Re: Teeth/deer

[Franz Schoenhofer <schoenho@via.at>]

At 15:14 27.04.2000 -0500, you wrote:
>Ron makes some good points, especially his observation concerning the ratio 
>between Sr-90 and Sr-89.  
>
>Aarkrog has an interesting article concerning strontium-90 in shed deciduous 
>teeth collected in Denmark from children born 1950-1958.  HPJ 15(2):105-114, 
>1968
>
>Maybe, the tooth fairy project should have been the deer project.  Wild 
>animals (as biomonitors) may do a better job of reflecting trends in 
>environmental radiation concentrations.  Drs. Von Middlesworth (Iodine-131), 
>French (Sr-90), Bissell (Sr-90), Whicker and others have published some good 
>historical data.

The first teeth of children are investigated in order to have a result
representative of a relatively short time span. We have done extensive work
on Sr-90 in antlers of red deer, because we thought it would be a good
bioindicator, because antlers are built within relatively short time in
spring from scratch and therefore it should reflect the concentrations in
the environment. Unfortunately this is only partially true: Calcium (and
also Sr-90) is partially mobilized from the skeleton, because feed does not
contain enough calcium. In the skeleton there is of course an "average
concentration" over the life time of the animal. If we neglect that source
of probable error (we could not find any research on that question, which
we could have used for even rough estimations) we still end up with a
terrible lot of questions. The general pattern of a tremendous rise of
Sr-90 concentrations in the end of the fifties and the first years of the
sixties can easily be seen (as well as it can be seen in tritium and C-14
concentrations in the atmosphere), but after that time there are many
different patterns to be observed in the curves in different parts of
Austria. There is a change from direct fallout contamination of feed to
root uptake contamination. These two ways of the pathway to humans behave
totally different, much depending on the type of soil. 

To make it short: Though these animals definitely feed on local plants (on
the contrary children get their food from almost everywhere, but most
probably not from their living area), one cannot simply relate the
concentration in the antlers to the environment and to the fallout per
square meter.

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


Office:
Hofrat Dr. Franz Schoenhofer
Federal Ministry of Agriculture, Forestry, Environment and Water Management
Radiation Protection Department (BMLFUW I/8 U)
Radetzkystr. 2
A-1031 Vienna
AUSTRIA

phone: -43-1-71172-4458
fax: -43-1-7122331

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