[ RadSafe ] LNT
Kai Kaletsch
eic at shaw.ca
Sun May 10 11:18:38 CDT 2009
Hi Al,
you wrote:
"If LNT is the generally accepted theory..." I think we have to look at what
"generally accepted" means. If I understand the LNT debate correctly, the
differing thoughts can be summarized like this:
1) Some people believe that LNT is a pretty good model and is no worse than
other models (hormesis/threshold). So, we might as well keep it.
2) Some people believe that LNT has significant shortcomings and is
probably not the correct scientific model, but it is easy and convenient to
use for making policy. So, we might as well keep it, as the basis for making
policy.
3) Some people believe that LNT is either incorrect or irrelevant at very
low doses and the use of LNT at very low doses should be restricted. See for
example the HPS position statement http://hps.org/documents/risk_ps010-1.pdf
, which explicitly states : " the Health Physics Society recommends against
quantitative estimation of health risks below an individual dose of 5 rem in
one year or a lifetime dose of 10 rem above that received from natural
sources."
4) Some people believe that there is strong evidence that LNT fails. Some of
these people think that it is time to adjust public policy accordingly.
Others think that this should be a scientific debate and public policy
should not be an issue.
While some of the politically appointed bodies still cling to 1), it seems
to be the minority position among scientists. The HPS states: "There is,
however, substantial scientific evidence that this model is an
oversimplification. It can be rejected for a number of specific cancers,
such as bone cancer and chronic lymphocytic leukemia, and heritable genetic
damage has not been observed in human studies. However, the effect of
biological mechanisms such as DNA repair, bystander effect, and adaptive
response on the induction of cancers and genetic mutations are not well
understood and are not accounted for by the linear, no-threshold model."
There used to be people who thought that LNT was actually a correct
description of the organism's response to radiation. This was before we knew
about biological mechanisms such as DNA repair, bystander effect, and
adaptive response. I have not heard any credible scientist state, in the
last 10 years, that he/she personally believes that LNT is the
scientifically correct model and that it describes the dose response 100%
correctly for all types of ionizing radiation.
It would be extremely easy to prove me wrong on this. All it would take is
for someone on this list to state that they personally believe that LNT is
the scientifically correct model that it describes the dose response 100%
correctly for all types of ionizing radiation.
It will be interesting to see if there is still anyone out there who truly
accepts LNT as a scientific theory.
Best Regards,
Kai
----- Original Message -----
From: <al at solidsurfacealliance.org>
To: <radsafe at radlab.nl>
Sent: Thursday, May 07, 2009 4:45 PM
Subject: [ RadSafe ] Re: radsafe Digest, Vol 196, Issue 3
"I listen with interest when people talk about hormesis
and/or thresholds, and await models and studies that would elevate one
of those concepts to the dominant paradigm status."
Excellent point and one that if logic rules the discussion, ends the
discussion. If LNT is the generally accepted theory, any claims to the
contrary have the burden of proof. If the BEIR committee changes their
position on LNT, I will be convinced. Prior to that, right or wrong, the
radiation is chocolate crowd will lack credibility.
Al
--- On Thu, 5/7/09, radsafe-request at radlab.nl <radsafe-request at radlab.nl>
wrote:
From: radsafe-request at radlab.nl <radsafe-request at radlab.nl>
Subject: radsafe Digest, Vol 196, Issue 3
To: radsafe at radlab.nl
Date: Thursday, May 7, 2009, 5:12 PM
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_______________________________________________
Today's Topics:
1. Re: Mr. Connell states basis for radon risk reduction
"havebeen rejected by legitimate scientists for decades"
(Steven Dapra)
2. LNT discussion and Mr. Connell (al at solidsurfacealliance.org)
3. Re: Mr. Connell states basis for radon risk reduction
"havebeen rejected by legitimate scientists for decades"
(Maury Siskel)
4. Update "Half Century of Health Physics" DVD (Demers, Joseph W)
5. RE: Update "Half Century of Health Physics" DVD (Bob Cherry)
6. RE: radiation risk (Tuttle, William K. (Portland))
7. RE: Mr. Connell states basis for radon riskreduction
"havebeen rejected by legitimate scientists for decades"
(Brennan, Mike (DOH))
8. Po-210 poisoning (Franz Sch?nhofer)
9. Lithium May Help Radiation Target Cancer, Spare Healthy
Tissue (Cary Renquist)
10. INPO Qualification Card for Engineers (Dave Biela)
11. Radiation Safety Technician Job (Dave Biela)
12. Food Irradiation TV Story (Joel C.)
13. Weapon of Choice: Depleted Uranium | CommonDreams.org
(Roger Helbig)
14. Nuclear Power Plants and Natural Hazards (Tony Harrison)
15. SAIC RSO position in Afghanistan (Mudek, Mario D.)
----------------------------------------------------------------------
Message: 1
Date: Tue, 05 May 2009 18:43:24 -0600
From: Steven Dapra <sjd at swcp.com>
Subject: Re: [ RadSafe ] Mr. Connell states basis for radon risk
reduction "havebeen rejected by legitimate scientists for decades"
To: radsafe at radlab.nl
Message-ID: <5.2.1.1.1.20090505184220.009f2530 at mail.swcp.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed
May 5
True enough. No one has made that claim. Is it possible to prove
that 250 pCi/L in a home *can* cause cancer? Or that it will? And for
what period of time must one be exposed to Rn at this level? Etc., etc. I
am not suggesting that anyone is making the claim that exposure in a home,
at this level, can cause cancer. I am merely asking an academic question,
to wit, can it be proven.
Steven Dapra
At 03:29 PM 5/5/09 -0400, you wrote:
>Brennan, Mike (DOH) wrote:
>>
>>While it is not a study, here is an article about a situation I was
>>slightly involved in:
>>http://www.spokesman.com/stories/2009/mar/08/a-silent-danger/. The woman
>>in the article is a never-smoker, living in and from non-smoking
>>households, and working in a smoke free workplace. She was diagnosed
>>with lung cancer. When her home was tested for radon the levels on the
>>main floor, including in her bedroom, were around 250 pCi/l. I am not a
>>radi-phobe, but that's a lot of radon. I acknowledge that we do not know
>>for certain what induced her cancer, but I know what I consider to be the
>>most likely suspect.
> No one has claimed that 250 pCi/L in a home cannot cause cancer
>
>--
>Bernard L. Cohen
>Physics Dept., University of Pittsburgh
>Pittsburgh, PA 15260
>Tel: (412)624-9245 Fax: (412)624-9163
>e-mail: blc at pitt.edu web site: http://www.phyast.pitt.edu/~blc
------------------------------
Message: 2
Date: Tue, 5 May 2009 17:45:54 -0700 (PDT)
From: al at solidsurfacealliance.org
Subject: [ RadSafe ] LNT discussion and Mr. Connell
To: radsafe at radlab.nl
Message-ID: <789473.40968.qm at web705.biz.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Thanks Mike, that is the problem with arguments like Mr. Connell uses, a bit
of truth used in misleading ways.
I think your description of LNT is right, there will be different thresholds
for everyone and near impossible to sort out. I personally can't see LNT
working down at near zero levels, so I adopted 4 to 5 times background
radiation level as my level of "safety", with the caveat of mentioning that
Oklahoma has low background radiation (3 to 6 uR/hr). That said, if I sell
someone a granite countertop that is at 15 uR/hr, I mention that some
believe there is a tiny risk so that a 5 uR/hr top would be a better choice.
Mr. Cohen,
I'm working my way through that paper you sent, thank you for sending it. I
do have one question, if BEIR VII is correct, how can both positions be
correct? As an outsider to the radiation safety community, it is difficult
to think of both positions as accurate. Until all this is sorted out, isn't
ALARA still the best way to go?
