Single Void Pu Urine Samples, etc.

[eh_carbaugh@ccmail.pnl.gov]

     The real problem with the suggestion to find a group of people with 
     stable Pu excretion and due a study of normalizing is that very few 
     people are excreting enough Pu to be detectable in a single void 
     sample.  Most of the I(orU)PPU club and other similar individuals are 
     detectable in 24-hour large volume samples but only at levels slightly 
     above the MDAs.  When you figure that a single void represents only 
     about 1/10 or so of the total excretion, the likelihood of that 
     quantity being detectable in routine, state-of-the-art, radiochemical 
     urinalysis procedures is very slim --- generally nil.  That's the 
     whole point of my original statement that it is a poor practice to try 
     to use single void Pu urine samples for routine bioassay.  If you were 
     to see something detectable in one and extrapolated it to a daily 
     volume, you would probably be at an intake of several ALIs.
     
     Single void samples are extremely valuable as special samples obtained 
     immediately following suspected intakes, or as an indication of the 
     effectiveness of DTPA chelation therapy for dose reduction following 
     transuranic intake.  But the issue in these applications is really the 
     need to start of continue therapy as opposed to accurate dose 
     estimates.
     
     I did attempt to get funding from a couple of sources a few years ago 
     for a special study of normalizing Pu urine based on different 
     parameters.  Unfortunately, no one was willing to fund it.  In these 
     times of tight money, declining budgets, and declining programs I have 
     no real hope that anyone will sponsor such a study.
     
        Gene Carbaugh
        Internal Dosimetry
        Pacific Northwest National Lab
        eh_carbaugh@pnl.gov