A Bioplastic Coating Did Not Causes Carbon 14 Errors
While a microbiotic growth found on some archeological artifacts may be present on the Shroud, it is questionable if there can be sufficient quantity of this newer material to alter the measurements enough to make a first century cloth seem medieval.
A bioplastic (biopolymer) are produced from living and growing organisms. As such, they contain proteins, amino acids, and nucleic acids. Any compound containing these elements can be detected by several methods including protein spot tests. There is no measurable protein except in the bloodstains.
Ray Rogers (see curriculum vitae summary below) responds to the question: "Can the presence of a "bioplastic polymer" coating anywhere on the Turin Shroud be confirmed? Could it affect the radiocarbon age determination?"
No. Stephen Mattingly of the University of Texas has proposed a hypothesis that a "bioplastic" coating on the Shroud produced an error in the 14C analysis that was used in obtaining the 1988 age estimate for the Shroud of Turin. He also proposed that common skin bacteria produced the image. I believe that there are several things wrong with these hypotheses.
Even assuming that the coating formed all at once in the 20th Century during a highfallout time, when bomb-produced 14C was high, an observable error in the age determination would require the addition of a significant amount of material to the surface of the Shroud. Mattingly proposes that the added material is a product of microbiological action. Such microbiological processes require fixed carbon, nitrogen, phosphate, sulfur, etc., to produce the products observed as biopolymers. The chemical components of biopolymers can be detected with great sensitivity.
Joan L. Rogers took authentic Shroud fibers, which she laboriously extracted from the STURP sampling tapes by washing them free of adhesive with xylene (not a solvent for any "bioplastic polymers"), to Metuchen, NJ, for laser-microprobe Raman analysis. The analysis is extremely sensitive, but nothing was observed that would indicate a "bioplastic polymer."
She also took fibers to the NSF Mass Spectrometry Center of Excellence at the University of Nebraska. They did pyrolysis-mass-spectrometry on the fibers. Their system was sufficiently sensitive to detect traces of the oligimers (low-molecular-weight polymers) from the polyethylene bag that Professor Luigi Gonella of Turin had used to wrap the Raes samples; however, the polyethylene never touched the samples. They were protected inside acid-free conservator's paper.
The NSF facility observed the pyrolysis products of polysaccharides as a function of their relative temperatures of decomposition. For example, they detected traces of furfural from the anomalous pentosan gum layer in the radiocarbon-sample area. They easily detected hydroxyproline from the proteins of the blood spots. No evidence for a bioplastic polymer was detected on either non-image or image areas.
R. Rogers, J. Rogers, and A. Adler spent many hours looking at samples from the Shroud under microscopes and running microchemical spot tests. There were no anomalous indexes of refraction, there were no amorphous materials cementing fibers (except for the blood/serum and some pentosans on yarn segments taken from the Raes and radiocarbon samples), and there were no sulfur compounds on the surface (except in the blood/serum areas). No "bioplastic polymers" are absolutely devoid of amino acids (proteins) and sulfoproteins. There is no significant amount of bioplastic polymers on the main part of the Shroud.
In order to change the carbon date, the organisms Mattingly postulates must be utilizing carbon dioxide from the atmosphere. A 14N n-p 14C nuclear reaction in the upper atmosphere is the source for 14C-containing carbon. The addition of modern carbon is the only way to decrease the apparent age of ancient carbon-containing material. The organisms that fix CO2 are photosynthetic, and they are "obligate aerobes." They must have oxygen in their atmosphere as well as CO2. They need a source of energy. They get that energy by absorbing light into complex colored molecules that then provide electrons for the chemical reactions that involve the carbon and other reactants. The final products of photosynthesis are sugars, polysaccharides, nucleic acids, proteins, etc. Nature builds flax (linen), trees, grass, and little colored microorganisms by photosynthesis. All of the 14C in our bodies comes originally from photosynthetic organisms. The most important organisms that fix CO2 are plants, mostly green plants.
Mattingly's postulation of an appreciable amount of slime/biopolymer requires photosynthetic aerobes. They all use water, CO2, and light, and they produce fixed carbon and oxygen. The oxygen we breathe comes from photosynthesis. Appreciable photosynthesis would not be expected on the Shroud, because historically it was stored dry in a dark place.
All photosynthetic organisms contain intensely colored pigments, for example chlorophyll. All such pigments absorb visible light and reflect intense colors. They all show distinctive spectra. Some of the most important observations made by STURP in 1978 were the reflectance spectra of the image, blood, and non-image areas of the Shroud. We could not have missed any pigments that are involved in photosynthesis.
If the organisms involved in biopolymer production (like fungi) used only the carbohydrates in the Shroud for their metabolic purposes (we call it "rotting") and did not fix atmospheric carbon by using pigments, the biopolymer product would show the same carbon age as the Shroud. Such effects have been observed. The organisms would use fixed carbon (e.g., the sugar units of cellulose) and yield carbon dioxide and cell components. Only part of the metabolized carbon would end up in a slime/polymer layer, and the cloth would tend to disappear much faster than the polymer appeared.
All biopolymers are products of living organisms. They contain proteins, amino acids, and nucleic acids. Algal cells contain 3.9% nitrogen and 3.3% phosphorus. Fungal cells contain about 0.9% phosphorus and 2.9% nitrogen. Compounds containing these elements can be detected by several of the analytical methods STURP used. The polymers can be nearly pure polysaccharides, but they all give protein spot tests.
STURP used all of the protein spot tests, e.g., Hycel biuret followed by Fisher Folin reagent, biuret Lowrey, amido black, iodine-azide to look for sulfoproteins, and a sensitive pyrolysis test that detects the purine from proteins. There was no protein in areas other than the blood flows. There was no bioplastic-polymer coating.
Mattingly and Garza-Valdes presented a photomicrograph of a linen fiber from the radiocarbon sample. It shows a thick coating and what are indicated to be "filamentous bacteria, a snake-like growth." They did no analyses to support their claims, and they apparently know nothing about the structure of linen. Features identical to the "filamentous bacteria" are common in linen samples. They are what are called "ultimate cells."
Linen fibers are made of parallel bundles of these cells, cemented together with lignin and hemicelluloses. Details can be found in a paper presented by Jeanette Cardamone ["The Turin Shroud Past, Present and Future," International Shroud Scientific Symposium (Torino 2-5 March 2000)]. There are images of flax fibers, drawings, and text explanations. She has said that: "Any fuzziness could be due to abrasion that causes micro-fibers to develop on the surface of the fiber and, critically, remain attached to it." In other words, things that look like filamentous bacteria are to be expected on linen fibers.
Ultimate cells are easy to differentiate from bacteria, because the ultimate cells are crystalline and birefringent. It is too bad that the "bioplastic-polymer" proponents did not do any analyses of their samples. They have caused massive confusion and mischief.
Much of the scientific material on this site is based on the work of Ray Rogers. Rogers, a chemist, is a science Fellow of the University of California, Los Alamos National Laboratory and a charter member of the Coalition for Excellence in Science Education. He has published many scientific papers in peer-reviewed journals and U.S. Government publications. In 1978, together with several other scientists, he was invited to personally examine the Shroud of Turin in Italy for several days. He collected numerous measurements and samples of fibers and particulate materials for further study. Rogers died March 8, 2005..
More information is available from links at Shroud of Turin Story and at A Forensic Science CSI - Pictures of Jesus on the Shroud of Turin