In general, all of us MUST keep in mind that the human body is an electrical system. It will be, and is affected by, outside RF energy fields that can promote unwanted nerve stimulation, cancer, heating effects, and many other unwanted effects.
A comparison table for telephone effective radiation head exposure has been developed to provide reference values.  This value varies considerably for dozens of different cell phone models tested. DNA breakdown is among the most disturbing findings of studies done, which can lead to illness and tumors. There are now new links to brain cancer being uncovered as you read this. There is new concern over those that wear cell phones on their belts, because of the close proximity of the antenna to kidneys. The liver which can rebuild itself to some degree after being damaged, but your kidneys cannot.
One notices that RF exposure studies in the media from Europe are much more common and considerably more vocal than those done in America. Publishing negative study results in North America will have a negative effect on the billion dollar market, and subsequently affect stock in cell phone companies. Cell companies have managed to keep the lid nailed shut on the box, in so far as mainstream media are concerned, but this can only last for so long. I personally was not convinced of the damage potential of low level RF radiation for more than 20 years. That is, until reading a number of test results, all saying very much the same thing about observed detrimental effects on living organisms.
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