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Author Topic: Is there any risk living under power lines?  (Read 53547 times)

Offline Geezer

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Is there any risk living under power lines?
« Reply #50 on: 17/10/2010 18:57:37 »
Lee,

I am not claiming an undisputed fact. My position is simply "there is no known scientific evidence that connects cancer with power lines". That does not say there never will be, it's just the current state of understanding.

You have said EMR (btw - more correctly we are discussing the effects of ELF) "can" cause cancer. If that's true, I'd like to see the evidence and an explanation for the mechanism.

According to Edward W. Campion, M.D. (New England Journal of Medicine, 337:44, July 3, 1997):
 
"there is no convincing evidence that high-voltage power lines are a health hazard or a cause of cancer...18 years of research have produced considerable paranoia, but little insight and no prevention. It is time to stop wasting our research resources. We should redirect them to research that will be able to discover the true biologic causes of the leukemic clones that threaten the lives of children."
 

Offline techmind

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Is there any risk living under power lines?
« Reply #51 on: 10/12/2010 00:28:50 »
It's history now, but Karen didn't say what voltage/power the lines were.

In the UK we have 11000V, and 33000V on overgrown telegraph poles, then 100000, 275000 and 400000V on big metal pylons.

I wouldn't think twice about the 33kV stuff.


The 100kV and upwards does make a nice substantial electic field at the ground, somewhere of the order 900V/m ... (I think the NIRP safety limit is about 10000V/m) but that will almost certainly be screened by any building and won't penetrate to the living area. It's all high-impedance and won't penetrate your body anyway. With UK 100kV lines (rated at about 300A per conductor - typically 2 sets of 3 phases on a set of pylons) you can get substantial magnetic fields (still within NIRP guidelines, but not with much headroom IIRC) - which won't tend to be screened by the building. Right under the pylon, the magnetic field would be strong enough to make a the picture on CRT monitor shimmer, and would be likely to cause hum in audio and TV installations.

The magnetic field would still be weaker than you might experience right next to a domestic vacuum cleaner or lab power supply (or the corridor/office next to the switchgear at your workplace) - but you'd experience it everywhere in the house, almost 24/7.

With the UK configuration of cables, the magnetic field decreases rapidly with distance, and (eg for 100kV/300A cables) much reduced even just 30 metres away from the centreline.
 

Offline Geezer

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« Reply #52 on: 10/12/2010 06:44:18 »
Thanks Techmind. That's a lot of useful information.

When they do these calculations, do you happen to know what sort of assumptions they make regarding magnetic field cancellation? I'm also assuming the resultant magnetic field is, to some extent, a function of how well balanced the phases are and that the amount of imbalance has some impact on the numbers.
 

Offline Airthumbs

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« Reply #53 on: 28/12/2010 18:16:24 »
Having walked underneath high powered cables suspended between pylons, I have heard the buzzing noise they make. Personally I would not care to live within such close proximity to something that makes that kind of noise.  Also I would be very dubious of anyone that sais that there are no effects from living in such close proximity to these structures, the simple reason being it would be very easy to conduct research on this topic. 

When someone also sates that the emf in a house is stronger then that produced by these cables I would ask them to place a fluorescent light bulb anywhere in the home and see if it lights up by itself.   

As for the cables underground, well if they also emitted emf at the same strength that the overhead lines do then why don't site surveyors use fluorescent bulbs to detect where these cables are when they need to find there whereabouts?
 

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« Reply #54 on: 28/12/2010 18:55:30 »
Aaron:

You say- "Also I would be very dubious of anyone that sais that there are no effects from living in such close proximity to these structures, the simple reason being it would be very easy to conduct research on this topic." This is true and the research has been done over and over, and there are no affects.

I don't know what you are up to with the fluorescent lamps. Have you tried this around anything but a Tesla generator?

Steve
 

Offline Geezer

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« Reply #55 on: 28/12/2010 19:10:28 »
I don't know what you are up to with the fluorescent lamps. Have you tried this around anything but a Tesla generator?


You might even be able to produce a brief but similar effect by charging a party balloon. I've never actually tried it though.

EDIT: Come to think of it, I can cause an unpowered CFL to flash when I take off my clothes. (I wonder if it thinks I'm flashing it?  :o)

I wonder if it's possible to get some light out of a fluorescent tube simply be rubbing the glass at one end of the tube. A bit like the old "amber and cat's fur" experiment.

(More important information here http://uncyclopedia.wikia.com/wiki/Static_electricity)
« Last Edit: 28/12/2010 19:57:14 by Geezer »
 

Offline Airthumbs

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« Reply #56 on: 28/12/2010 19:54:46 »
Well I am way out of my depth on this one but I was making a reference about fluorescent lights and the picture of them all lit up underneath the electric pylons, is this fake then?

As for the research well I must take your word on that.  Would it be similar to the research done in America with regard to the Aluminium industry and Fluoride I wonder :-)
 

Offline Geezer

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« Reply #57 on: 28/12/2010 20:19:29 »
Aaron - Sorry - I added a bit more info to my post above.

You are quite right. Nobody wants to live anywhere near the things, and I can't say I blame them.

However, despite numerous studies, there does not seem to be any hard evidence that proves there is a connection between disease and HT power lines.

There are lots of ways to make fluorescent lights emit a bit of light without going anywhere near HT power lines. Humans and fluorescent light tubes are very different electrically. You and I have a rather low impedance (roughly similar to electric resistance) to the electric field produced by power lines, so the voltage produced across our bodies is very small.

Fluorescent tubes have a very high impedance, so the voltage across them (if they are vertical) can be enough to make them emit some photons. If you make a fluorescent tube a bit more like a human by providing any sort of conduction path between its ends (a bit of humidity might be quite sufficient) it won't light up under these conditions.
 

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« Reply #58 on: 28/12/2010 23:00:46 »
Sorry Geezer, that's not entirely right, in Sweden we have a lot of statistical studies over all sorts of things possible :) Mostly due to the way we use the system of 'person-nummer' allowing us to statistically treat a lot of information anonymously. We have a tradition of that kind of studies. I found two studies by a Google search. the first is from 1992 'närboendestudien' and another study of cancer for those working with it professionally. The first study looked at children's leukemia, adult leukemia and braintumors for people living less than 300 meters from 220 och 400 kV-high-voltage wires. They found a significant connection between where you lived, and children's leukemia when exposed over 0,2 μT  and later studies show the same for grown-ups at 0,2 μT per year. (Feychting och Ahlbom 1992, 1993).

The other study, for those that was working in electro magnetic fields, also from 1992-93, (Birgitta Floderus m.fl. 1992, 1993) showed similar results 0,2 – 0,3 μT. with a slightly weaker correlation between magnetic fields and brain tumors. There are also two Danish studies made that point in the same direction although not statistically proven/significant, Olsen (1993), Johansen (1998). But our Swedish studies are statistically impeccable :)

But it's not that popular a science, and the results are not popular with power companies and considering the telecom industry?
==

1994 an American-Finnish study was presented in where it was found a statistic correlation between Alzheimer and  having a electrical profession .. Sobel m.fl. (1995a, 1995b).. It have been followed by several other studies looking at other health problems as ALS (Avanipour m.fl. 1995), but it's hard to find the reasons, and you will need a lot of animal testing to prove it without doubt.

So I think I'll join LeeE here :)
« Last Edit: 28/12/2010 23:17:32 by yor_on »
 

Offline Geezer

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Is there any risk living under power lines?
« Reply #59 on: 29/12/2010 00:12:50 »
Yoron,

I would not argue with the Swedish data (and I'd have a bit of problem reading the papers  :D) but, how did they manage to discount other potential socioeconomic variables? I suspect the fact(?) that nobody really wants to live under HT lines could easily skew the data.

If there is a simple relationship between field strength and disease, it surely would not be very difficult to reproduce the effects with much more controlled experiments involving lab animals for example, or even farm animals both under, and not under HT lines. I wonder if there were any such studies?

Wasn't it Sweden that created a great stink about low frequency RF emissions from electronic equipment - particularly CRTs if I remember correctly? I'd be interested in seeing any follow-up studies that were conducted to prove the efficacy of the measures that all the CRT equipment manufacturers implemented to comply with the Swedish requirement.   
 

