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     MindNet Journal - Vol. 1, No. 61a * [Part 1 of 2 parts]
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     V E R I C O M M / MindNet         "Quid veritas est?"
================================================================

The views and opinions expressed below are not necessarily the
views and opinions of VERICOMM, MindNet, or the editors unless
otherwise noted.

Permission is given to reproduce and redistribute, for
non-commercial purposes only, provided this information and the
copy remain intact and unedited.

Editor: Mike Coyle 

Assistant Editor: Rick Lawler

Research: Darrell Bross

Editor's Note:

I am usually reticent to express my personal opinions about
a paper such as this. It seems, to me, to be better to just let
the information speak for itself and allow the reader to come to
their own opinion about its veracity. However, the following
article about GWEN, obviously written by the government agency 
that is responsible for its creation, is such an egregious 
example of disinformation, obfuscation, and selective
referencing, that I feel I owe my subscribers a comment and
explanation.

The serious, and adverse health effects associated with exposure
to even low-levels of RFR, which are largely discounted by this
article, are well documented as a result of laboratory
experiments, case history studies, and statistical studies done
by many scientists and doctors. Below you will find a few
excerpts from this article followed by rebuttals that directly
contradict these excerpts.

...stated within:

"A number of so-called "nonthermal" effects have been described
in the scientific literature in connection with RFR exposure of
laboratory animals and animal tissue at levels equal to or less
than 0.4 W/kg (EPA 1986). These effects, involving the cellular,
hematologic, reproductive, nervous systems, and others, are
summarized in a review by Cahill and Elder (1984). The
significance of these effects for public health is not clear,
partly because the mechanisms responsible for them are not
known."

...rebuttal:

"...DARPA at the Institute for Defense Analysis...`certain events
presumed to the threatening to the national interest served as
the basis for ARPA's support for Project Pandora', and funds were
given to Walter Reed [Medical Research Institute] early in 1965
`to evaluate the threat since it appeared to have strong
behavioral and biomedical implications'...`cytogenic and
histological studies of the brain suggested that comparable
energies were damaging tissue' 
  
  - _The_Zapping_of_America_ by Paul Brodeur, 1977, pg. 123.

...stated within:

"_Cataracts_. It has been asserted in newspapers and other popular
media that microwaves potentially cause cataracts. Scientific
studies have indicated that microwaves can cause cataracts in
experimental animals, but only if incident continuous-wave power
densities are high..."

...rebuttal:

"...the case received prominent mention in the bureau's [Bureau
of Radiological Health] 1969 annual report to Congress. When
Carpenter described it a the fifth annual symposium of the
International Microwave Power Institute, which was held in
Scheveningen, in the Netherlands, on October 7, 1970, he stated
that it provided a `unique example of bilateral cataracts
resulting from low-level microwave radiation.'" 

  - _The_Zapping_of_America_ by Paul Brodeur, 1977, pg. 68.

...stated within:

"_Birth Defects_. Birth defects (technically, teratogenesis) and
developmental abnormalities after birth are always of public
concern... Teratogenic studies associated with RFR have used a
variety of animal models. The results indicate that a threshold
of heat induction or temperature increase must be exceeded
before teratogenic effects are produced. For the SARs associated
with human exposure to GWEN RFR, there would be no detectable
heating, so birth defects would be extremely unlikely."

...rebuttal:

"That microwave radiation might have genetic effects had first
been discovered back in 1959 by Dr. John H. Heller...at the New
England Institute for Medical Research, in Ridgefield Conn., who
observed gross chromosomal abnormalities in garlic-root tips that
had been irradiated with microwaves at power levels far below
those necessary to produce heat...in August 1975, members of
Electromagnetic Radiation Management Advisory Council, OTP, &
DoD met to review the findings of research pertaining to the
genetic, hereditary, growth, and developmental  effects of
microwave and radio-frequency radiation, they learned that in
eight out of fifteen projects low-level radiation had produced
effects and changes in the test animals or genetic material." 

  - _The_Zapping_of_America_ by Paul Brodeur, 1977, pg. 90.

...stated within:

"_Endocrine System Effects_. Exposure of animals to RFR has
produced... There do not appear to be any effects clearly
demonstrated to be associated with nonthermogenic stimulation of
the endocrine system or the associated parts of the CNS."

...rebuttal:

"Soviet investigators also turned up a great number of endocrine
responses to radio-frequency radiation, including increased
thyroid activity, slight enlargement of the thyroid gland,
sterility, and decreased lactation in nursing mothers." 

  - _The_Zapping_of_America_ by Paul Brodeur, 1977, pg. 37.

I could go on and on, but I think you see my point. Please keep
this in mind as you read this document. I have also included
below a few references excerpted from _Cross_Currents_ by Dr.
Robert O. Becker that document the adverse effects of RFR. 

Aurell, E., and Tengroth, B. _Acta_Ophthalmologica_ 51 
(1973):764. Report that microwaves can produce cataract at 
nonthermal levels and can damage the retina itself.

