In order to have comparable data in time and space, the aim of the work package 3 of the MetroPOEM project is to produce two candidate reference materials, comprising common radioactive pollutants found in environmental samples (²⁴¹Am, ²³⁷Np, ²³⁹Pu, ²⁴⁰Pu, ²³⁴U, ²³⁵U, ²³⁶U and ²³⁸U). Two matrices were chosen, one liquid and one solid. These materials will be used in an interlaboratory comparison, where partners will use radiometric and/or mass spectrometry measurements to determine the concentrations and isotopic ratios of
the radionuclides.
The synthesis of the candidate reference materials will be described in a publication in 2025. Indeed, this work was selected for an oral communication at the ICRM 2025 conference in May 2025 and the authors plan to submit a paper associated with the talk. The paper must be submitted by 18^th April 2025.
The first part of gives the general strategy for the development of the two reference materials (RM): the method of spiking, the number of samples chosen for homogeneity and stability studies, the total amount of materials to produce and the sampling plan. The next two parts describe in more details the preparation and characterisation of the two reference materials.