The History of Body Preservation
From the ancient Egyptians to formaldehyde
- Ancient Egyptian method of embalming bodies:
- Brain tissue removed through the nostrils
- Internal organs removed through in incision and then kept in vases/jars
- Incision covered with beeswax to make the scar less obvious
- Body covered in natron to dehydrate the body, then covered in layers of linen cloths.
- The ancient Persians immersed their dead bodies in jars of honey and wax. This eliminated the problem of the air and microbes damaging the body.
- In the 15th century, embalming fluids usually contained mixtures of wine, camphor, turpentine, lavender oil, ronin , and mercury sulfide.
- 17th century physician Gabriel Clauderus introduced "balsamic spirit."
- Formaldehyde finally began to be used in the early 1900s and was the favorite among embalming fluids.
- Ferdinand Blum discovered formaldehyde's useful properties by accident. The 4% aqueous solution he was using make his fingers stiff.
- Reactions of formaldehyde
- Forms methylene glycol: preserves tissue
- Formaldehyde reacts with oxygen to yield formic acid, which causes pigments to form on the body.
- The pH of blood becomes very acidic right after death because of the production of lactic and carbonic acids. The 48 hours when this is occurring is when embalming usually takes place.
- A slightly alkaline embalming fluid can neutralize the acidic blood and help cell fixation.
- Tissue is preserved when formaldehyde forms cross-links with protein end groups and a stable, complex matrix is produced.
- Rate of cell preservation depended on concentration, pH, and temperature.
- The reaction with protein end groups begins at a much lower pH when using glutaraldehyde than formaldehyde.
- Protein binding is much stronger with glutaraldehyde, with a more comples and cross-linked product.
- The protein-aldehyde that is made with glutaraldehyde is much more stable than that made with formaldehyde.
- Penetrates into skin more evenly than formaldehyde.
- Formaldehyde remains premier embalming fluid in the U.S. because its price is more reasonable and it is less toxic and irritating to humans.
McKone, Harold T. "From natron to formaldehyde, preserving bodies has been a chemical undertaking." American Chemical Society 2002.