After the Crisis: What Next?
Preparing for Long-Term Follow-up of an Exposed Population

Steven L. Simon PhD & Kiyohiko Mabuchi MD DrPH
Division of Cancer Epidemiology and Genetics
National Cancer Institute (NCI)
National Institutes of Health (NIH)
Bethesda Maryland USA

Abstract

After the emergency phase of a nuclear or radiological crisis abates, two questions will become of great importance with the first often asked even before the emergency is fully resolved: What are the expected radiation-related health consequences that will result from the event? Well after the exposure event, it will be equally important to answer: What were the actual radiation-related consequences of the event? Several strategies based on well understood dosimetric, epidemiologic, and risk assessment methods have the potential to answer these two questions and all rely on early capture of data about the exposed population, reliable dose estimation, and proper study design. The first question, that is, the number of expected long-term health consequences, principally cancer risks, can be estimated by risk projection methods. The reliability of such risk projections will be a function of the reliability of the input data on the number of persons exposed, their age and gender distribution, baseline disease rates, and approximate radiation doses. The second question, the excess in the expected number of cancers, can only be determined after disease has manifested itself through a properly designed health-risk follow-up study based on reliable estimates of organ doses. The need to collect data necessary for reliable, detailed, and unbiased individual dose assessments should not be overlooked early after radiation exposure events and has a value far beyond the initial steps of conducting medical triage. The presentation reviews these concepts and discusses specific types of data necessary to conduct a reliable long-term health risk assessment.