Quality assessment in a Brazilian laboratory performing k0-NAA

This work is focused on the demonstration of the overall adequacy of the procedures introduced in a Brazilian laboratory for conducting the k0-standardized neutron activation analysis (NAA). Concentrations of 29 elements determined in certified reference materials of plants and geological matrices were evaluated. The study employed a comprehensive approach for method validation involving analyses of different certified reference materials under reproducible conditions. The results revealed that most of the experimentally determined values agreed well with the reference data, indicating that the adopted analytical system introduced no consistent bias. Despite the high uncertainties in the results for certain elements, the work underscores the effectiveness of the k0-standardized methodology in facilitating a multi-elemental capacity in NAA. The need to minimize changes for method validation, while addressing operational challenges faced due to the absence of a nuclear research reactor, was highlighted as a significant aspect of this research. Overall, the findings suggest that this method is a reliable approach for quality assessment in a laboratory context.