The New Killing Fields: Electromagnetic Weapons
Ionizing and Non-ionizing Radiation
Radiation can be broadly
broken into two groupings: ionizing and non-ionizing. Ionizing
means that there is enough energy in the radiation
to alter the chemical structure of matter
upon its absorption by knocking off electrically
charged particles (ions). Non-ionizing
means that there is not enough energy in the radiation
to create ions. Instead, the energy
is usually absorbed as heat. RFR is a form of non-ionizing
radiation.
Because of their extremely
high frequencies and energies, X-rays and gamma rays are
electromagnetic types of "ionizing" radiation,
as are many types of high-energy,
high-velocity sub- atomic particles that result
from nuclear processes. When ionizing
radiation interacts with living structures, it
can cause severe damage. The chemical bonds
of molecules struck by high energy particles can
be broken, causing parts of the
molecules to be split off, often as reactive charged
particles (ions). These ions can
promote additional chemical and physical reactions.
If the absorbing molecules are DNA or
other genetic materials, cellular metabolism can
be interfered with and the cell's ability to
reproduce itself can be destroyed or caused to
malfunction (the latter sometimes leading
to cancers). (Barrett, see references.)
Electromagnetic waves
of lower frequency levels and energies, such RFR and EMFs
associated with radio systems, do not cause ionization
and consequently are referred to
as "non-ionizing" radiation. If absorbed
at all, this type of energy is absorbed as heat.
Unless generated at extremely high power densities
and at just the right resonance
frequencies so as to produce large amounts of heat
resulting in actual burns, the frequency
and resulting energy levels of non-ionizing radiation
are almost always too low to affect
biological materials. Non-ionizing radiation is
not known to damage DNA as can ionizing
radiation and generally has not been shown to cause
irreversible changes that can
accumulate over time (Yost, see references).
There is one potential
problem, however. Sometimes in a complex organic molecule short,
linear groups of atoms extend off of a main chain
or body of the complex. It has been
shown that at the right frequencies, these extensions
can be excited by strong,
non-ionizing energy so as to cause frequency resonance
to occur. The extension can then
vibrate and on occasion break off, altering the
structure of the molecule. This is the only
other known interaction between non-ionizing radiation
and biological structures. It is
considered to be a rare phenomenon, as the frequency
of the radiation must exactly match
the natural resonance of the molecule and the power
density must be very high. (Barrett,
see references.)
Why the Concern?
Most scientists maintain
that RFR and lower frequency EMFs such as those associated
with wireless communications systems generally
do not produce adverse health effects in
humans because they are non-ionizing in nature
and normal exposures are controlled so
as not to result in thermal effects. Other researchers,
however, note the possible molecular
resonance problem described above and propose that
continuous low-level exposures or
exposures in combination with other chemicals may
cause health problems that are not
immediately evident. These researchers suggest
that extra care should be taken until more
is known.
The media continue to
report the work of these researchers and the public exhibits a sharp
interest in the debate between the two sides. Some
members of the public believe that
even the remotest possibility of a health hazard
constitutes grounds for forming public
policy and regulations for facilities using radiofrequency
radiation and generating
electromagnetic fields. Consequently, there is
often keen public interest in proposals for
new wireless cell sites and facilities.
ANSI, NCRP, and IRPA Radiation Protection Guidelines
"Both private organizations
and government agencies have proposed guidelines that limit
exposure to nonionizing radiation. These standards
can be divided into broad categories:
emission standards, which set limits on the incidental
(nonpurposeful) radiation emanating
from a device; and exposure standards, which set
limits on the radiation power density to
which a person may be exposed. Emission standards
limit unwanted leakage from devices
such as microwave ovens that should contain the
radiation inside the device or that have
shielding to protect operators and others from
exposure during normal operation. Exposure
standards limit exposure of persons to radiation
present in the environment, for example
from a radio transmitter" (Yost, see references).
There is no official,
mandatory federal standard for radiation exposure protection in the
United States. The official guideline for facilities
regulated by the Federal Communications
Commission (FCC) is currently the 1982 American
National Standards Institute (ANSI)
guideline. The 1982 ANSI guidelines recommend exposure
limits covering RFR from 300
kHz (kilohertz) to 100 GHz (gigahertz). The guidelines
recognize that the human body
absorbs radiofrequency energy at some frequencies
more readily than at others. The most
restrictive limits are in the frequency range of
30-300 MHz. However, the wireless
communications systems discussed in this paper
operate in the frequency range of 800 to
2200 MHz -- frequencies outside of the most sensitive
range.