Birge, R., et al. _Journal_of_the_American_Chemical_Society_
109(1987):2090. Report that certain chemicals in the retina
absorb microwaves to a high degree.

Delgado, J.M.R., et al. _Journal_of_Anatomy_ 134 (1982):533.
Reports on developmental defects in chick embryos exposed to
various ELF frequencies.

Garfinkel, I., and Savokhan, B. _Annals_of_the_New_York_Academy_
_of_Sciences_ 381 (1982):I. Report that the incidence of brain
tumors rose between 1940 and 1977.

Heller, J.H., and Teixeira-Pinto, A.A. _Nature_ 183 (1959):905.
First report on the production of chromosomal abnormalities
by fields at 27 MHz.

Liboff, A, _Science_ 223 (1984):818. Report that a wide range 
of frequencies in the ELF-VLF range could increase the rate
of DNA synthesis in dividing cells.

================================================================

GROUND WAVE EMERGENCY NETWORK (GWEN)

Document courtesy of Julianne McKinney,  
Electronic Surveillance Project.

September 1995

----------------------------------------------------------------

Ground Wave Emergency Network (GWEN)

---

3.11 HEALTH

3.11.1 Definition of Resource

   Aspects of the GWEN program that might affect the health of 
the general public residing in the vicinity of GWEN facilities or
potentially exposed to GWEN operations are related to exposure to
radio frequency radiation (RFR). All radio transmission antennae
are sources of RFR. The GWEN system would generate RFR from a
299-foot, low-frequency (LF) antenna and an ultrahigh-frequency
(UHF) antenna located at each relay node (RN) station, and from a
UHF antenna located at each input/output (I/O) station.
   The oscillation of current and voltage in a transmitting 
antenna results in the radiation of an outward-traveling field, 
or electromagnetic wave. By encoding information into this wave,
messages can be transmitted to a receiving station in a manner
analogous to AM, FM, and TV broadcasting and reception. The
electromagnetic wave consists of an electric field, the E-field,
and a magnetic field, the H-field. These electromagnetic waves
constitute the RFR.
   The region beyond the distance of a few wavelengths of any
transmission is known as the far field. The wavelengths for GWEN
LF transmissions range from 1.7 to 2 kilometers; thus, the far
field refers to the region beyond several kilometers from the RN
stations. The region within a few wavelengths of the
transmitting antenna is referred to as the near field. The
electromagnetic field within this region is more complicated than
in the far field. In addition to the primary propagating wave,
there are nonpropagating fields which tend to dominate the near
field. Because these nonpropagating fields decrease rapidly with
distance, they become insignificant in the far field.

3.11.2 Issues and Concerns

   Although RFR is referred to as radiation, it does not cause
ionization and should not be confused with radiation from
radioactive sources. In general, RFR is associated with
electromagnetic waves with frequencies ranging from
approximately 10 kilohertz (kHz) to 300 gigahertz (GHz).
Electromagnetic waves with higher frequencies than radio waves
are, in ascending order of frequency, infrared waves, visible
light, ultraviolet waves, X-rays, and gamma rays.
   Electromagnetic waves propagate energy in "packets" called
photons. The energy of a photon is directly proportional to the
frequency of the radiation. When the photon energies equal or
exceed the binding energies of electrons to atoms, the radiation
is capable of ionizing atoms and breaking electron bonds in
biomolecules, thereby disrupting biochemical processes and
causing genetic and other damage in biological organisms.
Ultraviolet waves, X-rays, and gamma rays, are ionizing. However,
the photon energies associated with the highest radio frequencies
are several orders of magnitude lower than the weakest chemical
bonds and they cannot ionize atoms or disrupt chemical bonding.
   Thus, RFR is nonionizing and does not create the same effect 
as radiation generated by radioactive sources. Its primary effect 
in biological organisms is to agitate molecules, that is, 
generate heat. At intensities that fall within present exposure 
standards, the rate of heat generation is negligible or is within 
the thermoregulatory capabilities of mammals and birds.
   There have been reports of some cases of accidental 
occupational exposure to RFR intensities that exceed present 
safety limits. In addition, the Environmental Protection Agency 
(EPA) has found that levels of field intensities in the FM and 
TV-broadcast bands exceed present exposure limits at certain 
sites that are accessible to the general public. Because of these 
few cases, some members of the public may perceive that there is 
a high risk associated with RFR regardless of intensity or 
frequency. Public concerns are centered on the potential for 
effects on humans due to both long- and short-term exposure to 
RFR at GWEN frequencies and exposure levels. These concerns may 
include the potential for shock hazards, birth defects, and 
cancer.

