O42. Realizing the European Network of Biological Dosimetry ‘RENEB’: Results of 2 intercomparison exercises for the micronucleus assay

Introduction In the framework of the RENEB project, two intercomparison exercises were conducted to assess the suitability of the cytokinesis-block micronucleus assay, and to evaluate the capacity of a large laboratory network performing biodosimetry for radiation emergency triages. Twelve European institutions participated in the first exercise, and four non-RENEB labs were added in the second one. Materials and methods Irradiated blood samples were shipped to participating labs, whose task was to culture these samples and provide a blind dose estimate. Micronucleus analysis was performed by automated, semi-automated and manual scoring procedures. Results The dose estimates provided by the network laboratories were in good agreement with the true administered doses. The most accurate estimates were reported for the low dose points ( 1 Gy). For higher dose points ( > 2.5 Gy) a larger variation in estimates was observed, though in the second exercise the number of acceptable estimates increased satisfactorily. Higher accuracy was achieved with the semi-automated method. Conclusion The results of the two intercomparsion exercises performed by our network demonstrate that the micronucleus assay is a useful tool for large-scale radiation emergencies, and can be successfully implemented within a large network of laboratories. The results further emphasize the importance of performing regular intercomparison training exercises within a specialised biodosimetry network.