Al
------------------------------
Message: 3
Date: Wed, 06 May 2009 04:18:05 -0500
From: Maury Siskel <maurysis at peoplepc.com>
Subject: Re: [ RadSafe ] Mr. Connell states basis for radon risk
reduction "havebeen rejected by legitimate scientists for decades"
To: Steven Dapra <sjd at swcp.com>
Cc: radsafe at radlab.nl
Message-ID: <4A0155CD.1080300 at peoplepc.com>
Content-Type: text/plain; charset=us-ascii; format=flowed
It is difficult to follow this thread without some amusement. If memory
serves, there were intense and very informative disagreements on radsafe
about 12 years ago (among other periods). The archives would refresh
many of these data including vigorous efforts by Bill Field and others
-- it was complete with a mystery participant who refused to identify
themselves or their affiliation. My subjective recollection is that
Bernie Cohen's classic comprehensive work pretty well carried the day.
That research still stands, I think, untarnished to this day. In any
case, there remains a wealth of information and references in the
archives of that once upon a time in a land far away .... sigh ....
http://www.radlab.nl/radsafe/archives/
Best,
Maury&Dog [MaurySiskel maurysis at peoplepc.com]
==================================
Steven Dapra wrote:
> May 5
>
> True enough. No one has made that claim. Is it possible to
> prove that 250 pCi/L in a home *can* cause cancer? Or that it will?
> And for what period of time must one be exposed to Rn at this level?
> Etc., etc. I am not suggesting that anyone is making the claim that
> exposure in a home, at this level, can cause cancer. I am merely
> asking an academic question, to wit, can it be proven.
>
> Steven Dapra
> _______________________________
>
> At 03:29 PM 5/5/09 -0400, you wrote:
>
>> Brennan, Mike (DOH) wrote:
>>
>>> While it is not a study, here is an article about a situation I was
>>> slightly involved in:
>>> http://www.spokesman.com/stories/2009/mar/08/a-silent-danger/. The
>>> woman in the article is a never-smoker, living in and from
>>> non-smoking households, and working in a smoke free workplace. She
>>> was diagnosed with lung cancer. When her home was tested for radon
>>> the levels on the main floor, including in her bedroom, were around
>>> 250 pCi/l. I am not a radi-phobe, but that's a lot of radon. I
>>> acknowledge that we do not know for certain what induced her cancer,
>>> but I know what I consider to be the most likely suspect.
>>
> __________________________________
>
>> No one has claimed that 250 pCi/L in a home cannot cause cancer
>>
>> --
>> Bernard L. Cohen
>> Physics Dept., University of Pittsburgh
>> Pittsburgh, PA 15260
>> Tel: (412)624-9245 Fax: (412)624-9163
>> e-mail: blc at pitt.edu web site: http://www.phyast.pitt.edu/~blc
>
------------------------------
Message: 4
Date: Wed, 6 May 2009 09:26:29 -0700
From: "Demers, Joseph W" <Joseph_W_Demers at RL.gov>
Subject: [ RadSafe ] Update "Half Century of Health Physics" DVD
To: "'radsafe at radlab.nl'" <radsafe at radlab.nl>
Message-ID:
<F4561CBF4FBBF240BEF1370289612DDA609AB4C22E at EMDB01-1.rl.gov>
Content-Type: text/plain; charset="us-ascii"
First, thanks to all that replied either on line or directly to me.
Here is what I have found regarding the ability to run the subject program:
If you have an old install of XP (even SP3) without recent updates the
program will run. As to why this is and some possible avenues for folks more
Windows knowledgeable than I to think about see below.
According to the HP Journal folks, they are aware that the program does not
work under Vista. They had not heard of my XP problem. They aren't
supporting the program but are at the early stages of developing a follow on
product.
RadSafers results were mixed with about half able to run the program under
XP, usually with the caveat that the machine was older.
In looking around the net, the QLU program is legacy now, but appears to
have operated via HTTP protocol using a program called xserver.exe. My
suspicion is that updates to Win XP fixed a vulnerability that blocks port
8080 that xserver wants to use to communicate with QLU.
My fix was to dig out an old laptop that had not been updated in a while and
try the program. It worked so as long as I don't allow for updates it should
continue to do so. Please be aware if you try this approach that some
updates will make the program non-functional.
If the above sparks anyone to a better solution, please let me know.
Regards,
Joe DeMers, CHP, CSP
Health Physicist
509-376-0733
The contents of this message are mine personally and do not reflect the
views or position of the U.S. Department of Energy or the federal
government.