3.11.3 Regulatory Setting

   No federal, state, county, or municipal regulations exist for 
RFR exposure in the GWEN LF band (150 to 175 kHz). In July 1986, 
as part of its charge under federal law to develop RFR protection
guides, the EPA published proposed alternatives for controlling
public exposure to RFR and requested written comments. Other
national and international agencies have published guidelines for
RFR safety.
   _American_National_Standards_Institute_ (ANSI) has set safety
levels for human exposure to RFR in the frequency range of 300
kHz to 100 GHz (ANSI, 1982), ANSI concluded that the reliable
evidence of hazardous effects on animals is associated with
whole-body-average specific absorption rates (SAR) above 4
watts/kilogram (W/kg) in animals. Using a safety factor of 10,
the exposure limit was set at 0.4 W/kg. Since SAR is
frequency-dependent in a manner that is species-specific, the
power density limits that correspond to 0.4 W/kg vary with
frequency. At resonant frequencies for humans (see section
3.11.6.2), this value of SAR corresponds to a power density of 1
milliwatt per square centimeter (mw/cm2). This limit on power
density was specified for the frequency range of 30 to 300 MHz
to include all possible resonant conditions for humans. The
limit on power density for frequencies below this range can be
increased inversely as the second power of the frequency while
still maintaining a limit of 0.4 W/kg on the SAR. However,
because there's a potential for shock and burns at high power
densities, the ANSI subcommittee limited the power density to 100
mw/cm2 for frequencies below 3 MHz, extending down to 300 kHz.
Using the assumption of plane waves, this power density limit
corresponds to an E-field intensity of 632 volts per meter (V/m)
and to an H-field intensity of 1.58 amperes per meter (A/m).
While the ANSI standard would limit the SAR value to 0.4 W/kg
averaged over the whole body, it allows a spatial peak (local)
value of 8 W/kg averaged over any one gram of tissue. SARs,
power densities, and squares of field intensities are averaged
over any 6-minute period. The ANSI subcommittee did not provide
any guidance for frequencies below 300 kHz; therefore, ANSI does
not cover the GWEN LF band. The ANSI standard is applicable to
the control of occupational and non-occupational exposures.
   _International_Radiation_Protection_Association_ (IRPA) 
provides interim guidelines on limits of exposure (IRPA 1984). 
While IRPA's occupational limits at resonance are the same as 
ANSI's, the limit for the general population is based on a safety 
factor of 50 relative to 4 W/kg, or 5 relative to 0.4 W/kg. The
whole-body average SAR is limited to 0.08 W/kg, which
corresponds to a power density of 0.2 mw/cm2 in the range of
human resonant frequencies. The limit on the local SAR for the
general population is reduced to 0.8 W/kg. As with the other
standards, the power density limit rises as the frequency
decreases from resonance. The limit for exposure to the public
in the 100 kHz to 1 MHz frequency range is a power density of 2
mw/cm2, with corresponding limits to E-field and H-field
intensities set at 87 V/m and 0.23 A/m, respectively. These
limits would apply to the GWEN LF transmissions.
   _National_Council_on_Radiation_Protection_and_Measurements_ 
(NCRP 1986) recently recommended RFR limits for the public. 
These limits are similar to IRPA's limits for the public in that 
they use the same safety factor to limit whole-body average SARs 
to 0.08 W/kg and local SARs to 1.6 W/kg. For frequencies below 
1.34 MHz, the NCRP limits the power density to 100 mw/cm2, which 
is higher than the IRPA limit but the same as the ANSI limit. The
NCRP does not provide guidance for frequencies below 300 kHz;
therefore, their standards do not cover the GWEN LF band.
   _EPA_ (1986) has Proposed three alternatives for limiting 
public exposure to RFR. Two alternatives are similar to the other
standards: limiting whole-body-average SARs to either 0.4 W/kg or
0.08 W/kg for frequencies above 3 MHz. The third alternative
(EPA option 1) is the most restrictive, as it limits whole-body
average SARs to 0.04 W/kg for frequencies above 3 MHz. Below 3
MHz this option would limit E-field intensity to 87 V/m and
H-field intensity to 0.23 A/m. While this option is more
restrictive than the IRPA standard for frequencies greater than 3
MHz, it is equal to the IRPA standards for lower frequencies. The
EPA proposal does not specify limits on local SAR values, but it
does note that the exposure limit under its option I will
substantially reduce local heating effects of RF body currents
by keeping the local SAR to less than 4 W/kg.

3.11.4 Approach to Analysis

   In order to assess possible RFR biological hazards, the 
pertinent literature on electric shock, radio frequency (RF) 
burns; and bioeffects related to absorbed energy was reviewed. 
Findings that might be relevant to GWEN frequencies were 
evaluated by comparing the RF intensity levels studied to actual 
measured levels at GWEN facilities. The objective of the analysis 
was to determine the extent of the zone around an RN's antenna 
base that would need to be controlled in order to prevent public
exposure to RFR levels that exceed safety standards.

