Microwave biological effects: An overview

Although most investigators accept the fact that "high power density" of microwaves can result in pathophysiological manifestations of a thermal nature, some reports have suggested that "low power density" microwave (MW) energy can affect neural and immunologic function in animals and man. Most of these reports have emanated from the USSR and other Eastern European countries. Since most reported "low-level" effects relate to behavioral and central nervous system changes, studies are needed to determine the nature and mechanism(s) of the nervous system's reactions, if any, to electromagnetic fields and to investigate the degree to which the individual's performance capabilities may be affected. Because of their important integrative and regulatory functions, the neuroendocrine and central nervous system should receive attention as possible sensitive areas. Neurochemical assays and immunologic reactivity could indicate basic mechanisms of interaction. A critical review of studies into the biological effects of MW's indicates that many of the investigations suffer from inadequacies of either technical facilities and energy measurement skills or insufficient control of the biological specimens and the criteria for biological change. There is a great need for systematic and quantitative comparative investigations, using well-controlled experiments. This should be done by using sound biomedical and biophysical approaches at the various organizational levels from the whole animal to the subcellular level on an integrated basis, with full recognition of the multiple associated and interdependent variables. Above all there is a need for scientific competence and integrity. It is important to maintain a proper perspective and assess realistically the biomedical effects of microwave exposure, so that the worker or general public will not be unduly exposed nor will research, development and benficial utilization of this energy be hampered or unecessarily restricted.