[ RadSafe ] LNT and AGW - continued

Miller, Mark L mmiller at sandia.gov
Fri Sep 30 11:06:05 CDT 2011

Perhaps a way to move the discussion of the LNT versus hormesis forward is to borrow some terminology from the widely used,  accepted and understood Multi-Agency Radiation Site Survey and Site Investigation Manual (MARSSIM).   As all of us know, understand and do not dispute, high-dose and high-dose-rate exposures to radiation can be lethal and can cause cancer.  However, the science for low-dose and low-dose-rate exposures is not so clear. The Health Physics Society states in its Risk in Perspective<http://hps.org/documents/risk_ps010-2.pdfhttp:/hps.org/documents/risk_ps010-2.pdf>, “estimates of risk should be limited to individuals receiving a dose of 5 rem in one year or a lifetime dose of 10 rem in addition to natural background. In making risk estimates, specific organ doses and age-adjusted and gender-adjusted organ risk factors should be used. Below these doses, risk estimates should not be used. Expressions of risk should only be qualitative, that is, a range based on the uncertainties in estimating risk (NCRP 1997) emphasizing the inability to detect any increased health detriment (that is, zero health effects is a probable outcome).”

In MARSSIM, the gray region is defined as a range of values of the parameter of interest for a survey unit where the consequences of making a decision error are relatively minor.   For the purpose our discussion, this would be low-dose and low-dose-rate radiation exposures where there is not likely to be a quantifiable dose-response effect.

In MARSSIM, the lower bound of the gray region (LBGR) is the minimum value of the gray region. By way of analogy, the “lower bound of the gray region” for radiation exposure is, for all practical purposes, anything less than 5 rem in one year or 10 rem per lifetime.  Anything above that is in the “gray region” where radiation effects may or may not be quantifiable, but which prudent radiation protection dictates that additional exposure be limited or prevented.  Above the gray region is the high-dose and high-dose-rate area where there is an undisputed linear dose-response.

Part of the problem is that ICRP 26, 60 and 103 state that there is precisely non-zero risk for any exposure. This is false.  We should all agree to work productively without dispute in situations below the LBGR (where there is currently meaningless, rancorous debate) and concentrate our efforts and passion for radiation exposures in the "gray region" and above.  The result would be billions of dollars saved on needless "protective measures", psychological distress over inconsequential exposures and better radiation protection in situations where it really matters.

*Footnote: DCGL (derived concentration guideline level) is a derived, radionuclide-specific activity concentration within a survey unit corresponding to the release criterion.  DCGLs are derived from activity/dose relationships through various exposure pathway scenarios.

Mark Miller
-----Original Message-----
From: Jerry Cohen [mailto:jjc105 at yahoo.com]<mailto:[mailto:jjc105 at yahoo.com]>
Sent: Tuesday, September 27, 2011 4:18 PM
To: The International Radiation Protection (Health Physics) Mailing List
Subject: Re: [ RadSafe ] LNT and AGW

For the same reason that advocates of LNT can never be proven wrong, those who
push the Global  Warming agenda can feel safe from contradiction.
You cannot prove a negative!
The same holds true for  those who warn us about global cooling.
So, the climate debate may also continue forever. The only thing we can be sure
of is continuing controversy.
OTOH, if we all agreed on everything, life could get dull.
From: Jerry Cohen <jjc105 at yahoo.com<mailto:jjc105 at yahoo.com>>
To: The International Radiation Protection (Health Physics) Mailing List
<radsafe at health.phys.iit.edu<mailto:radsafe at health.phys.iit.edu>>
Sent: Mon, September 26, 2011 1:50:41 PM
Subject: Re: [ RadSafe ] LNT

Those who do not subscribe to LNT have the same problem as atheists.
Just as it cannot be proven that there is no God, it cannot be proven that
there are no harmful effects from low-dose radiation exposure.
Philosophically, a negative can never be proven.
So, it seems the debate may continue indefinitely.
From: "Brennan, Mike (DOH)" <Mike.Brennan at DOH.WA.GOV<mailto:Mike.Brennan at DOH.WA.GOV>>
To: The International Radiation Protection (Health Physics) MailingList
<radsafe at health.phys.iit.edu<mailto:radsafe at health.phys.iit.edu>>
Sent: Mon, September 26, 2011 10:24:40 AM
Subject: Re: [ RadSafe ] Researcher Points to Suppression of Evidence On
Radiation Effects by Nobel Laureate

Without intending to disparage anyone on any side of the issue, reading
someone's archived correspondence doesn't necessarily give you complete
insight into their thoughts and motivations, and publishing "key
excerpts" does not always capture the truest picture.

But regardless of what was thought or known or believed in the 1940s, it
is time to systematically revisit Linear No Threshold.  LNT is at its
heart a statistical argument, and there is perhaps no single field in
which the available tools have changed so much as our ability to
manipulate lots and lots of numbers.  Even if there were no basic
disagreement about the validity of LNT, it would STILL be time to look
at it again more closely.

I believe that it shouldn't be too difficult or expensive to put
together an experiment that will have the power to pretty much answer
the question about LNT's legitimacy.  The trick is that it should not be
done by people who think LNT is wrong, or by people who think it is
right.  Instead, several researchers with enough street cred to make
people listen, and who are on opposite sides of the issue, should get
together and design the experiments together.  If they work to make sure
that all possible objections are addressed before the experiment
actually begins, they should produce something truly impressive.  Yes,
someone will be proven wrong, but they will have been proven wrong in
the best possible way, and any prestige they loose from being wrong will
be more than replaced by being shown to be scientists in the finest

So, someone out there; get to it.

