Cardiovascular response of rats exposed to 60‐Hz electric fields

Abstract

Recently, it has been reported that exposure to high-strength electric fields can influence electrocardiogram (ECG) patterns, heart rates, and blood pressures in various species of animals. Our studies were designed to evaluate these reported effects and to help clarify some of the disagreement present in the literature. Various cardiovascular variables were measured in Sprague-Dawley rats exposed or sham-exposed to 60-Hz electric fields at 80 or 100 kV/m for periods up to four months. No significant differences in heart rates, ECG patterns, blood pressures, or vascular reactivity were observed between exposed and sham-exposed rats after 8 hours, 40 hours, 1 month, or 4 months of exposure. Blood pressure and heart rate measurements, made during exposure to a 100-kV/m electric field for one hour, revealed no significant differences between exposed and sham-exposed groups. In addition, physiologic reserve capacity, measured in rats subjected to low temperature after exposure to 100 kV/m for one month, showed that electric-field exposure had no significant effect on physiological response to cold stress. Our studies cannot be directly compared to the work of other investigators because of differences in animal species and electric-field characteristics. However, our failure to detect any cardiovascular changes may have been the result of 1) eliminating secondary field effects such as shocks, audible noise, corona, and ozone; 2) minimizing steady-state micro-currents between the mouth of the animal and watering devices; and 3) minimizing electric-field-induced vibration of the electrodes and animal cages.

Dose response study of human exposure to 60 Hz electric and magnetic fields

“…When higher electric field strengths were used [see, e.g., Hauf, 1974Hauf, , 1982Stollery, 19861, no reliable effects were found. Similarly, Hilton and Phillips [1980] found that, in rats, exposure to 80-100 kV/m fields produced no changes in heart rate, while exposure to 50 V/m electric fields resulted in decreased heart rate [Fischer et al, 19761. For dogs, Gann [ The cardiac control mechanisms that might be responsible for field-related slowing of heart rate are not known.…”

Chronic exposure to 60‐Hz electric fields: Effects on pineal function in the rat

“…The system used to expose rats to a uniform, vertical 60-Hz electric field has been described by Jaffe et a1 [1980], and by Hilton and Phillips [1980]. Briefly, the rats were exposed in a parallel-plate exposure system, with the rat in electrical contact with the reference ground electrode.…”

Effects of intermittent 60‐Hz high voltage electric fields on metabolism, activity, and temperature in mice

“…The increased frequency of shuttle-box traverses in the first hour of exposure in rats reported by Hjeresen et a1 [1980] is also consistent with the notion of increased arousal at field onset. Surprisingly, Hilton and Phillips [1980] failed to record significant changes in heart rate or blood pressure in rats during an hour-long exposure to a 60-Hz electric field at 100 kV/m. It is possible that the restaint stress necessary to obtain their measures elevated baseline values and masked a field effect.…”