CHANGES IN THE ELECTROCARDIOGRAMS OF RATS AND DOGS EXPOSED TO DC MAGNETIC FIELDS
C.T. Gaffey, T.S. Tenforde · 1979
Early research showed magnetic fields can measurably affect heart function in animals across different field strengths.
Plain English Summary
Researchers exposed rats and dogs to static magnetic fields ranging from 0.5 to 22,000 gauss while monitoring their heart activity through electrocardiograms. The study examined how different magnetic field strengths and animal positioning affected cardiovascular function. This early research helped establish methods for studying magnetic field effects on the heart.
Why This Matters
This 1979 study represents foundational research into how magnetic fields affect cardiovascular function in mammals. While the abstract doesn't detail specific findings, the research methodology is significant because it established protocols for studying magnetic field effects on heart rhythm and function across a wide range of field strengths. The study's approach of testing different animal orientations within the magnetic field suggests researchers suspected that field direction matters for biological effects.
What makes this particularly relevant today is that we're surrounded by much weaker but more complex electromagnetic fields from our devices and infrastructure. While this study focused on static DC magnetic fields up to 22,000 gauss (far stronger than typical environmental exposure), it laid groundwork for understanding how electromagnetic fields can influence one of our most critical biological systems. The cardiovascular effects of EMF exposure remain an active area of research, with modern studies examining everything from heart rate variability to blood pressure changes from wireless device use.
Finding
The major change in the ECG pattern induced by a MF is an increase in the amplitude of the T wave of rats and dogs. This is a confirmation of the observation first made by Beisher and Knepton (Aerospace Medicine 35: 939-944, 1964) on squirrel monkeys in which a 70,000 gauss field caused about an 80 percent rise in the T wave. In our rat study a 20,000 gauss field increased the T wave by about 450 percent; the dog's T wave was increased 750 percent by a 16,000 gauss field.
In their words
“The major change in the ECG pattern induced by a MF is an increase in the amplitude of the T wave of rats and dogs. This is a confirmation of the observation first made by Beisher and Knepton (Aerospace Medicine 35: 939-944, 1964) on squirrel monkeys in which a 70,000 gauss field caused about an 80 percent rise in the T wave. In our rat study a 20,000 gauss field increased the T wave by about 450 percent; the dog's T wave was increased 750 percent by a 16,000 gauss field.”
Figures from the Original Paper
Diagrams extracted from the original research document.
Exposure Information
Specific exposure levels were not quantified in this study.
Show BibTeX
@article{changes_in_the_electrocardiograms_of_rats_and_dogs_exposed_to_dc_magnetic_fields_g5104,
author = {C.T. Gaffey and T.S. Tenforde},
title = {CHANGES IN THE ELECTROCARDIOGRAMS OF RATS AND DOGS EXPOSED TO DC MAGNETIC FIELDS},
year = {1979},
}