Livermore researcher Bruce Buchholz and colleagues at the Karolinska Institute are looking at victim's teeth to determine how old they are at the time of death. Using the Lawrence Livermore's Center for Accelerator Mass Spectrometry, Buchholz determined that the radioactive carbon-14 produced by above-ground nuclear testing in the 1950s and 1960s remains in the dental enamel, the hardest substance in the body. The radiocarbon analysis showed that dating the teeth with the carbon-14 method would estimate the birth date within one year. Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster, because the age at death, birth date, and year of death, as well as gender, can guide investigators to the corr