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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. ... 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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In terms of bulk heating, you're correct and the effects are completely harmless. And some cell types are used to natural heating and cooling, and have mechanisms to cope with that. But that's also a very simplistic way of looking at things. Consider for a moment about what's happening at smaller scales, both temporal and physical. That is to say transient heating of minute volumes. That could be sufficient to denature a small collection of molecules, and that could be enough to mess up critical cellular processes if it happens in the wrong place at the wrong time. Low probability, certainly. But could it cause problems, yes, when looked at over a long period. Does this happen in practice? That's a much more difficult question to answer. Is even thinking about such details and asking that sort of question wrong? No.
Nice to see my post marked as a "Troll"; good to see my PhD in cell biology and time spent looking at cell signalling pathways for a pharma company are valued by the slashdot collective. Seriously now, did anything I wrote above contradict the article? No. I merely posed some questions and thoughts regarding the details. Your response was unnecessarily flippant. Are you *absolutely sure* you're correct here, and you've considered every factor? We simply can't be that sure. Science, and biology in particular, isn't about absolutes and certainty of that nature.
There is no such thing as digital, unless you are talking about quantum mechanics. All digital phones, even digital computers, are fundamentally analog systems. Digital means that you ignore all signal level below a threshold. Something like -55dB/decade.
That's true, but it's irrelevant to the discussion, and you're being pedantic. The cellular companies themselves provided the digital / analog nomenclature to differentiate between the two systems. And in the context of the current discussion, the difference is important.
The average transmitted power of handsets on the old analog cellular networks was far higher than that on handsets using a digital network. And I can attest to the difference. The first cell phone I ever used was analog. When I held it to one ear, in a few minutes I would get an uncomfortable itching sensation that felt like it was inside my head, two or three inches above my eye and slightly to the outside. So I'd change ears, and the sensation would go away - only to come back on the other side a few minutes later. This happened every single time I used the phone for more than a couple of minutes.
When I started using a digital handset, the problem mostly went away. I'd still feel that itch occasionally when using the phone though. And every time it happened, when I looked at the display the phone was in analog mode. Since cell networks abandoned analog mode altogether, I've never again felt that sensation in my head.
No, correlation is not causation, and my experience might be unrelated to the handset transmitter power and the signal's characteristics. Nevertheless, when studying whatever biological effects might arise from close-up exposure to RF fields, average transmitter power has to be considered an important variable, just as dosage would be considered in a drug trial.
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