Radiation Chart

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Varion
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Radiation Chart

Postby Varion » Mon Mar 21, 2011 11:56 pm UTC

I've searched multiple topics on the forum and haven't found one regarding the chart. I think it's an awesome chart except for one quibble.

"A cell phones transmitter does not produce ionizing radiation and does not cause cancer."

The world health organization is due to publish a link between long term cell phone use and brain cancer. While this may not be due to ionizing radiation, it's improper at this point to state that it does not cause cancer. I think ethically it would be best to state that it does not produce cancer by way of ionizing radiation.

As my uncle died from brain cancer coincidentally on the same side he used his cell phone, I would be greatful if you would at least consider changing the chart.

Edit to add link: http://blog.xkcd.com/2011/03/19/radiation-chart/ -Hawk

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 12:00 am UTC

As my uncle died from brain cancer coincidentally on the same side he used his cell phone, I would be greatful if you would at least consider changing the chart.



a) there was a 1/2 chance of that happening anyways.
b) there's something that correlation fails to imply, but I forgot what it was momentarily...
c) I'm sorry for your loss.
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Re: Radiation Chart

Postby Jakell » Tue Mar 22, 2011 1:12 am UTC

I am sorry for your loss, but this is a basic physics question. From Wikipedia, radiation can be split into two varieties, ionizing and non-ionizing. Ionizing radiation, when it encounters chemicals (like DNA) can cause chemical changes in the molecules; breaking chemical bonds, deleting parts of the DNA sequence, activate or inactivate genes in chromosomes, or even break apart chromosomes entirely. It takes a certain amount of energy to make these changes happen, somewhere in the vicinity of 3+ eV (electron volts, 4*10^-19 Joules ish). Visible light has an average energy of 2 eV, but up at the violet end you reach about 3 eV, and UV light (the starting to be dangerous stuff that gives you sunburns) runs from 4 eV and up. This light has enough energy to make chemical reaction happen, to do chromosomal damage, and to cause cancer. My 1W blue laser comes with a skin-hazzard warning, because the ridiculous number of photons each have a slight chance of causing chemical changes to my DNA, it would be worse if it was a UV laser, and far safer if it was IR. Anyway, this is the stuff we refer to as ionizing radiation, the light which can start messing with chemical bonds.

Light that has less energy then this stuff is non-ionizing radiation. It can not break chemical bonds. It can not cause chromosomal damage. It can not cause cancer. The photon energy of microwaves is on the order of micro-electron volts, or millionths of an electron volt. There is simply not enough energy to do anything damaging to molecules. What microwaves do is, to a rough approximation, vibrate water molecules really well, causing them to heat surrounding material. They can be very good at this, and there is measurable heating from using cell phones. My comparison, though, is that you get more heating holding a Labrador puppy to the side of your head then you get using a cell phone, and you have the risk of the claws and tongue to deal with. Not cancer. We actually use microwaves in hospitals to treat emergency cases of Hypothermia, the deep tissue heating can help save limbs from fairly severe frostbite. Microwaves can also cause some very cool Auditory Illusions, but again, no cancer there.

With a little google-fu, here is a 2009 Who Article which states:
The study found no indication of higher brain tumor risk among persons who had used hand-held cell phones compared with those who had not used them. More importantly, there was no evidence of increasing risk with increasing years of use or average minutes of use per day, nor did brain tumors among cell phone users tend to occur more often than expected on the side of the head on which the person reported using their phone. Specifically, there was no indication of increased risk associated with use of a cell phone for 1 hour or more per day, for 5 or more years, or for cumulative use of more than 100 hours. These findings pertain to all three tumor types considered (glioma, meningioma, and acoustic neuroma).


The WHO is going to be publishing further studies which look for a link between cancer and cell phone use, but I can pretty much guarantee that there will be no association between cell phone use and cancer. Again, cancer depends on the photoelectric effect, and Einstein back in 1905, explained pretty conclusively that if the photons do not have enough energy to cause an atomic transition, then they will not.

Sorry again for your loss, but the physics is very plain and simple. Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you. The chemicals on the inside, however, are a different matter, but that is more of a chemistry issue.
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Re: Radiation Chart

Postby ++$_ » Tue Mar 22, 2011 1:16 am UTC

The takeaway message here is that you should not apply a Labrador puppy to the side of your head (at least, not over the long term).

