Study of nasal swipe analysis methods at Los Alamos National Laboratory

The Health Physics Analysis Laboratory (HPAL) performs around 30,000 nasal swipe analyses for transuranic nuclides each year in support of worker health and safety at the Los Alamos National Laboratory (LANL). The analysis method used employs cotton swabs swiped inside a nostril and liquid scintillation analyses of the swabs. The technical basis of this method was developed at LANL and has been in use for over 10 years. Recently, questions regarding the usefulness of a non-homogeneous mixture in liquid scintillation analyses have created a need for re-evaluation of the method. A study of the validity of the method shows it provides reliable, stable, and useful data as an indicator of personnel contamination. The study has also provided insight into the underlying process which occurs to allow the analysis. Further review of this process has shown that similar results can be obtained with different sample matrices, using less material than the current analysis method. This reduction can save HPAL the cost of materials as well as greatly reduce the waste created. Radionuclides of concern include Am-241, Pu-239, and Pu-238