of inhibited activity which lasted until the end of the 10-month exposure period.
Shandala and Vinogradov also studied the effect of an EMF (1-500 µW/cm2, 2.4 GHz, for 30
days) on the phagocytic action of neutrophils in peripheral blood (23). Using guinea pigs, they found
that the percent of killed microbes increased following exposure to 1-10 µW/cm2; and decreased at 50
and 500 µW/cm2; the most pronounced effects occurred at 1 µW/cm2 . EMF-induced alterations in the
complement titer in blood serum were also found. Both immunological indicators returned to normal
within two months of the cessation of irradiation. A similar inhibition of antibody production was
found in rabbits following exposure at 50 µW/cm2 (25).
In later studies, Shandala et al. reported a significant disturbance in the immunological system
of rats exposed intermittently to 500 µW/cm2 for 30 days (26): blast cells in peripheral blood, and the
rosette-forming cells in the spleen and thymus were both altered following EMF exposure.
EMFs have been reported to alter the response of immunocompetent Iymphocytes (27, 28).
Mice, exposed intermittently to 500 µW/cm2 2.95 GHz for 6 and 12 weeks, were challenged with an
injection of sheep red blood cells and the immune response was characterized by the number of
Iymphocytes and plasmocytes in the Iymph nodes. In the 6-weeks exposed animals, the time course of
the antibody-forming cells population was significantly different from that of the controls; the
maximum difference occurred 6-8 days after injection of the antigen, and the effect was no longer
observed after 20 days (27). Exposure for 12 weeks prior to injection resulted in no difference in
immune response as compared to the controls, indicating that the mice had become adapted to the field.
The immunological reaction of guinea pigs exposed to an atmosphere of formaldehyde or
carbon monoxide was altered when the animals were pretreated for 1 month with an EMF (5-50
µW/cm2, 2.4 GHz, 7 hr./day, for 1 mo.) (28).
B-lymphocytes (responsible for humoral antibody synthesis) and neutrophils are each derived
from bone-marrow stem cells. Czerski et al. reported that guinea pigs subjected to a pulsed EMF (2.9
GHz, 1000 µW/cm2, 4 hr./day for 14 days) exhibited an abnormal circadian rhythm of bone-marrow
stem-cell mitoses (30). In a comparable study involving guinea pigs, it was found that the EMF altered
megakaryocytic activity in the bone marrow (29); it stimulated increased levels of megakaryocyte
destruction, and a compensatory proliferation of megakaryoblasts.
Inflammation is a local response of vascular tissue to irritation or injury; it involves the passage
of fluid containing WBCs and proteins from the blood into the tissues. This nonspecific protective
response was found to be susceptible to an EMF (31). An aseptic inflammation in the peritoneal cavity
of mice was induced by the implantation of a glass slip; in the resulting foreign-body reaction the glass
became covered with a cell monolayer, but this response was delayed in mice that had been exposed to
DC magnetic field of 600-3800 gauss.
Since 1976, investigators at Battelle Laboratories have consistently failed to observe 60-Hz
biological effects in many areas including the cardiovascular, hematological and immune-response
systems (32).
Summary
The effects of EMFs on the cardiovascular system include bradycardia, decreased physiological
reserve capacity, and alterations in blood pressure. Heart action may be particularly sensitive to EMF: a
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