misc

["Ted Rockwell" <tedrock@cpcug.org>]

Harry Hinks:

To repond to three questions you posed:

1. You rightly noted that iodine would not follow the noble gases during the
release at TMI.  One of the major differences between water-moderated
reactors and the Chernobyl type is the presence of large amounts of water,
even after a meltdown.  In that situation, iodine largely disolves in the
water, and most of what's in the air plates out on the colder metal surfaces
in containment.  If I remember correctly, this reduced the iodine by a
factor of 10^5, whereas the noble gases had almost no reduction.

2. Fritz Seiler's point about radon is that Cohen measured real people
living in real homes and going about their real lives, and he used radon
measurements in real homes.  Thus, when LNT advocates dismiss these data and
use miners breathing diesel fumes, silica dust, uranium oxide, etc. they are
not measuring the population of interest.  Seiler's point is that to the
degree that the data on miners disagree with Cohen's, the burden is on the
former to show where confounding errors have caused a difference, because
Cohen's people are the ones on whom the regulations will be applied.
Whatever confounding factors exist between the two are already protecting
the people :-) Cohen's critics raised a number of generic questions, but
none have been able to show that any of these could actually reverse Cohen's
dramatic and consistent curves.  Cohen, as I understand it, is disagreeing
with Seiler only in saying that he has not proved a pure relationship
between radon levels and lung cancer, only a practical relationship between
people living in homes with radon and the resulting risk of cancer.  Be that
as it may, it's certainly the best data available and agrees with everything
else we know about radiation effects.

BEIR-VI, the LNT bible on radon, relegates Cohen's many papers to Appendix
G, which concludes (page G-5) that each of the potential confounders was
addressed, and that the strong negative association he found "could not be
explained by confounding.  Cohen proposes that the negative association
implies failure of the linear non-threshold theory for carcinogenesis from
inhaled radon decay products."  There is no further discussion of this
matter, and the report, in its body, refers only generically to such
studies, concluding  "The studies have not produced a definite answer."
After estimating "15,400 to 21,800 deaths attributed to radon in combination
with smoking" the report concludes that 95% were smokers, and "Most of the
radon-related deaths among smokers would not have occurred if the victims
had not smoked."

That's all they could come up with, after 3 years and a great many of your
dollars and mine.

3. As for theory, a number of papers, notably by Pollycove and Feinendegen,
explain that for every DNA damaged by radiation, several million are damaged
by normal metabolism.  Radiation does cause more double breaks, but even a
generous allowance for this leaves the DNA done by radiation trivial.  Even
a lethal dose of radiation does not accomplish its lethality because of the
DNA damage.  Instead, high level radiation kills when it degrades the body's
protection mechanisms and they can no longer take care of damage by
metabolism.  Of course, at those high radiation levels, other types of
damage also occur.  But we have to get away from the physicist's view that
all nuclear damage can be calculated as a target cross-section problem.

As for subambient radiation data, this was studied and ORNL and ANL 50 years
ago.  To do it well required replacing normal potassium (which contains
radioactive K-40) with K-39 in the animal's food.  In the decreased
radiation field, "the cells looked normal, but they didn't function."  This
(hormesis) is a nearly universal phenomenon in biology.  "Nothing is poison,
but the dose makes it so" (Paracelsus, 1640) As toxicologists lowered
permissible levels of poisons such as selenium, chromium and the like, they
found themselves infringing on the Recommended Daily Allowance set by
nutritionists.

Since there really is no NLT THEORY, just an unsupported premise, it's hard
to see why anyone should be surprised that it isn't true.

Ted Rockwell

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