Many funeral directors encourage a viewing of a dead body at a commercial funeral home as part of a "package" that the family of the deceased pay for, without knowing that it is optional.[1] The primary purpose of embalming is to delay decomposition long enough to allow the body to be viewed.
In many countries, the law requires that dead bodies be chilled with dry ice or mechanical refrigeration to prevent microbial growth, though there are no laws mandating embalming, contrary to popular belief. Many cultures around the world use no artificial cooling at all, and bodies are regularly held for several days before their final disposal.
Special circumstances, such as an extended time between death and burial, or the transportation of remains on commercial flights (which often require unembalmed bodies to travel in expensive specialized containers), may necessitate embalming.
The most common embalming fluid is composed of organic chemicals and contains 5–29% formaldehyde, ethanol and water. This solution is biodegradable in time, but it cross-links proteins found in tissue-cell membranes, slowing down bacterial decomposition and inhibiting the body's breakdown in the earth. The ability of embalming fluid to contaminate soil or water tables has not been studied thoroughly. In alkaline soils, formaldehyde would be broken down through the Cannizzaro reaction and become Urotropin, but not all soils are alkaline.
Formaldehyde is highly toxic to all animals, and is "known to be a human carcinogen".[2][3][4][5] It is implicated in cancer, Amyotrophic lateral sclerosis, disorders of the nervous system, and other ailments. The U.S. Occupational Safety and Health Administration has the power to require embalmers to wear respirators.