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RE: [many times over] radiation is radiation
Group,
Oh, how I have tried to stay out of this but:
Michael Kent Wrote,
"As has been pointed out numerous times, cancer rates in Denver, Co are not
higher than the national average. This is true, even though they live in an
area where background radiation is twice as high AND they have Rocky Flats
next door (lot's and lot's of DEADLY Plutonium, and other nasty stuff)."
NCRP 94, Exposure of the Population of the United States and Canada from
Natural Background Radiation", Sep 92, Chapter 8, "Unusual Exposures", 8.1.1
Denver, CO., "...The previous NCRP report on natural activity noted that
both the cosmic ray and terrestrial exposures were somewhat higher there and
that the total dose equivalent is about 50% higher than the mean for the
U.S."
It should be noted that NCRP lists 5 components to background; cosmic,
cosmogenic, terrestrial, inhaled, and in the body. Cosmic from the sun's
fusion; cosmogenic from reactions of cosmic rays with atmosphere producing
C-14 [carbon dating]; & H-3 and others; terrestrial, natural uranium and
thorium decay sequences + K-40 & Rb-87; inhaled = decay products of radon
[in turn a decay product of radium part of the natural uranium decay
chains]. The in tissue component is complicated as it includes isotopes
that are formed cosmogenically, from terrestrial sources and Po-210 from
cigarette smoke and fallout.
Note First that the average total dose equivalent rate is 300 mrem/y and
next that inhaled is about 200 mrem/y and in tissue about 40 mrem/y. The
total EXTERNAL BACKGROUND rate [which is what I always thought of, when
background radiation was mentioned] is about 60 mrem/y for the country [&
Canada] as a whole. If Denver is 50% higher for the total that would be 150
mrem additional due to cosmic & terrestrial sources and so our external
background rate would be about 210 mrem/y or about 3.5 times higher than the
US & Canada's average external background.
I guess the moral of the story is when you talk background, be careful and
carefully define your terms. Please all feel free to use the higher figure
when talking about Colorado and don't forget the deadly plutonium at Rocky
Flats.
Any opinions expressed are mine alone and do not necessarily represent those
of the Denver VA Medical Center, The Department of Veterans Affairs, or the
U.S. Government.
Peter G. Vernig
Radiation Safety Officer, VA Medical Center, 1055 Clermont St. Denver, CO
80220, ATTN; RSO MS 115
303-399-8020 ext. 2447, peter.vernig@med.va.gov [alternate
vernig.peter@forum.va.gov] Fax 303-393-5026 [8 - 4:30 MT service] Alternate
Fax 303-377-5686
"...whatever is true, whatever is noble, whatever is right,, whatever is
pure, whatever is lovely, whatever is admirable, if anything is found to be
excellent or praiseworthy, let your mind dwell on these things." Paul
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