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Re: Radiation Chart

Postby lowlypeon » Tue Mar 22, 2011 1:34 am UTC

There have been articles that the WHO is "about to publish a study showing a link between mobile phone use and cancer" since 2009. Mostly on questionable websites like naturalnews.com-- Hasn't happened, and I don't think it's going to.

Their stance at this point, as reported on www.who.int is:

A number of studies have investigated the effects of radiofrequency fields on brain electrical activity, cognitive function, sleep, heart rate and blood pressure in volunteers. To date, research does not suggest any consistent evidence of adverse health effects from exposure to radiofrequency fields at levels below those that cause tissue heating. Further, research has not been able to provide support for a causal relationship between exposure to electromagnetic fields and self-reported symptoms, or “electromagnetic hypersensitivity”.

The international pooled analysis of data gathered from 13 participating countries found no increased risk of glioma or meningioma with mobile phone use of more than 10 years. There are some indications of an increased risk of glioma for those who reported the highest 10% of cumulative hours of cell phone use, although there was no consistent trend of increasing risk with greater duration of use. Researchers concluded that biases and errors limit the strength of these conclusions and prevent a causal interpretation.


Obviously it's hard to say 100% that long-term exposure might not have some unexpected effect due to lack of good data on mobile phone use longer than 15-20 years.

Sorry your uncle died from brain cancer, but evidence to date does not show that there is a statistical correlation.

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 1:53 am UTC

Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.
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Re: Radiation Chart

Postby alexh123456789 » Tue Mar 22, 2011 2:01 am UTC

sourmìlk wrote:
Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.


true, but the difference between ionizing and non-ionizing radiation isn't the speed, it's the wavelength, and the Doppler effect works on light the same way it works on sound.

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 2:05 am UTC

alexh123456789 wrote:
sourmìlk wrote:
Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.


true, but the difference between ionizing and non-ionizing radiation isn't the speed, it's the wavelength, and the Doppler effect works on light the same way it works on sound.


Oh, forgot about that.
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Radiation damage

Postby JoeBloggs » Tue Mar 22, 2011 2:15 am UTC

Is radiation damage a linear function of exposure in SV?
eg someone exposed to 4 Sv is twice as screwed as someone exposed to 2 Sv (over the same time interval)

Over-simple example: sunburn can go from bad to much worse, with not that much addtl time exposed.

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Re: Radiation Chart

Postby Shadow2Lead » Tue Mar 22, 2011 2:38 am UTC

sourmìlk wrote:b) there's something that correlation fails to imply, but I forgot what it was momentarily...


Correlation does not imply causation. - http://en.wikipedia.org/wiki/Correlation_does_not_imply_causation

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 2:39 am UTC

Shadow2Lead wrote:
sourmìlk wrote:b) there's something that correlation fails to imply, but I forgot what it was momentarily...


Correlation does not imply causation. - http://en.wikipedia.org/wiki/Correlatio ... _causation


I was being facetious, I knew what correlation didn't imply.
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Re: Radiation Chart

Postby The Reaper » Tue Mar 22, 2011 3:21 am UTC

sourmìlk wrote:
Shadow2Lead wrote:
sourmìlk wrote:b) there's something that correlation fails to imply, but I forgot what it was momentarily...


Correlation does not imply causation. - http://en.wikipedia.org/wiki/Correlatio ... _causation


I was being facetious, I knew what correlation didn't imply.

YOU LIE! :3

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 3:25 am UTC

The Reaper wrote:
sourmìlk wrote:
Shadow2Lead wrote:
sourmìlk wrote:b) there's something that correlation fails to imply, but I forgot what it was momentarily...


Correlation does not imply causation. - http://en.wikipedia.org/wiki/Correlatio ... _causation


I was being facetious, I knew what correlation didn't imply.

YOU LIE! :3


This is the XKCD fora, in case you didn't remember ;)
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Re: Radiation Chart

Postby Soralin » Tue Mar 22, 2011 3:36 am UTC

sourmìlk wrote:
alexh123456789 wrote:
sourmìlk wrote:
Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.


true, but the difference between ionizing and non-ionizing radiation isn't the speed, it's the wavelength, and the Doppler effect works on light the same way it works on sound.


Oh, forgot about that.

Although, if you have a cell phone flying towards you at high relativistic speeds, you might have some more immediate concerns to deal with first. :)

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Re: Radiation Chart

Postby The Reaper » Tue Mar 22, 2011 3:47 am UTC

Soralin wrote:Although, if you have a cell phone flying towards you at high relativistic speeds, you might have some more immediate concerns to deal with first. :)
But not for much longer.

