Estimation of birth year by radiocarbon dating of tooth enamel: Approach to obtaining enamel powder

J Forensic Leg Med. 2019 Feb;62:97-102. doi: 10.1016/j.jflm.2019.01.013. Epub 2019 Jan 29.


Atmospheric radiocarbon (14C) levels increased from 1955 to 1963 due to atmospheric nuclear weapon tests, and then decreased. As 14C accumulates in human tooth enamel while the enamel is being formed, 14C can be used to estimate the birth year of unidentified bodies. Measurement results of 14C content in tooth enamel using accelerator mass spectrometry vary depending on the enamel's sample site. To address this problem, a method for equalizing samples using a pulverizer was considered in this study. Regarding the tube and cone used as the pulverizer, (1) a polycarbonate tube and stainless steel cone, (2) a stainless steel tube and cone, and (3) a tungsten carbide tube and cone, were compared. In (1), the modern carbon ratio was approximately half that of the normal ratio of 100 pMC, with which accurate dating was impossible, and in (2), a high background value was obtained for IAEA-C1, which was pulverized using a reusable tube and cone. In (3), the 14C content for IAEA-C1 pulverized using reusable tube and cone, which was washed with quartz sand, was 0.31 ± 0.01 pMC. This result did not show any problems regarding background value. Therefore, the use of tungsten carbide products and washing with quartz sand is recommended for 14C measurement of pulverized teeth.

Keywords: Age estimation; Birth year; Bomb-curve; Pulverization; Radiocarbon; Tooth enamel; Tungsten carbide; Unidentified body.

MeSH terms

  • Age Determination by Teeth / methods*
  • Carbon Radioisotopes / analysis
  • Dental Enamel / chemistry*
  • Forensic Dentistry / methods
  • Humans
  • Mass Spectrometry
  • Powders
  • Quartz
  • Radiometric Dating*
  • Specimen Handling
  • Tungsten Compounds


  • Carbon Radioisotopes
  • Powders
  • Tungsten Compounds
  • tungsten carbide
  • Quartz