We know that radiation from cell phones is too weak to heat biological tissue or to break chemical bonds in cells. But the radio waves they emit can effect cell behavior. Studies done at the Finnish Radiation and Nuclear Safety Authority in Helsinki found that two proteins were altered in skin cells. After stimulating an hour-long phone call they found one protein increased by 89%, the other decreased by 32%. The researchers are not ready to conclude that these changes translate into a negative health effect. But it does mean that the human body recognizes this low-level radiation and reacts to it. Terry Pfau DO ,HMD