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So far, little attention has been paid to whether EMF exposure might affect the heart. Last year, however, Sastre and his coworkers at the Midwest Research Institute in Kansas City, Missouri, published experimental data showing that 8 hour exposures to intermittent, 60 Hz fields altered heart beat variability in healthy men [ref. 44].
Everyone’s heart rate changes slightly from beat to beat, reflecting fine tuning by the nervous system in response to respiration and other factors. Yet, the magnitude of variance can differ dramatically between individuals. Even when two people each have a heart rate averaging 60 beats-per-minute
(bpm), the heart rate of one may vary from 59 to 61, while another’s swings broadly from 50 to 70
bpm.
Several studies have shown that low heart rate variability correlates with a higher-than-normal risk of heart attacks and other heart conditions, particularly when the slowing occurs in the component of the heart rate known as the low spectral band. In the February 1998 issue of the scientific paper
Bioelectromagnetics, Sastre’s team reported a slowing in the low spectral band among men exposed to magnetic fields that cycle on and off every 15 seconds for an hour at a time.
When David Savitz, [ref. 45] an epidemiologist at the University of North Carolina at Chapel Hill, learned of the findings, he invited Sastre to help him sift through data on heart disease deaths within a group of 138,903 male electrical utility workers from five US companies over the period 1950-1988. The two researchers and their team now have reported a comparison of these data with men in
low-EMF occupations.
It is evident from the data that men in trades exposed to high EMFs – such as line men and power plant operators – were more likely to have died from heart attacks and heart conditions related to abnormal
rythms, or arrythmias. Moreover, risk of death from these conditions climbed as average EMF exposure increased. Savitz notes that men in the highest risk group tended to have worked in EMFs at least twice as high as those people typically encounter in their homes. Men in the uppermost category had a mortality rate 1.5-3.3 times higher than males in
low-EMF occupations.
"These data suggest a possible association between occupational magnetic fields and arrythmia-related heart disease", the researchers concluded in the January 15, 1999 American Journal of
Epidemiology. Savitz now plans to follow up with more detailed studies, perhaps simultaneously monitoring heart rate variability and EMFs among electricians at work.
Presently, research is ongoing at the Catholic University of America
(CUA) in Washington, D.C. showing that chicken embryo hearts produce stress proteins when exposed to pulsed and sinusoidal
EMFs. When repetitively exposed, the chicken embryos hearts starts down-regulating their stress response which is, in effect, a defense mechanism. When down-regulated chicken embryo hearts are exposed to inoxia condition (a simulated heart attack), the chance of surviving that condition becomes substantially reduced.
These results may provide an explanation for the Sastre and Savitz epidemiological findings of elevated heart disease mortality associated with EMF exposures.
On May 20, 1999, Jacobson Resonance Enterprises, Inc., of Boca Raton, Florida, announced via internet-based PRNewswire that preliminary data from studies conducted at the University of Oklahoma Health Sciences Center utilizing the Jacobson Resonator have provided strong evidence that low-level magnetic fields can cause either slowing or speeding of heart rate and associated alterations in conduction from atria to ventricles. For the past several months, Benjamin
Scherlag, Professor of Medicine, and William Yamanashi, Professor of Medicine at the
V.A. Medical Center, in collaboration with Dr. Jacobson have conducted experiments using pico-tesla (10-5
mG) electromagnetic fields applied across the chest in anesthetized dogs. The cardiac impulse from atria to ventricles suggested that these low-level fields (intensity and frequency) were affecting autonomic nerves to the heart.
On May 20,1999 the Associated Press (Washington), published research results from Yale University on treatment of schizophrenia patients with transcranial magnetic stimulation (TMS). The work was presented by Dr. Hoffman, deputy medical director of the Yale Psychiatric Institute, at the annual meeting of the American Psychiatric Association. Schizophrenia patients, whose medication could not stop the imaginary voices in their heads, gained some relief after researchers repeatedly sent a magnetic field into a small area of their brain for a duration of 16 minutes. The magnetic field pulses make brain cells fire messages to adjoining cells. The magnetic pulses are thought to calm the affected part of the brain if they are given as slowly as once per second, according to Hoffman. He and colleagues targeted an area involved in understanding speech, above and behind the left ear, on the theory that hallucinated voices come from overactivity in that portion of the brain.
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