This study examined the possible ability of  2.45 GHz microwave radiation exposure (30 min) to modify the expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Ninety minutes after radiation, HSP-90 and HSP-70 had decreased significantly (P<0.01); Twenty-four hours after radiation, HSP-90 had partially recovered and HSP-70 had recovered completely. There were few indications of lesions in the glandular structure and signs of apoptosis were negative in all radiated animals. The results suggest that acute sub-thermal radiation at 2.45 GHz may alter levels of cellular stress in rat thyroid gland without initially altering their anti-apoptotic capacity.
Want an official word on the matter? The World Health Organization, which tends to err on the side of caution before outright dismissing something as toxic, carcinogenic, or otherwise harmful, is very clear that there is no health risk from radio-frequency communication devices. (Their briefing on the matter is actually a great read that highlights how low the risk is and how even people in Wi-Fi dense locations like schools and hospitals are exposed to radio-frequency radiation at thousands of times lower than international safety standards designed to protect individuals working in related industries).
We really do not recommend any kind of chip, guard, anti-radiation "filters" or incomplete shielding case because honestly, how could they NOT provide a false sense of security? Folks could believe these products make them “invincible” against radiation so they are comfortable holding the case right up to their heads-and the radiation seeping from the back and the side of the phone case is in very close proximity to their precious brains. Oh no!
Bluetooth allows your phone to communicate with other devices, such as the hands-free option in your car or your printer. If accessed by someone else though, they could misuse it to access your information or intercept your calls. Turn off the Bluetooth on your phone and turn it on only when you need to connect with other device. Many phones also allow users to set passcodes or additional security levels on their Bluetooth as well. Use all available options to increase your privacy.
Cancer is the obvious start. An early concern with mobile technology was clusters of the disease around those living near phone masts. One study in Israel found a 4.5-fold increase in cancers of all kinds in the immediate vicinity of a mast (Int. J. Cancer Prev., 2004). In 2009, a Korean team of researchers carried out a pool analysis of the results of 23 studies, which involved almost 38,000 subjects.