3.11.5 Data Sources

   The present level of knowledge regarding biological effects of
RFR was reviewed in an EPA report by Elder and Cahill (1984) and
a report prepared for the USAF School of Aerospace Medicine
(USAFSAM) by Heynick and Polson (1983). The latter report was
updated and expanded by Heynick (1986) and will be reissued.
Information is also summarized by Polk and Postow (1986), Elder
(1986), and in the EPA announcement of the proposed alternative
guidelines for RFR protection (EPA 1986). Two recent reports
prepared for USAFSAM document possible hazards in the frequency
range of 10 kHz to 3 MHz, which brackets the GWEN LF antenna
frequencies (Gandhi et al. 1985; Guy and Chou 1985).

3.11.6 Existing Conditions

   The potential health effects to humans associated with 
exposure to RFR can be divided into two major categories:

   Electric shock and RF burns resulting from contact between
grounded people and ungrounded objects. Bare feet on wet ground
would provide maximum grounding. Footware (shoes) reduce the
level of grounding and provide some measure of protection. The
analysis below assumes an individual who would be fully
grounded.

   A wide range of effects resulting from the energy absorbed by 
the body.

3.11.6.1 Electric Shock and RF Burns

   Electric shock and RF burns can occur because of voltages 
induced by RFR below 3 MHz, and particularly below 200 kHz, in 
ungrounded conductive objects, such as vehicles, fencing, metal 
roofing, and guy wires. When an individual that is electrically 
grounded makes contact with an ungrounded conductive object in 
an RF field, currents may then flow through the individual's 
body. The amount of current flow depends on how well the 
individual is electrically grounded, the impedance between the 
ungrounded object and the individual, and the voltage and charge 
of the object induced by the RF field.
   At low-intensity RF fields, a grounded individual might
experience a tingling or warm feeling in the fingers, hands,
wrists, or ankles when in contact with an ungrounded conductive
object. At higher field intensities, an individual might
experience an electric shock as contact was made with the
ungrounded object. Electric shock can also result when an
ungrounded individual in a high-intensity RF field comes into
contact with a grounded object. If the flow of current is large
enough, it can cause localized heating of body tissue resulting
in an RF burn. RF burns can also be caused by direct contact
with an RF source (e.g., an antenna) or an  uninsulated
transmission line. Direct contact with a GWEN antenna is
discussed under system safety.
   Two independent groups of researchers have recently studied 
the shock hazard from objects in RF fields with frequencies of 
10 kHz to 3 MHz (Guy and Chou 1985; Gandhi et al. 1985). The
results were based on actual measurements at RF antennae and
experimental measurements on several hundred subjects. Since the
shock hazard is due to the electric, rather than magnetic,
component of RF fields, thresholds were stated in terms of the
intensity of the E-field. Perception thresholds corresponded to
the mean lowest current (measured in a laboratory experiment) at
which the subjects reported any sensation at all, usually mild
tingling or pricking at frequencies below 100 kHz and faint
warmth at higher frequencies. The pain thresholds corresponded
to the mean lowest current at which the subjects reported a very
uncomfortable sensation and did not want to continue touching the
electrode. Chatterjee et al. (1986) believe that the cause for
sensations at frequencies above 100 kHz is an increased energy
density, or SAR, in the hand or wrist.
   For the frequency range of the GWEN LF antenna (150 to 175 
kHz), Gandhi et al. (1985) and Chatterjee et al. (1986) 
calculated perception thresholds for grounded 10-year-old 
children in finger contact with large ungrounded metallic objects. 
These thresholds were 65 V/m for a fork-lift truck, 120  V/m for a 
van, and 250 V/m for a 50-foot section of fence. Calculated 
perception thresholds for electrically grounded adults touching 
those objects were about 40 percent higher.
   Calculated perception and pain thresholds for persons in 
grasping contact were higher than for persons in finger contact. 
For example, the perception threshold for a 10-year-old child in
grasping contact with a van was 430  V/m, as opposed to 120 V/m
for finger contact. However, Chatterjee et al. (1986) report
that perception thresholds for a tapping contact with the finger
was about 10 percent lower than for continuous finger contact.
Also, they report that, for frequencies greater than 100 kHz, a
continuous contact at the perception threshold produced a
sensation of pain within 10 to 20 seconds.
   In addition to causing perception or pain, the flow of current
through the body could be sufficiently high to produce some
damage to tissues. Gandhi et al. (1985) addressed this by
calculating the E-field required to produce a whole-body-average
SAR of 0.4 W/kg and a local SAR of 8 W/kg of a grounded
individual in grasping contact with a van. These SAR values are
the limits set by ANSI and are a factor of 10 below those that
cause harmful effects. Gandhi et al. determined that, at GWEN
frequencies, an E-field of 300 V/m would be required to produce a
whole-body-average SAR of 0.4 W/kg, and 95 V/m would be required
to produce a local SAR of 8 W/kg in the wrist of a 10-year-old
child; these values would be about 40 percent higher for adults.
   Gandhi et al. (1985) also considered the flow of current 
through a grounded individual not in contact with a metallic 
object or in the vicinity of one. They calculate that at GWEN 
frequencies, the E-field required to produce a whole-body average 
SAR of 0.4 W/kg would be 9,000 V/m, and the E-field required to 
produce a maximum local SAR (in the ankle) of 8 W/kg would be 
2,000 V/m.
   These calculations of the E-field intensities required to 
produce the specific SAR values reported were based on the 
assumption that the RFR is continuously emitted. When the RFR is 
not continuously emitted, the SAR values will be lower for the 
same E-field, or, conversely, the E-field must be higher to 
produce the same SAR. This is the case for GWEN, which broadcasts 
with a duty cycle of 28 percent. Since SAR is proportional to the 
square of the E-field intensity, the continuous E-field values 
given by Gandhi et al. may be divided by the square root of 0.28 
to yield discontinuous E-field values for application to GWEN. 
Therefore, the GWEN E-field required to produce a local SAR of 8 
W/kg in the wrist of a child in grasping contact with the van 
would be 180 V/m. (This value is well below the perception 
threshold for a child in grasping contact.) The GWEN E-field 
required to produce a local SAR of 8 W/kg in the ankle of an 
adult not in contact with a metallic object would be 3,780 V/m. 
The GWEN E-field required to produce the IRPA limit of 0.8 W/kg 
for a local SAR would be 1,195 V/m.

