Are Cell Towers/Wifi Harmless?
December 17, 2009 7:49 PM Subscribe
So cell towers are being installed next to a school that's near mine. Parents there are concerned about this, and also about the presence of wifi networks in schools. They cite research promulgated by a Magda Havas. I know hers is a minority viewpoint- but is it fairly described as 'crackpot'? Do parents have legitimate concerns over these issues?
The latest legitimate studies show no definable evidence of any link, and there has been no statistical increase in brain cancers in the last 20 years - contemporaneous with a huge increase in cell phone usage.
http://www.wikio.com/article/study-link-cell-phone-brain-cancer-152106227
posted by Dipsomaniac at 8:29 PM on December 17, 2009
http://www.wikio.com/article/study-link-cell-phone-brain-cancer-152106227
posted by Dipsomaniac at 8:29 PM on December 17, 2009
No. I presume most of these parents use mobile phones? The microwaves shooting into the side of your head from a phone are orders of magnitude greater than what's coming off towers, and they don't seem that bad anyway. Might as well complain about someone's aura.
posted by smoke at 8:33 PM on December 17, 2009 [1 favorite]
posted by smoke at 8:33 PM on December 17, 2009 [1 favorite]
Completely and utterly batshit insane. Also, what Dipso said.
posted by chrisamiller at 8:47 PM on December 17, 2009
posted by chrisamiller at 8:47 PM on December 17, 2009
Yes "crackpot". No "legitimate concerns".
posted by Chocolate Pickle at 8:51 PM on December 17, 2009
posted by Chocolate Pickle at 8:51 PM on December 17, 2009
Crazy. Absolutely crackpot crazy.
The electric motor in their Prius generates a more harmful electric flux than the cell tower does.
posted by Netzapper at 8:52 PM on December 17, 2009 [1 favorite]
The electric motor in their Prius generates a more harmful electric flux than the cell tower does.
posted by Netzapper at 8:52 PM on December 17, 2009 [1 favorite]
It's pretty much total bunk.
If you're worried about cancer due to EM radiation, you should only be worried about ionizing radiation - that's the sort that can knock electrons off of biological molecules in your cells and muck things up. Luckily, ionizing radiation starts at around 1 eV. That's 200,000 GHz. Cell phones and similar wireless technology operate below 10 GHz. That's 10,000 orders of magnitude too weak to mess with your DNA.
The only reason it MIGHT be legitimate to worry about cell phones themselves is that while microwaves from your cell phone can't directly mess with your cellular chemistry, they do cause a MINUTE amount of heating, which could conceivably cause a biological effect. But there isn't ANY reputable evidence demonstrating any negative effect, and several studies that failed to demonstrate any effect.
As for the "EM sensitivity" stuff, I personally think it's mostly nonsense, but it's a little harder to debunk on first principles. There's no question that the brain is sensitive to external magnetic fields, though clinical studies of such effects usually involve magnetic pulses with magnitudes of several Tesla (many many times the field strength of anything coming from a cell tower). The idea of neurological effects from a nearby cell tower is slightly more credible, but the idea of long-term harm is still pretty unlikely. Besides, the power you're transmitting directly into your brain is much greater than anything you'd be getting from a nearby cell phone tower.
Another thing to consider - if the children in this school are going to use cell phones, their cell phones will emit much less EM power into their brains if they're in an area with good coverage - i.e. near a cell tower! So for your average teenager with a cellphone glued to their ear, they'll probably get a much LOWER dose of microwave radiation if they build a cell tower nearby!!
posted by Salvor Hardin at 8:54 PM on December 17, 2009 [8 favorites]
If you're worried about cancer due to EM radiation, you should only be worried about ionizing radiation - that's the sort that can knock electrons off of biological molecules in your cells and muck things up. Luckily, ionizing radiation starts at around 1 eV. That's 200,000 GHz. Cell phones and similar wireless technology operate below 10 GHz. That's 10,000 orders of magnitude too weak to mess with your DNA.
The only reason it MIGHT be legitimate to worry about cell phones themselves is that while microwaves from your cell phone can't directly mess with your cellular chemistry, they do cause a MINUTE amount of heating, which could conceivably cause a biological effect. But there isn't ANY reputable evidence demonstrating any negative effect, and several studies that failed to demonstrate any effect.