ANSI has adopted C95.1-1992,
a revision of the 1982 standard, and the FCC has proposed
its adoption. The new standard "contains a
number of significant differences from
guidelines and recommendations issued by ANSI in
1982. In many respects, the 1992
guidelines are more restrictive in the amount of
environmental RF exposure permitted, and
they also extend the frequency range under consideration
to cover frequencies from 3 kHz
to 300 GHz. The new 1992 guidelines specify two
sets of exposure recommendations, one
for 'controlled environments' (usually involving
workers) and another for 'uncontrolled
environments' (usually involving the general public).
(FCC 93-142).
For controlled environments,
the 1992 ANSI/IEEE standards recommend maximum power
density levels calculated by dividing frequency
by 300 (f/300). For example, for a cellular
frequency of 888 MHz, the standard would be calculated
by dividing 888 by 300, yielding
an exposure level of 2.96 mW/cm2 (milliwatts per
square centimeter). For uncontrolled
environments, the revised standards recommend maximum
power density levels calculated
by dividing frequency by 1500 (f/1500). As a result,
for the same cellular frequency of 888
MHz, the exposure standard for the uncontrolled
environment would be 0.592 mW/cm2
(888/1500). Thus, for both controlled and uncontrolled
environments, the ANSI/IEEE
exposure standards for wireless communications
are dependent upon the technologies
frequencies.
In addition to the ANSI
standard, there are two other widely discussed public exposure
standards: that of the National Council on Radiation
Protection (NCRP) and that of the
International Radiation Protection Association
(IRPA). Because the NCRP standards cover
the 1500 MHz to 1011 MHz frequency range and the
IRPA standards cover the 2,000 MHz
to 1011 MHz frequency range, these two exposure
standards apply only to the upper
portions of the PCS frequency range. They do not
apply to the cellular or ESMR
technologies, whose frequency ranges lie between
800 and 900 MHz.
The NCRP is a non-profit
corporation chartered by the United States Congress to, among
other things, develop information and recommendations
concerning radiation protection.
The guidelines issued by the NCRP specify a level
of 1 mW/cm2 (milliwatt per square
centimeter) for the exposure of the general public
in the frequency range listed above.
The IRPA is a non-governmental
international organization representing most of the
national radiation protection societies in the
world. These recommendations form part of
the World Health Organization (WHO) United Nations
Environmental Programme (UNEP).
IRPA guidelines for public exposure also recommend
1 mW/cm2 for the frequency range
listed above. It should be noted that both the
NCRP and IRPA exposure standards are
more restrictive than the revised ANSI standards
for PCS frequencies above 1500 MHz in
uncontrolled environments and for all PCS frequencies
in controlled environments.
Some states, including
Massachusetts, New Jersey, Oregon, and Washington, as well as
some local jurisdictions have adopted their own
radiation guidelines.
Radiation Levels
The levels of RFR to which
the public is routinely exposed are far below the levels
necessary to pose a health risk. A 1989 report
by the Office of Engineering and
Technology stated that the U.S. Environmental Protection
Agency estimates that in seven
metropolitan areas studied across the United States,
98 to 99 percent of the population is
exposed to less than 0.001 mW/cm2 of radiation.
The standards listed above are
considerably more restrictive than the exposure
levels that the majority of the public
experiences.
Additionally, the 1982
ANSI guidelines for radiation exposure indicate that devices
operating on less than seven watts of power at
frequencies less than 1,000 MHz will not
cause immediate thermal effects. Cellular mobile
phones operate between 0.6 and three
watts of power at frequencies between 800 and 900
MHz, ESMR mobile communicators
operate between 0.5 and 1.5 watts of power in the
800 MHz frequency band, and PCS
mobile communicators are anticipated to operate
on no more than 1 watt of power at
frequencies between 1,850 and 2,200 MHz, all falling
well below the seven watt threshold.
Typical cell sites, including
monopoles, roof-mounted antenna sites, and building-mounted
antenna sites, emit a maximum of 3,000 watts of
effective radiated power (ERP) (the power
supplied to an antenna multiplied by the relative
gain of the antenna in a given direction). In
comparison, radio broadcasting towers emit roughly
100,000 watts ERP, and television
broadcasting towers emit approximately 5,000,000
watts ERP. The radiation emitted from
these broadcasting sources decreases according
to the inverse square principle. As a
result, exposure to radiation decreases as distance
from broadcasting sources increases.
