Research into this area is inconvenient so it rarely receives much funding. Mobile phone corporations are known to have selectively published their findings and covered up those which supported DNA damage from radiation. There is a history of scientific misconduct in this area going back to the 70's.
Studying the true nature and effects of low-level EMF radiation is a new frontier and progress has been hampered by financial interests. Some corporations like motorola would prefer the public to be oblivious so their profit horizons can continue.
In short, very little is known about EMF radiation (from cell phones and wireless devices) so you should be fairly cautious.
Remember that it is awfully convenient to dismiss this health concern, convenient for your tech usage and hundreds of corporations.
In any case, never forget the world runs on INCENTIVE, not ethics.
Cell Phone radiations deliver strong enough power to carry information back and forth from outer space and put it in your pocket, and after a long enough period of time this could cause major problems. An interesting study would be to test cells in the primary cell using ear compared to the other.
I believe we have some cases of cancer that are significant to this point but we do not have direct proof, only speculation. It is possible that cell phones have enough concentrated radiation to cause detrimental health effects in humans. I am sure the medical sciences will answer this question in the future.
Despite many popular fears about the effects of cell phones on the general population, there has been no credible research to show that there could be detrimental health effects. There is no so called "radiation" that comes from cell phones, and there is no reason that cells in the human body would be effected.
I do not think that cell phones have enough concentrated radiation to cause a big health effect on humans. I think that people are naturally exposed to a certain amount of radiation, and that is basically normal. I only think it could become a problem if they started having way more radiation than normal.