Re: how many sensitive cells?

[hwade@triax.com (H. Wade Patterson)]

Lester.Slaback@nist.gov wrote:
> 
> Wade's quotes relate to a question that I have never
> gotten a clear answer )primarily because I have not been
> willing to stand uyp and ask the dumb question at the
> appropriate forum).  That is,  why is individual radiation risk related to
> specific energy (dose, energy per unit mass) and
> not total energy absorbed?
> 
> The conclusion that I have come to is that specific energy is simply a
> convenient way to do measurements and that to a
> first approximation every wieghs the same (within +/- a factor of two).
> And if one threw out the body water, fat content, and  other nonsentive
> body components (which are not risk
> contributors via radiation produced changes)
> then the distribution is probably even tighter.  So to a first
> approximation most adults can be treated the same in terms of target
> cells.
> 
> Has anyone seen data or arguments along this line, or
> is this a really dumb approach to the above question?
> (This is really a Friday topic.)
> --
> the above are the personal musing of the author,
> and do not represent any past, current, or future
> position of NIST, the U.S. Government, or anyone else
> who might think that they are in a position of authority.
> NBSR Health Physics
> NIST
> Gaithersburg, MD 20899
> 301 975-5810
> -----------------------------------------------------------
> Lester.Slaback@nist.gov
> -----------------------------------------------------------

Les and all:
In my view present MPE's are set under the assumption that a single
event at the cellular level can give rise to cancer. From this
assumption arises the concept of collective dose and the policy of
ALARA.

The use of specific energy (dose/gram) also rests on this unsupported
assumption. Further it would make no difference if total energy was used
instead because the assumption has no biological basis.

I have shown in my March HP paper that this assumption is promulgated by
UBIN, in spite of the existence of much contradictory evidence.

The bottom line is that risk should be related to measurable physical
quantities such as fluence and energy, not on quantities which cannot be
measured such as Sv and Gy.


-- 
Wade

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H.Wade Patterson
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