RE: Does Size Matter?

[Dick King <king@reasoning.com>]

radsafe@romulus.ehs.uiuc.edu writes:
 >
 >Date: Wed, 28 Oct 1998 13:36:15 -0700
 >From: "Sorensen, Scott" <ssorensen@doeal.gov>
 >To: "'RadSafe'" <radsafe@romulus.ehs.uiuc.edu>
 >Subject: RE: Does Size Matter?
 >Message-ID: <199810282029.AA11854@interlock.doeal.gov>
 >
 >Does size matter?  Radiation dose from whole-body irradiation, expressed
 >as Sv (J/Kg) or Rem (ergs/g), basically is an average energy-deposition
 >concentration (on a macro scale).  As such, the more mass a person has,
 >the more energy that is deposited.  The more energy deposition, the
 >greater the number of free radicals (i.e., reactive species) generated.
 >The more free radicals floating around, the greater the probability for
 >adverse interactions with cell nuclei,  thereby initiating
 >carcinogenesis.  This seems to indicate that, for stochastic processes,
 >size does matter.
 >
 >Another way of looking at this question is considering target areas.
 >Larger, non-obese people tend to have physically larger and more massive
 >organs than smaller individuals.  Therefore, the number of radiation
 >interactions within sensitive organs should be higher for larger people,
 >given the same energy fluence.  Once again, it seems that size dose
 >matter when looking at stochastic radiation effects.
 >
 >This is probably too simplistic...?    Any additional thoughts?
 >
 >-Scott Sorensen
 >ssorensen@doeal.gov

By this logic, whales don't have a chance of surviving their potassium load,
and mice could scurry around inside nuclear reactors with impunity.  Kinda
makes you wonder about LNT, doesn't it?

If you have two Siamese twins connected only by circulation and either one gets
a cancer that metastasizes the other one dies, i presume.  It seems likely that
the probability of getting a tumor, per unit mass of tissue, is some fairly
high power of the radiation dose per unit volume.

-dk
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