They measured carbon-14 levels in various tissues from 36 humans whose birth and death dates were known.
To determine year of birth, the researchers focused on tooth enamel.
Radiocarbon dating is a method of estimating the age of organic material.
It was developed right after World War II by Willard F.
They found that for teeth formed after 1965, enamel radiocarbon content predicted year of birth within 1.5 years.
Radiocarbon levels in teeth formed before then contained less radiocarbon than expected, so when applied to teeth formed during that period, the method was less precise.
In recent years, forensic scientists have started to apply carbon-14 dating to cases in which law enforcement agencies hope to find out the age of a skeleton or other unidentified human remains.
Half of the carbon-14 degrades every 5,730 years as indicated by its half-life.In order to date the artifact, the amount of Carbon-14 is compared to the amount of Carbon-12 (the stable form of carbon) to determine how much radiocarbon has decayed.The ratio of carbon-12 to carbon-14 is the same in all living things.Forensic anthropologists at The University of Arizona took advantage of this fact in a recent study funded by NIJ.
The researchers wanted to find out if they could identify a person's year of birth or year of death using precise measurements of carbon-14 levels in different post-mortem tissues.Adult teeth are formed at known intervals during childhood.