Author_Institution :
Dept. of Electr. Eng., Washington Univ., St. Louis, MO, USA
Abstract :
An enquiring skeptic who studies the history of bioelectromagnetics may well come to the conclusion that, associated with any particular region of the spectrum, there is a recurring cycle of “discovery”. It goes something like this. First exploratory work indicates there seems to be an interesting biological “effect associated with low level” exposure to that portion of the spectrum. This precise wording of the phrase in inverted commas is itself important and requires explanation. The term “effect” rather than the term “hazard” is used because it is broader and because an “effect” must be presumed neutral until proven otherwise, besides, while one fears to find a hazardous effect, one could conceivably find a beneficial one. Further, the term “associated with” is used rather than the term “caused by” since the proof of causation is rather more difficult to achieve than the observation of association. Finally, the modifier “low level” is of extreme importance: sufficiently strong ELF magnetic fields can, in principle, induce life threatening eddy currents in a torso; and microwaves can be used for cooking; but the public worry arises over the possibility of hazards which are neither overtly electrophysiological nor overtly thermal. Second, this observation of an interesting bioeffect associated with low level exposure excites comment; and the field seems poised for a breakthrough. Third, other workers eagerly endeavor to verify, extend, or explain the original report. Fourth (occasionally), the effect is confirmed and, its bases having been elucidated, is adjudged not all that startling or worrisome after all. Too often, the effect is not confirmed, and interest in it gradually wanes
Keywords :
biological effects of radiation; health hazards; reviews; ELF magnetic fields; beneficial effect; bioelectromagnetic effects; discovery cycle; electrophysiological effects; hazard; interesting biological effect; life threatening eddy currents; low level exposure; microwave cooking; public worry; thermal effects; torso;