Re: Low Doses, Ethics and LNT

["David W. Lee" <lee_david_w@lanl.gov>]

At 10:49 AM 12-08-97 -0500, you wrote:
>
>
>From: Paul E Ruhter@INEL on 08/12/97 09:41 AM
>
>
>To:   radsafe@romulus.ehs.uiuc.edu
>cc:
>Subject:  Low Doses, Ethics and LNT
>
>
>Les Slaback's comments over Sandy Perle's thoughts were intriguing.
>However, I find plinking at golf balls much less frustrating than
>keyboards; at least you can see progress, if not necessarily in the right
>direction.
>
>Along the lines of "Has anyone else noticed?"   -  During the discussion of
>LNT over the last week or so, the tone was generally that low doses were
>likely not harmful, maybe beneficial (my liberal paraphrase to emphasize
>the point). However, during the recent discussions of Low Doses and Ethics,
>the tone seems to be that Low Doses should be reduced in the interest of
>ALARA and eliminating unnecessary (harmful) exposures(again, liberal
>paraphrase).  In part, it is different groups involved in the discussion,
>but it seems like we are talking out of both sides of our mouths, or at
>least in different directions.  Are we having trouble believing our own
>rhetoric?
>
>More and more data (almost overwhelmingly) support that LNT is no longer a
>reasonable "assumption". The HPS hit a Tiger Woodsian Drive dead center
>perfect with its Position Statement concerning risk estimates below 5 rem/y
>or 10 rem/lifetime, but now we can't seem to decide if we are going to hook
>or slice the next shot. Let's hit it straight, advance the ball!!!!!!  We
>are making a significant paradigm shift, but we need to make it thoughout
>all the logic, not just in parts of it.  It doesn't make sense to say, on
>the one hand, that risk estimates at low doses are not scientifically
>valid, while on the other hand advocating that we should expend resources
>to reduce them.  There is no longer a valid basis to make  ALARA decisions
>at these levels, so spend those resources in a more fruitful endeavor.
>(Like plinking golf balls!!!)
>
>The usual, intuitively obvious but regrettably needed, reminder that I
>        alone am responsible for the contents of my messages!
>
>        Paul E. Ruhter   CHP
>        Supervisor, Radiation Dosimetry & Records
>        Lockheed Martin Idaho Technologies Company
>        Idaho National Engineering & Environmental Laboratory (INEEL)
>        e-mail:   ruh@inel.gov
>
>
>	I certainly did not intend for my recent RADSAFE contributions on this
issue to come across as equivocal.  Not wishing to appear to be talking out
of both sides of my mouth, perhaps the following will further clarify my
recent proposals.

	I feel that institutional radiation safety program performance standards
should incorporate a recognition of the dose/dose rate that all of us
inevitably receive from the natural radiation background, reasonable
multiples of which have never been found to produce any "ill health"
effects.  Accordingly, I would suggest that federal radiation safety
standards contain NO "member of the public" maximum permissible dose nor
any "pregnancy" limit.  The present 5 rem/yr WB limits and the
organ/extremity limits are already plenty conservative.

	"Revised" federal radiation safety program standards would require that
the institutional Radiological Control Organization (RCO) specify, say in
their NRC license application or in their written Radiation Protection
Program document (DOE), and adopt a Radiation Safety Program "Action Level"
which would be some reasonable multiple of the natural radiation background
dose.  I have suggested 2 to 3 times 300 mrem/yr due to the variation in
the "mean" background levels across the world, not even higher multiples of
which having been found to cause "ill health" effects.  For a nice round
number in this discussion, call the "Action Level" that a hypothetical
institution chooses to adopt "1 rem/yr."

	Then, the institutional RCO, performance wise, would be required to
carefully analyze its radiological operations to whatever degree necessary
to verify that radiological workers were not sustaining annual doses on the
order of 1 rem/yr.  If they were not, the RCO could conclude that it had
sufficient worker training/proficiency and workplace controls in place--a
total radiological safety envelope--that was "good enough"; ALARA would not
be applied any further to that particular radiological operation or to the
doses of the radiological workers involved, etc.

	On the other hand, if a given radiological operation was found to exceed
the 1 rem/yr "action level," then the RCO would be required to devote
considerable effort/resources to mitigate the workplace circumstances such
that the worker doses eventually were documented to be below the "action
level."  
	
	The ALARA philosophy would still have its place, it simply would not be
applied below 1 rem/yr in recognition of the fact that people throughout
the world, depending on the geographical variation of the "mean" background
dose, already sustain in the course of daily "living" a dose on the order
of a reasonable multiple of the "mean" background dose with no ill health
effects, etc.

	I sincerely hope other RADSAFERS choose to respond to this seemingly
"heretical" proposal.  Pending such wiser counsel in this regard, I am
having difficulty at this end discerning how the above proposal would be so
difficult to accept or be judged to be "unrealistic" or "unreasonable."
Also, since "overbadging" is so rife throughout the nuclear industry, as a
result we already have a excellent handle upon the doses received by
virtually all radiological workers.  The totality of these results
basically document the fact that radiological workplace controls are
already in place such that the VAST majority of all radiological workers
sustain on an annual basis substantially less than  1 rem/yr.  In other
words, it probably is not reasonable to worry that under the above "action
level" method that there would be radiological workers in the future who
would routinely come close to the action level or seriously approximate the
10 rem lifetime figure cited by Paul Ruhter, above.  A bit of flexibility
is also available in the above outlined system in that an institution would
be allowed to choose, within reasonable limits, whatever multiple of the
natural radiation background dose they wanted as their "action level."
>
Best regards  David


David W. Lee
Los Alamos National Laboratory
Radiation Protection Services Group (ESH-12)
PO Box 1663, MS K483
Los Alamos, NM  87545
PH:   (505) 667-8085
FAX:  (505) 667-9726
lee_david_w@lanl.gov