How fast does a human body begin to decompose, and what are the products?

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The University of Tennessee maintains an experimental area where observations are made on decomposing corpses. They find that flies lay their eggs in wounds on dead bodies, and maggots appear before 30 hours at about 23ºC. This approximates the time required for liquid decomposition products to begin to appear on the surface of a body. We could not find any evidence for the migration of liquid decomposition products through the cloth; therefore, the cloth could not have been in contact with the body for very long.

Decomposing bodies start producing ammonia (NH3) in the lungs quite soon after death, and the ammonia diffuses outward through the nose and mouth. Ammonia is lighter than air, and it diffuses rapidly. The rate of production of ammonia decreases with time after death.

Within a few hours, depending on weather conditions, a body starts to produce heavier amines in its tissues, e.g., putrescine (1,4-diaminobutane), and cadaverine (1,5-diaminopentane). These amines are much heavier than air, and they diffuse relatively slowly. Experiments prove that slow diffusion relates to increased resolution in image formation. The early appearance and rapid diffusion of low-molecular-weight ammonia from the nose and mouth might help explain the greater amount of image color between the nose and mouth, in the beard, and into the nearby hair. It will also diffuse through the cloth more quickly and reach the back side of the cloth in greater concentration. Ammonia will diffuse about 20 cm through air while cadaverine is diffusing only 6 cm.

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 Shroud of Turin Pictures of Jesus
 The Shroud of Turin Story

© 2004 Daniel R. Porter, Bronxville, New York

Carbon 14 Challenge

Shroud Description

  • The cloth

    The Shroud is a single piece of linen cloth measuring about 14 feet by 3½ feet. The weave is a 3 over 1 herringbone weave. It is bloodstained and shows faint ventral and dorsal images of a man who, by the wounds that are visible, appears to have been crucified. He seems to be in burial repose.

    The bloodstains

    The bloodstains on the Shroud are composed of hemoglobin and give a positive test for serum albumin. Numerous tests confirm this.

    The images

    The Shroud's images are superficial and fully contained within a thin layer of starch fractions and saccharides that coats the outermost fibers of the Shroud. The coloration is a caramel-like product or the product of an amino/carbonyl reaction. Where there is no image, the carbohydrate coating is clear. There is also a very faint image of the face on the reverse side of the Shroud which lines up with the image on the front of the cloth. There is no image content between the two superficial image layers indicating that nothing soaked through to form the image on the other side.

    Until recently, it was widely believed that the images on the Shroud of Turin were produced by something which resulted in oxidation, dehydration and conjugation of the polysaccharide structure of the fibers of the linen itself. This has been shown to be incorrect. The coating, whether imaged or clear, can be reduced with diimide or removed with adhesive leaving clear cellulose fiber.

    The images as they appear on the Shroud are said to be negative because when photographed the resulting negative is a positive image.

    The Turin Shroud was examined with visible and ultraviolet spectrometry, infrared spectrometry, x-ray fluorescence spectrometry, thermography, pyrolysis-mass-spectrometry, laser­microprobe Raman analyses, and microchemical testing. No evidence for pigments (paint, dye or stains) or artist's media was found anywhere on the Shroud.

 

LINKS

Papers by Raymond N. Rogers at shroud.com