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu<mailto:radsafe-bounces at health.phys.iit.edu>
[mailto:radsafe-bounces at health.phys.iit.edu]<mailto:[mailto:radsafe-bounces at health.phys.iit.edu]> On Behalf Of Miller, Mark L
Sent: Thursday, September 22, 2011 4:04 PM
To: The International Radiation Protection (Health Physics) Mailing List
Cc: Johnson, Dr. Janet @ MFG; Roberts; Glenn at agni.phys.iit.edu<mailto:Glenn at agni.phys.iit.edu>; Bob
Meyer; Little, Bonnie Colleen; Mark Miller @ home
(marklmiller at comcast.net<mailto:marklmiller at comcast.net>)
Subject: [ RadSafe ] Researcher Points to Suppression of Evidence On
Radiation Effects by Nobel Laureate

No Safe Level of Radiation Exposure? Researcher Points to Suppression of
Evidence On Radiation Effects by Nobel Laureate
ScienceDaily (Sep. 20, 2011) - University of Massachusetts Amherst
environmental toxicologist Edward Calabrese, whose career research shows
that low doses of some chemicals and radiation are benign or even
helpful, says he has uncovered evidence that one of the fathers of
radiation genetics, Nobel Prize winner Hermann Muller, knowingly lied
when he claimed in 1946 that there is no safe level of radiation
Calabrese's interpretation of this history is supported by letters and
other materials he has retrieved, many from formerly classified files.
He published key excerpts this month in Archives of Toxicology and
Environmental and Molecular Mutagenesis.
Muller was awarded the 1946 Nobel Prize in medicine for his discovery
that X-rays induce genetic mutations. This helped him call attention to
his long-time concern over the dangers of atomic testing. Muller's
intentions were good, Calabrese points out, but his decision not to
mention key scientific evidence against his position has had a
far-reaching impact on our approach to regulating radiation and chemical
Calabrese uncovered correspondence from November 1946 between Muller and
Curt Stern at the University of Rochester about a major experiment that
had recently evaluated fruit fly germ cell mutations in Stern's
laboratory. It failed to support the linear dose-response model at low
exposure levels, but in Muller's speech in Oslo a few weeks later he
insisted there was "no escape from the conclusion that there is no
threshold." To Calabrese, this amounts to deliberate concealment and he
says Stern raised no objection.
Calabrese adds, "This isn't an academic debate, it's really practical,
because all of our rules about chemical and low-level radiation are
based on the premises that Muller and the National Academy of Sciences'
(NAS) committee adopted at that time. Now, after all these years, it's
very hard when people have been frightened to death by this dogma to
persuade them that we don't need to be scared by certain low-dose
Within a year after Muller and his group persuaded the NAS to accept the
linear model for gonadal mutations, the practice was extrapolated to
somatic cells and cancer. Twenty years later, NAS adopted the linear
approach for chemicals. Soon thereafter, the U.S. Environmental
Protection Agency announced it would use the linear model for risk
assessment, Calabrese points out.
Some can accept that even the most distinguished scientists have human
failings, he acknowledges. But his view is that "the regulatory research
community needs to hear about this. The implications of my findings are
that we should revisit our exposure regulations because our regulatory
history is founded on a deception. We have seen literally hundreds of
thousands of cleanup decisions based on a model that was fraudulently
derived. I think we should probably have drastically different exposure
standards today, and far less fear."
Calabrese believes, "The die was cast by Muller and regulations adopted
since then have gone unchallenged. I think he got his beliefs and his
science confused, and he couldn't admit that the science was unresolved.
So he went ahead and expressed an opinion about how to handle the public
health situation."
Geneticists in the 1950s came to embrace the "linear dose-response
model" of risk because at the high exposures they tested, there was no
level below which DNA damage did not occur. They felt medical doctors
didn't grasp how significant were the dangers. As the smartest and
brightest, Muller anticipated the risk of atmospheric atomic testing and
became passionately committed to protecting society, Calabrese explains.
Muller and Curt Stern had done many of the key experiments. Muller
himself served on the NAS's Biological Effects of Atomic Radiation
(BEAR) committee, through which the linear dose-response approach to
risk assessment became firmly entrenched. The two successfully
suppressed last-minute evidence from the fruit fly experiment conducted
in Stern's lab by postdoctoral researcher Ernst Caspari, and the rest is
history, Calabrese says. It marked the "transformation of a
threshold-guided risk assessment to one now centered on a linear
"To me this all raises the question, what happens when a scientific
field lies to the public, to federal agencies and the president? It's a
very scary situation that the radiation genetics community in the 1950s
assumed that something was correct without requiring the necessary
documentation to support it," the UMass Amherst toxicologist says.
Stern's group published a paper in 1947 not long after Muller's Nobel
Prize acceptance speech in which they tried to discredit their own
study, further evidence of a deliberate cover-up, Calabrese says. "It's
been hidden in the bowels of the Atomic Energy Commission for decades
until I found it. They revised it to remove the one sentence suggesting
this experiment might provide evidence for the threshold model."
"One could argue that Muller single-handedly undermined above-ground
atomic testing, which is a good thing," Calabrese says. "But after
uncovering this lie, I'm starting to contemplate what society would have
looked like if the regulatory community had felt free to use a threshold
model. Members of that 1956 NAS BEAR committee didn't see the domino
effect of their

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