Re: What would we do with a threshold? -

[vchase@bi-pharm.com]

    Tom Graham wrote:

    We do urgently need to save money for many useful things.

     I propose that ALARA and threshold concepts can and do work together.
     Simply put, some statements need to be made regarding what is
     REASONABLY ACHIEVABLE in broad terms.  In fact, our experience has
     shown that ALARA is not meaningful without a threshold.  As practicing
     health physicists, we do set limits to how far we look for a vanishing
     source term.  Similarly, the HPS position statement "works with" LNT
     giving guidance regarding at what point we cease to consider LNT
     projections towards zero.

     Technically, we act on the mathematical concept of "zero" as a limit
     we can only approach, no matter how small.  Most people have some
     fairly practical daily concepts of "zero" as readily achievable.  When
     the cookie is "gone," most of us do not search the floor for crumbs to
     be sure we ate the whole thing.

     It will never be easy, but we can continue to honestly call some level
     of risk "safe" and be prepared to defend the judgement, or more
     likely, defend the quotation.  I have not given up on the scientific
     communities as viable sources of useful information, interpretation,
     and credentials.

__________________________

I cringe every time words like "money", "cost savings", etc. are used
anywhere near the word "safe".  This only provides fuel for those who
believe zero is the only safe level for radiation.  They feel that dose
limits are raised only as a cost savings measure without any supporting
scientific evidence that the chosen level is safe.

Politicians  and regulators (especially the EPA)  will always demand
lower radiation levels as the "scientifically accepted" LNT model predicts
that lower is "safer",  which only provides fodder for the fear mongers.
Selecting any safe level to that is linked to the LNT model will only 
confuse
the public when the scientific feathers start to fly.

The public (who in the long run is the only entity we have to assure) cares
only if something is safe ... black and white...  no hemming and hawing...
no if's and's, but's... no scientific caveats, interpolations, 
extrapolations or
judgements.  I believe the only way a safe level of radiation can be
defended without reservation is if a threshold is demonstrated by
scientific method.

Regards,
Vince Chase
vchase@bi-pharm.com
Radiation Safety Officer
Boehringer Ingelheim Pharmaceuticals
The opinions expressed here are those of the author and do not represent
the opinions policies or practices of Boehringer Ingelheim Pharmaceuticals.