An international perspective on radiological threats and the need for retrospective biological dosimetry of acute radiation overexposures

The widespread use of ionizing radiation sources (machine-generated or from the decay of radioactive materials) across many disciplines including medicine, industry, and academia, has led to hundreds of instances in which one or more persons received an acute radiation overexposure. Successful medical diagnosis and management of these victims rested in part on a rapid, accurate determination of absorbed dose, which in many cases must be retrospective, due to the paucity of useful dosimetry data. This has led to the development of a number of biological dosimetry techniques to determine absorb dose retrospectively. The frequency of these accidental overexposures, however, has failed to serve as the impetus for the development of a cadre of experts in this field and an expansion in the number and availability of centers to perform the more sophisticated analysis necessary to accurately determine absorbed dose. Meanwhile, the world has seen an increase in the number of lethal terrorist events with time and there is realistic concern that the perpetrators of these events strongly desire to employ the specter of acute radiation overexposure in the future to induce mass panic in their target population. To that end, if any of these organizations achieves success, the existing capacity for rapid, accurate retrospective determination of absorbed dose may be overwhelmed, resulting in sub-optimal outcomes for the victims of such an event and potential mismanagement of medical resources designated for their care. This paper reviews existing techniques for retrospective biological dosimetry and diagnosis in relation to past experiences with overexposures, explores potential malevolent overexposure scenarios, and examines the need for public authorities to enhance national capabilities in light of the growing risk of an incident that will result in multiple acute radiation overexposures.