In 2016 a study reported observing a concentration of magnetite nanocrystals in human brains, with four orders of magnitude larger than previously thought. In the context of magnetite's role and function inside the human brain not being properly understood, this development prompts a question concerning the impact that a significant magnetic near-field component, in the hundreds of MHz range, might have on power loss in tissues having ferrimagnetic properties. This article highlights the importance of thorough research on possible thermal and non-thermal effects that could be caused by the magnetic field component to which one could be exposed while using certain communication devices near or in front of the head. Furthermore, this article provides preliminary estimations of magnetic contribution to the specific absorption rate (SAR) of energy deposition in tissues, using two approaches - one based on existing research concerning magnetic hyperthermia, and the other one based on a simulation model that takes into account the magnetic properties of tissues. By simulating the propagation of a 440 MHz wave in a ``magnetic'' (as opposed to pure dielectric) brain, we observed changes of the SAR values, and, more importantly, superficial hot spots appeared at the surface of small magnetite particles, distributed in the homogenous brain.
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