------------------------------
Message: 5
Date: Wed, 6 May 2009 11:59:50 -0500
From: "Bob Cherry" <bobcherry at satx.rr.com>
Subject: RE: [ RadSafe ] Update "Half Century of Health Physics" DVD
To: <radsafe at radlab.nl>
Message-ID: <004101c9ce6c$11bf0150$353d03f0$@rr.com>
Content-Type: text/plain; charset="us-ascii"
The new Microsoft Windows 7 due out in the fall will contain a virtual
version of Windows XP, so maybe the DVD will work with it.
http://www.computerworld.com/action/article.do?command=viewArticleBasic&arti
cleId=9132119&source=rss_news
After setup, it looks like running the DVD will be no problem.
Also, Vista can run a virtual PC into which you can load a copy of Windows
XP as the operating system.
http://www.microsoft.com/downloadS/details.aspx?FamilyID=04d26402-3199-48a3-
afa2-2dc0b40a73b6&displaylang=en
This is a more complicated workaround, but you might have fun trying it. I
use it to run RESRAD on my Vista computer.
Bob C
-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of Demers, Joseph W
Sent: Wednesday, May 06, 2009 11:26 AM
To: 'radsafe at radlab.nl'
Subject: [ RadSafe ] Update "Half Century of Health Physics" DVD
First, thanks to all that replied either on line or directly to me.
Here is what I have found regarding the ability to run the subject program:
If you have an old install of XP (even SP3) without recent updates the
program will run. As to why this is and some possible avenues for folks
more Windows knowledgeable than I to think about see below.
According to the HP Journal folks, they are aware that the program does not
work under Vista. They had not heard of my XP problem. They aren't
supporting the program but are at the early stages of developing a follow on
product.
RadSafers results were mixed with about half able to run the program under
XP, usually with the caveat that the machine was older.
In looking around the net, the QLU program is legacy now, but appears to
have operated via HTTP protocol using a program called xserver.exe. My
suspicion is that updates to Win XP fixed a vulnerability that blocks port
8080 that xserver wants to use to communicate with QLU.
My fix was to dig out an old laptop that had not been updated in a while and
try the program. It worked so as long as I don't allow for updates it
should continue to do so. Please be aware if you try this approach that
some updates will make the program non-functional.
If the above sparks anyone to a better solution, please let me know.
Regards,
Joe DeMers, CHP, CSP
Health Physicist
509-376-0733
The contents of this message are mine personally and do not reflect the
views or position of the U.S. Department of Energy or the federal
government.
_______________________________________________
You are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and understood the
RadSafe rules. These can be found at:
http://radlab.nl/radsafe/radsaferules.html
For information on how to subscribe or unsubscribe and other settings visit:
http://radlab.nl/radsafe/
------------------------------
Message: 6
Date: Tue, 5 May 2009 07:15:31 -0700
From: "Tuttle, William K. (Portland)" <William.Tuttle at va.gov>
Subject: RE: [ RadSafe ] radiation risk
To: "al gerhart" <webmaster at solidsurfacealliance.org>,
<radsafe at radlab.nl>
Message-ID:
<D0B27DE9CD2E6446AD9C65DC38E807B904F7191E at VHAV20MSGA1.v20.med.va.gov>
Content-Type: text/plain; charset="iso-8859-1"
Scientific concerns aside, risk statements for human subjects are to be
written at an 8th grade level-i.e. easily understood. This does not, in my
opinion, meet that criteria.
William K. Tuttle III, PhD
Radiation Safety Officer
Portland VA Medical Center
Any and all opinions expressed in this message are mine alone and do not
necessarily reflect those of the Portland VA Medical Center, The Department
of Veterans Affairs, or the United States Government.
This transmission is intended only for the use of the person or office to
which it is addressed and may contain information that is privileged,
confidential, or protected by law. All others are hereby notified that
receipt of this message does not waive any applicable privilege or exemption
from disclosure and that any dissemination, distribution, or copying of this
communication is prohibited. If you have received this communication in
error, please notify me immediately at the following telephone number:
503-220-8262, ext 55853. Thank you.
