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Do Radio Towers Belong In
Your Neighborhood?
Smart Safe Hollow Air Tube
Cell Phone Radiation Protection
Radiation Protection Products
March 6, 2012
The town of Brighton has seventy-three radio towers so I
thought I’d find out more about the guidelines for safe
exposure and safe proximity to low-frequency radio waves or
electromagnetic fields (EMFs).
I asked Kenneth R. Foster, noted professor of bio-medical
engineering at the University of Pennsylvania recently about
the health and environmental impact of radio towers and the
low-frequency non-ionizing radiation they emit. Foster
teaches and writes extensively on the ethics of technology.
He is a former president of the Institute of Electrical and
Electronic Engineers’ (IEEE) Society of Social Implications
of Technology.
My questions stemmed from a review I’d read online published
in 1999 by the Royal Society of Canada which compiled and
assessed several studies. Foster discussed this review and
other studies to compare their findings. He spoke candidly
about the state of regulatory standards and the limitations
of testing.
There is only one known hazard to low-frequency non-ionizing
radiation according to Foster and that is “thermal heating”
or excessive heating of body tissue, which, he says, “…is
not a concern for the low levels of radiation that are
emitted from a cell tower base station (site of multiple
radio towers).” Close, occupational exposure can raise body
temperature enough to heat up cells.
Some of the non-thermal health concerns reviewed by the 1999
Royal Society summary can raise eyebrows. Included are DNA
damage, chromosomal changes, increased cell proliferation,
changes in calcium and melatonin levels, cell membrane
effects and greater permeability of the Blood Brain Barrier.
The Canadian report concluded, “Because of the low field
strengths associated with public exposure to RF fields from
wireless telecommunications base station transmitters,
neither biological nor adverse health effects are likely to
occur.”
While current proof of non-thermal health hazards from a
base station is minimal, I was surprised to learn from
Foster that limited studies have been done on humans to
date, and fewer on children. Studies have been conducted in
the lab on animals. Many researchers extrapolate from that
research alone, that constant low-frequency radiation in a
residential neighborhood is safe for its residents.
“Few studies have investigated general health effects in
individuals exposed to RF fields from base stations. This is
because of the difficulty in distinguishing possible health
effects from the very low signals emitted by base stations
from other higher strength RF signals in the environment.
Most studies have focused on the RF exposures of mobile
phone users,” says Foster.
Apparently, we have so much daily exposure to cell phone
radiation, home electronics and medical testing (MRI’s) that
it would be too difficult to isolate the exposure from a
base station, say, next door to your home, or adjacent to a
school. And exposure is cumulative.
So if you live in the center of several base stations, for
example, the exposure is compounded. Luckily, according to
Foster, low frequency non-ionizing radiation from radio
towers falls off quickly. Cell towers are fully digital with
signals that are pulse-modulated. I learned that the
strength of an RF field is greatest at its source and
diminishes quickly with distance.
I asked Foster about who sets safety guidelines for
exposure. The FCC relies upon the Institute of Electrical
and Electronic Engineers (IEEE), an independent scientific
organization to develop guidelines for limits on exposure.
The National Council on Radiation and Measurements also
provides data to set guidelines for exposure. The FCC then
regulates emissions to meet these standards.
Broadcast towers, like the base station at Pinnacle Hill,
operate over a range of RF frequencies typically at far
higher power levels than cell tower base stations. Exposure
levels may be more or less depending upon the distance of
the antenna from an individual, the height of the antenna
and other factors.
High frequency fields, part of the electromagnetic spectrum
between low frequency and the optical part of the spectrum
is what’s used for broadcasting and telecommunications. They
provide more exposure to non-ionizing radiation than cell
phone towers but are still strictly regulated by FCC
guidelines.
William P. Johnson, professor of Electrical Engineering at
Rochester Institute of Technology, says that broadcast
towers like those at Pinnacle Hill “throw lots of power in
one direction, in order to transmit a signal.”
