Trends in nonionizing electomagnetic radiation bioeffects research and related occupational health aspects.

The international literature (circa 1970-1977) on biological and clinical phenomena associated with exposure to microwave or radiofrequency (RF) electromagnetic (EM) fields was selectively reviewed. It was concluded that the mechanisms by which EM fields exert their biological effects are becoming better understood as investigative technology and methodology improve. Concurrent with this trend, there is some recent eivdence in the West which supports traditional Soviet and some European claims that EM fields can affect nervous system function and morphology in small mammals, birds and invertebrates at power levels below those defined as thermogenic in the West. These experimental findings coupled with the pressure of public opition may eventually have a significant effect on the establishment of revised occupational exposure limits and on unique positions regarding maximum permissible exposure (MPE). At present, the exposure level established in the Soviet Union is 0.01 m W/cm2 for a work day, while the United States adheres to a level of 10 m W/cm2 averaged over 0.1 h. At the same time, however, findings from clinical studies conducted in the West do not corroborate findings from extensive clinical surveys of occupational workers collected in Russia and in some East European countries. The latter continue to report a plethora of psychophysiological dysfunctions and impairments of a reversible nature as a result of chronic exposure to EM fields of relatively low power density (e.g., less than 10 m W/cm2, and occasionally below the 1 m W/cm2 level). Neither is there any recent compelling evidence to support certain speculations that modulated EM fields can be used to remotely control human behavior. Interaction between the concerned research and development communities in the East and West has increased substantially in the 1970s. Such interaction promises to provide a medium in which differences in doctrine, experimental methodology and protocol, and the interpretation of biological and clinical phenomena may be resolved.