3.11.6.2 Effects Due to Absorbed Energy

   The other major category of potential health effects is
associated with energy absorbed by the body when exposed to
RFR. Generally, energy absorption is related to frequency. When
frequency is such that the incident wavelength is much smaller
than the size of the exposed subject, there is poor penetration
and energy is deposited largely on the surface of the subject
(Cahill and Elder 1984; Polk and Postow 1986). For humans, that
corresponds to frequencies greater than about 5,000 MHz. When the
incident wavelength and the subject are the same order of
magnitude, resonance occurs and maximum energy is absorbed. The
resonant frequency varies depending on thc size of the human
body and ranges from about 35 MHz for a grounded adult 5 feet 9
inches tall to about 200 MHz for an ungrounded infant. When the
wavelength is much greater than the subject's size, the
absorptive coupling is inefficient and little energy is absorbed.
This occurs in humans at frequencies lower than about 1 MHz, and
includes the GWEN LF frequency (150 to 175 kHz) with wavelengths
about 1,000 times greater than the size of humans. RFR from the
GWEN UHF antennae (/25 to 400 Mhz) falls in a range just above
resonant frequencies (see section 4.11.1.2).
   The accepted measure of RF absorption is the SAR, which is 
the mass-normalized rate of energy absorption in watts per 
kilogram (W/kg). The SAR depends on the dielectric composition 
and shape of the subject, its orientation with respect to the RF 
field, and the complexity of the radiation, as well as on the 
size of the subject relative to the wavelength. The SAR can be 
estimated by combining the frequency and power density of the RF 
field with the size and dielectric property of the subject 
exposed to the field (Cahill and Elder 1984). Such calculations 
can be performed for humans exposed to the RFR from GWEN. For an 
average man, the _Radio_Frequency_Radiation_Dosimetry_Handbook_ 
(Durney et al. 1978) indicates that the maximum average SAR at 
the GWEN LF band would be approximately 0.0000006 W/kg per 
1 mW/cm2, occurring when the long axis of the body was parallel 
to the E-field polarization. When the body was perpendicular to 
the E-field, the average SAR would decrease by a factor of
approximately 30.
   The maximum value of the E-field from the GWEN LF transmitter
outside the 4-foot fence would be 50 V/m (see section 4.11.1.1).
This is equivalent to approximately 0.66 mw/cm2 (assuming a
plane wave). Therefore, the maximum average SAR in a human
standing in an E-field of intensity 50 V/m would be
approximately 0.0000004 W/kg, assuming continuous RF emission.
Since GWEN broadcasts LF transmissions with a 28-percent duty
cycle, the maximum average SAR at the 4-foot fence would be
approximately 0.0000001  W/kg.
   The maximum average SAR associated with GWEN UHF exposure can 
be calculated in a similar fashion. At the frequency band used 
for GWEN UHF transmissions, the maximum average SAR would be
0.1 W/kg per 1 mW/cm2 (Durney et al. 1978). Since the maximum
exposure to GWEN UHF would be 0.001 mW/cm2 for a 40 percent duty
cycle (see section 4.11.1.2), the maximum average SAR at a GWEN
station due to UHF exposure would be 0.0001 W/kg.
   A number of so-called "nonthermal" effects have been described 
in the scientific literature in connection with RFR exposure of
laboratory animals and animal tissue at levels equal to or less
than 0.4 W/kg (EPA 1986). These effects, involving the cellular,
hematologic, reproductive, nervous systems, and others, are
summarized in a review by Cahill and Elder (1984). The
significance of these effects for public health is not clear,
partly because the mechanisms responsible for them are not known.
Some results are from single studies and have not yet been
verified by duplication (EPA 1986). In some cases, there are
conflicting results as to whether a given effect even occurs. At
this time, it is not yet clear whether low-level nonthermal
effects have an impact on human health. Consequently, the EPA
(1986) concludes that the data are insufficient to assess the
adversity and human health implications of effects observed for
whole-body average SAR below 1 W/kg. However, in light of the SAR
values for humans exposed to RFR from GWEN (less than 0.0000001
W/kg for LF and 0.0001 W/kg for UHF), nonthermal effects are
extremely unlikely.
   A degree of uncertainty exists in extrapolating findings on
animals to humans because of differences in species, exposure
frequencies, and internal distribution of absorbed energy
(Heynick and Polson 1983; Heynick 1986). There is very little
information on RF effects in humans and limited data on
responses of animals at frequencies above 10 GHz and below 10
MHz. However, the use of SAR as an index of exposure has allowed
excellent extrapolation of effects across frequencies, and it is
reasonable to assume that would also be applicable for GWEN
frequencies.
   The health effects related to exposure to RFR have been the
subject of continuing research for about 30 years, and an
estimated 8,000 papers on RFR bioeffects have been published.
Over the past decade great advances have been made in
correlating the observation of effects (or lack thereof) with
