Mobile phones generate non-ionizing radiofrequency electromagnetic
radiation generally at either 900MHz or
1.8GHz. However, in addition to the RF signal, there are
lower frequency pulsed components associated with Time
Division Multiple Access (TMDA) at 217Hz and 8.34Hz
and a 2Hz Discontinuous Transmission (DTX) component
produced when the user is connected but not speaking [3].
These low frequency components not only pulse the RF
carrier wave, they also generate low frequency magnetic
fields via batter current pulses.
The rapid proliferation of mobile phones has resulted in a
public controversy surrounding possible health effects
connected to their use. Though there are strict guidelines
governing the power output of these devices, there have
been many reports of non-thermal bioeffects from mobile
phone-type exposure [e.g. 4,5]. Experimental evidence has
been presented which supports both sides of the debate
[4,5,6].

Mechanisms based on ferromagnetic transduction via
nanoscale biogenic magnetite have a sound biophysical
basis but have not been thoroughly evaluated experimentally.
Magnetite is a ferrimagnetic iron oxide which can
couple strongly to external electromagnetic fields due to
its permanent magnetic moment. This material was first
discovered in human brain tissue in 1992 and has since
been confirmed to be present as a naturally occurring iron
phase in many regions of the brain with particularly high
concentrations in the meninges (the outermost region of
the brain closest to the mobile phone when in use) [8,9,10].
Transduction of mobile phone signals via biogenic magnetite
can be accomplished in two ways: (i) mechanical
activation/disruption of normal cellular processes due to
low frequency battery current pulses [2]; (ii) local deposition
of energy due to ferromagnetic resonance [1].
In the case of magnetic activation of ion channels, low frequency
magnetic fields generated by battery current pulses
at 2 Hz (DTX) exert a torque on nanoscale magnetite particles
coupled to the cell membrane either directly or indirectly
via cytoskeletal attachment. This torque produces a
mechanical deformation of the membrane which activates
mechanosensitive ion channels.

Magnetic and electron microscopic analyses of human brain tissue have
revealed that biogenic magnetite in human brain tissue is
similar to that produced by the magnetotactic bacterium M.
magnetotacticum [8,9].