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Possible Cellphone Link To Cancer Found In Rat Study (nbcnews.com)
An anonymous reader quotes a report from NBC News: A giant U.S. study meant to help decide whether cellphones cause cancer is coming back with confusing results. A report on the study, conducted in rats and mice, is not finished yet. But advocates pushing for more research got wind of the partial findings and the U.S. National Toxicology Program has released them early. They suggest that male rats exposed to constant, heavy doses of certain types of cellphone radiation develop brain and heart tumors. But female rats didn't, and even the rats that developed tumors lived longer than rats not exposed to the radiation. The National Toxicology Program, part of the National Institutes of Health, is still analyzing the findings. But John Bucher, associate director of the program, said the initial findings were so significant that the agency decided to release them. A 29-year-old study published earlier this month from Australia reassures us that cellphones are reasonably safe, and do not cause cancer.
This ihas been on Facebook all day and driving me up a wall. Take a look at the actual report, something no journalists seem willing or able to do. From the report:
"Exposures to RFR were initiated in utero beginning with the exposure of pregnant dams..."
"All RF exposures were conducted over a period of approximately 18 hours using a continuous cycle of 10 minutes on (exposed) and 10 minutes off (not exposed), for a total daily exposure time of approximately 9 hours a day, 7 days/week."
So yes, if you have been using a cell phone since before you were born, and using it for NINE HOURS A DAY, you have cause to be worried.
Otherwise, take a deep breath, read the Australian study that said there have been no increases in brain cancer over the past 29 years, and give me a call. I'll be on my cell phone.
The study design is worse than that.
Firstly - it adjusts the power so that the wattage per gram is over the whole body.
As a comparison - to do the same with a human with a phone and 6W/kg, would need a 600W or so transmitter (average). (mobile phones typically peak at 2).
It would be so much power it would make you about as warm as sunlight falling on your skin.
In humans, there are several major differences in real life, and in the standard used. ... 'were observed in the head and neck and other sites throughout the body'.
Firstly, it is the peak absorbtion of the gram or ten (US or EU) that is absorbing most signal. This means that even neglecting hours a day of usage, small movements around the head, or using it in a different ear will dramatically reduce the time at peak SAR.
Secondly 'develop heart tumors' - if you look at page 12 of the study, a real problem emerges.
They say 'therefore organs other than the heart were examined for tumors'
But.
Then they present a table, specifically breaking out 'heart' - which shows an apparent effect, from 'others' which really don't.
They do not - for example - show line entries in the tables for 'head' 'neck'.
This is a problem because if you take 20 sites throughout the body, and then analyse them against the control, even with no effect, you will often get an apparently statistically significant result.
This would be less concerning if the numbers were larger - however one more or less rat in the control group getting cancer of the heart (or other parts) would skew this to significant or insignificance.
Secondly, their control rats did not live as long as they historically should have, compared to other studies.
Because it is non-ionizing radiation, incapable of breaking molecular bonds (literally incapable, incapable at a quantum level) AND the total power of the radiation makes it about as dangerous as a flashlight as far as integrated power is concerned. You are at greater risk every time you go out into the sunlight, which is full of ionizing radiation. You are even at greater risk in fluorescent light, which is converted visible light from a UV base and usually with a comparatively high UV component (which is potentially ionizing).
The problem (one of many) with epidemiological studies like this is that correlation is not causality. Yes, I know, so very true and well known that it sounds like a trite little aphorism rather than something to be taken seriously but all the study could be reflecting is that males with cell phones are more likely to fly in airplanes than females with cell phones, and airplanes take you up well above the protective layers of the atmosphere where you get a dose of real ionizing radiation. Or males with cell phones are more likely to work in poorly ventilated buildings made with concrete and hence breathe in more radiation (again, ionizing). Or there may be a covariance with something in their differential diets. Or it could be something two or three fold indirect.
Bottom line, until somebody can suggest a physically plausible mechanism for non-ionizing radiation in power densities far lower than that already present in living tissue to cause cancer, one should pretty much ignore any studies that find borderline "significant" correlation, especially when it isn't consistent (males but not females), especially when there are many other studies that find no significant correlation. I would wax poetic about data dredging, green jelly beans causing acne (obligatory XKCD reference), and Bonferroni corrections to computations of significance in precisely studies of this sort that find something where others have looked many times and found nothing, but why bother?
In the meantime, let's return to the regularly scheduled program linking high voltage power lines to leukemia and holy water to cancer cures...
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Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.