the SAR. Although SAR is associated with energy deposition, and
frequently only with thermalization of the RFR energy in tissue,
it also defines the fields existing within the tissues, and is a
useful measure when discussing both thermal and nonthermal
effects.
   Research papers cover a wide range of general topics in the
biological sciences. These include epidemiologic studies of
humans; the possibility of RFR exposure causing cancer or birth
defects, effects on the eye, the nervous system, behavior,
hormone-secreting systems in mammals, and the immune system;
and general biochemical and physiological effects (Heynick and
Polson 1986; Heynick 1986; Polk and Postow 1986). The interested
reader is referred to these publications for more specific
details of representative papers under each biological topic.
The following discussions summarize those reviews.
   The discussion of effects due to absorbed energy is in 
reference to RFR in general. Most of the studies were at UHF and,
therefore, would be applicable to GWEN UHF exposure. The SAR for
GWEN exposure would be several orders of magnitude below the SARs
associated with any reported effects. Therefore, it would be
very unlikely that these effects would result from GWEN UHF
exposure. Although none of the studies were conducted at LF,
assessment of GWEN LF exposure can be made by comparing the GWEN
SAR with the SARs reported in the studies. Since GWEN LF exposure
would be many orders of magnitude below SARs associated with
reported effects, the possibility that there would be any
effects would be very remote.
   _Epidemiologic_Studies_. Although there are relatively few
epidemiologic studies, those that have been performed have
included several hundreds of thousands of individuals. None of
the studies offers clear evidence of detrimental effects
associated with exposure of the general population to RFR.
However, findings of studies performed in the Soviet Union
suggest that occupational exposure to UHF RFR at average power
densities of less than 1 mw/cm2 does result in various
symptoms (which they lump together as "microwave syndrome")
but this is generally not recognized in western medical
practice. The SARs associated with GWEN LF exposure, at
frequencies 1,000 to 10,000 times lower than UHF, would be many
orders of magnitude lower. Thus, even if one accepted the
Soviet findings for UHF frequencies, the likelihood of such
effects at GWEN frequencies and power intensities is remote.
Collectively, the results of the epidemiologic studies do not
provide evidence of the likelihood of any hazard to the general
population from exposure to RFR from GWEN. Exposure to GWEN UHF
would be at power densities of 0.001 mW/cm2 or less (see section
4.11.1.2) which would be two to three orders of magnitude below
the power densities of the observations in the Soviet studies.
   _Cancer_. One frequently expressed concern about RFR is that 
it may cause mutations or cancer. Several studies regarding the
possible mutagenic effects of RFR have been done on bacteria,
yeast, and fruit flies. These studies failed to demonstrate
mutagenic effects that could be attributed to RFR exposure.
Other studies using mice and rats also have failed to provide
evidence of mutagenic effects. Studies on the general health or
the occurrence of cancer in exposed animals have generally
yielded negative results. Extrapolation of these animal studies
to humans indicates that the SAR associated with human exposure
to GWEN RFR is most unlikely to cause mutagenic effects or to
cause cancer.
   _Birth_Defects_. Birth defects (technically, teratogenesis) 
and developmental abnormalities after birth are always of public
concern, especially because, in a few cases, specific (non-RFR)
agents have been shown to cause such effects. Birth defects and
developmental abnormalities also occur naturally at a low rate in
most animal species. Teratogenuc studies associated with RFR have
used a variety of animal models. The results indicate that a
threshold of heat induction or  temperature increase must be
exceeded before teratogenic effects are produced. For the SARs
associated with human exposure to GWEN RFR, there would be no
detectable heating, so birth defects would be extremely unlikely.
   _Cataracts_. It has been asserted in newspapers and other 
popular media that microwaves potentially cause cataracts. 
Scientific studies have indicated that microwaves can cause 
cataracts in experimental animals, but only if incident 
continuous-wave power densities are high, approximately 150 
mw/cm2 or greater. Under such conditions of frequency and power 
density, local SARs in the eye can be so great that significant 
temperature rises occur. Such effects also appear to have a 
threshold; if a critical temperature is not exceeded within the 
eye for a certain duration, no cataracts are formed. Recent 
studies also indicate effects on corneal endothelium in the eyes 
of monkeys exposed to microwaves, but there is no evidence that 
such effects could occur at SARs associated with exposure to 
GWEN RFR.
   _Nervous_System_Effects_. Several types of studies have been
conducted regarding the effects of RFR on the nervous system of
animals. U.S. scientists consider most effects of RFR on the
