Determination of the source of radioactive particles in a marine environment using SIMS and ICP-MS

The characterization, by secondary ion mass spectrometry (SIMS) and inductively coupled plasma mass spectrometry, of uranium and plutonium isotopic compositions in highly enriched particles found on the Scottish coast, allowed the determination of their origin. The particles were identified as an aluminium uranium matrix fuel irradiated in an MTR reactor to a burnup of 25 to 30%. The SIMS analysis also established the Al/U ratio in the alloy and characterized the impurities, showing that the other major elements present in the particles are not directly located with the uranium spots.