The latest comment from Greenboro Public Library posting on the Shroud of Turin way back in January of this year. Dana Riney wonders:
I’ve often wondered how the smoke of the fire which the shroud was exposed to would affect the radiocarbon dating of the material with which it was made. I haven’t read extensively on the subject, but believe that the dating is based on the rate of decay of carbon based material. Wouldn’t the smoke of a carbon based fire impregnating the material skew the results of such a test showing it to be much younger? That is a question for someone much smarter than me to answer. Reflecting on the chunk of wood found on Mount Ararat and claimed to be from Noah’s Ark (I believe it was found by a Frenchman named Navarre sp.), and found by radiocarbon dating to be much younger, how would the freezing cold affect the carbon dating of an object. I’ve seen deer steaks taken from my freezer and thawed after almost a year look as if they were taken from a deer tagged yesterday.
Dana, my understanding is that it would take an awful lot of smoke contamination, perhaps as much in weight as the original cloth to alter the date back to approximately the time of Christ. But then, that still wouldn’t do it because the cleaning procedures would have eliminated the vast majority of that carbon. As for the freezing cold suggestion, it should have no effect whatsoever. We are talking about radioactive decay which is not affected by temperature.
But there are significant, completely scientific, non-religious reasons to doubt the validity of the shroud’s dating. Chemical analysis, all properly peer-reviewed in scientific journals and subsequently confirmed by numerous chemists, shows that the sample that was tested was chemically unlike the whole cloth. It is now widely believed that the sample was a mixture of older, original threads and newer threads woven in as part of a medieval repair. Robust statistical studies as well as microscopic analysis support this theory. Given all this, we must therefore admit that we do not know how old the cloth is. If the newer thread is about half of the total amount of the sample – and it seems to be roughly so – it is possible that the cloth is from the time of Christ.