Pu, Am Retention

["Carbaugh, Eugene H" <gene.carbaugh@pnl.gov>]

The Pu and/or Am intake may be calculated from a fecal sample if you know the
mode of intake (e.g., inhalation, the elapsed time since the intake, and the
intake retention function (IRF) for feces at the time of sampling.  The
relationship is simple:  Intake = fecal excretion / IRF.  If you have multiple
bioassay data, or unknown times or mechanisms of intake,  the interpretation
gets muddy very quickly.  Values for the excretion function can be found in
NUREG-4844 (Interpretation of Bioassay Measurements), ICRP-54, or obtained using
computer codes such as CINDY, INDOS, REMEDY, or GENMOD-PC.  Another excellent
online source for you to examine is Chapter 5, Internal Dosimetry, of the DOE
Guide of Good Practices for Occupational Radiological Protection in Plutonium
Facilities  http://tis-nt.eh.doe.gov/wpphm/regs/pluton.pdf, (in particular, see
sections 5.7.3 and Table 5.6.  I recommend the whole chapter - there's a lot of
stuff compiled there.

Another good online source for internal dose information is the draft DOE
Standard for Internal Dosimetry, at
http://www.doe.gov/techstds/tsdrafts/saft0057.pdf  This document is still in
draft status but is excellent material.

You're welcome to contact me directly with any specific questions.  Plutonium
dosimetry is a large part of my job.

Gene Carbaugh
Internal Dosimetry
Radiation Protection Services
Pacific Northwest National Laboratory
gene.carbaugh@pnl.gov

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