Plutonium detection levels in Urinalysis

[mail15077@pop.net]

Good Afternoon,

I have been doing some review of "historical" Plutonium bioassay results on 
workers.  Occasionally, one will see a bioassay result that appears to be just 
above the LLD, but seems anomalously high as it does not fit any Plutonium 
model very well.  While I suspect that these may be false positives (as I've 
been told the Pu analysis has a very sloppy low end), I cannot find any readily 
available information to support or refute that position.

I would appreciate any of you who have some expertise in Pu bioassay to comment 
on the following.  References would be appreciated.

1)  What are the common methods for analyzing for Pu in urine?

2)  For each of these methods, what would be a typical range of LLDs?

3)  Several LLDs I've seen in vendor literature discusses "XXX +/- 50%."  This 
does not impress me as being a very reliable low end.  Is there a thumb rule 
that establishes when a bioassay sample, although above the LLD, is probably a 
false positive.  At what factor of LLD should one start to treat the bioassay 
sample as reliable, and not a "false positive."

Jim Barnes, CHP
RSO
Boeing North American (formerly Rocketdyne Division, Rockwell International)




--UAA27535.839032153/fw.orau.gov--