Ongoing and Future Research
Although many studies
have been conducted examining the effects of RFR and EMFs on
animals and humans, scientists have been unable
to reach consensus on the results for
various reasons, including: difficulty in interpreting
the extrapolation of studies performed
on animals and cells to humans; difficulty in explaining
the effects of natural influences,
such as the earth's magnetic field; difficulty
in controlling crucial variables in the study,
such as the amount of energy absorbed by test organisms;
difficulty in replicating and
generalizing results obtained at specific power
levels, frequencies, and modulation
patterns, to other situations; difficulty in distinguishing
between slight normal human
changes and subject variations; and difficulty
in agreeing on the results and methodologies
of epidemiological studies.
While some studies suggest
that long-term exposure to some forms of RFR may cause
adverse health effects in humans, many other studies
do not. According to a report
published in 1994 by the United States General
Accounting Office, both the Food and Drug
Administration (FDA) and the Environmental Protection
Agency (EPA) agree that the
information from the most current studies is insufficient
to determine whether the risks are
substantive, if present at all.
In fact, some cities,
such as the City of San Diego, have addressed this issue by
distinguishing between actual and perceived health
hazards when performing CEQA
(California Environmental Quality Act) review.
The city recognizes that the public's fear of
the unknown sometimes causes "perceived health
hazards." Since studies have been
found inconclusive in relation to the thresholds
established by the ANSI standards, the city
does not identify EMF impacts on human health as
significant. Nonetheless, the policy of
the Environmental Analysis Section (EAS) of the
Development and Environmental Planning
(DEP) section of the Development Services Department
(DSD) is to disclose the presence
of EMF sources, and advise "prudent avoidance,"
where possible. An example of prudent
avoidance would be to place power lines or other
sources of radiation in places of
low-intensity human uses, such as parking lots.
Concurrently, the City of Poway has
suggested that required buffer distances would
be helpful in separating such facilities from
areas where people tend to cluster, such as schools,
residences, parks, and day care
centers.
RFR Research Related to Wireless Communications
In 1991, the California
Public Utilities Commission (CPUC) opened Investigation 91-01-012
to consider whether the CPUC should adopt a role
to mitigate potential health effects, if
any, of EMFs created by electric utility power
lines and cellular facilities. Consensus was
reached that EMF issues involving electric utilities
and cellular utilities should be
addressed separately. A cellular steering committee
composed of five individuals was
established with one individual representing each
of the following agencies: the CPUC's
Commission Advisory and Compliance Division (CACD),
the Division of Ratepayer
Advocates (DRA), the California Department of Health
Services (DHS), the Cellular Carriers
Association of California (CCAC), and the "Citizens
Concerned About Telecommunications
EMF." In July 1993, the steering committee
held an informational workshop addressing
three issues: levels of cellular utilities' EMF
and RFR impacts, issues for further
consideration, and interim safety measures.
In December 1994, the
CACD released a summary of the workshop. The report concluded
that although little is known about potential health
hazards related to EMF and RFR
exposure levels, cellular power densities have
been found to be consistently below present
exposure standards. In the absence of scientific
evidence linking cellular exposure levels to
human health risks, the steering committee decided
not to adopt a specific numeric set of
EMF and RFR exposure standards associated with
cellular facilities. However, recognizing
that future scientific research may provide more
definitive information, the CACD adopted
the responsibility to serve as a clearinghouse
of EMF and RFR research and to hold
periodic workshops informing interested parties
of new findings.
On November 8, 1995, the
CPUC released Decision 95-11-017. The decision (1) adopts the
CACD's workshop report (except for a proposed interim
measure requiring cellular utilities
to consider alternative cell site locations and
restrict access to their cell sites through
warning signs or physical barriers); (2) approves
the designation of the CACD to hold
workshops as additional health information becomes
available and requires that the
workshop results be reported to the CPUC through
the resolution process; and (3) closes
Investigation 91-01-012.
In November of 1994, the
United States General Accounting Office published a report addressing
the status of scientific knowledge on the effects
of RFR caused by cellular telephones. The report
found that no long-term studies on low levels of
radiation from cellular phones have been
completed, and that the research conducted on other
sources of low-level RFR are inconclusive.
