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.
King
R W
RW
Gordon McKay Laboratory, Harvard University, Cambridge, MA 02138-2901, USA. owens@deas.harvard.edu
D000200:Action Potentials; D004574:Electromagnetic Fields / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D009474:Neurons / Q000502:physiology* / Q000528:radiation effects*