Identification of a chemical fingerprint linking the undeclared 2017 release of ¹⁰⁶ Ru to advanced nuclear fuel reprocessing

Abstract

Significance In the fall of 2017, a massive, undeclared release of 106 Ru occurred that was detected across Eurasia. To conclusively address the nature of the release, we have used carefully selected and established chemical transformations to reveal a chemical fingerprint for the 106 Ru contaminant that is uniquely consistent with specific methodology employed in the reprocessing of spent nuclear fuel. In view of international attention and investigation to date, this chemical fingerprint is the first direct evidence to this effect. This work serves, by example, as a potentially valuable addition to the field of nuclear forensics, considering that it is the only means to extract historical information from a radiopure contaminant in the absence of stable elemental anomalies.