The report further determined that both epidemiological
and laboratory studies are needed to
ascertain whether portable cellular phones produce
adverse health effects. Two such studies are
under way:
1. In 1991, Motorola,
Inc., contracted with a prominent U.S. research company to study the
effects of analog and digital signals from cellular
telephones on animals and cells. Results are
expected to be released in late 1995 or early 1996.
2. In 1993, due to public
anxiety that portable cellular phones cause adverse health effects, the
Cellular Telephone Industry Association (CTIA)
allocated $15 to $25 million to study the safety of
cellular phones for three to five years, including
the effects of analog and digital radiation at
cellular and PCS frequencies. The CTIA and other
industry representatives established a Science
Advisory Group on Cellular Telephone Safety to
perform this research through epidemiological
studies, cell cultures, animal testing, and genetic
research. The research will be submitted to a
scientific peer review coordinated through the
Harvard University Center for Risk Analysis. This
research will be open for federal participation
in order to provide further objectivity.
The federal government
also is undertaking research that focuses specifically on cellular
telephone safety issues. The National Cancer Institute
has begun an epidemiological study of
people with brain cancer to ascertain whether there
is a statistical relationship between cancer
and the use of cellular telephones. It is anticipated
that this study will be completed between
1998 and 1999.
The research conducted
up to the present is considered inconclusive, but important questions
have been raised about the possible relationship
between health complications and the exposure
to radiofrequency radiation and electromagnetic
fields. The studies cited above, in combination
with other human and laboratory studies, could
provide the kind of comprehensive research
needed to determine the safety of wireless communications
devices.
RFR and EMF Information Sources
In January of 1995, the
Department of Energy released a booklet entitled Questions and
Answers about EMFs, published by the department's
Research and Public Information
Dissemination (RAPID) program. The RAPID program
was established in 1992 as a five
year, $65,000,000 program to study if exposure
to EMFs causes adverse health effects. To
order free copies, call 1 (800) 363-2383, or call
Alicia Hillery for bulk orders at (202)
512-1708.
For additional information
on EMFs, Planning Advisory Service Report #435,
Electromagnetic Fields and Land-Use Controls, by
David Bergman, Louis Slesin, and
Matthew Connelly (Chicago: American Planning Association,
1991) can be ordered through
the American Planning Association's Planners Bookstore,
122 S. Michigan Ave., Suite
1600, Chicago, IL 60603; (312) 431-9100. Additionally,
the ANSI Standards, also known as
IEEE Standard for Safety Levels with Respect to
Human Exposure to Radio Frequency
Electromagnetic Fields, 3 kHz to 300 GHz, 1992
(ANSI/IEEE c.95.1-1992), and
Recommended Practice for the Measurement of Potentially
Hazardous Electromagnetic
Fields - RF and Microwave (ANSI/IEEE C95.3-1992)
are available through the American
National Standards Institute, 11 W. 42nd St., New
York, NY 10036; (212) 642-4900.
ABBREVIATIONS OF TERMS
A/m
Amperes per meter
ANSI
American National Standards Institute
BTA
Basic Trading Area
CCAC
Cellular Carriers Association of California
CDMA
Code Division Multiple Access
CDPD
Cellular Digital Packet Data
CEQA
California Environmental Quality Act
CFR
Code of Federal Regulations
CGSA
Cellular Geographical Service Area
CPUC
California Public Utilities Commission
CTIA
Cellular Telecommunications Industry Association
DEP
Development and Environmental Planning
DHS
Department of Health Sciences
DRA
Division of Ratepayer Advocates
DSD
Development Services Department
EAS
Environmental Analysis Section
EIR
Environmental Impacts Report
ELF
Extremely Low Frequency
EMF
Electromagnetic Field
EPA
Environmental Protection Agency
ESMR
Enhanced Specialized Mobile Radio
FCC
Federal Communications Commission
FDA
Food and Drug Administration
GHz
Gigahertz
G.O.159 (A)
General Order 159 (A)
IEEE
Institute of Electrical and Electronic Engineers
kHz
Kilohertz
LCP
Local Coastal Plan
MHz
Megahertz
MSO
Main Switching Office
MTA
Metropolitan Trading Area
mW/cm2
Milliwatt per square centimeter
PCS
Personal Communications Services
RFR
Radio Frequency Radiation
RSA
Rural Statistical Area
SMR
Specialized Mobile Radio
SMSA
Standard Metropolitan Statistical Area
TDMA
Time Division Multiple Access
V/m
Volts per meter
WTB
Wireless Telecommunications Bureau
GLOSSARY
Analog Technology (see
Digital Technology)
Analog technology replicates and amplifies voice
messages as they are carried from the
transmitting antenna to the receiving antenna.
