Re: linear hypothesis

["ALDEN N TSCHAECHE" <XAT@inel.gov>]

Thanks for your 5 points. Yes, the linear hypothesis is used for other
potentially harmful agents, particularly chemicals, by the EPA
especially. However, ALARA is not. Just wait until EPA mandates ALARA
for chemicals. One can't "prove" safety if the background is too high.
Most chemicals don't have a natural background so it is easier to
"prove" safety than for radiation where the background gets in the way.

Yes, the debate is about ALARA at BRC doses. I'm suggesting 5 rem per
year is the BRC dose. Use ALARA ABOVE that value, not below. Then study
prospectively those whose doses exceed the BRC value to see if there are
any harmful effects.

The linear hypothesis is NOT scientific interpretation to my mind. It is
only that, an hypothesis, undemonstrated and with some evidence that it
is not valid. I was always taught that, when just one piece of data did
not fit a particular hypothesis (or theory), that one piece of data is
enough to disprove the hypothesis and the hypothesis should be revised
or discarded. Is not what others were taught?

 The Eagle Alliance was formed to do exactly what you are suggesting,
tell the public about the benefits of the nuclear industry, among other
things. Have you read the Declaration of Interdependence? Ask the ANS
for a copy. By-the-by, does anyone know what the Eagle Alliance is doing
these days. I haven't seen anything about it since the Summer, 95 ANS
meeting.

You're right. It is up to us to show the public the benefits of the
nuclear industry. What would you be willing to do to do that? Al.

*** Reply to note of 10/17/95 11:47

From: David Scherer
To: RADSAFE --INELMAIL RADSAFE

Subject: Re: linear hypothesis
I think a few points are in order in this discussion.

(1) The linear hypothesis applies to stochastic risks.  Drug overdoses are
presumably nonstochastic.  I believe that a linear, non-threshold model is
used for Pb exposure as the basis of the current drinking water standards,
so it isn't only radiation.

(2)  Public health rules almost never wait for a potential hazard to be
proven before they are controlled.  When drugs or medical devices are
developed, they must be proven to be safe, not the other way around.  The
onus is not on proving radiation risks.

(3)  The linear hypothesis simply says that risks are observed to be linear
at high doses, so they should be presumed to be linear at low doses.  A
simple statement of the state of knowledge and uncertainity.  It seems to me
that the main rub is not this principle, but its societal application, the
ALARA principle.  The debate should be this: How do we apply the ALARA
principle at very low doses?  I think BRC is a sensible approach, somewhere
in the 10s of mrem/y range.

(4)  I don't think we should play with scientific interpretation to achieve
changes in ALARA.  Ultimately this approach is likely to be
counterproductive, especially if the radiation biologists do not sign on.
Credibility is our only stock in trade.  Environmental groups have it while
industry does not.  Let's not make matters worse.

(5)  The public does not always demand absolute safety, especially when they
perceive some benefit from the risk.  In the lower 50, we no longer have a
national 55 mph (88 km/h) speed limit, even though the death rate is
expected to rise.  It is our job to show the public and their leaders how
they benefit from radiation sources, and what the efffects of excessive
regulation are.

Dave Scherer
scherer@uiuc.edu