As for the "EM sensitivity" stuff, I personally think it's mostly nonsense, but it's a little harder to debunk on first principles. There's no question that the brain is sensitive to external magnetic fields, though clinical studies of such effects usually involve magnetic pulses with magnitudes of several Tesla (many many times the field strength of anything coming from a cell tower). The idea of neurological effects from a nearby cell tower is slightly more credible, but the idea of long-term harm is still pretty unlikely. Besides, the power you're transmitting directly into your brain is much greater than anything you'd be getting from a nearby cell phone tower.
Another thing to consider - if the children in this school are going to use cell phones, their cell phones will emit much less EM power into their brains if they're in an area with good coverage - i.e. near a cell tower! So for your average teenager with a cellphone glued to their ear, they'll probably get a much LOWER dose of microwave radiation if they build a cell tower nearby!!
posted by Salvor Hardin at 8:54 PM on December 17, 2009 [8 favorites]
Besides, the power you're transmitting directly into your brain
Erm, I meant when you talk on your cell phone.
posted by Salvor Hardin at 8:55 PM on December 17, 2009
Erm, I meant when you talk on your cell phone.
posted by Salvor Hardin at 8:55 PM on December 17, 2009
The wavelength of cell phone radiation is about one foot.
Now, you could go into a parent-teacher meeting making an argument about ionization energy and penetration depths - and it would be great if you would - but I think a big part of the fear is based around the word "radiation." People don't know much E&M, and automatically associate the word with nuclear bombs and cancer, and not with visible light and radio waves. The amount of ignorance among doctors on this topic is staggering. I taught a physical sciences class for pre-meds class once, and made a point of having this very conversation with them, because most of them were in the "better err on the side of caution" camp, and wouldn't have been able to explain to their future concerned patients that it's physically impossible for cell-phone-frequency waves (or microwave ovens!) to ionize you.
posted by you're a kitty! at 9:14 PM on December 17, 2009 [3 favorites]
Now, you could go into a parent-teacher meeting making an argument about ionization energy and penetration depths - and it would be great if you would - but I think a big part of the fear is based around the word "radiation." People don't know much E&M, and automatically associate the word with nuclear bombs and cancer, and not with visible light and radio waves. The amount of ignorance among doctors on this topic is staggering. I taught a physical sciences class for pre-meds class once, and made a point of having this very conversation with them, because most of them were in the "better err on the side of caution" camp, and wouldn't have been able to explain to their future concerned patients that it's physically impossible for cell-phone-frequency waves (or microwave ovens!) to ionize you.
posted by you're a kitty! at 9:14 PM on December 17, 2009 [3 favorites]
Salvor Hardin: "That's 10,000 orders of magnitude too weak to mess with your DNA."
10,000 times -- four orders of magnitude.
/pedant
posted by alexei at 10:36 PM on December 17, 2009 [1 favorite]
10,000 times -- four orders of magnitude.
/pedant
posted by alexei at 10:36 PM on December 17, 2009 [1 favorite]
Short opinion: it's pretty much a crackpot worry.
Longer rambling answer: There've been bunches of worries and bunches of studies on this subject as cell phones have proliferated, and before that, microwaves, and before that, radar; so this is reasonably well-studied territory. As far as I know, the only known, accepted mechanism for injury from radiation in the 1-2 GHz band is thermal: the radio waves heat your tissue, and this injures you. You can get cataracts from a malfunctioning microwave, for example. However, that takes many orders of magnitude more intensity than you'll get from a nearby cell tower.
(Quick worst-case calculation: A cell tower might have an EIRP of 3kW, so if your kid is 200 ft. away in the center of the beam (unlikely, since they don't waste the high power part of the pattern on nearby areas!), they'll receive ~ 7µW/cm^2. In practice you'll get a lot less than that. From a cell phone 3 cm away radiating 20 mW (the lowest level a GSM phone can emit), and assuming that the phone radiates 90% of its radiation away from the user, you're still getting ~ 10µW/cm^2. In practice you'll get more than that.)
Aside from known effects, there's the vague, mostly-unsupported notion that the pulsed nature of cell phone communications could have some sort of effect via some unknown mechanism. Of course, since the effect is unspecified, it's hard to disprove this idea, but numerous studies have failed to turn up anything reliable.
Here is a (slightly out of date but) well annotated FAQ on the subject.
posted by hattifattener at 10:56 PM on December 17, 2009
Longer rambling answer: There've been bunches of worries and bunches of studies on this subject as cell phones have proliferated, and before that, microwaves, and before that, radar; so this is reasonably well-studied territory. As far as I know, the only known, accepted mechanism for injury from radiation in the 1-2 GHz band is thermal: the radio waves heat your tissue, and this injures you. You can get cataracts from a malfunctioning microwave, for example. However, that takes many orders of magnitude more intensity than you'll get from a nearby cell tower.
(Quick worst-case calculation: A cell tower might have an EIRP of 3kW, so if your kid is 200 ft. away in the center of the beam (unlikely, since they don't waste the high power part of the pattern on nearby areas!), they'll receive ~ 7µW/cm^2. In practice you'll get a lot less than that. From a cell phone 3 cm away radiating 20 mW (the lowest level a GSM phone can emit), and assuming that the phone radiates 90% of its radiation away from the user, you're still getting ~ 10µW/cm^2. In practice you'll get more than that.)
Aside from known effects, there's the vague, mostly-unsupported notion that the pulsed nature of cell phone communications could have some sort of effect via some unknown mechanism. Of course, since the effect is unspecified, it's hard to disprove this idea, but numerous studies have failed to turn up anything reliable.
Here is a (slightly out of date but) well annotated FAQ on the subject.
posted by hattifattener at 10:56 PM on December 17, 2009
That's a lot of well-produced crazy. Ask the nut-jobs to measure the "radiation" they are talking about. Also, dirty electricity. HA!
Also, this is complete bat-shittery. In the first place, the ground is the source of electrons. In the second place, the ground is always the "return path" for generated power. There is no neutral wire until you get to the endpoint near the house.
posted by gjc at 11:16 PM on December 17, 2009
Also, this is complete bat-shittery. In the first place, the ground is the source of electrons. In the second place, the ground is always the "return path" for generated power. There is no neutral wire until you get to the endpoint near the house.
posted by gjc at 11:16 PM on December 17, 2009
There was a related question on Ask MeFi regarding RF exposure from cell phone towers a couple of years back. You might find something useful in that thread.
posted by RichardP at 12:06 AM on December 18, 2009
posted by RichardP at 12:06 AM on December 18, 2009
It is not the tower people should worry about but the little transmitters that they carry with them. Most of the research into the effects has some pretty significant flaws. Including the interphone study.
I have seen credible evidence on both sides of the argument, enough to not throw out the whole idea as "junk" science.
posted by psycho-alchemy at 1:07 AM on December 18, 2009
I have seen credible evidence on both sides of the argument, enough to not throw out the whole idea as "junk" science.
posted by psycho-alchemy at 1:07 AM on December 18, 2009
I was at a presentation by Magda Havas in Toronto in January 2007. She advocated 'lining your hat with metallic material' if you used your cellphone a lot. Yes, MeFi's favourite headgear was mentioned, in all seriousness.
gjc, while the language is unusual, ground rise is a known problem in stock handling. Whether it's due to faulty practice inside the barn or outside on the pole, cows are really not that keen on being the ground return for a few volts.
(oh and, eponysterical!)
posted by scruss at 5:14 AM on December 18, 2009
gjc, while the language is unusual, ground rise is a known problem in stock handling. Whether it's due to faulty practice inside the barn or outside on the pole, cows are really not that keen on being the ground return for a few volts.
(oh and, eponysterical!)
posted by scruss at 5:14 AM on December 18, 2009
If these kind of waves do cause problems, we're all screwed. THEY ARE EVERYWHERE.
posted by cp7 at 7:34 AM on December 18, 2009
posted by cp7 at 7:34 AM on December 18, 2009
per houstonian's post about parents complaints (possibly) being responsible for the removal of a cell tower. These are the same people that will complain long and loud to their cell company, the local paper and on whatever blog they write that their shiny new smartphone doesn't have any service near their kids school.
Yes, batshit insane just about covers it. I hope the same complainers are getting rid of the microwave oven that they have in their kitchens.
posted by 543DoublePlay at 8:10 AM on December 18, 2009
Yes, batshit insane just about covers it. I hope the same complainers are getting rid of the microwave oven that they have in their kitchens.
posted by 543DoublePlay at 8:10 AM on December 18, 2009
This thread is closed to new comments.
posted by Houstonian at 8:05 PM on December 17, 2009