Re: RSO Inc. / Tritium Bio Accumulation

[Lester.Slaback@nist.gov]

>you drank was D2O.  It is difficult to get any accumulation of HTO, since
>the biological half-life of water in the body is fairly short - just a
>few days as I recall.

>The tritium in labeled compounds, such as amino acids, tends to be fairly
>labile and it will exchange 
> readily with the normal hydrogen in water.  Thus an aqueous solution of
>tritiated thymidine, for example, will eventually produce some HTO in the
>solvent water.  I do not know the equilibrium
>constant for this exchange reaction, but its possibility should be
>considered. 

These and other comments relate to the effective half-life of the specific
chemical form of the tritium.  Certainly in the case of HTO it behaves
like water, accumulates and exchanges with water in the organism, and is
excreted like water.  And because the tritium is highly diluted in the
natural environment with the non-radioactive form the organism cannot
'accumulate' the radioactive species like it can for other nuclides where
one does not  have this large isotopic dilution.

But in fact tritiated compounds do have slight physical and chemical
differences from their hydogenous compunds.  While we (i.e., people) have
to work hard to take advantage of these effects to accomplish enrichment I
think the original underlying question was - have any such enrichment
effects been observed in nature (or in a lab quasi-natural setting)?

I do not recall such, but perhaps others might.
-- 
the above are the personal musing of the author,
and do not represent any past, current, or future
position of NIST, the U.S. Government, or anyone else
who might think that they are in a position of authority.
NBSR Health Physics
NIST
Gaithersburg, MD 20899
301 975-5810
-----------------------------------------------------------
Lester.Slaback@nist.gov
-----------------------------------------------------------