Did a biological polymer throw off the carbon dating?
Few think so. Unfortunately, this speculative explanation for why the carbon dating might have been wrong received a considerable amount of undue attention after Harry E. Gove of the University of Rochester, one of the significant players in the development of Mass Spectrometry Analysis for carbon dating, wrote, "There is a bioplastic coating on some threads, maybe most. . . . [if thick enough it] would make the fabric sample seem younger than it should be."
Thick enough? An error of 1300 years resulting from bacterial contamination would have required a layer approximately doubling weight of the tested samples. Moreover:
- Biological polymers do not obtain their carbon from the atmosphere but from their host. That would have been the fibers of the cloth. Thus the bioplastic would have had the same carbon 14 ratios as the Shroud and this would not affect the dating.
- Using highly sensitive pyrolysis-mass-spectrometry, scientists at the National Science Foundation Mass Spectrometry Center of Excellence at the University of Nebraska could not detect any such polymers on Shroud fibers.
Some have argued that the corner from which the sample was taken would have been handled more often than other parts of the Shroud, increasing the likelihood of contamination by bacteria and bacterial residue. Bacteria and associated residue (bacteria by-products and dead bacteria) carry additional carbon and would skew the radiocarbon date toward the present. So far, this is only an argument and there is no evidence to support this contention.
For the most part, serious Shroud researchers do not take this argument seriously.
- What led to the bioplastic coating hypothesis?
- What was the reaction to the 1988 carbon dating?
- Why did the bio plastic hypothesis ultimately fail to convince researchers?