-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of al gerhart
Sent: Thursday, April 30, 2009 7:09 PM
To: radsafe at radlab.nl
Subject: [ RadSafe ] radiation risk
Could I get some comments on this statement? I don't think this person has
both oars in the water.
"The evidence for low-level carcinogenicity is virtually non-existent. "
Thanks,
Al
_______________________________________________
You are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and understood the
RadSafe rules. These can be found at:
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For information on how to subscribe or unsubscribe and other settings visit:
http://radlab.nl/radsafe/
------------------------------
Message: 7
Date: Wed, 6 May 2009 13:38:58 -0700
From: "Brennan, Mike (DOH)" <Mike.Brennan at DOH.WA.GOV>
Subject: RE: [ RadSafe ] Mr. Connell states basis for radon
riskreduction "havebeen rejected by legitimate scientists for decades"
To: <radsafe at radlab.nl>
Message-ID:
<37C41083D3480E4BBB478317773B845D0148EEFD at dohmxtum31.doh.wa.lcl>
Content-Type: text/plain; charset="us-ascii"
Hi, Steve.
Proving that something *will* cause a negative outcome is, of course,
impossible to do before the negative outcome has occurred, and sometime
even then it isn't accepted by all parties. I had an uncle who was
convinced that drinking did not effect his driving, and that no one
could prove differently. And, to be fair, he was never involved in a
serious collision that I know of. Still.
As I understand it, at the moment there is no way of demonstrating that
a particular cancer was caused by radiation (please note that this is
not my field, and I may be wrong about some cases. Also, new
developments might at any moment make it easy to do). I do, however,
understand and accept the model that predicts that some cells that are
exposed to radiation will become cancerous. I feel that is pretty well
established. I listen with interest when people talk about hormesis
and/or thresholds, and await models and studies that would elevate one
of those concepts to the dominant paradigm status.
-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On
Behalf Of Steven Dapra
Sent: Tuesday, May 05, 2009 5:43 PM
To: radsafe at radlab.nl
Subject: Re: [ RadSafe ] Mr. Connell states basis for radon
riskreduction "havebeen rejected by legitimate scientists for decades"
May 5
True enough. No one has made that claim. Is it possible to
prove that 250 pCi/L in a home *can* cause cancer? Or that it will?
And for what period of time must one be exposed to Rn at this level?
Etc., etc. I am not suggesting that anyone is making the claim that
exposure in a home, at this level, can cause cancer. I am merely asking
an academic question, to wit, can it be proven.
Steven Dapra
At 03:29 PM 5/5/09 -0400, you wrote:
>Brennan, Mike (DOH) wrote:
>>
>>While it is not a study, here is an article about a situation I was
>>slightly involved in:
>>http://www.spokesman.com/stories/2009/mar/08/a-silent-danger/. The
>>woman in the article is a never-smoker, living in and from non-smoking
>>households, and working in a smoke free workplace. She was diagnosed
>>with lung cancer. When her home was tested for radon the levels on
>>the main floor, including in her bedroom, were around 250 pCi/l. I am
>>not a radi-phobe, but that's a lot of radon. I acknowledge that we do
>>not know for certain what induced her cancer, but I know what I
>>consider to be the most likely suspect.
> No one has claimed that 250 pCi/L in a home cannot cause cancer
>
>--
>Bernard L. Cohen
>Physics Dept., University of Pittsburgh
>Pittsburgh, PA 15260
>Tel: (412)624-9245 Fax: (412)624-9163
>e-mail: blc at pitt.edu web site: http://www.phyast.pitt.edu/~blc
_______________________________________________
You are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and understood
the RadSafe rules. These can be found at:
http://radlab.nl/radsafe/radsaferules.html
For information on how to subscribe or unsubscribe and other settings
visit: http://radlab.nl/radsafe/
------------------------------
Message: 8
Date: Wed, 6 May 2009 22:45:26 +0200
From: Franz Sch?nhofer <franz.schoenhofer at chello.at>
Subject: [ RadSafe ] Po-210 poisoning
To: "RADSAFE" <radsafe at radlab.nl>, "RADCHEM-LIST \(RADCHEM-LIST\)"
<RADCH-L at in2p3.fr>
Message-ID: <D78E194F7BF5442980124B969794A755 at pc1>
Content-Type: text/plain; charset="iso-8859-1"
RADSAFErs,
Thank you for all your feedback on the Litvinenkow (Litwinenkow) poisoning.
