An interlaboratory comparison of dosimetry for a multi-institutional radiobiological research project: Observations, problems, solutions and lessons learned

Abstract

Purpose: An interlaboratory comparison of radiation dosimetry was conducted to determine the accuracy of doses being used experimentally for animal exposures within a large multi-institutional research project. The background and approach to this effort are described and discussed in terms of basic findings, problems and solutions.

Methods: Dosimetry tests were carried out utilizing optically stimulated luminescence (OSL) dosimeters embedded midline into mouse carcasses and thermal luminescence dosimeters (TLD) embedded midline into acrylic phantoms.

Results: The effort demonstrated that the majority (4/7) of the laboratories was able to deliver sufficiently accurate exposures having maximum dosing errors of ≤5%. Comparable rates of ‘dosimetric compliance’ were noted between OSL- and TLD-based tests. Data analysis showed a highly linear relationship between ‘measured’ and ‘target’ doses, with errors falling largely between 0 and 20%. Outliers were most notable for OSL-based tests, while multiple tests by ‘non-compliant’ laboratories using orthovoltage X-rays contributed heavily to the wide variation in dosing errors.

Conclusions: For the dosimetrically non-compliant laboratories, the relatively high rates of dosing errors were problematic, potentially compromising the quality of ongoing radiobiological research. This dosimetry effort proved to be instructive in establishing rigorous reviews of basic dosimetry protocols ensuring that dosing errors were minimized.

Keywords:

• Dosimetry
• ionizing
• radiation
• OSL/TLD dosimeters
• dose-response curve
• haematology
• animal models

Acknowledgements

The authors would like to thank the following individuals for their assistance, guidance and discussions in various phases of this work: Dr Vitaly Nagy, Dosimetry Group, US Armed Forces Radiobiology Research Institute of the Uniform Services University, Bethesda, MD; Dr Terry Yoshizumi, Radiation Dosimetry Laboratory, Medical Center, Duke University, Durham, NC; Dr Wendell Lutz, University of Arizona, Tucson, AZ; Ms Lauren Young, Memorial Sloan Kettering Cancer Center, New York, NY; Drs Mirela Kir, Mark Akselrod, and Mr Luke Carr, Dosimetry Laboratory, Landauer Inc., Glenwood, IL, USA.

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.

This work was supported by a National Institute of Allergy and Infectious Disease/National Institutes of Health contract (No. HHSN272200900059C) to the Radiation Effects Research Foundation, Hiroshima, Japan.