[ RadSafe ] LSC for nasal swabs

[Franz Schönhofer]

William,

You mention an interesting potential application of LSC. I cannot give you
an answer for your problem, but I would like to emphasize that this would be
no easy task.

First of all, it is not clear, which alphas you are looking for, secondly
what are the concentrations you look for? In most cases "Liquid
Scintillation Spectrometry" deals with radionuclides, which are dissolved in
an appropriate matrix, Aerosols of for instance uranium oxide or plutonium
oxide cannot be dissolved in an LS cocktail. I know very well, that beta
emitters like Sr-90 (and Y-90) can be measured, when they are present in
form of a coprecipitate for instance with Sr-sulfate, but I have very little
experience with alpha-emitters. After chemical separation and careful
coprecipitation with e.g. neodymium fluoride they can be measured, showing
peaks (rather "hills") much inferior to surface barrier detector
alpha-spectrometry.

Another "caveat" is sure the presence of natural radionuclides from the
chain of progeny of radon and thoron. It is more than obvious that
alpha-emitting radionuclides from these decay chains will be deposited in
the nose.

Though I am an LSC-fan, who worked for more than 30 years in this field, I
think that in this case alpha spectrometry would be more appropriate.

So much my two Euro-Cents. If you find a solution I would be interested to
hear from you!

Best regards,

Franz
2008/11/18 Lee, William <LEEWS at nv.doe.gov>

> I'm looking for information on acceptable efficiency for nasal swabs
> counted via LSC. The activity of interest is alpha; I am led to believe
> that a number of sites around the DOE complex count for alpha activity
> using open window with no quench. Anyone have any specific experience
> using this approach? Contact off-line would be appreciated. Thanks.
>
>
>
> William S. Lee
>
> Nevada Test Site, NSTec, 295-4248
>
> leews at nv.doe.gov
>
> _______________________________________________
> You are currently subscribed to the RadSafe mailing list
>
> Before posting a message to RadSafe be sure to have read and understood the
> RadSafe rules. These can be found at:
> http://radlab.nl/radsafe/radsaferules.html
>
> For information on how to subscribe or unsubscribe and other settings
> visit: http://radlab.nl/radsafe/
>