My focus here is on the possibility of radiation hormesis, and what it should mean for
health protection standards.
I think that it’s pretty important to base our policies on facts as we can determine them,
with allowance for our lack of complete knowledge. Obviously, this can be difficult; people are
ornery critters, and sometimes can’t agree on anything.
A recent example of this was the CERRIE (pronounced “Cherry”, Committee on the Risks
of Radioactive Internal Emitters, or something similar) report in the UK.
This was supposed to determine areas of agreement between Regulator, Academic
Scientist, and “Deep Green” board factions. My impression was that the Greens couldn’t agree
with the others on anything of importance, and made a dissenting report of their own.

It looks to me, that there isn’t any really strong scientific consensus as to what the shape
of the dose response curve is. I understand that the regulations call for human exposures to be
kept “as low as reasonably possible” (the ALARA standard), and that exposure is kept so low that
it’s hard to tell whether anyone is hurt (or possibly helped) at all. Some people (health physics
people, I mean) seem to believe the Linear-No Threshold Hypothesis is Gospel; a lot of others
seem to reserve judgement, and a vocal minority believe that low doses, like 30 times average
background, are beneficial.
While I would love to believe this last, the “hormetic” dose idea, I realize that what I
want and what Nature actually does, are two entirely different things.
I have seen a number of graphs that are supposed to show the dose-response risk curve,
and my problem is that I don’t know what datasets to believe.
For example, I have seen the critics’ plotting of the Miller et al dataset. This shows a strong dip in
breast cancer rate, near 10 Roentgens total dose. This is claimed by some of the hormesis
advocates to be where the data was most plentiful and significant. Yet the study was originally
billed as proof of Linear No Threshold., and was originally published by the New England
Journal of Medicine without showing this data plot. See the graph at:

http://www.21stcenturysciencetech.com/articles/radiat3.html

The graphs in the pdf file of the Chen et al article are even more striking…But while I am
not aware of anyone saying they aren’t correct, the Journal of American Physicians and Surgeons
has a bad rep, and is supposed to be attractive to cranks. Dang.
See:

http://www.jpands.org-vol9-no1-chen.pdf

On the other hand, there was an article in the British Medical Journal which surveyed 15 studies,
and considered ionizing radiation dangerous down to low levels… but admitted that discarding
only the Canadian study would make their results statistically not significant.
(This was from a link
on the http://www.world-nuclear.org site, but I no longer have the url info.)
So here I am: I think this is a trillion dollar question, and I can’t discover the truth of the matter.
I would love to have someone shed some real light on this.

See also:

Australasian Radiation Protection Society Newsletter, No.30, April 2004.
Lessons of Chernobyl – with particular reference to thyroid cancer
by Zbigniew Jaworowski
Central Laboratory for Radiological Protection – CLOR, Warsaw, Poland
Excerpt from summation:

(5) This was the worst possible catastrophe of a badly constructed nuclear reactor, with
a complete meltdown of the reactor core, followed by the ten-days long completely free
emission of radionuclides into the atmosphere. Nothing worse could happen. It resulted
in a comparatively small occupational death toll, amounting to about half of that of each
weekend’s traffic in Poland, and tens or hundreds of times lower than that of many other
industrial catastrophes, and it is unlikely that any fatalities were caused by radiation
among the public. In the centuries to come, the Chernobyl catastrophe will be seen as a
proof that nuclear power is a safe means of energy production.
From:
http://www.world-nuclear.org/info/chernobyl/jaworowski.html

Hormesis is one of the things I plan to write about. Mostly trying to take some of the more technical papers and reducing them to everyday language.

Stay tuned and try out that RSS thingie if you like. I think it works.

John