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Re: Radiation Chart

Postby boradis » Tue Mar 22, 2011 4:18 am UTC

You (Randall) say you want to clear up misconceptions, but then you say:

"I’m not an expert in radiation and I’m sure I’ve got a lot of mistakes in here ..."

Don't science and due diligence require that you run this by someone like a radiation oncologist and have them sign off on it before posting?

This isn't an Internet communities map.

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Re: Radiation Chart

Postby drkslvr » Tue Mar 22, 2011 4:46 am UTC

The Reaper wrote:
Soralin wrote:Although, if you have a cell phone flying towards you at high relativistic speeds, you might have some more immediate concerns to deal with first. :)
But not for much longer.

Honestly, you probably wouldn't have long enough to be concerned in the first place. XD
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Re: Radiation Chart

Postby phlip » Tue Mar 22, 2011 5:51 am UTC

What to do if you have a mobile phone flying towards you at relativistic speeds: think of how lucky you are that life has been good to you so far. Alternatively, if life hasn't been good to you so far (which, given your current circumstances, seems more likely): think of how lucky you are that it won't be bothering you much longer.

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Re: Radiation Chart

Postby ++$_ » Tue Mar 22, 2011 5:57 am UTC

Or, consider yourself lucky, because you are about to die in a totally new way.

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Re: Radiation Chart

Postby KingofMadCows » Tue Mar 22, 2011 6:18 am UTC

There was a study done a while ago that exposed mice genetically engineered to develop beta-amyloid plaques to cell phone radiation for two hours a day. It prevented cognitive impairment in the mice. In fact, their performance on memory tests was better than normal mice of the same age. Assuming it has the same effect on humans, cell phones might actually help you live longer.

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Re: Radiation Chart

Postby Sourire » Tue Mar 22, 2011 6:19 am UTC

boradis wrote:You (Randall) say you want to clear up misconceptions, but then you say:

"I’m not an expert in radiation and I’m sure I’ve got a lot of mistakes in here ..."

Don't science and due diligence require that you run this by someone like a radiation oncologist and have them sign off on it before posting?

This isn't an Internet communities map.

And his graphic wasn't published in an academic journal. It was posted freely and with diligent disclaimers. I see no reason to fault him for admitting his limits-it's far more scientific that way.
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Re: Radiation Chart

Postby legopelle » Tue Mar 22, 2011 8:39 am UTC

phlip wrote:What to do if you have a mobile phone flying towards you at relativistic speeds: think of how lucky you are that life has been good to you so far. Alternatively, if life hasn't been good to you so far (which, given your current circumstances, seems more likely): think of how lucky you are that it won't be bothering you much longer.

Best quote today. :D
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Re: Radiation Chart

Postby tobbel » Tue Mar 22, 2011 10:00 am UTC

I noticed an error in the chart (not Randalls fault as it is wrong on wikipedia also, and I made a note on the talk page for now), but the mammogram dose used in the chart is too high. This is because that it is not given as the effective dose (ie whole body equivalent dose) but rather in the equivalent dose, which unfortunately also uses the sievert-unit. The source is this article http://www.nejm.org/doi/full/10.1056/NEJMra072149 which clearly states “organ doses”. That is, it is the breasts that receive 3 mSv, and the effective dose is instead 3 x 0.05 mSv = 0.15 mSv and this should be the value that is used for comparisons. See http://en.wikipedia.org/wiki/Effective_dose and http://en.wikipedia.org/wiki/Sievert.

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Re: Radiation Chart

Postby Technical Ben » Tue Mar 22, 2011 11:05 am UTC

That is also another thing about radiation, it's difficult to quantize in simple terms. Just like heat. Touching a hot hob for less than 1 second at 100 degrees* might only singe the dead skin and your unharmed. Touching it for any longer than that and your in trouble. Going in a cold room at -5 for an hour will mean you need to wrap up warm. Have your body temperature drop to -5 and your in trouble.
So, just showing a dose, can be difficult to visualise or explain the dangers. Just posting a temperature chart with "safety" levels would be confusing. Many people use fires that are hundreds of degrees hot, yet suffer no harm. Radiation can be similar, how long and how high a dose. Maybe more variables. I'm no expert myself. But even that chart is confusing on how background radiation can be more than some of the other exposures (such as a power plant?).

