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Cellphones Do Not Cause Brain Cancer, Says 29-Year Study (gizmodo.com)
A study from Australia reassures us that cellphones are reasonably safe, and do not cause brain cancer. Chris Mills writes from Gizmodo: "The study examines the incidence of brain cancer in the Australian population between 1982 to 2013. The study pitted the prevalence of mobile phones among the population -- starting at 0 percent -- against brain cancer rates, using data from national cancer registration data. The results showed a very slight increase in brain cancer rates among males, but a stable level among females. There were significant increases in over -70s, but began in 1982, before cellphones were even a thing." What makes the study in Australia so authentic compared to other studies conducted in other countries is the fact that all diagnosed cases of cancer have to be registered by law.
Photons from microwaves can't ionize matter. This is why ultraviolet photons are so dangerous: they can cause chemical changes in living tissue. Microwaves can't do that it it is silly to worry about it.
http://michaelsmith.id.au
Neither TFA nor the researchers make the claim that "cell phones don't cause cancer". That was made up by whoever wrote the Slashdot summary.
O RLY? I disagree. I believe TFA really does say that cellphones don't cause cancer. They provide a bunch of supporting arguments and evidence of such, and then conclude with "We have had mobiles in Australia since 1987. Some 90% of the population use them today and many of these have used them for a lot longer than 20 years. But we are seeing no rise in the incidence of brain cancer against the background rate." What message do you think they want us to take away?
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Cellphones output less power and lower frequency than IR at room temperature. Human body temperature emits more than 400watts per square meter of skin in blackbody radiation. The only danger cellphones create is localized heating because they're not in thermal equilibrium, but the total energy is much lower.
Personally, I'm more worried about the localized heating caused by taking a hot shower. That is much more EM radiation than my cell phone and more deadly type of radiation, and it dries out my skin. A hot tub is right-out, along with exercising, and almost anything else that warms up your body more than a cell phone. The only thing more deadly is a lightbulb, of any kind. Very high frequency EM radiation compared to microwave, and much higher amounts of total radiation. Even possibly localized heating if you sit near an incandescent bulb.
Photons from microwaves can't ionize matter. ... it it is silly to worry about it.
There are other ways to foul DNA than ionization. For starters, it is a long molecule with charged regions. One way that you can detect electrocution is that the DNA in the cells has uncoiled and lined up in parallel along where the electric field was oriented. Since the folding and unfolding of DNA is part of the regulation of gene expression that could have non trivial effects. (On the other hand, that's an effect observed when the exposure to electrical activity is extreme, so any effect might be lost due to the death of the affected cells.)
BUT....
A very substantial effect of electrical (and changing magnetic) fields on cells HAS been detected. It is being used therapeutically - on brain cancer - with great success.
You may have noticed that the electrical activity in living cells is almost entirely confined to electrical potentials across membranes and fine-grained patterns of charge on molecules that affect their interactions at close range. There is very little involvement with, or sensitivity to, large-scale fields.
On the other hand, you may ALSO have noticed, in pictures or drawings of cell reproduction, that the mechanism for separating the DNA into two nuclei looks very much like field lines, or the patterns iron filings take up in the presence of a strong magnetic field.
This is apparently because the cells use gross electric fields as part of the mechanism for gene segregation. So any other use of large-scale electrical fields has a strong selection pressure against it - it must both avoid fouling cell reproduction and provide an extreme advantage to offset any problems it does cause. Very few mechanisms have made this cut. Similarly, any other sensitivity to large scale electrical fields must be small, to avoid being fouled in turn by the fields that occur during cell division.
So cells are very insensitive to large-scale electrical fields through them, EXCEPT during cell division. But it turns out that fields - especially those from changing magnetic fields, DO interfere with cell division:
- Sometimes they prevent gene segregation. After a while the cell passes the phase where it would divide, but without dividing - resulting in a diploid cell, which then commits suicide via the apoptosis mechanism.
- Sometimes they result in incorrect segregation, resulting in two progeny cells with the wrong compliment of chromosomes. Then both either die through missing genes or again commit suicide.
Brain nerve cells, along with most of the cells supporting them, are very long lived and rarely reproduce - to the point that for decades it was though that they didn't reproduce at all once the brain was mature. (In fact there is some new nerve growth, which may be involved in learning and mental plasticity. But it is very slow and mostly newly differentiated cells from stem cell lines rather than reproduction of existing nerves.) So the cells of the brain are almost never in the stage where electrical and changing magnetic fields would be an issue.
Cancer cells, on the other hand, reproduce a lot, and spend much of their time in the vulnerable state. So electrical fields that would cause them to die are particularly useful in treating brain cancer, selectively killing the cancer cells while almost never affecting the normal cells with which they are comingled. Electromagnetic coil devices to produce them have recently shown such excellent results in treating inoperable and rapidly fatal brain cancers that the FDA aborted the tests and fast-tracked an approval.
Yes, the individual photons of radio signals are too low energy to ionize most molecules. But they are coherent and their fields add up to enough to have major electromechanical effects. (They COULD also add to produce ionization, especially on structures appropriately sized or massed-and-sprung to resonate, but at the levels involved in a cellphone this
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Yup, autism causes vaccines (and probably better cell phones too).
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Digital means that you ignore all signal level below a threshold. Something like -55dB/decade.
This is how computers measure digital signals but it is not how digital RF systems work. You are right in that digital RF is fundamentally analogue but they do so by measuring differences in a continuously transmitter carrier signal at a specific frequency.
In the early days of mobile phones they were incredibly simple. They used frequency modulation of the carrier where the frequency change from the true carrier was related to the analogue signal on that carrier. Dead simple to decode.
These days RF signals still have the same carrier and they still operate the same fundamental way by altering the phase, frequency or amplitude of the carrier in relation to what is being sent across. The only difference is now this change in carrier is related to zeros and ones rather an analogue audio waveform.
All of this ignores the fact that even early analogue cellphones had a "digital" component which was used to communicate with the base stations. How else would the provider know to which base station to route the phone conversation, and how else would the individual phone itself know the call was for it, and not someone else.