[ RadSafe ] The Role of Low-Dose Radiation in the Maintenance of Life

[John Jacobus]

Dr. Scott,
I assume that this is not a comment regarding my
technical or creditial qualifications to read and
comment on the scientific literature.  I was not aware
that there was such a requirement to post on this list
server.

Unfortuantely, I have not had the opportunity to have
a position to do any academic research.  After 20
years in the Navy and a year at a medical facility in
Texas as a junior medical physicist, I have been
working at a major, governmental biomedical researche
insitiute for the last 11 years.  Most of my work has
involved ensurance compliance with regulations and
various aspects of medical health physics.  I have
been a jack-of-all-trades and a master of none.  (Or
something like that.) I have made presentation at
professional meetings, and have written numerous
training lectures, so I try to keep up with the
literature as best as I can.  

In my graduate training and subsequent education, I
have come to the conclusion that biological effects
can, as in physics, be viewed as a responding on a
continuum.  Effects seen as low doses are probably
occurring at high doses.  As I am sure you are aware,
the initial response to high dose radiation, there is
initial spike of immune cell response following by a
gradual reduction associated with the classical
clinical course of the hematopoietic syndrome. 
http://www.annals.org/cgi/content/full/140/12/1037/F4
The response will probably follow the dose through
both high and low dose ranges.  

By the way, you never did answer my question as to
what you consider to be a low dose of radiation?  I
tend to consider doses of below 100 mGy to be low
doses.  

Again, money being poured into low dose studies will
certainly improve our knowledge of biological
mechanisms and responses.

--- "Scott, Bobby" <BScott at lrri.org> wrote:

> Thanks John for your additional comments:
> 
> Have you published any recent papers in
> peer-reviewed journals that
> address radiation-induced stochastic effects?  If
> so, I would be
> interested in reading such publications.  Possibly
> others readers of the
> Radsafe Digest may also have interest so that you
> may want to post the
> list on Radsafe Digest.
> 
> Bobby Scott
> 
> -----Original Message-----
> From: John Jacobus [mailto:crispy_bird at yahoo.com] 
> Sent: Friday, November 03, 2006 1:50 PM
> To: Scott, Bobby; radsafe at radlab.nl
> Cc: charles l sanders
> Subject: RE: [ RadSafe ] The Role of Low-Dose
> Radiation in the
> Maintenance of Life 
> 
> Dr. Scott,
> Thank you for the reply.  Yes, I understood that you
> are not involved with human research.  Nevertheless,
> I
> think the work you are doing is important if not for
> the same reasons you do.  I resently attended a
> lecture by Dr. William S. Dynan of the Medical
> College
> of Georgia on the repair of ionizing
> radiation-induced
> DNA double-strand breaks and implication for
> therapeutic treatment.  The work was funded in part
> by
> the DOE low-dose program.  
> 
> Nevertheless, nothing that you write about Low dose
> effects and the fear of radiaiton is really not that
> new.  I and others have heard the arguements before.
> 
> I am not impressed by the claims.  I am certainly
> willing to change my mind, but so far the human data
> does not appear to me to be that significant.  
> 
> I have been in radiation safety and health physics
> since 1975.  I have and currently answer questions
> people have about medical exposures to themselves
> and
> their children.  Not once have I heard them mention
> the LNT.  They do have concerns about radation
> exposure, and I try to respond to their concerns
> directly.  We know that there are no observable
> effects below 10 rem.  All the research on cells,
> tissues and mice is not their concern.  The adaptive
> response is certainly evident, but they did not get
> a
> stimulating dose before their medical x-ray.  Do you
> get a stimulating dose before a medical or dental
> x-ray?  
> 
> 
> 


+++++++++++++++++++
"Give me your tired, your poor, 
Your huddled masses yearning to breathe free, 
The wretched refuse of your teeming shore, 
Send these, the homeless, tempest-tost to me, 
I lift my lamp beside the golden door!" 

>From "The New Collossus" by Emma Lazarus

-- John
John Jacobus, MS
Certified Health Physicist
e-mail:  crispy_bird at yahoo.com


 
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