Re: info

[stabin@esper.com (Mike Stabin)]

>We are examining the possibility of replacing a 24 hour composite urine
>sample with a single grab sample for plutonium bioassay.  Can a single
>grab sample at one point during the day be scaled up to a full day?  Does
>anyone use this value to determine body burden?  Physicians scale urine
>sample results by the creatinine level.  Can we also use creatinine?  Does
>plutonium excretion follow a diurnal cycle that would make one void,
>perhaps the first morning, more representative of the entire day?????
>
>-- 

Well, everyone, for any nuclide, scales up partial day samples to simulated
24-hr values, using either urine volume (and an assumed volume for the
individual, either standard - 1000/1400 ml/day for females/males - or
perhaps typical values for the individual) or creatinine.  I don't have
specific experience with Pu, but in general, there is much variability in
the excretion of radionuclides throughout the day, so I always recommend
that people use true 24-hr samples where possible with the 24-hr IRFs that
are available.  There is also the "last at night first in the morning"
simulated 24-hr sample that Kathren and others published a short article
about recently.  I don't have the reference handy, but I can get it if Ron
doesn't post it here himself.  The bottom line, IMO, is that it can
certainly be done but that true 24 hr is best.

Mike Stabin
Oak Ridge