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« Reply #60 on: 29/12/2010 01:54:05 »
If I remember right they made some studies (Karolinska?) showing that the radiation could pass the brain-blood -barrier (cell phones), but what came of it I don't know? The problem with EM is that it's 'longterm effects' one will have to be on the lookout for. It's not like the amazing EM-man pops up, zapping you dead, if it was people would react, wouldn't they?:)

So we'll have to wait and see, also if there are few enough getting 'hit' it's not any immediate threat to our health. But still, there are statistical studies made finding a connection between people getting cancer as correlated to where they live, to a higher degree than the rest of the population. so there are some reason to think twice where you build your house, or chose to live.

Statistics can show you a 'trend' but as for defining how and why I think we need other types of tests. And no, I don't think they were biased. If anything, the money and power to bias (read advertising) I would expect to rest on the other side of the fence.
« Last Edit: 29/12/2010 02:01:02 by yor_on »
 

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« Reply #61 on: 29/12/2010 03:36:54 »
This issue provides a pretty good example of how science works when there is an issue that is potentially important. There are hundreds, perhaps more than a thousand, studies on how low frequency EMF affects health. Initially there was a flurry of small and poorly done studies that should be considered as preliminary. The press picks up the ones that report something alarming, while the ones that find nothing, or negative results, are ignored. Next some private agencies (e.g. power companies) and consumer advocates do a bunch of studies and make a big deal of what they find. Finally governmental agencies and government granted academics do large studies.

What finally happens is that agencies like, in the US, the National Science Foundation or the National Institutes of Health do large reviews of all the studies, decide which had adequate numbers of subjects, which had appropriate data collection and statistical methods, and review these. I have looked at some of these that have more than 700 references. It is these large evaluations of multiple well done studies that get to the truth of the matter. These studies find no effect, and furthermore find no known mechanism that could cause any problems.

The reason that many of these studies are all over the place, in that they find small positive and negative results, is that this is the expected statistical result when there actually is no effect. If at the beginning of this mess there had been just 10 studies, even with inadequate subject numbers and not so hot methods, that agreed that there was a strong effect there would have been no confusion and the next step would have been to find out what the mechanism is. It didn't happen.

Just finding a few studies is not adequate for making a claim. I suggest that anybody who wishes to see what the science actually says use Google Scholar which searches the scientific literature. If you try several searches with combinations of key words, such as, low frequency emf, power lines, cancer, or whatever in Google Scholar you will find the many studies that have been done. If you look for the most recent reviews done by responsible agencies, they will help you understand what has actually been found. Steve
 

Offline CliffordK

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« Reply #62 on: 29/12/2010 03:53:04 »
Remember that various types of radiation doses fall with the cube of the distance (3-D world we're living in).

I've got powerlines near my house...  about 50 feet in the air.  No buildings can be made within 50 feet of the center of the lines.  And, my house is about 100ft away.

I think I'd agree that more risk would be from stuff inside the house (microwaves, lights, wires, etc) rather than outside the house.

If I take volts/(distance cubed)...  I'm not quite sure what that give me..  But, say 120V/(3ft)³  =  4.4 V/ft³
10,000V/(100ft)³ = 0.01 V/ft³

I suppose I'm not considering amps and watts...  but, being 3 feet away from a 120V line in one's house is likely as dangerous if not more so than being 100 feet away from a 10,000V line outside.

There have been a lot of questions about whether it is wise to blast your ear with microwave transmissions from a cell phone.
 

Offline Geezer

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« Reply #63 on: 29/12/2010 06:14:53 »
Yoron,

I don't think there would be any bias in the Swedish data. It's just that I think other factors associated with the presence of HT lines but have nothing to do with EMR can easily skew the data.

For example, HT lines are most likely to coincide with lower cost housing, which could introduce lots of other factors that do increase the incidence of certain diseases. Some of these could be; less effective health care, poorer nutrition, more smoking, alcohol abuse, industrial pollution, home pollution, automobile pollution, poor ventilation, background radiation, heavy metal contamination, etc., etc.

In other words, if the HT lines were dummies that didn't actually carry any any current, but nobody knew that, would the data be any different? It might be interesting if we could run an experiment on that basis, but I can't imagine it would be possible to do it in Europe or the USA. Anyway, even if we could, I think so many people have been conditioned to think that HT lines do bad things, that it would be a complete waste of time.

(BTW, if you didn't already look at it, I encourage you to check out the link I posted above. It's quite entertaining.)



