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From: larry@kitty.UUCP (Larry Lippman)
Newsgroups: sci.med,sci.bio
Subject: Re: Dating age of humans
Message-ID: <2001@kitty.UUCP>
Date: Sat, 12-Sep-87 12:28:17 EDT
Article-I.D.: kitty.2001
Posted: Sat Sep 12 12:28:17 1987
Date-Received: Sun, 13-Sep-87 09:46:59 EDT
References: <26333@sun.uucp> <1960@kitty.UUCP> <3836@cit-vax.Caltech.Edu> <694@sugar.UUCP>
Organization: Recognition Research Corp., Clarence, NY
Lines: 23
Keywords: Ageing Human Carbon
Summary: Difficulty in resolution...
Xref: mnetor sci.med:3175 sci.bio:644

In article <694@sugar.UUCP>, peter@sugar.UUCP (Peter da Silva) writes:
> Couln't you do some sort of radioisotope testing on tooth enamel, and at least
> get the age since dentition?

	There are two problems that I see with this idea:

1.	Carbon-14 has a half-life of approximately 5,730 years.  Since the
	age of a living person is one percent or less of this value, one
	would be extremely hard pressed to obtain the required resolution
	using a scintillation counter.  Also, there is uncertainty in the
	C14 half-life, and it is typically expressed as 5,730 +/- 40 years.
	There is just no practicable way to measure such a slight amount of
	C14 decay.

2.	While I don't claim to have an in-depth understanding of tooth
	physiology, it would seem to me that there would be some migration
	of comtemporary C14 into the enamel, thereby nullifying any attempt
	to perform age calculations even IF the C14 decay could be measured.

<>  Larry Lippman @ Recognition Research Corp., Clarence, New York
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