TISSUE INJURY FROM EXPOSURE TO POWER FREQUENCY ELECTRICAL FIELDS Raphael C. Lee The University of Chicago Burn/Electrical Trauma Center Section of Plastic & Reconstructive Surgery Department of Surgery and Department of Organismal Biology & Anatomy The University of Chicago Chicago, IL 60637 INTRODUCTION The biological effects of electric fields is a topic that is gaining increasing attention. The spectrum of effects recognized in both the scientific and medical literature range from the subtle, such as altered gene expression, to the dramatic such as tissue destruction. In general, these effects are frequency-dependent. Ionizing fields with frequencies greater than 10 21 Hz cause cellular damage by physicochemical processes very different from the damage resulting from power-frequency (50-60 Hz) electrical shock. Significant progress is being made in understanding these processes. The intent of this review is to focus on the problem of power- frequency electrical injury. Recent developments in understanding this important problem have led to the possibility of exciting new medical therapies. Historically, power-frequency electrical shock became a significant public health problem prior to the tum of the last century. The rise in the incidence of electrical shock corresponded with the development of the electric lamp and the explosive growth of the use of electrical power, which occurred between 1880 and 1900. It became clear that power- frequency electrical force was capable of very destructive effects on living systems [lex-Blake, 1913]. Soon thereafter the electric chair was developed and the first legal electrocution occurred in the State of New York in Auburn Prison in 1890 [Bernstein, 1992]. The optimized design of these devices and the many studies on electropathology which were carried out are still the source of much useful information regarding the effects of electricity on the body. Today, most serious electrical trauma occurs in the work place of the industrialized nations. The mortality rate for accidental electrical shock ranges from 3 to 15%, with about 1,000 deaths attributed to electrical shock in the United States annually. More than 90% of the injuries occur in males, mostly between the ages of 20 and 34, with 4 to 8 years experience on the job. Deviation from standard safety guidelines is the most common cause LGourbiere, 1992]. Advances in Electromagnetic Fields in Living Systems, Vol. 1 Edited by J.C. Lin, Plenum Press, New York, 1994 81