Technical basis for using nose swab bioassay data for early internal dose assessment

Area of Science:

• Occupational health and safety
• Radiation protection
• Radiological dose assessment

Background:

• Early radionuclide intake estimation is crucial for managing inhalation incidents in the workplace.
• In vivo counting lacks sensitivity for certain radionuclides like Plutonium (Pu).
• Nasal airway passage measurements offer an alternative detection method.

Purpose of the Study:

• To evaluate the efficacy of nose swabs for early dose assessment of radionuclide inhalation.
• To analyze over 15 years of nose swab data from Los Alamos National Laboratory (LANL).
• To compare nose swab results with dose assessments derived from established Bayesian methods.

Main Methods:

• Routine use of nose swabs from the ET1 region for airborne Plutonium (Pu) releases and other radionuclides.
• Analysis of a 15-year dataset of nose swab measurements.
• Comparison of empirical nose swab data with dose assessments calculated using LANL's Bayesian methods.

Main Results:

• Nose swab data provide empirical support for early dose assessments following inhalation incidents.
• A rule of thumb dose factor of 0.8 mSv Bq(-1) was identified for Pu, assuming a linear relationship.
• The derived dose factor is specific to LANL's methods and models.

Conclusions:

• Nose swab analysis is a validated technique for rapid, preliminary dose assessments in occupational settings.
• This method aids occupational physicians and radiation protection personnel in immediate response to inhalation exposures.
• Caution is advised when applying LANL-specific dose factors to other facilities due to potential methodological differences.