AW: AW: [ RadSafe ] AW: Low level radiation and cancer:

[Rainer.Facius at dlr.de]

Christian:

Thank you for your information regarding the life expectancy in Kerala exceeding that of normal Indians by a huge 19 years. I wonder whether you might be able to dig up this information in writing. Nowadays TV stations often publish manuscripts of their broadcasts on their website. Since you did see this interview, you are the one predestined to search for such a document. 

Regarding your suggestion to study life expectancy as a function of the natural radiation exposure, my attitude is spilt. 

Given the never-ending hassles regarding the influence of confounders, competing - in particular socio-economic - factors etc., etc., I sincerely doubt that such a crude population wide measure will yield the convincing evidence you expect. That an endpoint even less specific than cancer could reveal a compelling association with background dose radiation which cancer studies - with the exception of B. Cohen's work for lung cancer - were so far unable to establish would appear as a miracle to me and many more. 

On the other hand, if indeed differences in the order of the Kerala life span excess could be demonstrated elsewhere and associated with radiation exposure, that really might be able to finally put LNT to rest. A far as science is concerned, I see the life expectancy of the LNT postulate approaching its natural demise anyway, so that to accelerate its departure might not be worth the efforts necessary for the studies which you suggest (of course Jim Muckerheide will vehemently object). If however such results could be construed as a case for radiation-hormesis working in human populations, the implications are hardly imaginable and of course would merit any effort. 

Hopefully you will be able to find that interview and share it.

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: Christian Hofmeyr [mailto:chris.hofmeyr at webmail.co.za] 
Gesendet: Freitag, 12. August 2005 14:36
An: Facius, Rainer
Cc: Bernard Cohen; radsafe at radlab.nl
Betreff: Re: AW: [ RadSafe ] AW: Low level radiation and cancer:

Rainer,
Thanks for your response.  I think we agree on important points.  What I wanted to emphasise is that the most sensitive direct test of LNT can be devised by its prediction regarding collective dose, probably in the framework of an ecological study.  I am very respectful of prof Cohen's work on radon (per implication based on collective lung dose) and his willingness to make his data available for scrutiny. However, as I tried to point out in a closing remark, there are IMO serious problems concerning particularly lung cancer, and I intend to comment more in due course.
In view of the claims of hormesis supporters (regarding health improvement through e.g. stimulation of the immune
system) and the challenge by John Jacobus, there might be value in considering longevity in areas with different background radiation levels, rather than focussing on cancer alone.  Life duration statistics are probably much more reliable than health (or cause of death) statistics in
many interesting places.   Put simply, this could
indirectly (per implication) provide answers concerning hormesis and even LNT, mindful of the collective dose prediction.  The necessary caveats apply.
I gathered from a recent BBC interview with a Nobel Prize-winning Indian economist that the 'traditional'
differential between India and China in average life expectancy was 14 years, 57 in India versus 71 in China.
  The exception was the Indian state of Kerala, where life expectancy was 76(!).  This was mentioned as an aside, in no particular context.  The interview was about favourable developments and had nothing to do with radiation. 
>From our perspective it would be relevant to know what percentage of the Kerala population lived in high radiation areas, and, particularly, how life expectancy varied between high and low radiation areas.  Parthasarathy pointed out to you that Krishnan Nair et al. (Radiation Research, 152, p145-148, 1999) preliminarily found no significant difference in cancer incidence, but I contend the life duration stats are bound to be more reliable.
Closer to home, the Swedes seem to have the highest life expectancy and the elevated background conditions are well known.  The statistics for parts of France and Germany should also be readily available.  It seems to be a question of collating available data.
Chris.Hofmeyr at webmail.co.za



On Thu, 11 Aug 2005 15:41:11 +0200
 <Rainer.Facius at dlr.de> wrote:
>Christian:
>
>Your comments by and large hit instead of being off the marks.
>
>Yet, in some cases it appears you make things more complicated than 
>necessary. E.g., in order to determine etc.
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