Journal of Bioelectricity, 10(1&2), 241-256.
Abstract
A multiphase study was performed to find an effective method to
evaluate electromagnetic field (EMF) sensitivity of patients. The
first phase developed criteria for controlled testing using an environment
low in chemical, particulate, and EMF pollution. Monitoring devices
were used in an effort to ensure that extraneous EMF would not interfere
with the tests. A second phase involved a single-blind challenge
of 100 patients who complained of EMF sensitivity to a series of
fields ranging from 0 to 5 MHz in frequency, plus 5 blank challenges.
Twenty-five patients were found who were sensitive to the fields,
but did not react to the blanks. These were compared in the third
phase to 25 healthy naive volunteer controls. None of the volunteers
reacted to any challenge, active or blank, but 16 of the EMF-sensitive
patients (64%) had positive signs and symptoms scores, plus autonomic
nervous system changes. In the fourth phase, the 16 EMF-sensitive
patients wer rechallengd twice to the frequencies to which they
were most sensitive during the previous challenge. The active frequency
was found to be positive in 100% of the challenges, while all of
the placebo tests were negative. We concluded that this study gives
strong evidence that electromagnetic field sensitivity exists, and
can be elicited under environmentally controlled conditions.
Introduction
Interaction mechanisms that underlie the health and biological effects
of electromagnetic fields (EMF) on humans have been studied by many
authors.1,2,3,4,5,6 This subject was reviewed recently at the 1990
spring meeting of the American Physical Society .7 Choy et. al.8
investigated individuals with multiple sensitivities who reported
reactions to various types of electrical equipment, including power
lines, electronic office equipment such as typewriters and computer
terminals, video display terminals, household appliances (such as
hair dryers), and fluorescent lights.
This paper presents preliminary data on electromagnetic field tests
using a square wave generator to evaluate the EMF sensitivity of
patients reporting such sensitivities under environmentally controlled
and monitored conditions.
Materials and Methods
This study was carried out in four phases.
I. The tests were carried out in an environmentally controlled area
with porcelain-on-steel walls to minimize airborne chemical pollution
which might interfere with the testing procedure. This type of construction
also acted to decrease external electromagnetic fields. Portable
EMF monitoring devices were used to find an area that would minimize
background EMF which might disturb double-blind challenges and interfere
with the testing process. The low-pollution room had a background
of 0-100 V/m electric field and 20-200 nT (Tesla) magnetic field.
The immediate test site of the patients had unmeasurable electrical
fields and magnetic fields in the vicinity of 20 nT.
The major emphasis of this phase of the studies was the evaluation
of the effects of the magnetic field generated by a coil fed from
a sweep/function generator (Model 3030, B.K. Precision Dynascan
Corp.). This equipment allowed us to test square wave frequencies
from 0.1 Hz to 5 MHz.
The patients were tested while they were sitting comfortably upright
in a chair with the generator on a desk at least 2 m away, with
its output connected to a coil 6 cm in diameter and 15 cm tall,
made of 35 m of cable and positioned on the floor with its center
approximately 0.3 m from the feet of the person tested. The mean
values of the alternating magnetic field generated by this arrangement
were approximately 2900 nT at floor level, approximately 350 nT
at the level of the chair seat and patients’ knees, and about
70 nT at hand level. The exposure period lasted approximately 3
minutes per challenge.
Before the EMF challenge, blood pressure, pulse rate, respiratory
rate, temperature, sign and symptom scores, and autonomic nervous
system functions were tested. The autonomic nervous system function
was tested with a binocular iriscorder (Model C2515, Hamamatsu Photonics),
which measured pupil area, time at which constriction and dilation
occurred, and rate of constriction/dilation.9
All patients had been previously evaluated and treated for biological
inhalant, food, and chemical sensitivities in order to minimize
possible confusion from coexisting problems. The patients were stabilized
on a healthy diet in a constant low-pollution environment. In addition,
they had their overall body load reduced and stabilized in a controlled
environment.
II. This was a single-blind screening of 100 patients who cornplained
of being EMF-sensitive. They were challenged under low-pollution
conditions using the sweep/function generator at 0.1, 0.5, 1, 2.5,
5, 10, 20, 40, 50, 60, and 100 Hz; then at 1, 5, 10, 20, 35, 50,
75, and 100 KHz; and finally at I and 5 MHz. There were twenty-one
active challenges and five blanks (placebos) per person, giving
a total of 2600 challenges. When the number and/or intensity of
symptoms were 20% over baseline, the result was considered positive,
and were recorded as such under the various criteria used. A change
in the iriscorder readings more than two standard deviations from
baseline was also recorded as a positive result.
III. Twenty-five patients who were found to be positive in phase
II challenges and who had no more than one placebo reaction were
then selected for a third phase of the study. In addition, 25 healthy
naive volunteers were challenged. Double-blind EMF challenges and
placebos using the aforementioned parameters were performed. There
were 1300 total challenges, of which 1050 were active and 250 were
blanks. The tests averaged 21 active frequencies and 5 blanks per
subject.
