I'm doing a study that involves radio waves passing through organic matter and have come across several sources that state that radio waves may heat organic matter when passing through it (For example: http://www.mobilfunkstudien.org/downloads/peleg_wm_10.5923.j.biophysics.20120201.01.pdf). However, I am unclear as to the exact physical process that is causing heating. Clearly it isn't scattering since the wavelengths associated with radio waves are nowhere near the order of the diameter of organic cells. Perhaps absorption and the re-emittance? I find this unlikely too. Is it that the fields of the wave can induce a current which heats by resistive heating? Any help would be much appreciated.