RE: I-131 therapy capsules

[carol marcus <csmarcus@ucla.edu>]

At 11:20 AM 4/20/00 -0500, you wrote:
>At this institution we have not routinely used oral solution for I-131
>therapeutic doses for a long time (> 15 yrs?), but once in a while it is
>given in that form for special cases. e.g. patients who have difficulty
>swallowing capsules or who have a malabsorption problem. Officially, our
>procedures require that we do regular thyroid bioassays on the nurses who
>care for in-patients tyreated with I-131 and on others who perform
>radioiodinations. Unofficially, we also check the thyroids of the nuclear
>medicine techs quarterly. We have had only one positive assay and that was
>back in the 80's. The thyroid uptake was less than 0.1 mCi, and it was due
>to handling a contaminated label on a capsule vial. See Health
>Physics49:81-83(1985). Years ago at another institution the solution form
>was used routinely, and since I gave virtually all the doses (up to 300
>mCi), I would have my thyroid checked 24 hrs after each one. That was
>probably a license condition, but at this point in time I am not absolutely
>certain.
>
>David L. North, Sc.M. DABR
>Associate Physicist
>Department of Medical Physics
>Rhode Island Hospital
>593 Eddy St.
>Providence, RI 02903
>ph: (401)444-5961
>fax: (401)444-4446
>dnorth@lifespan.org
>
>> ----------
>> From: 	Debby Steva
>> Reply To: 	radsafe@romulus.ehs.uiuc.edu
>> Sent: 	Wednesday, April 19, 2000 15:16
>> To: 	Multiple recipients of list
>> Subject: 	I-131 therapy capsules
>> 
>> To all you nuc. med hospital types who previously used oral solution
>> I-131 but now use I-131 capsules for therapy doses - how have your
>> thyroid bioassay requirements (for personnel administering) changed (if
>> they have) and what are they currently?
>> 
>> Thanks,
>> 
>> D. Steva
>> University of Virgina
>> 
>> ************************************************************************
>> The RADSAFE Frequently Asked Questions list, archives and subscription
>> information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>> 
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>

Dear Radsafers:

Back in the middle to late 1980's, I-131 NaI from Syncor was NOT stabilized
against volatility because NRC FORBID THE PHARMACISTS TO STABILIZE THE CIS
PRODUCT.  This was finally changed when the nuclear medicine community wrote
a petition to the NRC and when Chairman Carr was told that it was going to
be stabilized immediately, even before the petition went through (that took
5 years of warfare), or we would go to the EPA and report him for causing
the most dangerous environmental hazard that had ever occurred in nuclear
medicine.

As to Iodide-I-131 used for iodinations, this material is NOT stabilized
against volatility, and bioassays therefore are sensible.  

Ciao, Carol

Carol S. Marcus, Ph.D., M.D.
Harbor-UCLA REI
<csmarcus@ucla.edu>

************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html