IV. Sixteen patients who reacted in phase III were then rechallenged
on two separate occasions in a double-blind manner, using only the
frequencies to which they had responded most strongly. For each
subject, the frequency of maximum sensitivity was inserted randomly
into a series of 5 placebo challenges. Thus, there were a total
of 32 active challenges and 160 blanks.
Results
Phase I. The EMF measurements were quite reproducible. We found
that the lights. and air handling equipment had to be off during
the tests because of their electromagnetic field output. Baseline
studies on patients were completed without remarkable result.
Phase II. Of the total of 100 patients tested in the single-blind
study, 50 reacted to several of the placebos in addition to the
active challenges, and were excluded from further study. Twenty-five
subjects who did not react to any active challenges were also excluded.
A final 25 subjects who did react to active challenges, but not
to blanks, were selected for the third phase of the study (Table
1).
Phase III. The 25 subjects selected from phase II were rechallenqed,
and 16 (64%) reacted positively to the active challenges. The total
number of positive reactions to the 336 active challenges in the
16 patients was 179 (53%), as compared to 6 positive reactions out
of 60 blanks (7.5%). There were no reactions to any challenge, active
or placebo, in the volunteer group of naive subjects (Table 2).
When evaluating frequency response, 75% of the 16 patients reacted
to 1 Hz, 75% to 2.5 Hz, 69% to 5 Hz, 69 % to 10 Hz, 69% to 20 Hz,
and 69% to 10 KHz (Table 3). No patient reacted to all 21 of the
active frequencies in the challenges. The average was 11 reactive
frequencies per patient, with a range of 1 to 19 positive responses.
The principal signs and symptoms produced were neurological (tingling,
sleepiness, headache, dizziness, unconsciousness), musculoskeletal
(pain, tightness, spasm, fibrillation), cardiovascular (palpitation,
flushing, tachycardia, edema), oral/respiratory (pressure in earss
tooth pains, tightness in chest, dyspnea), gastrointestinal (nausea,
belching), ocular (burning), and dermal (itching, burning5 prickling
pain) (Table 4). Most reactions were neurological.
Phase IV. In the 16 patients again rechallenged in a double-blind
manner, using only the single frequency to which they were most
sensitive, all reported reactions to the active frequencies when
challenged. None reacted to the placebos (Table 5). Signs and symptoms
in all 16 patients were positive as was the autonomic nervous system
dysfunction, as measured by the iriscorder (Table 6, Figure 1).
Examples of changes were a 20% decrease in pulmonary function and
a 40% increase in heart rate. In the 16 patients with positive reactions
to EMF challenges, two had delayed reactions; gradually became depressed
and finally became unconscious. Eventually, they awoke without treatment.
Symptoms lasted from 5 hours to 3 days.
Discussion
Since it has been found that electromagnetic fields can affect health,
researchers have investigated these phenomena in vivo and in vitro,
in animals10,11,12 and humans.1,2,3,4,5,6,7 No individual had been
specifically challenged in an attempt to reproduce acute symptoms
until Smith and Monro5 followed by Choy, Monro, and Smith,8 who
used a series of oscillators of varying frequency to trigger symptoms
in electrically sensitive patients. We modified this procedure by
developing controlled environmental area, where baselines were constantly
monitored for particulates, pollutants, and extraneous fields. Here,
controlled EMF output was applied so that data would be more reproducible.
Several factors have led us to believe that we have reproducible
results. Meticulous construction of environmental rooms made a great
difference in the reproducibility of test results. Prior to the
use of such facilities and careful monitoring, a variety of factors,
such as diet, exposure to chemicals, EMF, or dust gave rise to symptoms
which would have been mistaken for placebo reactions. Such effects
were minimized here, as evidenced by the sinail number of placebo
reactions. A few patients reacted to the fields generated by the
monitoring devices (Iriscorder, EKG, and computers) and had to be
dropped from the study as too fragile for accurate analysis. Some
patients reacted to the fields generated by the fluorescent lights,
and others did not present the same signs and symptoms at each challenge,
even though the reactions were significant when contrasted with
the blank responses. The Iriscorder data were objective, however,
and were always reproducible (Figure 1).
We also noted that patients sometimes had delayed or prolonged responses.
Therefore, care had to be taken to be certain that the patient had
returned to baseline before the next challenge. This carry-over
was first noted when evaluating responses to placebo challenges.
Such a response could usually be explained and eliminated by use
of longer intervals between challenges.
In this study, of the 100 patients who expressed suspicion of EMF
sensitivity, 75 actually responded to fields, whereas none of the
controls did. Of the 75, 25 had no reactions to blanks, whereas
50 did, and thus were discarded from the study; even though we felt
that some of the reactions to blanks might be evidence of delayed
reaction to previous frequencies, or prolonged response to the previous
positive challenge, as well as true placebo reactions.
We learned that challenge with 21 frequencies was impossible on
many sensitive patients. They were often unwell for several hours
or days, which confused the data from repeat challenges on subsequent
days. Hence, we selected the one frequency of maximum sensitivity
for repeat challenges in the phase IV studies.
