No, you are quite right; the “bluetooth” which is attached to your head, works by magic and good will, not UHF radio waves between 2.4 and 2.485 GHz. In addition it is far better to have those radio wave concentrated on your head, rather than your leg; Due to the way your thigh is the protective container for the main organ in your central nervous system, whereas your skull is simply a concentration of muscle and bone used in locomotion.
Once again, there has been no statistically significant link between use of a mobile phone and, for example, cancer. See the following papers for further information (I’ve included a statement on the results from the abstract of each);
Epidemiology of health effects of radiofrequency exposure, A Ahlbom et al, Radiat Res. 2006 May;165(5):608-15.
Effects of cell phone radiofrequency signal exposure on brain glucose metabolism. ND Volkow et al, JAMA. 2011 Feb 23;305(8):808-13. doi: 10.1001/jama.2011.186.
Mobile phone base station radiation does not affect neoplastic transformation in BALB/3T3 cells. H Hirose et al, Bioelectromagnetics. 2008 Jan;29(1):55-64.
The effects of pulsed 860 MHz radiofrequency radiation on the promotion of neurogenic tumors in rats.
BC Zook & SJ Simmens, Radiat Res. 2006 May;165(5):608-15.
I can understand that you want to believe that something like this might be the case, however please do understand that there is an overwhelming body of evidence against this theory and in effect you are giving in to superstition about the mysterious magical rays that power the modern world.