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

John Jacobus crispy_bird at yahoo.com
Mon Nov 13 16:02:55 CST 2006

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

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. 
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

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

Do you Yahoo!?
Everyone is raving about the all-new Yahoo! Mail beta.

More information about the RadSafe mailing list