Mobile phones offer no more radiation than a banana. They emit "radiation" that is similar to that of a candle, and less than that of a radioactive isotope. The problem is, most people put radiation into one group, when there is more than one type. One way to explain it is that everything gives off radiation. But some things give off so much that it is dangerous. Mobile phones only give off as much as other everyday items.

(Oh, but it was cool to see the CRT/TV listed on the chart there. I always wondered if a broken/overloaded one of those could cause eye cancer. :O )

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Re: Radiation Chart

Postby Endless Mike » Tue Mar 22, 2011 12:49 pm UTC

sourmìlk wrote:
Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.

I once had someone tell me that Blu-Ray took so long to develop because blue light is too slow. He then linked me to an article about red shift. I facepalmed.

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Re: Radiation Chart

Postby sourmìlk » Tue Mar 22, 2011 2:41 pm UTC

Endless Mike wrote:
sourmìlk wrote:
Unless you and the cell phone are traveling at relativistic speeds at eachother, the photons given off by the cell phone are not going to harm you.


Speed wouldn't do anything as Einstein's Special Theory of Relativity states that light travels at the same speed compared to you regardless of your reference frame.

I once had someone tell me that Blu-Ray took so long to develop because blue light is too slow. He then linked me to an article about red shift. I facepalmed.


Wow. Seriously? I don't even... but red shift has nothing... and the speed difference would be...

the fuck?
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Re: Radiation Chart

Postby Endless Mike » Tue Mar 22, 2011 2:50 pm UTC

Basically.

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Re: Radiation Chart

Postby savanik » Tue Mar 22, 2011 3:52 pm UTC

For clarification on units and such:

1 'click' on an old-style Geiger counter equals one count.
1000 counts is (approximately) equal to one millirad per hour.
One millirad is about 10 milliSieverts of exposure.

Based on the chart, 100 milliSieverts is enough to cause statistically measurable rates of cancer, long-term. That would be standing next to a source of 10,000 counts for 1 hour.

For what it's worth, acute radiation poisoning symptoms typically begins at 1 Sievert. 100,000 counts would cause this in one hour.

Counts are actual radioactive activity (or becquerels in SI terms, see conversion tables elsewhere).
Rads are actual exposure (activity over time).
Sieverts are equivalent exposure doses (exposure actually absorbed by human tissue).

These numbers may also vary, depending on the kind of radiation (gamma vs. alpha being a big one), and what tissue specifically is exposed. Overall, though, that should be a decent approximation from going to 'click of Geiger counter' to 'how much exposure is that'.

Many modern Geiger counters will directly give you exposure rates in mSv/hr. Now I want to get a Geiger counter and put a banana on it.
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Re: Radiation Chart

Postby mosc » Tue Mar 22, 2011 9:22 pm UTC

Varion wrote:As my uncle died from brain cancer coincidentally on the same side he used his cell phone

I'm going out on a limb here and say that it was the same side as the side of the car he drove on? There's a link between the side of the body where cancer develops and which side you drive on, particularly in males. Why? We roll the windows down and the sun blasts us with radiation on one side more than the other. There's also a very large chance of coincidence here, as others have mentioned.

People don't often understand it but we humans are bombarded by radiation from a massive thermonuclear explosion called the Sun. It kicks out a lot of stuff. We often think of the sun as a benevolent giver of life which it in many ways is, but it's also a death dealing ball of fury. It may be a lot further away from you than your cell phone, but it also kicks out several billion billion times more energy, and not all in a nice safe friendly part of the EM spectrum like your cell phone does either.

I'll also give you the EM201 explanation of how RF affects the human body. Let me start by saying I'm sorry for your loss and if any of this comes across as flippant, it's not intended to belittle what you are going through:

Basically, electro-magnetic radiation (EM for short) is a spectrum spanning lots of different frequencies. Some people describe it based on wavelength, this is equivalent. Frequency and wavelength are reciprocals: If you know one, you know the other 100% of the time.
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At the high end of the spectrum, you have very high energy density photons like gamma rays which are very dangerous even in small doses. Fortunately, it takes some extreme astrological events to generate these things. X-rays are far less intense, but still dangerous. Most people are familiar with the dangers of x-rays and the way to protect yourself. What a lot of people don't know is why x-rays are valuable. Their high frequency (or low wavelength if you prefer) allows them to pass through the skin, but the frequency is still low enough where they are absorbed by the denser material (bones mostly, but also organs etc). This allows doctors to "see through" your skin. Basically, they see a picture of your density, so they can look at your bones.