When one compares the various groups to controls, it is clear that
there is a group of patients who have unstable response systems
which appear different from those of the individuals who acted as
controls. These studies show that EMF sensitivity could be elicited
under environmentally controlled conditions. As a result of the
weak field levels and short exposure time, the responses were mild
except in two patients whose symptoms were so severe (e.g., drop
attack, severe itching) that they received intravenous vitamin C,
magnesium, and oxygen as a result of the prolonged and delayed reactions.
Signs and symptoms appeared similar to those seen in food or chemically
sensitive patients at the Environmental Health Center-Dallas, and
included neurological, musculoskeletal, cardiovascular, respiratory,
gastrointestinal, dermal, and ocular changes. The neurological symptoms
were most comon. Similar responses have been recorded by others
in the literature.5,6,7,6,13,14 In 1972, after the Soviets reported
that electrical utility workers were suffering from listlessness,
fatigue, and nausea, Subrohmangam and coworkers13 investigated and
reported decisive changes in cardiac function and bioamine levels
when pulses of 0.01 and 0.1 Hz were used. They found significant
changes in the hypothalamus in response to the EMF fields.
In these studies, the preponderance of reactions occurred at one
to 10 Hz, which accords well with their observations. However, many
reactions also occurred at 50 and 60 Hz, as well as some up to 5
MHz. We conclude that in any given individual susceptibility may
develop to any frequency and produce reactions.
Static magnetic fields are known to cause increased blood pressure
on some individuals.14 Choy and coworkers8 found that EMF reactions
in EMF sensitive patients were not limited to the nervous system,
but occurred in the same systems as in these studies, which basically
corroborate theirs, though neurological symptoms predominated in
our experiments.
Over the past 30 years, numerous investigations with animals and
a few epidemiological studies of human populations have been devoted
to assessing the relationship of microwave exposure to cataract
development. The severity and speed of formation depends not only
on intensity, but also on wavelength and duration of exposure.16-21
McCally et al.22 reported damage to corneal epithelium in Cynomolgus
monkeys after 2.45 GHz irradiation for 6everal hours at only 20-30
mW/cm2 (CW) or even 10-15 mW/cm2 with pulsed fields. Therefore,
the results of Paz23 strongly suggests that the potential for eye
injury exists in surgery where EMF fields are present.
In our experience, the patients’ clinical responses could
not always be reproduced completely, but the objective Iriscorder,
EKG, and respirometer could be. However, the responses were definitely
different from controls or placebo challenges. In our experience
over the years, we have found partial reproduction of symptoms on
repeat challenge to be as significant as total reproduction. Therefore,
significant differences from controls in objective ineasurementa
were deemed valid.
There are several explanations for lack of exact reproducibility.
These are the following: (a) the patients’ total body loads
were different at different exposure periods. For example, some
patients may only respond to EMF when in a reactive hypersensitive
state;5,8 (b) tissue resistance could influence the effect of the
EMF. Zimerman24 reported that electrical resistance of skin decreased
with increasing temperature and increased with progressive drying,
as might be expected; (c) injections of antigen neutralizing substances
prior to test may have reduced the response to EMF. One patient
with asthma was sensitive to high voltage power lines a well as
low voltage house wiring. He experienced muscle spasms in head,
neck, arms, and legs. This patient was also sensitive to dust, weeds,
dust mites, and some foods. He reacted in our tests to 2.5 and 60
Hz and to 5 and 50 KHZ with tightness in the chest. He then received
an antigen shot to neutralize his hypersensitivity reactions. !
Five months later, he was unreactive to EMF; (d) weather changes
might affect the results, since we know that the weather can influence
the propagation of EMF, as may alterations in the geomagnetic fields.
Since humidity, pollution, temperature, etc. can affect resistance
and total body load, weather should perhaps affect the results.
Adverse weather (inversions, for example) may increase pollution
load, while good weather lessens it. There is some evidence of resonance
between geomagnetic fields and an applied ac magnetic field,25 which
implies that the results may depend in part at least upon the strength
and orientation of the geomagnetic field in the test area; and (e)
different wave forms might cause different responses. In these experiments,
we used only square wave inputs to the coils. Consequently, we do
not know whether other wave forms (sine, sawtooth, triangular, etc.)
might induce different types or intensities of reactions.
Thus far, definitive information has not been sufficient to identify
a plausible mechanism for EMF interactions with biological tissue.
Interactions appear to take place at the cell surface, perhaps acting
on receptor sites and altering ion and molecular transport across
the membranes.25 Further work remains to be done in the field.
It is clear that EMF sensitivity is a real phenomenon in some environmentally
sensitive patients, because some had consistent reactions while
none of the controls did. This study must be considered as only
preliminary, but the evidence clearly points to sensitivity in some
people.
In conclusion, it is evident that EMF testing is
at a rudimentary stage; but clearly EMF sensitivity exists and can
be elicited under environmentally controlled conditions. Further
studies are needed to investigate the effects of EMF fields on human
health.
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