[ RadSafe ] for: Brant Ulsh

[Demetrios Okkalides]

Brant, 

 

Thanks for the message. Your private e-mail does not seem to work. So I am publishing my answer to the list. I hope this is not an inconvenience to the rest. Here it is:



 I do not think it is a matter of authority or agreement. The request for a negative proof is an impossible task. This is easily demonstrated as follows: 

If, in order to use Low Dose - Low Rate radiation, there is a legitimate obligation to prove that  it does NOT have adverse effects, then such an obligation should result to a consensus. It must be extended to anyone’s idea of an adverse effect. I.e, that it does not cause:

 

a) rabies 

b) hair growth

c) smallpox

d) inflation

e) Down syndrome

f) cancer

g) divorce,  

h) adverse effects on cancer growth (i.e. diminishes cancer)

.

.

etc.

 

until such a list is exhausted.  Since this will clearly never happen, it must be concluded that such a request can not be a criterion to decide the use of LD-LR radiation. Hence a different criterion must be found.







Demetrios



  ----- Original Message ----- 
  From: Brant UIsh 
  To: jjc105 at yahoo.com ; od at tlmq.com 
  Sent: Friday, October 21, 2011 6:44 PM
  Subject: Your RADSAFE posts


  Jerry and Demetrios:
  You recently posted the messages below on RADSAFE.  I am a regular reader on the mailing list, however I chose not to post but rather communicate privately on intriguing messages.  Here are the messages that caught my interest:
   
  Message: 7
  Date: Thu, 20 Oct 2011 23:15:05 +0300
  From: "Demetrios Okkalides" <od at tlmq.com>
  Subject: Re: [ RadSafe ] Is there a threshold for radiation effects?
  To: "Jerry Cohen" <jjcohen at prodigy.net>,  "The International Radiation
        Protection \(Health Physics\) MailingList"
        <radsafe at health.phys.iit.edu>
  Message-ID: <9265E1FB7E1A47C99C989122C21D8A03 at lp>
  Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original
   
  I quite agree with you. My qualitative impression from many years of 
  hospital work is that indeed the LNT assumption is seriously flawed. 
  However, it seems to me that it is not my (our?) obligation to prove that no 
  adverse effects exist at low dose-low rate exposures. It should be the 
  obligation of the LNT's advocates to prove the opposite.
   
   
  D.Okkalides
  THEAGENEION Anticancer Hospital
  Thessaloniki
  Greece
   
  ----- Forwarded Message ----
  From: Jerry Cohen <jjc105 at yahoo.com>
  To: Demetrios Okkalides <od at tlmq.com>
  Sent: Thu, October 20, 2011 2:04:54 PM
  Subject: Re: [ RadSafe ] Is there a threshold for radiation effects?
   
   
  And, I agree with you. The problem is that it would be impossible to prove no 
  effects at very low doses, since you cannot prove a negative . The 
  counter-argument is that  very low dose effects, if any, could not be 
  statistically discernible, but that doesn't prove that they don't exist.
  jerry cohen
   
   
  I have been researching and discussing biological effect of low doses of radiation for years.  Here are some points for your consideration:
  1)      Demetrios -  the point you made is critical.  The null hypothesis is “no effect”.  The burden of proof is on the alternative hypothesis – in this case LNT.  If we were talking about hormesis, supralinearity, linear-quadratic, or any other alternative hypothesis, the burden of proof would be on whatever alternative we were testing.  If the evidence is insufficient to reject the null (no effect), in favor of one or more of the alternatives, then the null stands and we conclude that the evidence is insufficient to demonstrate an effect.  The take-home message here is that a threshold dose-response model is the null (since pretty much everybody agrees that radiation has been shown to cause adverse effects at high doses/dose-rates).  There must be sufficient evidence to demonstrate an effect, otherwise we cannot correctly assert that there is one.
  2)      Jerry -  you are quite correct that the counter-argument that LNT advocates frequently make is that we cannot say there is no effect just because the evidence is insufficient to show one.  They are right – we should not assert that “there is no effect”, but rather we should say, “if there is an effect, positive or negative, it is too small to detect by methods currently available”.  One can always argue that the effect is there, it is just too small to detect. Therefore, our radiation protection policy just assumes that there is a negative effect at resulting from small doses.  Unfortunately, by assuming an effect in the absence of evidence, and then demanding that proof of no effect be provided, they are committing a classical logical fallacy known formally as argumentum ad ignorantiam, and more commonly as “shifting the burden of proof” or “proving a negative”.  The attached article describes this logical fallacy quite clearly.  I am constantly dismayed by how few people recognize this fundamental abuse of the scientific method and passively accept the expenditure of significant resources demanded by a logically fallacious regulatory philosophy.
  Thank you for your thought-provoking RADSAFE posts.
   
  Best Regards,
  Brant Ulsh, PhD, CHP