

When I see stuff like : there's no evidence of harmful effects to animals, as long as you keep feeding troughs and all other metallic elements grounded... yeah well... I would prefer to see evidence of thriving animal breeding installations under power lines, because all I know about is counter-examples.

Unfortunately, the places I usually go for a summary of the epidemiological literature turned up dry

That's interesting. So little study of something that is so important economically to such powerful actors as (generally) national-monopoly lines companies... Move along, there's nothing to see here...

It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II

by eurogreen on Fri Apr 15th, 2011 at 04:21:27 AM EST
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They came up dry on the particulate matter hypothesis, not on epidemiological studies of power lines, which, according to Quackwatch, show no effect.

I would prefer to see evidence of thriving animal breeding installations under power lines, because all I know about is counter-examples.

Anecdotes are all well and fine if you have some sort of plausible hypothesis worth testing. But if your hypothesis is that the electrical field from a power line has biological effects... well, let's take a 1 GW, 10 kV power line. That gives you a current of 100 A, which translates to a magnetic field of 10 microTesla at three meter, or 1 microTesla at 30 meter. That's between a half and one and a half orders of magnitude less than the Earth's magnetic field, and between one and two orders of magnitude below the German continuous exposure limit (yes, the Germans have a limit for magnetic field exposure). And, as noted upthread, 50 Hz doesn't resonate with any molecular or inter-molecular bonds.

Oh, and 1 GW lines are DC lines, which means the fields don't oscillate at 50 Hz. AC lines are at least an order of magnitude smaller.

So if I had a million € for an epidemiological study, an application to study the health effects of E/M fields from high-voltage lines would pass the payline unless it was a really thin field.

- Jake

Friends come and go. Enemies accumulate.

by JakeS (JangoSierra 'at' gmail 'dot' com) on Fri Apr 15th, 2011 at 01:47:55 PM EST
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