Re: Radiation hormesis, thresholds, etc

[William V Lipton <liptonw@dteenergy.com>]

The point is that if we had a reasonable threshold, we wouldn't have to worry
about collective dose.  This worries some people, because it would force health
physicists to do real work, i.e. protecting people from  real hazards, instead
of compiling impressive, but meaningless calculations, charts, and graphs.  Are
we ready for that?

LNT is "extremely convenient" to those who want to avoid this.

The opinions expressed are strictly mine.
It's not about dose, it's about trust.

Bill Lipton
liptonw@dteenergy.com


Christoph_Hofmeyr/CNS1@cns.co.za wrote:

> Dear Radsafers,
> 0.  I wrote a draft response to Glenn Carlson in May (3.), but now a few
> related thoughts have accrued.   I hope it is not too heavy - my own
> musings.  Sorry about the delay.
> 1.  It might be useful to point out that from an RP perspective the LNT is
> extremely convenient, allowing concepts like collective dose to be used
> 'constructively'.  The concept of a threshold would require a very
> significant adaptation in thinking and doing.  Collective dose
> (man-Sieverts) would become meaningless as an expression of risk, except
> where individual doses are well in excess of the threshold.  Then, to a
> dose accrued over what period would the threshold apply?  When are the
> counters reset?  Does it apply to acute or chronic exposures?  If it is a
> lifetime phenomenon, and incremental dose is deleterious once you have
> passed the optimum?  These questions would have to be addressed
> satisfactorily before a new RP strategy can be developed.  Health Physics
> might well change to Health Math.
> Chris Hofmeyr
> chofmeyr@cns.co.za
>
> Original communication:
>
> Subject:  Re: Radiation hormesis
>
> In a message dated 5/6/99 1:06:16 PM EST, tmohaupt@wright.edu writes:
>
> << Glen presents an interesting point of view.  Since ionizing radiation
>  is simply a form of energy, it can be readily compared with other
>  forms of energy and their effects.  Keep in mind that there is no
>  type of energy that is safe in high levels.  Radiation is the only
>  one to which a LNT is applied.  The LNT is a political
>  position and, most likely, not an accurate description of reality.
>  Personally, I'd like to see radiation regulated to prevent real
>  damage, much the way we do with other forms of energy, rather than
>  treat it like the witchcraft trails of the late 17th century in New
>  England. >>
>
> My issue is not whether LNT, or LT, or NLT, or NLNT is the more accurate
> model for calculating risks from radiation exposure, but, rather, how any
> alternative to LNT would be implemented.
>
> Let's ASSUME the LNT model for radiation exposure is invalid, and, say,
> there
> is a threshold exposure below which increasing exposure produces no
> increasing or, even, a decreasing risk of excess cancer, and, above that
> threshold, increasing exposure results in increasing risk.
>
> Do we agree, then, that exposures above that threshold should only be
> permitted if the increased risk is outweighed by some benefit?  And, do we
> also agree that exposures below that threshold may be permitted without
> regard to whether there is a corresponding benefit?
>
> Now, assuming we agree up to this point, my question is:
>
> How is one to determine for which situations the cost-benefit analysis must
> be done (i.e, the NET benefit of the exposure MIGHT be negative) and for
> which the cost-benefit analysis need not be done (i.e, the NET benefit of
> the
> exposure CANNOT be negative)?
>

...


>
> Glenn
> GACarlson@aol.com
>

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