Re: Contamination from I-131 in Perspiration

["J. Andrew Tompkins" <JATALBQ@ix.netcom.com>]

Milton E McLain wrote:
> 
> On Tue, 5 Aug 97 13:31:31 -0500 "Bass, Billy G." <bgb3@mhg.edu> writes:
> >
> >Ben,  we see considerable contamination in the sweat of I-131
> >patients. "   Etc., etc.
> 
> Be aware that thyroid ablation therapy patients may also emit significant
> quantities of I-131 via the  respiratory path.  In the Vet Medicine
> Clinic at Texas A&M we measured air concentrations of I-131 equal to the
> "old" MPC value in a kennel (dimensions: approx. 8 x 20 ft.) where
> treated cats were kept for a time before release to their owners.  The
> ventilation in this kennel space was only modest and the residual urine
> in the cage litter was doubtless a contributor to the airborne I-131 as
> the excreted I was oxidized by the air to volatile elemental, volatile
> iodine.  The total "cat inventory" of I-131 in that TAMU situation was
> estimated to be 25 mCi.
> 
> Milton McLain, Professor Emeritus
> mem6@juno.com

The residual urine should have been the primary contributor since
elememtal iodine is released from most acidic aqueous solutions, which
is why many radiochemical facilities keep their hot drain system sumps
on the alkaline side of the pH scale. 

It would be interesting to know what was the actual fraction from each
pathway.  It would also be interesting to do a study on iodine uptake by
spouses of patients treated with I-131.

Andrew Tompkins
ATL International, Inc.
Albuquerque, NM    87111


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