Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans : joint RENEB and EURADOS inter-laboratory comparisons

Purpose: RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation. Materials and methods: The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation induced thermoluminescent signals in glass screens taken from mobile phones. Results: In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques. Conclusions: Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios

RENEB Inter-Laboratory Comparison 2017: limits and pitfalls of ILCs.

International audienceIn case of a mass-casualty radiological event, there would be a need for networking to overcome surge limitations and to obtain rapid homogeneous results among biodosimetry laboratories. To achieve this, reported aberration frequencies or estimated doses should be consistent within the network. Inter-laboratory comparisons (ILCs) are widely accepted to reach such homogeneity. At the European level, there has been a great effort to harmonize biological dosimetry laboratories, particularly during the MULTIBIODOSE and RENEB projects. To further the efforts of harmonization, the RENEB consortium launched this intercomparison where all steps in the process were evaluated, from blood shipment to dose estimation. The present exercise involving 38 laboratories from 21 countries also aimed to evaluate the statistical tools used to compare laboratory performance.Blood samples were irradiated at three different doses, 1.8, 0.4 and 0 Gy (samples A, C and B) with 4-MV X-rays at 0.5 Gy min-1, and sent to the participant laboratories, each requested to analyze 500 cells per sample and to report the observed frequency of dicentrics and the estimated dose.This ILC demonstrates that blood samples can be distributed among laboratories worldwide in order to perform biological dosimetry in the event of a major accident. Having achieved the first stage of harmonization, issues were identified with the statistical tools available for ILC analysis that were not able to take advantage of the richness of the results from large ILCs. Even though Z- and U-tests are accepted methods for biodosimetry ILCs, fixing the number of analyzed metaphases to 500 for all investigated doses leads to significant differences of their score distributions in terms of normal approximation. This makes the establishment of a common threshold inappropriate for evaluating a laboratory performance across different dose levels.Another issue highlighted by this ILC is the question of the diversity of dose-effect curves. It clearly appears that, despite the initial advantage of including the scoring specificities of each laboratory, the lack of defined criteria to evaluate the robustness of each laboratory’s curve seems to be a disadvantage for the model of "a curve per laboratory".Finally, and with the same spirit of unification, it seems relevant to develop tools that are better adapted to the collection and processing of results produced by the various participant laboratories. Confidently, after an initial harmonization phase, a new step towards the optimization of laboratory networks in biological dosimetry and associated ILC is now beginning

Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans – joint RENEB and EURADOS inter-laboratory comparisons

PURPOSE:RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation.MATERIALS AND METHODS:The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation-induced thermoluminescent signals in glass screens taken from mobile phones.RESULTS:In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques.CONCLUSIONS:Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios