OT but interesting: a paper on the risks from low-dose radiation

On 06/05/2012 19:01, Rod Speed wrote:
Nightjar wrote
....
This one goes into more detail about radiation hormesis:

http://www.angelfire.com/mo/radioadaptive/inthorm.html

That's still controversial and unproven
http://en.wikipedia.org/wiki/Hormesis#Controversy

It is unproven because it is very difficult to justify giving humans low
doses of radiation over long periods to build up the amount of data
needed to prove it. Virtually all the data on the effects of radiation
come from the bombing of Japan and from nuclear accidents, all of which
involve acute doses. There is plenty of evidence that the LNT model is
unreliable at predicting the effects of low dose chronic exposure.
However, as it gives the most pessimistic predictions, it is likely to
continue to be used when setting safe exposure levels. That does not
mean it is right.

Certainly people living in areas with naturally high background levels
of radiation do not exhibit anything like the amount of cancer that
the LNT model suggests.

But that may be due to other effects, because cancer incidence
does vary so widely due to all sorts of other effects too.

Certainly there may be variations due to other factors, but the LNT
model predicts that there should be a minimum number of cases,
irrespective of other factors, and they don't get anywhere near that
minimum number.

Colin Bignell

Nightjar wrote
Rod Speed wrote
Nightjar wrote

This one goes into more detail about radiation hormesis:

http://www.angelfire.com/mo/radioadaptive/inthorm.html

That's still controversial and unproven
http://en.wikipedia.org/wiki/Hormesis#Controversy

It is unproven because it is very difficult to justify giving
humans low doses of radiation over long periods to
build up the amount of data needed to prove it.

That not how that sort of research is done.

Its done by considering the epidemiology of what
is seen with inevitable variation in natural and
unnatural radiation exposure that happens anyway.

Its actually unproven because there are lots of other
factors that affect the incidence of even just cancer etc.

Virtually all the data on the effects of radiation come
from the bombing of Japan and from nuclear accidents,

That's just plain wrong with the lower levels of radiation exposure.

The other obvious data is with areas which have much higher
than normal radiation levels, usually due to radioactivity in the
rocks in the area and to radioactive gases from those etc.

all of which involve acute doses.

And the areas with high levels of background radiation don't.

There is plenty of evidence that the LNT model is unreliable
at predicting the effects of low dose chronic exposure.

Yes, but hormesis is unproven anyway.

However, as it gives the most pessimistic predictions, it is likely
to continue to be used when setting safe exposure levels.

And that is the conservative approach that makes sense.

That does not mean it is right.

Certainly people living in areas with naturally high
background levels of radiation do not exhibit anything
like the amount of cancer that the LNT model suggests.

But that may be due to other effects, because cancer incidence
does vary so widely due to all sorts of other effects too.

Certainly there may be variations due to other factors,

And we know that there are.

but the LNT model predicts that there should be a
minimum number of cases, irrespective of other factors,
and they don't get anywhere near that minimum number.

Yes, but I was JUST commenting on hormesis.

On Sun, 6 May 2012 15:58:39 +0000 (UTC), J G Miller wrote:

If a simple test can also be developed for autism, should the unborn
who test positive also be killed like those with Down syndrome?

No.

Then people who no longer have the unpleasantness of dealing
with imbeciles.

Autism is a spectrum disorder and having it does *not* mean the
person is an imbecile. There is some thought that some of our
greatest scientists may have been autisic, Turing, Einstein,
Newton...

--
Cheers
Dave.

In article ,
Rod Speed wrote:

It is unproven because it is very difficult to justify giving
humans low doses of radiation over long periods to
build up the amount of data needed to prove it.

That not how that sort of research is done.

Yes, the research isn't done that way because it's hard to justify
doing it. If it wasn't hard to justify, the research would be done
that way, and it would no longer be unproven.

-- Richard

On Tue, 08 May 2012 12:22:17 +0200, Martin wrote:

On Tue, 08 May 2012 09:46:29 +0100 (BST), "Dave Liquorice"
wrote:

On Sun, 6 May 2012 15:58:39 +0000 (UTC), J G Miller wrote:

If a simple test can also be developed for autism, should the unborn
who test positive also be killed like those with Down syndrome?

No.

Then people who no longer have the unpleasantness of dealing
with imbeciles.

Autism is a spectrum disorder and having it does *not* mean the
person is an imbecile. There is some thought that some of our
greatest scientists may have been autisic, Turing, Einstein,
Newton...

... and then again they might not have been.

See this which mentions the arguments for and against:
http://en.wikipedia.org/wiki/Histori...dered_autistic

Einstein, Tesla and Newton

the "For" case

Arguments against

Despite having a lot of savant-like abilities, Nikola Tesla is more
likely to have had some form of OCD.

The evidence that any one of them had autism "seems very thin at
best", according to Oliver Sacks.[8] Glen Elliott, a psychiatrist at
the University of California at San Francisco, is unconvinced that
either of the scientists had Asperger syndrome, particularly due to
the unreliability of diagnoses based on biographical information.