Traditionally, cellular phone systems have
used analog transmission signals.
Antenna
A device used in communications which transmits
or receives radio signals.
Band
A clearly defined range of radiofrequencies dedicated
to a particular purpose.
California Public Utilities
Commission (CPUC)
Governmental agency which regulates the terms and
conditions of public utilities in the
State of California. Of the three wireless communications
services discussed in the Issues
Paper, the CPUC presently regulates only cellular
service providers.
Channel
A segment of a frequency band. Also referred to
simply as ìfrequency.î
Co-location
Locating wireless communications equipment from
more than one provider on a single site.
Common Carrier
A public radio service in which a single licensee
provides one-way or two-way service to
multiple users.
Communications Facility
A land use facility supporting antennas and microwave
dishes that sends and/or receives
radiofrequency signals. Communications facilities
include structures or towers, and
accessory buildings.
Digital Technology
Digital technology converts voice and data messages
into digits that represent sound
intensities at specific points of time and data
content. ESMR and PCS service providers
employ digital technology, and cellular providers
are rapidly converting to digital as well.
Dish Antenna
A dish-like antenna used to link communications
sites together by wireless transmission
of voice or data. Also called microwave antenna
or microwave dish antenna.
Effective Radiated Power
(ERP)
The power supplied to an antenna multiplied by
the relative gain of the antenna in a given
direction.
Electromagnetic Field
(EMF)
The local electric and magnetic fields that envelop
the surrounding space. The most
ubiquitous source of EMFs is from the movement
and consumption of electric power, such
as with transmission lines, household appliances
and lighting.
Federal Communications
Commission (FCC)
The federal agency responsible for licensing and
regulating wireless communications
providers. The FCC has primary regulatory control
over communications providers through
its powers to control interstate commerce and to
provide a comprehensive national system
in accordance with the Federal Communications Act.
Frequency
The number of cycles made by electromagnetic radiation
in one second, usually
expressed in units of hertz (Hz).
Hertz
A unit for expressing frequency which is the number
of times a wave-like radio signal
changes from maximum positive to maximum negative
charge per second. 1 Hz = 1 cycle
per second. 1 kilohertz (kHz) = 1,000 Hz; 1 megahertz
(MHz) = 1,000 kHz or 1,000,000
Hz; 1 gigahertz (GHz) = 1,000 MHz or 1 million
kHz or 1 billion Hz.
Interference
Disturbances to reception caused by radiofrequency
waves or other electric fields.
Microwave
Electromagnetic radiation frequencies from 3 GHz
to 300 GHz; highly directional when
used for radiofrequency transmissions. Uses relatively
low transmitter power levels when
compared to other forms of transmission.
Monopole
A structure composed of a single spire used to
support communications equipment.
Non-ionizing Electromagnetic
Radiation
Electromagnetic waves of low frequency, long wavelength,
and low photon energy unable to
cause ionization (i.e., to remove an electron from
an atom).
Panel Antenna
An antenna or array of antennas designed to concentrate
a radio signal in a particular area.
Panel antennae are typically flat, rectangular
devices approximately six square feet in size.
Also called directional antennae.
Power Density
The magnitude of the electromagnetic energy flux
density at a point in space, in power per
unit of area (measured in milliwatts per square
centimeter or mW/cm2).
Radio
A generic term referring to communication of impulses,
sounds, and pictures through
space by means of electromagnetic waves.
Radiofrequency Radiation
(RFR)
Electromagnetic radiation in the portion of the
spectrum from 3 kHz (kilohertz) to 300 GHz
(gigahertz).
Stealth Facility
Any communications facility which is designed to
blend into the surrounding environment.
Examples of stealth facilities may include architecturally
screened roof-mounted antennas,
building-mounted antennas painted to match the
existing structure, antennas integrated
into architectural elements, and antenna structures
designed to look like light poles. Also
called concealed antennas.
Wavelength
The distance between points of corresponding phases
of a periodic wave of two constant
cycles. Wavelength = wave velocity/frequency.
Whip Antenna
An antenna that transmits signals in 360 degrees.
Whip antennae are typically cylindrical
in shape and are less than 6 inches in diameter
and measure up to 18 feet in height. Also
called omnidirectional, stick, or pipe antennas.