Re: Re[4]: how many sensitive cells?

[Lester.Slaback@nist.gov]

The following is the closest to addressing my question of whether risk is
proportional (i.e., not necessarily linear) to the number of cell exposed.

"In biology, cells don't exist in isolation. By using data from hits on
cells in cultures that do not have functional response capability, it is
easy to show "linear" responses. As soon as you take 4 cells with
communication, the response will not, can not be "linear". All the
framework of the biological assessment of "dose" as energy concentration
falls. This is part of the biological work that has been judiciously
ignored by the ICRP et al for the last 15-20 years, and longer if you go
back to the work of Brues and others. 

Regards, Jim Muckerheide"

This is easy to accept for cells within an organ or a limits region.  Is
it true for the whole organism, i.e., the whole body?  Is 1 cm2 of the
foot is exposed will the body reaction in effect make the response the
same as if 1 cm2 of each foot were exposed or does the later in fact
double the risk?

If the former is the case then the body reaction would seem to be one that 
must be communicated very the blood circulatory system as opposed to an
intracellular repair response.  I guess it is time to do some radiobiology
remedial reading. This sure is not addressed in the books I have.

-- 
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
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Lester.Slaback@nist.gov
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