Lag time of modern bomb-pulse radiocarbon in human bone tissues: New data from Brazil

• Published in: Forensic science international Vol. 331; p. 111143
• Main Authors: Ubelaker, Douglas H., Plens, Cláudia R., Soriano, Evelyne Pessoa, Diniz, Marcus Vitor, de Almeida Junior, Erasmo, Junior, Eduardo Daruge, Júnior, Luiz Francesquini, Machado, Carlos Eduardo Palhares
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.02.2022; Elsevier Limited
• Subjects: Adult; Age; Bomb-pulse; Bombs; Bone; Bone and Bones; Bones; Brazil; Carbon; Collagen; Death; Dental enamel; Diaphysis; Estimation; Ethics; Female; Femur; Forensic osteology; Forensic sciences; Human remains; Humans; Lag time; Male; Middle Aged; Mortality; Occipital bone; Parietal bone; Radiocarbon; Spine; Testing laboratories; Time since death; Tissues; Vertebrae; Brazil; Time since death; Radiocarbon; Bone; Bomb-pulse
• ISSN: 0379-0738; 1872-6283
• DOI: 10.1016/j.forsciint.2021.111143

Radiocarbon analysis with reference to the modern bomb-curve was conducted using 68 bone samples of a vertebral body, femoral diaphysis, occipital bone, and parietal bone of 17 adults from Brazil. All individuals were born in 1963, thus analysis focused on the correlation with atmospheric values during the more recent, falling portion of the curve. Ages at death ranged from 43 to 54 years with representation of both sexes. Lag time (difference between the actual death date and the year of correspondence of the radiocarbon value with the curve) was evaluated for each individual and each tissue. The mean of the lag time values was 20.2 years, and the median was 22.0 years. The femur had the highest lag time median (29.5 years) among the bone groups, followed by the occipital (25.5 years), parietal (23.5 years) and the vertebra (8.0 years). The same pattern was observed for both sexes, but females tended to have lower lag time values than males. Different tissues presented considerable variation in lag time with vertebral bodies the least and the femoral diaphysis the greatest. These data suggest that individual age at death and the associated lag time must be considered in estimating the approximate death date. The lag time values for vertebral bodies were lower and with less variability in comparison with values for the occipital, parietal, and femur indicating greater consistency of that bone group for time since death estimation in the studied sample. •Radiocarbon analysis with reference to the modern bomb-curve was conducted with samples from Brazil of known dates of birth and death.•The research reports post 1963 lag time for the occipital, vertebral body, parietal and midshaft femur.•Vertebral bodies produced the lowest lag time with less variation compared to values from the other samples.