Quality Control
Samples for
the Radiological Determinations of
Tritium, Americium, and Uranium in Urine*
Peter
C. Lindahl, Nancy L. Koski, George H. Brooks, Jr., Steven J. Goldstein,
Claudine E. Armenta, Edward R. Gonzales, Bret L. Lockhart, Nancy Lujan, Anthony
J. Sanchez
Analytical
Chemistry Sciences Group
Chemistry Division, Los Alamos National Laboratory
The Analytical Chemistry Sciences Group in the Chemistry
Division at Los Alamos National Laboratory provides inorganic, organic, and
radiological analytical laboratory and technical support in the areas of
environmental, waste management, industrial hygiene, and biological analysis. In
the biological analysis arena the Group performs analysis on a number of
different types of biological matrices including urine and fecal material. Americium-241; uranium isotopes-234, 235,
and 238; and tritium are determined in urine; and Am-241, U-isotopes, and
Pu-238 in fecal material. The Am, Pu,
and U are determined using radiochemical separation techniques followed by
alpha spectrometry; while tritium is determined by liquid scintillation.
In support of its analytical operations the Analytical
Chemistry Sciences Group maintains an ongoing quality control (QC) program as
part of its quality assurance (QA) program.
The overall QC program includes participation in both internal and
external performance evaluation programs.
The internal QC program includes in-house preparation of QC materials,
incorporation of blind QC and laboratory control samples into analysis batches,
and assessment of QC sample results. In
the biological analysis area, the preparation, distribution, and assessment of
urine QC samples has been developed and implemented for routine bioassay
analysis operations. A parallel scheme
for fecal material QC samples has not been established.
The presentation will describe the preparation of the
urine QC samples, integration and incorporation of the blind QC and laboratory
control samples into the analysis scheme, and the monitoring, assessment, and
use of QC sample results as part of the continuous improvement process for our
analytical services operations.
* This work is not being conducted in support of the LANL radiobioassay monitoring program.