A review of studies on the electric field and the current induced in a human body exposed to electromagnetic fields

Abstract

How high an electric field or current is induced inside a human body when exposed to an electromagnetic field has recently attracted much attention. The background for this is twofold; concern about the possible health effects of electromagnetic fields (usually called 'EMF issues'), and their positive application to medical treatment or new research subjects. This paper reviews various aspects related to this topic in terms of the following items: basic formulas for field calculation, effect of electromagnetic fields, calculation methods, an Investigation Committee in the IEEJ, and future research subjects. 

Power Loss Analysis of a TET System for High Power Implantable Devices

“…7, it illustrates a typical turn-on switching waveform of v c (t) and i c (t) and the waveform can be modeled by the piecewise function (16) and (17). The turn-on switching loss can be calculated by substituting (16) and (17) into equation (5). …”

“…When a TET system is used to supply substantial amount of power (eg, 10 ~ 35W) to an implantable biomedical device, and portability is an essential requirement for the device, then efficiency becomes a very important issue for the application [4]. Poor power efficiency of the system not only shortens the longevity of batteries, but also could cause severe heating effect and health concerns because the secondary circuit of a TET system is implanted inside a human body [5]. Researchers are interested in reducing the size and hence increasing the portability of the external circuit of implantable biomedical devices.…”

New Issues on Electromagnetic Biocompatibility

“…In some epidemiological studies, values of the magnetic flux densities as low as 0.2µT, are mentioned to correlate with significant increase in cancer incidence among populations living nearby power lines [5].…”

A review of studies of the biological effects of electromagnetic fields in the intermediate frequency range

“…When considering the interaction between ELF electromagnetic fields and biological organisms, the electrically induced electric fields and currents inside the organism are a key point. Along with many analyses of induced currents for the ELF range [7], there have already been several reports of calculation of induced current inside an anatomically correct human model for IF magnetic field exposure. These calculations have been conducted on the basis of measured magnetic field distribution [8] or estimated magnetic dipole(s) [9,10].…”