Electromagnetic and Thermal Simulations of Human Neurons for SAR Applications

Abstract

The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by HN for medical diagnosis and treatment. Research issues including the wave frequency, power intensity, reflections and scattering, and penetration depths are of important considerations to be incorporated into the research study. In this study, computer simulation for the EM exposure to HN was studied for the purpose of determining the upper limits of the electric and magnetic field intensities, power consumption, reflections and transmissions, and the change in temperature resulting from the power absorption by human neurons. Both high frequency structural simulators (HFSS) from ANSYS software, and COMSOL multi-physics were used for the simulation of the EM transmissions and reflections, and the temperature profile within the cells, respectively. For the temperature profile estimation, the study considers an electrical source of 0.5 watt input power, 64 MHz. The EM simulation was looking into the uniformity of the fields within the sample cells. The size of the waveguide was set to be appropriate for a small animal model to be conducted in the future. The incident power was fully transmitted throughout the waveguide, and less than 1% reflections were observed from the simulation. The minimum reflected power near the sample under investigation was found to be with negligible reflected field strengths. The temperature profile resulting from the COMSOL simulation was found to be near 0.25 m°K, indicating no change in temperature on the neuro cells under the EM exposure. The paper details the simulation results for the EM response determined by HFSS, and temperature profile simulated by COMSOL.

Repeated electromagnetic field stimulation lowers amyloid-β peptide levels in primary human mixed brain tissue cultures

“…REMFS may not depolarize neurons. It radiates low energy coupled electromagnetic fields with non-thermal effects at a frequency of 64 MHz that activate intracellular biomolecules; it allows to stimulate the brain areas located up to 13.49 cm from its surface 73 . Secondly, TMS treatment significantly decreased levels of APP in AD mice treated with TMS: 67.1 ± 10.0% relative to non-treated mice, p < 0.05 101 .…”

“…Many different types of cells that respond to EMF exposures 71 , 72 , the present study adds primary human neurons and glia to the growing list, and attempts to establish the lowest SAR capable of producing potentially specific, non-thermal effects. As discussed in our mathematical model and computer simulation articles, we calculated the applied SAR to our cell cultures 34 , 73 , a 64 MHz frequency allowed us to minimize power needed to obtain the minimum SAR with biological effect, often called “MSBE”, permitting the use of an average SAR that was well below the permitted values of 2 W/kg (Watts per kilogram) set forth by the International Electrotechnical Commission (IEC). Thus, our conditions provide an established framework for safe human exposure (Table 1 ).…”

Mother’s Exposure to Electromagnetic Fields before and during Pregnancy is Associated with Risk of Speech Problems in Offspring

“…The effect of electromagnetic fields on human neurons has been studied for decades [21]. While some studies could not show any neurobiological adverse effects in healthy and vulnerable RF EMF-exposed animals [22], other studies confirm the role of these exposures on neurodevelopment.…”

The Effect of Repeated Electromagnetic Fields Stimulation in Biological Systems

“…that will produce uniform internal fields similar to our previous studies when applied to a human brain with a target SAR of 0.4-0.9 W/kg [40]. Initially, we determined by mathematical and computer modeling that the REMFS exposures in our biological studies delivered a safe thermal and SAR measurements [70]. With these results we developed a virtual exposure system by numerical model and computer simulation.…”

“…Using similarities in dosimetry between cell cultures, animal exposure, human phantom exposure, and computer simulation it is possible to adjust conditions for human exposure [70]. Thus, we used frequencies more suitable for human exposures .…”