nervous system to be indirect results of other physiological
interactions, with the possible exception of alterations of
calcium-ion binding in brain tissue. This phenomenon occurs with
amplitude-modulated waveforms for a wide range of carrier
frequencies from extremely low frequency to UHF. However, there
is no evidence that it occurs at power densities below 0.1
mw/cm2, and even if it did, there is no indication that it is in
any way associated with adverse health effects. Other observed
nervous-system effects have included: alteration of the
permeability of the blood-brain barrier, but consistent data
exist only for local SARs that are sufficient to cause heating;
alterations in and damage to some regions of the brains of
hamsters and rats (but not of squirrel monkeys), but, again,
resulting from thermal processes; and alterations of
electroencephalograms (electrical activity of the brain) in
animals, but only when in-dwelling  electrodes were used. The
last effect is the only one that could perhaps apply to the GWEN
system. With modern advances in medical technology, it is
becoming more common (though still rare in terms of absolute
numbers) for patients with certain neurological problems to have
metal electrodes implanted in their brains. Such persons could
be affected by fields within the immediate vicinity of the GWEN
transmitters. However, there are no known reports of anyone
having been affected by RFR as a result of any surgical
implantation to correct neurological problems. All other effects
on the nervous system are unlikely to occur at the SARs
associated with human exposure to GWEN RFR.
   _Behavioral_Effects_. Many experimental studies have been
conducted on the effects of RFR on animal behavior. The results
of such studies are considered particularly important in the
Soviet Union, where they are often held to be evidence of direct
effects of RFR on the central nervous system (CNS). U.S.
scientists do not always agree that behavioral effects
necessarily imply direct effects on the CNS. However, as
behavioral effects are very sensitive indicators of biological
function, they receive appropriate attention in both eastern
European and western countries. Representative behavioral
studies (Heynick and Polson 1986; Heynick 1986) include studies
of effects on reflex activity, RFR perception, effects of RFR on
learning and on performance of trained tasks, interactive
effects of RFR and drugs on behavior, and behavioral
thermoregulation. Studies have been conducted on mice, rats,
rabbits, squirrel monkeys, rhesus monkeys, and humans.
   Soviet claims of effects at low-power densities (equal to or 
less than 0.5 mw/cm2) for long-term exposures have not been
duplicated in similar studies by U.S. researchers. The validity
of the Soviet claims is difficult to assess because of lack of
detail in the reports of the experiments. It is very likely that
behavioral effects could have been seen if in-dwelling
electrodes were used for the animals involved in the Soviet
studies, but it is unknown whether they were.
   RFR is capable of producing alterations in a wide variety of
behaviors of various animals. Except for pulsed RFR, average
power densities required to modify behavior are almost all at
levels of approximately 5 mw/cm2 and above, with corresponding
SARs of approximately 1 W/kg and above. Perception of pulsed
RFR (i.e., microwave hearing) is a peak-power phenomenon, not an
average-power one, and can thereby modify behavior. 
   It is difficult to relate most of the behavioral studies in
animals to humans. All behavioral studies are directly relevant
to the nature of the species being studied, and the conclusions
of a given study do not readily transfer to other species.
Because the SARs needed to cause reported effects are so high,
these studies provide no evidence that exposure to RFR at the
levels that would be emitted outside the fence at GWEN RNs
would likely have adverse effects on human behavior.
   _Endocrine_System_Effects_. Exposure of animals to RFR has
produced somewhat inconsistent effects on the hormone-secreting
(endocrine) system of mammals. In general, the effects appear to
be related to either the heat load associated with the RFR or the
stress induced in the animals by the RFR or, possibly, other
experimental circumstances. Some effects also appear to be
related to alteration of the circadian rhythm by RFR. There do
not appear to be any effects clearly demonstrated to be
associated with nonthermogenic stimulation of the endocrine
system or the associated parts of the CNS.
   Because the reported effects of RFR on the endocrine systems 
of animals are largely ascribable to increased thermal burdens 
and stresses engendered by the experimental situation, there is 
no evidence that such effects would occur in humans exposed to 
the RFR from the GWEN transmitter outside the fence because of 
the extremely low SARs involved.
   _Immune_System_Effects_. The accumulation of reports to date
indicates that RFR has definite effects on the immune system of
mammals. Most of the reported effects were detected after
exposure at SARs about 4 W/kg and higher; a few have been
detected following exposure at SARs as low as 0.2 W/kg. In some