A 2009 review by the International Commission of
Non-Ionizing Radiation Protection (ICNIRP) assessed higher
frequency non-ionizing radiation, mostly from exposures
between 100kHz-300kHz–lower exposure than an average cell
phone–but within the range of broadcast towers.
Studies within this review found a change in the formation
and arrangement of cells at 100MHz exposure. Polar molecules
such as water and other cellular components translated and
rotated in response to electrical fields. “Cells would
rearrange and form chains along the direction of the field.”
Also noted were acoustic effects. The ICNIRP Review explains
that a rapid rise in temperature launches an acoustic wave
of pressure that travels to the cochlea (structure in the
ear), detected by hair cells (inside the ear) and relayed to
the central auditory system for perception. A single
microwave pulse can be perceived as an acoustic click or
knocking sounds, and a train of microwave pulses to the head
can be sensed as a buzz or an audible tune.
The ICNIRP Review also cites changes in cell-signaling,
among other changes, as a result of exposure at 900 MHz in
mice who showed a two-fold increase in Lymphoma at this
level. Also at 900 Mhz, a significant decrease in Serum TSH,
T3 and T4–thyroid indicators.
When asked about the possibility of cancer clusters around
broadcast towers, Foster confides, the exposure assessment
is “very murky around broadcast towers due to the number of
variables involved. Studies on cancer clusters around these
sites have been inconclusive.”
By comparison, Foster adds that, “The exposure level for
someone holding a cell phone to their ear is much higher
than the radiation they would receive from a cell tower
because of the phone’s proximity to the body.”
The World Health Organization (WHO) cites no hazards from
low-frequency non-ionizing exposure but Foster warns, “No
known hazards have been identified but we don’t know
everything and can’t.” He remains skeptical that any health
hazards will be demonstrated from low exposure levels of RF
energy within the current guidelines but admits that human
knowledge is necessarily incomplete and no one can predict
what may be learned in the future.
The 2009 ICNIRP Review concluded,”Results of epidemiological
studies to date give no consistent or convincing evidence of
a causal relation between radio frequency exposure and any
adverse health effect. On the other hand, these studies have
too many deficiencies to rule out an association. …Although
the likelihood is low that fields emanating from base
stations would create a health hazard, because of their
weakness, the possibility is nevertheless a concern for many
people. To date, no acceptable study on any outcome has been
published on this. On the one hand, results from valid
studies would be of value in relation to a social concern;
on the other hand, it would be difficult to design and
conduct a valid study. …”
Scientific evidence on the distribution of cancer in the
population can be obtained through carefully planned and
executed epidemiological studies. Foster tells me, that over
the past 15 years, studies examining a potential
relationship between RF transmitters and cancer have been
published. “These studies have not provided evidence that RF
exposure from transmitters increases the risk of cancer.
Likewise, long-term animal studies have not established an
increased risk of cancer from exposure to RF fields even at
levels that are much higher than produced by base stations
and wireless networks.”
Foster says the possible health effects of RF energy is a
subject of intense investigation and exposure limits are
constantly being re-evaluated. He also points out that more
rigorous epidemiology studies involving human exposure to RF
energy are in the works, including those related to the use
of cell phones by children.
With so much that is unknown, and with our exposures
increasing every day, from cell phone use and a need for
more base sites to accommodate a growing population of cell
phone users, isn’t it time to review current guidelines,
begin more rigorous testing, and, at the very least, admit
that we simply don’t know the long-term effects of the
levels of exposure we are getting?
If cancer clusters appear in neighborhoods close to
broadcast towers, or in residents in close proximity to
radio and cell towers, rather than assuming there is no
connection, shouldn’t we be proactive and look further?
I am not convinced from talking to Kenneth Foster and others
that all the facts are in on exposure to low-frequency,
non-ionizing radiation, nor am I convinced that the
guidelines set for exposure to these electromagnetic fields
will safely take us into the future.
We need to explore the genotoxic potential of combining RF
exposure with chemical mutagens and ionizing radiation. It’s
time to consider the tipping point of prolonged and combined
exposures to all forms of radiation.
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