--
Peter Duncanson
(in uk.tech.digital-tv)

Richard Tobin wrote
Rod Speed wrote:

It is unproven because it is very difficult to justify giving
humans low doses of radiation over long periods to
build up the amount of data needed to prove it.

That not how that sort of research is done.

Yes, the research isn't done that way because it's hard to justify doing
it.

The research is done another way, by observing where you do see significant
variation in low level radiation, as I said and you deleted from the
quoting.

If it wasn't hard to justify, the research would be
done that way, and it would no longer be unproven.

Irrelevant to how the research is done.

On 08/05/2012 09:45, Rod Speed wrote:
Nightjar wrote
Rod Speed wrote
Nightjar wrote

This one goes into more detail about radiation hormesis:

http://www.angelfire.com/mo/radioadaptive/inthorm.html

That's still controversial and unproven
http://en.wikipedia.org/wiki/Hormesis#Controversy

It is unproven because it is very difficult to justify giving humans
low doses of radiation over long periods to build up the amount of
data needed to prove it.

That not how that sort of research is done.

That is what I said.

Its done by considering the epidemiology of what is seen with inevitable
variation in natural and unnatural radiation exposure that happens anyway.
Its actually unproven because there are lots of other
factors that affect the incidence of even just cancer etc.

However, if an ethical committee were to approve a trial that involved
giving a very large number of humans controlled low dose chronic
exposure to radiation, it would eliminate most of the variables that
make that approach so unreliable. Not that an ethical committee would
approve clinical trials on penicillin if it applied current day standards.

Virtually all the data on the effects of radiation come from the
bombing of Japan and from nuclear accidents,

That's just plain wrong with the lower levels of radiation exposure.
The other obvious data is with areas which have much higher
than normal radiation levels, usually due to radioactivity in the
rocks in the area and to radioactive gases from those etc.

The data from Hiroshima and Nagasaki swamp the data from any other
sources and do include lots of low dose exposures. There is even one
case that tends to support the idea that low dose exposure can increase
resistance - one victim who moved from Hiroshima to Nagasaki and was
caught by both bombs. He received a low dose of radiation from the first
and a much higher, normally lethal, dose from the second but survived.

all of which involve acute doses.

And the areas with high levels of background radiation don't.

Correct. Those are chronic doses and the difference between acute and
chronic is an essential part of the argument against the data that lead
to applying the LNT model to all situations.

There is plenty of evidence that the LNT model is unreliable at
predicting the effects of low dose chronic exposure.

Yes, but hormesis is unproven anyway.

That is why it is described as a theory and not a law.

However, as it gives the most pessimistic predictions, it is likely to
continue to be used when setting safe exposure levels.

And that is the conservative approach that makes sense.

That depends whether you are setting occupational exposure levels in the
absence of accurate information or want to know what the actual effects
of radiation are.

That does not mean it is right.

Certainly people living in areas with naturally high background
levels of radiation do not exhibit anything like the amount of
cancer that the LNT model suggests.

But that may be due to other effects, because cancer incidence
does vary so widely due to all sorts of other effects too.

Certainly there may be variations due to other factors,

And we know that there are.
but the LNT model predicts that there should be a minimum number of
cases, irrespective of other factors, and they don't get anywhere near
that minimum number.

Yes, but I was JUST commenting on hormesis.

When there are two opposing theories, anything that disproves one
supports the other.

Colin Bignell

Nightjar wrote
Rod Speed wrote
Nightjar wrote
Rod Speed wrote
Nightjar wrote

This one goes into more detail about radiation hormesis:

http://www.angelfire.com/mo/radioadaptive/inthorm.html

That's still controversial and unproven
http://en.wikipedia.org/wiki/Hormesis#Controversy

It is unproven because it is very difficult to justify giving humans low
doses of radiation over long periods to build up the amount of data
needed to prove it.

That not how that sort of research is done.

That is what I said.

But you didn't say how it is done in that situation.

Its done by considering the epidemiology of what is seen with inevitable
variation in natural and unnatural radiation exposure that happens
anyway.

Its actually unproven because there are lots of other
factors that affect the incidence of even just cancer etc.

However, if an ethical committee were to approve a trial that involved
giving a very large number of humans controlled low dose chronic exposure
to radiation,

Not even possible.

it would eliminate most of the variables that make that approach so
unreliable.

Fraid not.

Not that an ethical committee would approve clinical trials on penicillin
if it applied current day standards.

They do just that, and rather more too.

Virtually all the data on the effects of radiation come from the bombing
of Japan and from nuclear accidents,

That's just plain wrong with the lower levels of radiation exposure.
The other obvious data is with areas which have much higher
than normal radiation levels, usually due to radioactivity in the
rocks in the area and to radioactive gases from those etc.

