Radiocarbon dating results on bones need not be subjected to an age offset but bone samples have time-width.Literature suggests that a bone does not cease to assimilate carbon from the biosphere until death; there is a turnover time of about 30 years for human bone and a shorter period for animal bone.For most organisms that have bones, the time of their death is contemporaneous with their cessation of exchange with the biosphere.
Depending on the age of the organism that produced the organic acids, the AMS lab’s result might reflect a radiocarbon age younger or older than the bone sample’s true age.
Bones can also be exposed to modern sources of carbon due to plant rootlet intrusions.
The protein, which is mostly collagen, provides strength and flexibility to the bone whereas the hydroxyapatite gives the bone its rigidity and solid structure.
In theory, both organic and inorganic components can be dated.
Considering that bones are often found surrounded by different kinds of organic matter, bones are arguably one of the most highly contaminated samples submitted to AMS labs for radiocarbon dating.
The common contaminants are humic and fulvic acids, which are organic acids present in soil that are produced by the microbial degradation of plant or animal tissues.
According to literature, other organic compounds that can contaminate bone samples are polyphenols, polysaccharides, lignins, and degraded collagen.
Depending on the location of the excavation, bones can also be contaminated by limestone.
The effect of contamination on bone samples that were subjected to AMS dating is dependent on these factors: type of contaminant, degree of contamination, and the relative age of the bones and the contaminant.
If limestone has not been removed prior to AMS carbon dating, the radiocarbon age will be much older than the sample’s true age.
Modern sources of carbon can make the AMS carbon dating result of a bone younger than its true age.