Unfortunately I was very busy, so I have not been able to check all of them
yet, moreover I will go tomorrow to Poland and later to Hungary for radon
workshops. I hope to be able to give some summary after a few weeks.
Best regards,
Franz
Franz Schoenhofer, PhD
MinRat i.R.
Habicherg. 31/7
A-1160 Wien/Vienna
AUSTRIA
------------------------------
Message: 9
Date: Wed, 6 May 2009 13:53:42 -0700
From: "Cary Renquist" <cary.renquist at ezag.com>
Subject: [ RadSafe ] Lithium May Help Radiation Target Cancer, Spare
Healthy Tissue
To: <radsafe at radlab.nl>
Message-ID:
<C3973DA2E426594A8EC6DC90DB0540A003E56C22 at ipl-mail.ipl.isotopeproducts.com>
Content-Type: text/plain; charset="us-ascii"
They found that lithium did not prevent the generation of DSBs but
promoted a particular kind of DNA repair - called nonhomologous
end-joining (NHEJ) repair - which is the predominant repair mechanism
used by normal neurons. Xia and colleagues showed biochemical and
genetic evidence that radiation-induced DSBs were repaired with greater
efficiency in lithium-treated cells via the NHEJ pathway.
However, none of these effects were observed in malignant glioma (brain
tumor) cells, presumably because cancer cells generally utilize a
different DNA repair mechanism, Xia said.
<http://www.biosciencetechnology.com/ShowPR.aspx?PUBCODE=090&ACCT=900000
0100&ISSUE=0905&RELTYPE=RLSN&PRODCODE=00000000&PRODLETT=H&CommonCount=0>
Lithium May Help Radiation Target Cancer, Spare Healthy Tissue -
Bioscience Technology Online http://bit.ly/KIeEY
Lithium May Help Radiation Target Cancer, Spare Healthy Tissue
May 2009
Vanderbilt-Ingram Cancer Center investigators have uncovered a mechanism
that helps explain how lithium, a drug widely used to treat bipolar mood
disorder, also protects the brain from damage that occurs during
radiation treatments.
In the May 1 issue of the Journal of Clinical Investigation, Fen Xia,
MD, PhD, and colleagues show that lithium promotes DNA repair in healthy
cells but not in brain tumor cells. The findings suggest that lithium
treatment could offer a way to protect healthy brain tissue from damage
that may occur during cranial radiation treatments.
Cranial irradiation is part of standard therapy for both primary and
metastatic brain tumors. However, as with all treatment modalities,
radiation often causes long-term side effects. In particular,
neurological impairments - including lowered IQ, learning difficulties
and memory loss - have been reported, especially in children treated for
brain cancers. Radiation-induced damage to the healthy cells of the
hippocampus, a brain structure crucial for learning and memory, is one
likely source of these deficits.
These cognitive impairments have long-lasting effects on the quality of
life for survivors, noted Xia, an assistant professor of Radiation
Oncology and Cancer Biology.
"Because these patients can now survive longer and are being cured,
alleviating long-term toxicity is becoming more important," she said.
Researchers have been searching for agents that could protect healthy
brain tissue from radiation-induced damage. Previously,
Vanderbilt-Ingram investigators - led by Dennis Hallahan, MD, chair of
Radiation Oncology and the Ingram Professor of Cancer Research - found
that lithium treatment protects cultured hippocampal neurons from
radiation-induced cell death and improves cognitive performance in
irradiated mice.
But how lithium protects against radiation-induced damage is unclear.
Radiation kills tumor cells by damaging their DNA, but it can also
attack the DNA of healthy cells. One of the most serious types of DNA
damage is the chromosomal double-stranded break (DSB), in which both
strands of the double helix are severed. Even a single unrepaired DSB
can be lethal to a cell. Fortunately, the body has several different
ways to repair DNA damage.
