Subject: (Curry) LAN safety vis... absorption by the brain......
Date: Wed, 9 Jun 1999 010452 -0500 (CDT)
From: "Roy L. Beavers" <rbeavers@llion.org>
To: emfguru <rbeavers@llion.org>
--------------------------------------------------
........I'm sure that Bill would appreciate some commentary on this from
those scientists doing similar work...... (Dr. Ohm Gandhi???)
Roy Beavers (EMFguru)......
rbeavers@llion.org.......
.....It is better to light a single candle than to curse the darkness.....
EMF-L web-site can be found at:
EMF-L archives can be found at:
..................PEOPLE ARE MORE IMPORTANT THAN PROFITS..................
---------- Forwarded message ----------
Date: Tue, 08 Jun 1999 23:22:34 -0500
From: "Bill P. Curry"
To: "Roy L. Beavers"
Subject: Re: (Noonan) An awareness of the Blue World.....
Roy and Susan,
I don't like the precedent of putting low towers with communications gear on
school sites. To see whether the proposed radiation levels are likely to be
harmful, you need to know the radiation frequency and the effective radiated
power from each antenna, as well as the distances the antennas will be from
where the children gather. The radiation density at the location where the
children will be can be computed from the power emitted, the gain of the
antennas (in decibels), the direction of the most intense radiation (i.e., the
direction of maximum gain) from the antennas. The formulae in the FCC
document OET-65 can be used to make the radiation density estimates. I have
set up these formulae in my computer and give you a quick answer, if you will
provide me with the requested information.
I think this project is an insidious way for the wireless system protagonists
to inculcate thamselves into routine activities at schools. Some providers go
so far as to buy equipment for schools that participate in their wireless LAN programs.
One company that works in this field int he US is RadioLAN. The primary
concern I have about their system is the fact that the frequency of the system
is 2.5 GHz (microwave oven frequency). Other proposed systems will probably
be at even higher frequency. The consequence of being at such frequencies is
the fact that human tissue (especially brain tissue) absorptivity of microwave
radiation increases with frequency in this region of the spectrum. In fact at
2 GHz, the absorptivity is about 5 times higher than it is at a few hundred
MHz (UHF TV frequencies). Something else that concerns me is the possibility
that the microwaves at these high frequencies may have harmonics that overlap
the region in which DNA molecules can absorb mirowave radiation. Also, Henry
Lai of the University of Washington has studied the effect of 2.5 GHz
radiation on DNA molecules by use of what biochemists call an Assay Technique.
He shows that the radiation can disrupt DNA molecules almost as effectively
as x-rays can. You can see dramatic slides of this on the web site
www.electric-words.com, which is the site of an Australian Journalist with a
medical background. There are published calculations from people at Purdue
University (not yet confirmed by experiment) that indicate the DNA microwave
absorption spectrum extends from about 10 GHz to 100 GHz. In addition to my
concern about harmonics of 2.5 GHz radiation falling within this spectral
region, there are some proposed systems that will operate around 18 GHz. I
don't think this is wise.
Finally, if the brain were uniform and spherical, I could tell you for sure
that the wavelength (inside the brain tissue) of 2.5 GHz radiation would be
small enough to cause resonances of the microwave radiation on the surface of
the brain - at least for the size of an adult brain (14 cm equivalent
spherical diameter). I am not sure whether a child's brain is large enough to
be susceptible to such resonances. The consequence of such resonances is to
cause two "hot spots" on opposite sides of the brain - one spot nearest the
region of incidence of the radiation on the head and the other spot precisely
opposite this region on the other side of the brain. In these spots, the
radiation intensity exceeds that which is incident on the head but outside of
the head. This means that (for a sphere with uniform dielectric and
absorptive properties) the spherical shape of the simulated "brain" would
focus the radiation into these two spots. The intensity of the radiation any
where outside of these spots would correspondingly be less than that incident
on the head. I have carried out calculations that show this result, but I
don't know whether such resonances would occur in reality when you take into
consideration the nonuniformity of the brain and the deviations of its shape
from spherical.
To sum all this up, I think it is a bad idea to install antenna towers for
wireless systems on school campuses. As long as the radition is restricted to
individual rooms, it is probably has too low intensity to be significant, but
radiation of sufficient power to be used in LAN systems between buildings will
probably have sufficient radiation power density to cause biological effects.
