NATUR WISSENSCHAFTEN OO Mechanisms of Electromagnetic Interaction with Cellular Systems* W. Grundler GSF-Forschungszentrum far Umwelt und Gesundheit, W-8042 Neuherberg F. Kaiser Institut ft~r Angewandte Physik, Technische Hochschule, W-6100 Darmstadt F. Keilmann Max-Planck-Institut fiir FestkOrperforschung, W-7000 Stuttgart, FRG J. Walleczek Research Service, Jerry L. Pettis Memorial Veterans Hospital, Loma Linda, CA 92357, USA The question of how electromagnetic fields - static or low to high frequency - interact with biological sys- tems is of great interest. The current discussion among biologists, chemists, and physicists emphasizes aspects of experimental verification and of defining micro- scopic and macroscopic mechanisms. Both aspects are reviewed here. We emphasize that in certain situations nonthermal interactions of electromagnetic fields occur with cellular systems. * From a workshop "Wechselwirkungsmechanismen elektro- magnetischer Felder mit zellul~ren Systemen" sponsored by the Deutsche Fo~schungsgemeinschaft (DFG) at the Max- Planck-Institut fur Festk6rperforschung in Stuttgart, Sept. 11 - 12, 1991 D uring the past decade, the study of interactions ~of nonionizing electromagnetic waves with whole organisms, but specifically with well- characterized cellular model systems in vitro, has re- ceived increased recognition: A growing number of ex- perimental findings has been reported each year (for review, see [1 - 7]), and hypothetic mechanisms which might be involved in mediating these effects have emerged [2-8]. Furthermore, the public interest has grown for investigating possible health effects from electromagnetic fields (EMFs) generated, for exam- ple, by 50/60-Hz high-voltage transmission lines, vi- deo display terminals, or clinical NMR-imaging proce- dures. Particular concern came from epidemiological findings which correlate the exposure of humans to weak magnetic fields in the home with an elevated risk for developing certain leukemias and other cancers [9-12]. These results may suggest that nonionizing EMFs have an as yet unrecognized potential for modi- fying human physiology, but they cannot prove a cau- sal relationship. We believe that not epidemiological surveys will decide the basic questions, but rather care- ful cellular studies together with efforts to understand the fundamental mechanisms of electromagnetic inter- action with living systems. The purpose of this article is therefore to give an over- view of selected and recent experimental results, and also survey new theoretical attempts to explain non- thermal actions of EMFs on cellular systems. The Experimental Evidence Laboratory experiments to investigate the biological effects of relatively weak EMFs have been performed for some decades. But only in recent years have the ex- periments reached a level of sophistication which al- lowed a convincing demonstration of some nonthermal field phenomena at the cell, tissue, and whole orga- Naturwissenschaften 79, 551 - 559 (1992) © Springer-Verlag 1992 551