Visible light is in the middle of the spectrum, and still has some penetration capability (glass) but is generally absorbed. When EM is absorbed, it basically creates heat. The sunlight gets absorbed by the earth, or your skin, and heats us up. Higher frequency light (particularly UV light) is dangerous, but still gets absorbed by the skin. This is why UV light causes skin cancer, not brain cancer. It's still dangerous, but it gets absorbed.

As you move down the spectrum into microwaves, absorption starts to become difficult, but not impossible. When microwaves are absorbed, they also create heat. This is how your microwave oven works. Some things take longer to cook in a microwave than others because they are less absorbent. Water is pretty good at soaking up microwaves though as is skin (you'd know if you ever tired cooking chicken in a microwave). Metal absorbs some microwaves, but actually starts to REFLECT them as you move lower in the spectrum as well. Microwaves are shielded by metal cages both to keep the microwaves inside but mostly work through reflecting the waves back at your food. It wouldn't be very efficient if the microwave simply blasted all that heat into the cage, now would it?

Radio frequencies are even lower in frequency, and even less intense. They reflect off of most dense material and are difficult to absorb. They aren't a health risk like higher energy light and can't even really COOK things because not even water can absorb it. Radio waves are so low in the spectrum that they can only really be detected at all by metal. It's the only thing dense enough to absorb it. Really low RF, even when sent with thousands of watts, requires very large arrays of metal to even detect. It does have the advantage of RANGE though, due to the ease at which it passes through air, and is reflected by the ground (and the upper atmosphere as well, mattering on the RF).

Cell phones are high frequency radio frequency transmitters, technically into the "microwave" band of the spectrum (Barely. You're better off thinking of it as radio frequency to be honest). The choice of this frequency is so the transmitter can be small and low power. It's also why cell phones have fairly short range. You can also block cell phone frequencies with a decent bit of metal or earth. If you've ever been a floor or two underground, you'll know what I mean. They're much lower frequency than your microwave, far lower than visible light let alone some of the more dangerous UV radiation the sun hits us with. Basically, EM's interaction with our body any deeper than the skin stops at roughly UV. By light, you're just generating heat in the skin. Lower than that, it mostly passes right through.

Our skin is actually a superb absorber of EM for something so flexible. We use it as a radiation shield and without that functionality the sun would kill us all. At the top end, our skin is unable to protect us from x-rays (though it does screen quite a bit of those too, btw) and on the bottom end, it doesn't need to protect us.

About the only scientifically discussable threat from low frequency RF is in the particular area of the spectrum too low to be absorbed by our skin but perhaps high enough to be absorbed by our denser bits (particularly organs, perhaps the brain). There has been a lot of studies in this area though, and bottom line is your skin works very well. If it heats up, it's protecting you. If it doesn't, the RF is passing right through you harmlessly.

I've generalized a lot, but I hope this helps.

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Re: Radiation Chart

Postby stevey_frac » Wed Mar 23, 2011 1:38 am UTC

This is nit-picky but:

Microwave radiation is dangerous if it is at levels high enough to cause surface heating. Please note, that it is not dangerous because it will give you cancer, but rather, it is dangerous because you are literally microwaving yourself, and that isn't healthy.

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Re: Radiation Chart

Postby drkslvr » Wed Mar 23, 2011 5:24 am UTC

stevey_frac wrote:This is nit-picky but:

Microwave radiation is dangerous if it is at levels high enough to cause surface heating. Please note, that it is not dangerous because it will give you cancer, but rather, it is dangerous because you are literally microwaving yourself, and that isn't healthy.

It is a little nit-picky, but it could warrant investigation if statistics suggest a phone-cancer link in the future. There is so little we know about the nature of DNA-protein interactions in our cells. Maybe the heat affects methylation, or the repair mechanism for cross-links, or the way chromosomes fold. All of these things are based on proteins, which don't need ionizing radiation to be disrupted. If there ever is a link found between cell phones and cancer, this is where I am placing my bets.
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Re: Radiation Chart

Postby skeptical scientist » Wed Mar 23, 2011 7:42 am UTC

tobbel wrote:I noticed an error in the chart (not Randalls fault as it is wrong on wikipedia also, and I made a note on the talk page for now), but the mammogram dose used in the chart is too high. This is because that it is not given as the effective dose (ie whole body equivalent dose) but rather in the equivalent dose, which unfortunately also uses the sievert-unit. The source is this article http://www.nejm.org/doi/full/10.1056/NEJMra072149 which clearly states “organ doses”. That is, it is the breasts that receive 3 mSv, and the effective dose is instead 3 x 0.05 mSv = 0.15 mSv and this should be the value that is used for comparisons. See http://en.wikipedia.org/wiki/Effective_dose and http://en.wikipedia.org/wiki/Sievert.