Xia, whose lab studies the mechanisms of DNA repair in normal cells and
tumor cells, suspected that lithium might affect how DNA is repaired
following radiation-induced damage.
Working with Eddy Yang, MD, PhD, a resident in the Radiation Oncology
department and an American Board of Radiology Holman Research Scholar,
and postdoctoral research fellow Hong Wang, MD, PhD, Xia and colleagues
examined DNA repair in lithium-treated mouse hippocampal neurons exposed
to radiation.
They found that lithium did not prevent the generation of DSBs but
promoted a particular kind of DNA repair - called nonhomologous
end-joining (NHEJ) repair - which is the predominant repair mechanism
used by normal neurons. Xia and colleagues showed biochemical and
genetic evidence that radiation-induced DSBs were repaired with greater
efficiency in lithium-treated cells via the NHEJ pathway.
However, none of these effects were observed in malignant glioma (brain
tumor) cells, presumably because cancer cells generally utilize a
different DNA repair mechanism, Xia said.
The researchers confirmed these findings in mice treated with cranial
radiation. The results suggest that lithium protects healthy hippocampal
neurons by promoting NHEJ-mediated DNA repair - but that lithium offers
no protective effect in the brain tumor cells tested.
Since some tumors are resistant to radiation, Xia hopes that lithium
treatment could provide a way to increase the radiation dose to levels
that will kill the tumor cells while protecting healthy brain tissue.
The team is launching an investigation of the safety and feasibility of
lithium treatment in patients with low-grade glioma or brain metastases
from small cell lung cancer.
Release date: May 1, 2009
Source: Vanderbilt-Ingram Cancer Center
------------------------------
Message: 10
Date: Thu, 07 May 2009 12:06:01 -0400
From: "Dave Biela" <Dave.Biela at wves.org>
Subject: [ RadSafe ] INPO Qualification Card for Engineers
To: <radsafe at radlab.nl>
Message-ID: <sa02cea8.094 at mail.wvnsco.com>
Content-Type: text/plain; charset=US-ASCII
I am trying to find out information about INPO Qualification Cards for
Radiological Engineers. If you have any information about them can you
contact me at dave.biela at wves.org or 716-942-4423.
Thank You
David Biela
------------------------------
Message: 11
Date: Thu, 07 May 2009 12:18:11 -0400
From: "Dave Biela" <Dave.Biela at wves.org>
Subject: [ RadSafe ] Radiation Safety Technician Job
To: <radsafe at radlab.nl>
Cc: Mark Kolhagen <Mark.Kolhagen at wves.org>
Message-ID: <sa02d18e.057 at mail.wvnsco.com>
Content-Type: text/plain; charset=US-ASCII
Radiation Safety Technicians are needed at the West Valley Demonstration
Project in West Valley New York.
For information on pay and benefits contact mark.kolhagen at wves.org
860-951-1310.
------------------------------
Message: 12
Date: Thu, 07 May 2009 12:35:55 -0400
From: "Joel C." <cehn at aol.com>
Subject: [ RadSafe ] Food Irradiation TV Story
To: radsafe at radlab.nl
Message-ID: <8CB9D4906FBC10B-778-120 at webmail-md20.sysops.aol.com>
Content-Type: text/plain; charset="us-ascii"
I got this from ABC's 20/20:
"This Friday at 10 p.m. ET, I have another "20/20" special, "You Can't Even
Talk About It." We tackle touchy taboos, like:
...Food Irradiation.
I expect a well balanced story--this reporter often goes against the
"conventional wisdom".? FYI.
Joel I. Cehn, CHP
Oakland, California
joel at appliedsciencesco.com
------------------------------
Message: 13
Date: Thu, 7 May 2009 04:39:29 -0700
From: "Roger Helbig" <rhelbig at sfo.com>
Subject: [ RadSafe ] Weapon of Choice: Depleted Uranium |
CommonDreams.org
To: "Radsafe" <radsafe at radlab.nl>
Message-ID: <00c901c9cf08$8cbaf340$a630d9c0$@com>
Content-Type: text/plain; charset="US-ASCII"
http://www.commondreams.org/headline/2009/05/06-2#comment-1197745
Starting with the headline, this Common Dreams reposting from a Kansas City
area TV station's supposed I-team broadcast is full of false information - I
have directly corresponded with some of you, but I think that all should be
aware.