If you calculate the radiation density, you can look up the observed
biological effects at that readiation level on the web pages of WaveGuide at
www.wave-guide.org/ccwti/studies.html. If you want me to make the
calculations for you, I will be glad to do so gratis and will share the result
with the list (unless you say otherwise), if you can provide me with the data
I need for inputs to the calculation. specifically, I need the power put into
each channel of each antenna, the number of simultaneously active channels,
the number of antennas at any one location, the direction of these antennas
(with respect to where the children are) the gain of the antennas (if
possible, the manufacturer and model number of the antennas - so that I can
find out how large is the region of maximum gain), the height of the antennas
above the children, and the horizontal distance from the antennas to the
children. Let me know if you wish me to do these calculations.
Roy L. Beavers wrote:
>
> .......I'm sure this lady would appreciate some responses.....
>
> Roy Beavers (EMFguru)......
> rbeavers@llion.org.......
> .....It is better to light a single candle than to curse the darkness.....
> EMF-L web-site can be found at:
> EMF-L archives can be found at:
> ..................PEOPLE ARE MORE IMPORTANT THAN PROFITS..................
>
> >From gnoonan@telusplanet.net Tue Jun 8 18:48:42 1999
> Date: Tue, 08 Jun 1999 17:10:52 -0600
> From: Gavin Noonan
> To: rbeavers@llion.org
> Cc: rriedlin@uniserve.com
> Subject: [Fwd: Hans , further info and I think I need help]
>
> Dear Hans
>
> I just thought I'd write and let you know what is happening here in Red
> Deer Alberta. We as a community have rallied many community members in
> several areas of the city to oppose the installation of the
> communication towers proposed for the schools in our city. in total we
> are looking at the erection of 17 towers of 30 metres and under. The
> towers are to improve commuication between schools and on the computors
> in the schools. They are hoping to alleviate the expense of rent from
> one of the companies and extra expense incured with fibre optics.
>
> We, at least 20, attended a Municipal Planning Commission Meeting last
> week in which we were able to present our concerns along with the
> arguments for the proposed system from the school board. As a result
> the commission has recommended their decision be tabled and that the
> community and school boards hold some meetings. It sounds like we will
> have the provincial government as mediator. A planner or others from
> the environment branch will be apointed. The municipal planning
> commission realizes that this is a bigger issue and that policy will
> have to be developed for the future as community becomes more aware of
> the risk factors involving emf's.
>
> I am really happy that the school board kept highlighting the fact that
> there already is a lot of emf pollution out in the community already. He
> spoke of the taxi's, the radio and television and we were also informed of
> all the individual home owners that are now placing applications for
> personal towers. I have noticed these popping up all over almost
> overnight. They are not so tall, just a bit taller than trees in the
> vicinity. A scary thought though that every 2nd or 3rd house might be
> having these towers in their backyards. What kind of issues are a concern
> here??? I am yet to fing out the use for these. Are they a replacement
> for tv dishes or are they bigger and better for the computer and maybe
> more??
>
> Well, this is the story from Red Deer. Now I guess I need to gather up
> the ammunition and be prepared to recommend policy for our city and
> surounding community. i have heard rumours that perhaps we will provide
> the groundwork for a provincial policy.
>
> I need help and support! I am sure you and contacts have ideas for
> creating policy and ideas on what definitely needs to be given as
> information on which to base this recommendation of policy???? The info
> on the emf guru site is excellent but at this point I am not sure what
> to zero in on to make a clear, concise point and presentation. We sure
> can use some expertise here - ideas on policy Hans or who I should
> contact???
>
> Thanks Hans and all the others from emf guru, etc. Thanks for taking
> the time to read my message. I look forward to your response.
>
> In Red Deer, Susan Spyker-Noonan
> gnoonan@telusplanet.net
--
----
Bill P. Curry, Ph.D. |Physics is fun.
EMSciTek Consulting Co. |Trying to make a living!
22W101 McCarron Road, |Phone: (630) 858-9377
Glen Ellyn, IL 60137 |Fax: same, but require prior notice
Home page: http://www.EMSciTek.com
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----------------------------------------------------
Archive provided courtesy of WaveGuide, http://www.wave-guide.org
Reprinted with permission of Roy Beavers, http://www.feb.se/EMF-L/EMF-L.html