 

Offline Geezer

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« Reply #64 on: 29/12/2010 07:25:53 »
Here's one interesting paper from the BMJ

http://www.bmj.com/content/330/7503/1290.full.pdf?sid=5171d683-8c79-428a-b686-2ee1a96572e2

I found a couple of (what I thought were) very interesting statements in it.

"The finding that the increased leukaemia risk apparently extends so far from the the line is surprising in view of the very low level of magnetic field that could be produced by power lines at these distances."

It's only surprising if you have already assumed cause and effect - sheesh! What they fail to mention is that the the field strengths at these distances would be far weaker than the fields produced by all the other electrical wiring and equipment in any home.

"There is known to be a positive association between affluence and rates of childhood leukaemia."

Steps back in amazement! They use something called the Carstairs deprivation index to try to account for the socioeconomic differences, but, amazingly, when they apply that, it doesn't seem to make much difference to the results.

Hmmmm? Let's recap for a minute. There is no apparent correlation between distance from the power line (unless of course you live on the right side of town), and, it's well known that the incidence of this nasty childhood disease does correlate with wealth.

You don't suppose the only thing we can conclude is that the Carstairs deprivation index needs a serious tune up and we have wasted huge amounts of money that should have been spent on real research into childhood leukaemia?

The BMJ no less!! You might also wonder who the heck reviewed this paper.



« Last Edit: 29/12/2010 07:45:33 by Geezer »
 

Offline CliffordK

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« Reply #65 on: 29/12/2010 10:34:03 »
Here's one interesting paper from the BMJ

http://www.bmj.com/content/330/7503/1290.full.pdf?sid=5171d683-8c79-428a-b686-2ee1a96572e2
Interesting study. 

Are we supposed to conclude that the risk of CNS Brain Tumors is actually reduced for those living within 200m of the power lines?

Looking at the study, I think their fundamental error has to do with formulating the hypothesis AFTER analyzing the data.  I.E. making a hypothesis to match the data, rather than first making a hypothesis, then collecting data, and verifying that the data supports the previously formulated hypothesis.

 

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« Reply #66 on: 30/12/2010 16:29:23 »
Well the Swedish study had strict parameters as you can see. And my answer was to the proposal that there were no such studies. If you don't like them I'm sure you can translate them to English and point out what shortcomings you might see:)

The rest of the arguments are the type of arguments coming when we have different opinions I suspect :) If we look at climate nothing will persuade those denying the human aspect of our global warming. And here I'm just stating that I found LeeE:s approach the one that suits me. I'm not stating that we have a proven effect 'beyond doubt'. But it's perfectly reasonable to me. We're all 'electromagnetic' I think :)
==

Before anyone think that I think it's terribly dangerous to live close. No, I do not. It's very few that seems to get any effect from EM radiation. And there might as Geezer points out, be other effects needed for it to become 'dangerous'. That's the trouble with all statistics, they might tell you that 'somethings happening' but they don't specify why and how. That's where your deductions come in, and other types of research.

Also, if we look at how we treated other health issues like the London smog, cigarettes etc. Then there is a very long 'turnaround time' the closer the issue is related to the 'economy'. But as we are a shortsighted species we seem to forget that as soon as we are there. Humans really seems to live in the proverbial 'N0W', don't they?
« Last Edit: 30/12/2010 16:50:37 by yor_on »
 

Offline Geezer

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« Reply #67 on: 30/12/2010 17:14:30 »
Yoron,

It's OK to say that, because power lines are unnatural sources of EMR, they could possibly be harmful, so it's best to avoid them. However, there are many powerful sources of EMR in all homes, even when they are miles away from overhead power lines. It makes no sense to treat overhead lines any differently than all the other sources. The only real difference is that power lines are big and ugly. The other stuff is more or less invisible.

I'm sorry, but I firmly believe this is simply a case of mass hysteria and paranoia.

There must be a name for an irrational fear of overhead power lines. Anybody know what it is?
 

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« Reply #68 on: 30/12/2010 17:38:20 »
Yep, I agree. It all depend on their shielding how much radiation you will have. And with the exponential growth of cellphones and the antennas/amplifiers needed to boost the signals we have increased the radiation around us. It's an 'experiment', but seen from a longer point of view the only thing needed for procreate humanity is that we live so long that we can raise some kids. Thats why, even under the worst circumstances possible, humanity still comes through. It's not difficult to see, and I think we all know this.

