Re: Medical and/or University Bioassay Programs

[lambert@HAL.HAHNEMANN.EDU]

On Wed, 14 Feb 1996, Kathleen Hintenlang wrote:

> We are curious to know if anyone is performing routine bioassay for 
> anything other than iodine and tritium, and if not, how do they 
> justify not doing it?  (For example how do you justify that a 
> nuc med tech's uptake of technetium, gallium, thallium, indium etc or 
> a researcher using P-32 etc is less than the 10% ALI.)

Here goes my logic (or rationalization):

Bioassays for iodine are performed because if its volatility, and because
it concentrates in a radiosensitive organ.  Bioassays for tritium are
performed because it is volatile when in the form of HTO, because most
uses of HTO involve tens of millicuries, and because it is not easily
detected with portable survey instrumentation.  I don't think bioassays
for tritium are necessary in the few millicurie range when it is 
incorporated in non-volatile compounds (e.g., tritiated thymidine).  

I feel that if there was evidence of uptake then bioassays should be
performed.  The evidence that I look for is contamination around the entry
point of the material.  E.g., contaminated needle stick, contamination
around the mouth or nose, ...  Of course one must eliminate the
possibility of radioactive gases for this logic to work. 

One should keep in mind that a microcurie of an electron emitter delivers
a much smaller dose when it is in the body that it does when it is on the
the skin.  And skin contamination is much more likely than an uptake. 
Therefore, the most critical concern has to be skin contamination. 

Kent Lambert, CHP
LAMBERT@hal.hahnemann.edu

These are my thoughts.  If they are wrong
I accidentally pressed the send instead of
the delete key.  My employer makes no claim
to endorse my opinions.