Measuring atomic bomb-derived 14C levels in human remains to determine the Year of Birth and/or Year of Death

The goal of this award is to further investigate C14 measurement as a potential tool for forensic analysis by measuring C14 levels in different tissue compartments from the remains of 20 individuals with known birth and death dates. The measurements will be used to model C14-turnover rates and examine the model's predictions of year of both year of birth and year of death. The resolution of the method will vary depending upon several factors, however preliminary investigations suggest it is of the order of one year. Between 1955 and 1963 above-ground nuclear testing generated high concentrations of radioactive carbon (C14) in the earth's atmosphere. Since 1964-65, atmospheric levels of bomb-derived C14 have been falling as the radioactivity passes from the atmosphere into the oceans and the biosphere. The rapid year-to-year changes in atmospheric levels means that the amount of bomb-C14 within an individual depends primarily upon birth year, diet, and the tissue being measured. Theory and preliminary experiments suggest that the level of bomb-C14 within different tissue compartments of human remains can be used to derive data potentially of forensic interest, namely the year of birth and death. ca/ncf