Fields and currents in the organs of the human body when exposed to power lines and VLF transmitters

Thermal noise limit on the sensitivity of cellular membranes to power frequency electric and magnetic fields

Several authors have concluded that thermal electromagnetic noise will be of sufficient magnitude to overwhelm electric and/or magnetic fields induced by environmentally generated, power frequency electric and magnetic fields in the membranes of living cells located in the bodies of humans. Yet, there are research reports that indicate that living cells may respond to power frequency electric and/or magnetic field levels well below the limits set by these thermal noise arguments. The purpose of this study is to suggest that published thermal arguments may not make a full accounting of all membrane force fields of thermal origin, and that when such an accounting is made, the net thermal noise fields may be smaller in the power frequency range than previously thought. If this analysis is correct, there may be no thermal noise barrier that precludes the possibility of cellular membranes of human cells responding to environmental levels of power frequency electric or magnetic fields.

Nerves in a human body exposed to low-frequency electromagnetic fields

Following a summarizing introduction in which the background research is reviewed and referenced, a detailed description is given of the properties of the elongated cell that constitutes a nerve axon. The functioning of the cell membrane is reviewed with reference to the transmission of a frequency-modulated signal. The need for successive regeneration by means of action potentials is described. Propagation within both myelinated and unmyelinated membranes is discussed. Currents and electric fields induced in the organs of the human body by external electric and magnetic fields are introduced and their determination reviewed. The interaction between these currents and electric fields and those involved in the propagation of a signal along a nerve axon is analyzed. It is shown that incident 60-Hz electric fields near high-voltage transmission lines do not induce large enough currents and fields in a nerve axon in the leg to disrupt a propagating signal. Scaling with respect to frequency and size is discussed. Surface sensations due to exposure to electric fields in the 5-15-kV/m range are analyzed. It is concluded that exposure to the electromagnetic field of a 60-Hz high-voltage transmission line or a 10-30-kHz high-power transmitting antenna should have no observable effect on the normal functioning of nerves.

The electric field induced in the human body when exposed to electromagnetic fields at 1-30 MHz on shipboard

The electric field induced in the body of a man standing on the metal deck of a ship near a vertical antenna is determined analytically. Typical antennas for radio communication in the 1-30 MHz band are described and their near fields are calculated. The current induced in the man is determined by solving the relevant integral equation. Explicit formulas are obtained for the total axial current and the associated current densities and electric fields.

An examination of underlying physical principles. The interaction of power-line electromagnetic fields with the human body

A detailed examination of the scientific foundations contained in a number of recent articles has revealed some serious errors. The careful application of advanced mathematical-physical methods to study the penetration of externally applied electric fields into the organs and cells of the human body has obtained new and significant results [8, 9, 32]. Specifically, Eqs. (11) and (12) establish a definite relationship between an incident low-frequency electric field and the current, current density, and electric field induced in the body when the arms are in contact with it and the incident field is parallel to its length. Corresponding formulas with the arms raised are available [10] as are formulas for the current density and electric field in the organs of the body [9]. It is these currents and electric fields that must be used by biomedical research workers to determine their effect on living cells. The proposed interpretation of epidemiological data [31] indicates a risk of leukemia in children when the incident 50-60-Hz electric field generated by a high-voltage transmission line is Einc > or = 61 V/m. (23). The corresponding maximum electric field at approximately 10 m from a 440-kV transmission line is Einc approximately 2100 V/m [8, 9]. The electric fields induced in the different organs of the body by these electric fields are in the range 25.2 < or = E1z < or = 119 microV/m for Einc2z = 61 V/m and 0.87 < or = E1z < or = 4.1 mV/m for Einc2z = 2100 V/m [9]. These are in the range of applied fields in in vitro experiments, which showed significant effects on cells [4], and should serve as guidelines for such experiments.