RE: Cool Fact: Radioactive People

[Franz Schoenhofer <schoenho@via.at>]

At 12:45 17.12.1999 -0600, you wrote:


>> UNSCEAR gives world-population-average data that are significantly lower,
>> both for dose from natural radiation and for dose of anthropogenic
>> (largely medical) origin.  I believe the referred-to data cited have been
>> taken from NCRP reports that apply only to the population of the U.S.A.
>> The chief difference between natural dose for Americans (cited by NCRP)
>> and the world average (cited by UNSCEAR) is attributable to the difference
>> in the estimated doses from radon progeny.  I haven't looked lately, but I
>> believe this difference is about 0.8 mSv/y.
>> 
>> Bruce Heinmiller CHP
>> heinmillerb@aecl.ca
>> 
>> 	----------
>> 	From: 	Zack Clayton[SMTP:zack.clayton@epa.state.oh.us]
>> 	Reply To: 	radsafe@romulus.ehs.uiuc.edu
>> 	Sent: 	Friday, December 17, 1999 11:58 AM
>> 	To: 	Multiple recipients of list
>> 	Subject: 	RE: Cool Fact: Radioactive People
>> 
>> 	Regarding this statement:
>> 
>> 	One is that "Americans" should be substituted for "humans" below,
>> for the 3-
>> 	to 4-mSv dose to be substantiated.
>> 
>> 	Does this imply that Americans have a different value for internal
>> potassium from other North Americans/ Countries?  Or, that nobody else has
>> been bothered enough by this to measure their internal dose?   
>> 

I feel confused by these statements. I do not understand the difference
between "Americans" and "humans" - is there any? How can one construct a
difference between "Americans" and (obviously) "others" by comparing data
from NCRP reports and from UNSCEAR? All these data are so uncertain that a
difference of 0.8 mSv/y is in my opinion much smaller than the 1 sigma
uncertainty. The data are clearly estimates - who knows about the doses
from radon progeny in developing countries? Even in developed countries it
is extremely uncertain to postulate a mean value. The internal dose due to
K-40 will clearly depend on the persons - K-40 is present mostly in muscles
and malnutrition will certainly reduce the K-40 dose, as well as lack of
physical exercise, because K-40 is not present in fat tissue. Therefore
indeed there must be a difference of K-40 content in different population
groups. By the way, the internal dose from K-40 cannot be measured (how?),
but only calculated from whole body counting. 

Doses from medical application of x-rays and radioisotopes  m u s t
clearly be different between highly developed and underdeveloped countries. 

There are also geographical differences: The Northern Hemisphere had much
more fallout from nuclear bomb tests than the Southern Hemisphere. A few
European countries had much higher contamination from the Chernobyl
accident than others, not to talk about remote countries like the USA. But
the contribution has come outside the vicinity of the Chernobyl NPP to
hardly (or not) detectable values. This implies that there is also a time
variation. 

This is a probably much too detailed discussion, because the starting point
was "Cool Fact: Radioactive People". I have not checked the links, but what
I read from Andrews mail is encouraging. There seem to be some people who
have a realistic view on radioactivity. Isn't that great? We should be
happy about them. Anyway, what is the impact of a difference of 0.8 mSv/y -
does it make any difference? We should not give the anti's the argument
that scientists disagree about the impact of natural sources and medical
sources to doses!

Regards,

Franz


Franz Schoenhofer
Habicherg. 31/7
A-1160 Vienna
Austria
Tel.: +43-1-495 53 08
Fax.: same number
mobile phone: +43-664-338 0 333
e-mail: schoenho@via.at

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