Roger Helbig
------------------------------
Message: 14
Date: Thu, 07 May 2009 07:24:49 -0600
From: "Tony Harrison" <laharris at smtpgate.dphe.state.co.us>
Subject: [ RadSafe ] Nuclear Power Plants and Natural Hazards
To: <radsafe at radlab.nl>
Message-ID: <4A028CC0.81EC.00E3.0 at cdphe.state.co.us>
Content-Type: text/plain; charset=UTF-8
>From another listserve:
Session announcement for the International Lithosphere Program (ILP)
joint
task force conference to be held in Clermont Ferrand, University
Blaise
Pascal, France from October 5-9, 2009.
Convenors of the meeting are Dr. Alessandro Tibaldi (University of
Milan,
Italy) and Dr. Benjamin Van Wyk de Vries (Magmas et Volcans,
University
Blaise Pascal, France)
We would like to invite interested researchers to submit abstracts for
presentation in the session on Nuclear Power Plants and Natural
Hazards.
A brief description of the session is written below. Convenors for
this
session are Dr. Alfredo Mahar Lagmay (University of the Philippines)
and
Dr. Derek Rust (University of Portsmouth, England).
Please send your abstracts to mlagmay at nigs.upd.edu.ph or
Derek.Rust at port.ac.uk
We have invited Antonio Godoy, Acting Section Head, IAEA/NSNI/ESS to
give
the Keynote presentation for this session.
NUCLEAR POWER PLANTS AND NATURAL HAZARDS:
Many nuclear power plant facilities in the world are built in areas
with
significant natural hazards. At the time when these facilities were
constructed, safety of the plant site was evaluated according to the
prevailing state of knowledge on volcanic, earthquake and other
external
hazards. Site selection and safety assessment were carried out
according
to local practices, many of which without the benefit of
internationally
accepted guidelines that set criteria and procedures for assessing
potential hazards. Over the past three decades, volcanology and
volcano-seismology has advanced considerably and much was learned
about
the assessment of hazards. The session on “Nuclear power plants and
natural hazards� seeks to discuss developments in the science of
volcanology, seismology and meteorology and its practical application
to
safety evaluation of nuclear facilities. Contributions that present
specific applications are most welcome.
Tony Harrison, MSPH
Colorado Dept. of Public Health & Environment
Laboratory Services Division
(303)692-3046
tony.harrison at state.co.us
------------------------------
Message: 15
Date: Thu, 7 May 2009 14:52:48 -0700
From: "Mudek, Mario D." <MARIO.D.MUDEK at saic.com>
Subject: [ RadSafe ] SAIC RSO position in Afghanistan
To: "Radsafe" <radsafe at radlab.nl>
Message-ID:
<36AD1A0A0D77124A8AC6A4F508C446EB36931D at 1655-its-exmp01.us.saic.com>
Content-Type: text/plain; charset="us-ascii"
This is through Aerotek, please follow the link to apply:
http://environmental.thingamajob.com/jobs/California/Radiation-Safety-Of
ficer/1922631
There will also be a Jr. HP Position that will float between Kuwait,
Qatar, Iraq and Afghanistan opening soon.
-m
Mario D. Mudek, RRPT
ARSO, Health Physicist Specialist
SAIC Radiation Safety Office
Notice: The information in this email may be confidential, proprietary
and/or privileged. This email is intended only for the individual or
organization named above, and not necessarily the addressee(s). If you
are not the intended recipient or an authorized representative of the
intended recipient, please do not read, copy or disseminate this email,
its attachments, or the information contained herein. If you have
received this email in error, please immediately notify the sender by
return email and delete this email from your system. Your assistance in
correcting this error is appreciated
------------------------------
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End of radsafe Digest, Vol 196, Issue 3
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