Have you pointed this out to Randall? He doesn't read the forums, but I suspect he would find this comment interesting and helpful.
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Re: Radiation Chart

Postby tobbel » Wed Mar 23, 2011 9:10 am UTC

skeptical scientist wrote:Have you pointed this out to Randall? He doesn't read the forums, but I suspect he would find this comment interesting and helpful.


No I havn't, was kinda hoping that he would be reading the forums...

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Re: Radiation Chart

Postby Adacore » Wed Mar 23, 2011 1:40 pm UTC

On the subject of organ doses, which is more important - the peak-dose density or the average/effective dose?

For example, if your breast receives 300 mSv (I've deliberately increased this to get it into the 'clearly linked to cancer' range), is this more likely to cause cancer than an effective full-body dose of 15 mSv? I honestly don't know, and I'm not even sure if there's any evidence either way, but it strikes me as an interesting question. Perhaps quoting '3 mSv' is more appropriate than quoting '0.15 mSv' for the mammogram.

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Re: Radiation damage

Postby engr » Wed Mar 23, 2011 2:45 pm UTC

JoeBloggs wrote:Is radiation damage a linear function of exposure in SV?
eg someone exposed to 4 Sv is twice as screwed as someone exposed to 2 Sv (over the same time interval)

Depends on whom you ask, it's a fairly controversial topic.
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Re: Radiation Chart

Postby skeptical scientist » Thu Mar 24, 2011 1:41 am UTC

tobbel wrote:
skeptical scientist wrote:Have you pointed this out to Randall? He doesn't read the forums, but I suspect he would find this comment interesting and helpful.


No I havn't, was kinda hoping that he would be reading the forums...

He hasn't logged in to the forums since June 2009. You could try commenting on the blag post, sending him an email, or getting his attention on irc.
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Re: Radiation Chart

Postby Dark567 » Thu Mar 24, 2011 2:16 am UTC

Adacore wrote:On the subject of organ doses, which is more important - the peak-dose density or the average/effective dose?

Peak.
http://wormme.com/2010/11/27/doesnt-any ... radiation/

Its generally better to have multiple smaller doses spread out over a few hours, or ideally days, than it is to have a very high dose all at once.
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Re: Radiation Chart

Postby savanik » Thu Mar 24, 2011 10:07 pm UTC

There's a crowd-sourced chart for real-time updates to the nuclear situation in Japan. It's pretty neat, even gives estimates for how much you'd absorb if you lived at the site of the counter for a year at that rate.

According to the chart, the highest, most radioactive source nearby is on the northeast end of Tokyo, and would give you just shy of one red square if you lived there for a year. That's more than the EPA says a member of the public is supposed to get in a year, but less than a nuclear plant engineer's yearly dose limit. And about a tenth of the dose linked to cancer.

There may be individually hotter spots running around, but it's a pretty good look at how much the Japan public should be worried about it - or not.

Edit: And I didn't even read down to the bottom, where they linked to the chart in the article I found it in!
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Re: Radiation Chart

Postby Skispcs » Fri Mar 25, 2011 2:29 am UTC

I know the difference between ionizing and non-ionizing radiation and the differences in the way it impacts the human body.
Something that has always hung out in the back of my head is my friend that received radiation burns from a 1 KW HF radio transmitting at about 10Mhz.
Long story, but he went out by the antenna without following proper procedure, but anyhow.

Were those burns caused by the heating of the cells or something else?

Thank You

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Re: Radiation Chart

Postby tobbel » Fri Mar 25, 2011 10:28 am UTC

skeptical scientist wrote:He hasn't logged in to the forums since June 2009.[/url] You could try commenting on the blag post, sending him an email, or getting his attention on irc.


I've sent him an email now, and also noticed someone else commenting on the radiation chart post... Maybe he'll change it...


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