Re: Kerala Downs Syndrome

[rkathren@beta.tricity.wsu.edu (ronald kathren)]

Perhaps it would be useful to quote the brief albeit entire summary from
BEIR V, p. 385, re areas of high natural background:

        "In areas of high natural background radiation, an increased
frequency of chromosome aberrations has been noted repeatedly.  The
increases are consistent with those seen in radiation workers and in persons
exposed at high dose levels, although the magnitudes of the increases are
somewhat larget than predicted.  No increase in the frequency of cancer has
been documented in populations residing in areas of high natural backgroud
radiation."

I think the above says it all.  Clearly, increased chromosome aberrations
appear to be a biological effect associated with radiation exposure; whether
the effect is deliterious would seem to be open to question.  What does not
seem to be open to question is that there is in fact a biological effect
apparently associated with radiation exposure.

Ron Kathren    



>Ron,
> 
>> I hate to say it, but your argument sounds suspiciously like those of the
>> tobacco companies -- ie there has never been a case of lung cancer 'proven'
>> to have been caused by cigarette smoking.  As for people in high background
>> areas, the results of studies attempting to link their higher exposure with
>> morbidity or early mortality have proven, by and large, inconclusive,
>> because of a number of factors including the small size of the populations
>> involved.  However, in the Kerala State of India, an increased incidence of
>> Down's syndrome and chromosome aberrations has been reported.  
>
>I'm intrigued by the stretch that goes into trying to demonstrate effects in
>the face of much more substantial data that shows no or negative effects. Of
>dozens of endpoints in the enormous effort of detailed work over 20 years in
>Guangdong Province China, all the positive data (which show significant
>conflict with the linear model) are meticuluosly ignored and any tenuous
>implication takes on the mantle of implications, usually in my arena with
>unabased public fear-mongering. As a note on the Kerala India studies, the
>following is a summary extract from my report (which is widespread standard
>knowledge in the discussion and literature on low-level radiation health
>effects): 
>
>    "Nobel Laureate Dr. Rosalyn Yalow reports that in Kerala, India monazite 
>sands containing high thorium concentrations cause radiation exposures 
>4 times regional average concentrations. Detailed studies of the 12,918 
>people in the Kerala high background population was compared to a neighboring
>town with a control population of 5938. (Kochupillal, Nature, 1976) 
>
>There are no discenible health differences, except 12 cases of Down's
>syndrome found in the Kerala population, with none in the control population.
>However, Down's syndrome in India occurred at a rate of 1:1215 in 58,325 live
>births, which is statistically equivalent to (actually higher than) the rate
>in Kerala. The lack of Down's syndrome in the particular town used as a
>control 
>population is a statistical small-number aberration."
>
>>Similarly,
>> increased chromosome aberrations were observed in the Brazilian population
>> of Guarapari.  (Cf. BEIR V, pp. 383-385 for an excellen summary).
>
>"Increased chromosome aberrations" is another Gofman-ism used to instigate the 
>concerned public: another way of saying there are no health effects; don't
>report that many populations with many biological insults have "increased
>chromosome aberrations" with no biological relationship to any adverse effect. 
>High dose populations (eg, the UK high-dose worker group including the
>Windscale accident cleanup crew, and the Japanese Lucky Dragon fishermen
>exposed to the direct fallout of the Bikini atoll hydrogen bomb, have
>"chomosome aberrations" as "records" of their exposures, with no adverse
>health effects, but you are going to imply to the uninformed that the
>Guarapari population has deleterious effects from its high natural background
>dose exposure. I'm disappointed. 
>
>(I suppose no one knows how the US natural background work was cut off when
>the initial rigorous work showed no effect with significant statistics and
>tests of models and confounding factors (with _negative_ correlations). It
>takes the heroic personal efforts of Dr. Cohen to do some of the detailed work 
>that government and its agents suppressed (since 1973), which disproves the
>association of residential radon and lung cancer. But substantial evidence can 
>be dismissed and any anomolous positive indication made into a public fear
>generator on behalf of government agencies. What ever happened to science? 
>
>> Finally, if a priori you conclude that 50 mSv (5 rem) annually is basically
>> risk free, then why even study populations or people exposed at or below
>> this level?
>
>The existing data show the result despite efforts to suppress it. But this is
>disingenuous when the linear model is the "a priori" given while directly in
>conflict with the data (which gets no review and comment) while in many areas
>of investigation work is appropriate to confirm/validate the best current
>knowledge. 
>
>> Ron    
>
>Regards, Jim Muckerheide
>jmuckerheide@delphi.com
>
>