And life itself is a risk-taking, always. You take a risk just stepping outside your door, or waking up, or even sleeping.
Now, wasn't that what Bilbo used to say too?

"He used often to say there was only one Road; that it was like a great river: its springs were at every doorstep, and every path was its tributary. "It's a dangerous business, Frodo, going out of your door," he used to say. "You step into the Road, and if you don't keep your feet, there is no knowing where you might be swept off to. Do you realize that this is the very path that goes through Mirkwood, and that if you let it, it might take you to the Lonely Mountain or even further and to worse places?" He used to say that on the path outside the front door at Bag End, especially after he had been out for a long walk.' "
 

Offline Geezer

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« Reply #69 on: 30/12/2010 18:29:45 »
You know, I think the really sad thing is that it's quite easy to conclude from all of this that there is a stronger correlation between childhood leukaemia and wealth than previously recognized. If some of the money that's being spent on trying to prove there is a problem with HT lines is used to isolate the specific environmental factors that increase the risk of childhood leukaemia, a lot of young lives might benefit.

Of course, that won't benefit journalists and lawyers.
« Last Edit: 31/12/2010 07:50:46 by Geezer »
 

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« Reply #70 on: 31/12/2010 16:22:32 »
Geezer, I strongly agree with your general sentiment, but children of families with low socioeconomic status (SES), especially in the US (relative to other developed nations), are subject to all kinds of problems ranging from high infant mortality to higher rates of every kind of childhood disease. I am not saying that finding a way to reduce leukemia is a bad idea, I am saying that this is a more generalized problem. Steve
 

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« Reply #71 on: 31/12/2010 22:49:06 »
Undoubtedly some of the "Modern Conveniences" that are supposed to be safe actually cause long-term health problems. 

In any one place, we are being bombarded by hundreds of radio and TV stations, as well as cell phone, cordless phone, and WIFI signals.  We stick cell phone transmitters next to our ears, and some people even attach Bluetooth transmitters to their ears. 

We have the high power main transmission lines that are somewhat isolated from people, but also an entire distribution network of lower energy power lines that are much closer.  And, if you don't see them in your neighborhood, that is probably because you're walking on them.

We've got microwaves, ovens, electric motors, etc in houses.

One might be able to study differences between "Mainstream Americans" and Amish, for example.  But, there undoubtedly are many confounding variables, and they still are subject to the radio and tv signals.  What about the Russian Reindeer Herders?

Yet, I fear that if one concludes that "technology kills", one would also come to another conclusion that the lack of technology is deadly noting that some of the least industrialized nations (Zambia, Angola, and Swaziland) have a life expectancy of about HALF that of the industrialized nations.
 

Offline Geezer

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« Reply #72 on: 31/12/2010 23:35:56 »
To your point Clifford, I read the other day that 90% of the World's human population live within range of a cell phone tower. I was quite surprised to learn that.

 

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« Reply #73 on: 01/01/2011 02:46:43 »
To your point Clifford, I read the other day that 90% of the World's human population live within range of a cell phone tower. I was quite surprised to learn that.

A little off subject, but truthfully US cellphone technology is pretty crude compared to that in the rest of the world.  People in some countries use their cell phones like credit cards, and do a significant amount of online banking with their phones.

Tying it back in though  ;), one has to assume the cell phone technology has been tested with rats and such.  But, it is hard for a few month or few year study in animals to represent the long-term, and multi-factorial impact on humans. 

I'd be much more concerned with holding microwave transmitters next to my ear than stray EM fields from high voltage power lines. 

The solution, of course, would be to use local power generation and 12VDC or 24VDC.  I groan about the idea of spending millions or billions of dollars for power distribution networks in 3rd world nations when it might be better to invest the money in solar and other local power generation/distribution technologies.
 

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« Reply #74 on: 01/01/2011 03:16:21 »
As there is no known mechanism by which electric fields with a frequency less than that of ultra violet light can have any affect on living tissue, and there doesn't appear to be any epidemiological evidence that it does, what is the concern. If the effect is so hard to detect, please explain how your concern re EMF from microwaves and 60 cycle is a more important concern than sending your kids to school on a school bus.
 

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