cases, the effects that were observed at higher power densities
were not found at lower power densities, indicating the
possibility of a threshold power density. In most studies, the
mechanisms for the effects seen were not investigated, and the
various reports are somewhat inconsistent. The situation is
complicated by the complexity of the immune system and the
variety of test procedures used.
   The existing evidence indicates that some of the 
immune-system effects are probably related to the effect of RFR 
on the endocrine system resulting from adaptation to stress. 
The mechanisms and significance of such effects are not yet
understood, and individual findings have not been independently
verified. There is currently no evidence that relates RFR
effects on animals' immune systems to effects on the immune
system of humans chronically exposed to the levels of RFR that
would be experienced outside thc fenced area of a GWEN RN. In
addition, because of the extremely small SARs involved, there is
no evidence to suggest that such effects would be hazardous to
human health.
   _Biochemical_and_Physiological_Effects_. The literature on
biochemical and physiological effects associated with RFR is
extensive. Many of the reported effects are associated with
other events (e.g., changes in hormonal levels or stress
adaptation), and some do not have clear medical significance.
   The thermal basis for most of the reported physiological and
biochemical effects of exposure of intact animals to RFR is
evident. The investigations with nonhuman primates are most
significant with respect to possible hazards of human exposure
to RFR because the anatomies and physiological characteristics
of primates are closest to those of humans. The results with
rhesus monkeys showed that exposure to RFR at frequencies in the
range of 3 to 30 MHz at average-power densities of about 100
mw/cm2 were well within the thermoregulatory capabilities of
this species. Also noteworthy were the negative findings of
blood-chemistry assays performed on rhesus monkeys one to two
years after exposures to such high-power densities. The
thermoregulatory system of squirrel monkeys were also observed
to effectively compensate for RFR exposure.
   The investigations involving exposure of intact, smaller 
species of mammals to RFR have yielded both positive and 
negative results. Some of the positive findings are also clearly 
due to the additional thermal burden posed by the RFR. Other 
results, showing decreased food intake and lower blood glucose 
levels in rats, indicate the existence of a SAR threshold of 
about 1 W/kg or higher for such effects.
   One physiological concern is whether exposure of humans to 
RFR can affect their heart function. In early work on this 
subject with excised turtle, frog, and rat hearts, various
investigators reported RFR-induced decreases and/or increases
in heart rate, depending on average power densities. Decreases
in heart rate were reported for the lower range of power
densities used. The lowest SAR at which heart rate decreases were
observed in the isolated turtle heart was 1.5 W/kg. Some recent
work showed no RFR-induced changes in beat rate or contractile
force in isolated atria of rat hearts exposed to 2.45 GHz RFR at
2 or 10 W/kg.
   SAR-dependent changes in heart-beat rate in intact animals 
were also reported. The results indicate the existence of a
threshold between 4.5 and 6.5 W/kg, many orders of magnitude
higher than could occur outside the fence of a GWEN RN.
   Thus, in general, it is very improbable that physiological or
biochemical effects would occur from exposure to RFR from GWEN
transmitters at the levels that would be experienced outside the
fenced area of an RN.
   _Conclusion_. Most U.S. experiments with animals that yielded
recognizable and repeatable effects of exposure to RFR were
performed at whole-body average SARs of more than about 1 watt
per kilogram (W/kg). Such effects are thermal, in the sense that
the RFR energy is absorbed by the organism as widely distributed
heat that increases the whole-body temperature, or as internally
localized heat that is biologically significant even when
natural heat-exchange and thermoregulatory mechanisms are
functioning. The existence of threshold incident average power
densities has been experimentally demonstrated for some effects
and postulated for others. Exposure to RFR at average power
densities exceeding the threshold for a specific effect for a
few minutes to a few hours (depending on the value) can cause
irreversible tissue alterations. The heat produced by
indefinitely long or chronic exposures at power densities well
below the threshold is not accumulated because its rate of
production is readily compensated for by either heat-exchange
processes, thermoregulation, or both. Most investigations
involving chronic exposures of mammals yielded either no
effects or reversible, noncumulative behavioral or physiological
effects for average power densities exceeding whole-body SARs
of 1 W/kg. In the few cases in which irreversible adverse
effects of exposure were found, these effects were absent for
whole-body SARs below 1 W/kg. Whole-body SARs resulting from
exposure to RFR at a GWEN RN would be below 0.0000001 W/kg
outside of the 4-foot circular fence.