The data from Hiroshima and Nagasaki swamp the data from any other sources

Not with low level radiation they don't.

and do include lots of low dose exposures.

Nope, everyone there got very high levels of exposure.

There is even one case that tends to support the idea that low dose
exposure can increase resistance - one victim who moved from Hiroshima to
Nagasaki and was caught by both bombs. He received a low dose of radiation
from the first and a much higher, normally lethal, dose from the second
but survived.

The technical term for that is 'pathetically inadequate sample'

all of which involve acute doses.

And the areas with high levels of background radiation don't.

Correct. Those are chronic doses and the difference between acute and
chronic is an essential part of the argument against the data that lead to
applying the LNT model to all situations.

But that effect is, as I said, unproven.

There is plenty of evidence that the LNT model is unreliable at
predicting the effects of low dose chronic exposure.

Yes, but hormesis is unproven anyway.

That is why it is described as a theory and not a law.

That utterly mangles the real story on the use of those terms.

It's the theory of evolution, not the law of evolution.

It is very rigorously proven anyway.

Its completely trivial to prove that that's what happens experimentally
and we keep doing that all the time, most obviously with resistance etc.

And quite a few aspects of einstiens theorys have been proven too,
and they arent called laws because that has happened either.

However, as it gives the most pessimistic predictions, it is likely to
continue to be used when setting safe exposure levels.

And that is the conservative approach that makes sense.

That depends whether you are setting occupational exposure levels in the
absence of accurate information

And that is what 'setting safe exposure levels' is about.

or want to know what the actual effects of radiation are.

That isnt what 'setting safe exposure levels' is about.

That does not mean it is right.

Certainly people living in areas with naturally high background levels
of radiation do not exhibit anything like the amount of cancer that
the LNT model suggests.

But that may be due to other effects, because cancer incidence
does vary so widely due to all sorts of other effects too.

Certainly there may be variations due to other factors,

And we know that there are.

but the LNT model predicts that there should be a minimum number of
cases, irrespective of other factors, and they don't get anywhere near
that minimum number.

Yes, but I was JUST commenting on hormesis.

When there are two opposing theories,

There never are just two.

anything that disproves one supports the other.

That's just plain wrong too.

It can disprove both and show that neither are adequate explanations.

On Sun, 27 May 2012 15:40:31 +0100, Tim Streater
wrote:

In article ,
Peter Duncanson wrote:

On Sun, 27 May 2012 13:58:34 +0100, Tim Streater
wrote:

In article ,
Nightjar wrote:

On 08/05/2012 09:45, Rod Speed wrote:

Yes, but hormesis is unproven anyway.

That is why it is described as a theory and not a law.

You mean you described it as a hypothesis and not a theory.

A theory is a hypothesis for which there is sound solid repeatable
evidence. Usually a hypothesis is advanced to provide an explanatory
framework for existing observations, for which there is no or only
unsatisfactory explanations. To be any good, it has also to make
predictions that can then be tested. If the hypothesis makes successful
predictions, it gets advanced to the status of a theory.

Relativity and quantum theory are good examples of this. But note that
any scientific theory can be overturned if contrary evidence is found.

A scientific law can also be overturned if new evidence is found.

Newton's Laws of Motion were found not to be correct under some
circumstances. This lead to the Theories of Relativity.

That's just what I said.

Yes.

I added a few urls for the benefit of anyone (not you) who might
misunderstand the use in science of the words "theory", "hypothesis" and
"law". Those words do not have the same meaning in science as they do in
everyday chatter.

--
Peter Duncanson
(in uk.tech.digital-tv)

In article , Peter Duncanson
wrote:
On Sun, 27 May 2012 13:58:34 +0100, Tim Streater
wrote:


Relativity and quantum theory are good examples of this. But note that
any scientific theory can be overturned if contrary evidence is found.

A scientific law can also be overturned if new evidence is found.

Newton's Laws of Motion were found not to be correct under some
circumstances. This lead to the Theories of Relativity.

The terms 'Law' and 'Theory' do sometimes seem to be used as if one were
simply more well-established than the other. However there may be a subtle
distinction which can sometimes be made.

A 'Law' may be a statement that a given set of circumstances will produce a
specified outcome, based on a lot of examples giving consistent results. So
essentially a statement on an observational level about an effect from a
cause. Whereas a 'Theory' tends to imply or explicitly include some
underlaying wider 'explanation' (mechanism) about how the cause produces
the effect.

So you might have a 'Law' about what happens when you move a magnet near a
coil of wire to tell you how much voltage or current may arise. But a
'Theory' of Electromagnetism that 'explains' this in a wider context.

In reality, any such may well be provisional, and so either discarded as a
result of further experience, or modified, or the scope limited to being a
special case, or approximation. So the above theory may be seen differently
in another context. e.g. that magnetic fields may be an artifact of seeing
electric ones from another 4-space frame when looked at from the POV of
relativity.

Slainte,

Jim

--
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