User:Amstutz2/sandbox

Putrefaction is the 5th stage in the process of decomposition following Pallor Mortis, Algor Mortis, Rigor Mortis and Livor Mortis. This process references the break down of the body of a human or animal after death. In broad terms it can be viewed as the breakdown of proteins in the body and the eventual breakdown of the cohesiveness of tissues and the liquidation of organs. This is caused by the decomposition of organic matter by bacterial or fungal digestion, which creates the release of gases that infiltrate the body’s tissues and leads to the deterioration of the of tissues and organs.

The approximate time it takes putrefaction to occur is dependent on various factors. There are internal and external factors that affect the rate of putrefaction. Internal factors include the age at which death has occurred, the overall structure and condition of the body, the cause of death and external injuries arising before or after death. External factors include environmental temperature, moisture and air exposure, burial factors, and light exposure. The first signs of putrefaction are signified by a greenish discoloration on the outside of the skin on the abdominal wall corresponding to where the large intestine begins, as well as under the surface of the liver.

Certain substances such as, Carbolic Acid, Arsenic, Strychnine, and Zinc Chloride can even be used to delay the process of putrefaction in different ways based on their chemical make up. To understand the process of Decomposition as well us how these substances affect the rate of putrefaction there are facilities known as Body farms where cadavers are put in different environmental conditions to study how the process of decomposition can be affected. There are 6 University Body Farm Research Facilities in the world all located within the United States, which include the University of Tennessee at Knoxville, Western Carolina University, Texas State University, Sam Houston State University, