Are membrane microwave effects related to a critical phase transition?

Abstract

We present a model that can explain reported nonthermal effects in biological membranes that occur when they are exposed to very low intensity electromagnetic fields in the microwave portion of the spectrum. One argument is that the external field drives the membrane closer to a critical point, and that critical fluctuations begin to dominate the behavior of the system. In an alternative argument, the membrane is initially close enough to its critical point for the system to be highly susceptible to specific external perturbations. Thus continuous, i.e., critical, phase transitions serve to mediate the field–membrane coupling via the greatly enhanced susceptibility of the system when it is near its critical point. We also discuss a specific example related to the experimentally observed anomaly in passive sodium ion permeability at the phase transition in the erythrocyte membrane when exposed to microwaves, and we propose additional experiments that will serve to test our hypotheses.