Re: radsafe posts

[JMUCKERHEIDE@delphi.com]

David Scherer <scherer@uiuc.edu> writes: 

> Jim:
> 
> Dose Equivalent:  We use DE in radiation protection as part of our effort to
> control worker exposures.  As I mentioned earlier, we could keep records of
> each type of exposure and develop some formula for looking at a combined
> risk.  This would be quite complex without achieving any added safety.
> Instead, we combine occupational exposures of different radiation types
> using the DE.  This can be useful even if the Q values are subjective.
> After all, they are essentially safety factors.  When a structural engineer
> designs a bridge, there is no objective, scientific method for selecting the
> safety factor she will incorporate in the design.  A design basis is
> selected based on the compressive strength of concrete AND an arbitrary,
> perhaps unknown, safety factor added.  I'm not going to demand that bridges
> be built only to the design basis!

As before: no problem for "safety factors". But they don't change the units
nor pretend to be scientifically valid, as q (wR) do. 

> The problem comes in when we use DE in radiobiological or emidemiological
> experiments.  So we calculate DE for radium or radon exposures using Q with
> all these safety factors.  Of course we don't see cancers associated with
> radium or radon exposures.  In the structural analogy: suppose a bridge is
> designed to hold a 10 ton load plus added safety factor(s).  The engineers
> want to test the theory so they drive a 10 ton truck onto the bridge.  The
> bridge does not crumble, so the engineers conclude the compressive strength
> of concrete is not accurately known!

Not true. Thousands of experiments carefully measuring to destruction the
compressive strength of many concretes and physical conditions go into
establishing scientifically valid values that get written into engineering
codes, to which are applied "safety factors" (that do not pretend to reflect
physical reality). The lack of equivalent research in rad science is the
direct result of failing to find similar responses. See the research with mice 
populations exposed at a low dose range of 0.11 r/day in which they lived
longer and were healthier. Research policy ignored the data and failed to
follow recommendations of many true scientists who recommended more definitive 
studies. 

> Public Perceptions:  I disagree with you that public fear is caused by the
> linear model.  People are concerned about NOx levels in drinking water even
> when they are far below EPA standards.  The public does not feel safe
> because they use a threshold model.  Also, the statement that "No dose level
> is absolutely safe" does not cause the fear.  People are averse to normal,
> municipal landfills, even when no such statements apply.  Instead, people
> are afraid of the unknown, especially the high tech, manmade, unknown.  The
> aversion is compounded when they have no control over the matter, even if it
> is not especially hazardous.
> 
> I don't think public perception would be substantially altered if a
> threshold model were adopted by some scientific group or regulatory agency.
> In my experience people's attitudes are changed when they understand that
> radiation is natural, not manmade.  Most people can put the risks in
> perspective when they learn that they are exposed to about 100 mrem per year
> from natural, external radiation and an additional 200 mrem "equivalent"
> exposure per year from radon.  Then they seem to recognize that an
> additional 10-100 mrem from their work, etc. is truly trivial.

Perhaps you could teach NCRP? You have identified the problem, and solution,
but blame the victim instead of the perpetrator. If the scientists and the
policy-makers don't "understand", why would you tell the public and expect
them to understand? The public doesn't demand 10 mrem/year, and $100s
millions/year in unnecessary environmental measurements, they just want to be
safe. The policy-makers keep the public fearful by using the "linear model",
and working diligently _against_ the argument you make here about 10-100 mrem
being "truly trivial"! 

The issue is not "the model".  Most "threshold" rules, like the NRC BRC
proposal, are made by regulators and many in "science" not as "safe" but as
"to kill few", so activist publics freely and justifiably argue that case.
(Note that EPA doesn't make any equivalent case against coal and most
chemicals, though they've been forced into it on dioxin by activist court
cases. However, though coal plants kill thousands/year, the public does not in 
fact react like you say they do in an equivalent response to radiation fears
of totally inconsequential exposures. (That the EPA/DOE/NRC, etc etc then say
"the public makes us" -- and "the public" is paying $100 million at Hanford on 
dose reconstruction and "health effects study" and "public process" and the
"Hanford Health Information Network" to keep the pot of "public support"
stirred!  I'm a "down-winder", '46-'49, so I'm sure they're doing it for my
benefit :-) 

When "thesholds" are established because science shows no adverse health
effects (eg, zinc in your vitamin pills?) then there is no serious public
concern. Rad science policy has ignored that evidence, and prevented
applicable research, for almost 30 years. People at Oak Ridge in the '60s and
'70s knew that explicitly, including from my own experience with Norm
Frigerio! And up to the present in the killing of the ANL radium program, the
failure to publish the Shipyard Worker Study, and DOE redirection and biasing
of the RERF program (needed to prevent similar termination).  (See who is
selected to be program directors, with very large funding; and the funding and 
publication of junk science as a political response to hard science.) 

The EPA campaign misleads the public about those radon effects you refer to
(buying another linear projection, followed by a national disinfo campaign,
while not supporting science on the uranium miners exposures and pathologies,
and politically and personally trashing Bernie Cohen's work without a single
substantive contrary comment about the scientific validity of his work, etc
etc); to be simply part of the campaign. The campaign seeks to destroy the
previous public confidence that you allude to here, that a small contribution
to background is "safe". What are we doing about it? (Besides those who are
leading the cheering?) 

> Regards,
> Dave Scherer
> scherer@uiuc.edu

Thanks Dave.

Regards, Jim Muckerheide
jmuckerheide@delphi.com