AW: [ RadSafe ] Excess relative risk

[John Jacobus]

One of the purposes of a skeptic is not so much to challenge as to present what is unknown.  
   
  I have been accussed of being silent.  I am not an epidemiologist, so I have to relie on those who are recognized experts. (If you choose to ignore the conclusion of experts, that is your choice.)   The consensus has been that there are no demonstracted effects below 100 mSv.  Neither harmful or beneficial.  All studies are individual pieces of a puzzle.  To date, the well-known epidemiologists have reached the conclusion stated above.  Individual studies may support your position or mine, but the concensus has always remained the same.   
   
  Your uncited comments below are interesting, but how do they fit in the overall study of radiation effects?  I have seen some studies that do show negative slopes.  We can all cherry pick the data that supports our positions, but what do the experts say?  
   
  

Rainer.Facius at dlr.de wrote:
  "Of course, there is no proof of negative excess risk."

John:

Your silence regarding several invitations to name/present what YOU consider the best proof of a positive excess relative risk for cancer also supports the reverse statement (with respect to your appraisal at least):

"Of course, there is no proof of positive excess risk." 

(for chronic low dose exposures up to around 600 mSv; for acute exposures such as the ATB survivors, peer reviewed published analyses demonstrate that even these data are compatible with 'no effect' up to about 200 mSv) 

By the way, you have been confronted here with data plots from half a dozen or so epidemiological studies of human (not to speak of animal laboratory experiments) cancer induction (lung cancer comes to my mind as well as the breast cancer incidence in babies which have been treated for hemangioma) which exhibit (sometimes marked) negative slopes in the initial dose region.

Part of the discrepancy appears to reside in what you are inclined to accept as 'proof'.

Kind regards, Rainer 

Dr. Rainer Facius
German Aerospace Center
Institute of Aerospace Medicine
Linder Hoehe
51147 Koeln
GERMANY
Voice: +49 2203 601 3147 or 3150
FAX: +49 2203 61970

-----Ursprüngliche Nachricht-----
Von: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] Im Auftrag von John Jacobus
Gesendet: Samstag, 26. Januar 2008 23:09
An: howard long; Otto G. Raabe; radsafe at radlab.nl
Betreff: Re: [ RadSafe ] Excess relative risk

Of course, there is no proof of negative excess risk. 


howard long wrote:
What would make clear in that formula that kD is a NEGATIVE excess relative risk when radiation exposure is under ~20cGy (rad), rapid rate, i.e. hormesis? +-kD?

Howard Long



+++++++++++++++++++
"If history teaches any lesson it is that no nation has an inherent right to greatness.  Greatness has to be earned and continually re-earned."
- Norman Augustine, Chairman of the National Academies Committee 

-- John
John Jacobus, MS
Certified Health Physicist
e-mail:  crispy_bird at yahoo.com
       
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