Over the past six decades, the amount of radiocarbon in people or their remains depends heavily on when they were born or, more precisely, when their tissues were formed.
Forensic anthropologists at The University of Arizona took advantage of this fact in a recent study funded by NIJ.
Barring any future nuclear detonations, this method should continue to be useful for year-of-birth determinations for people born during the next 10 or 20 years.
Now, new applications for the technique are emerging in forensics, thanks to research funded by NIJ and other organizations.
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.
To determine year of birth, the researchers focused on tooth enamel.
Adult teeth are formed at known intervals during childhood.
The researchers found that year-of-death determinations based on nails were accurate to within three years.
The generally poor post-mortem preservation of soft tissues would be a limiting factor to this approach.
However, the researchers suggested that soft tissue radiocarbon content would be transferred to, and preserved in, the pupal cases of insects whose larvae feed on these tissues.
Such insects are simply another link in the food chain.
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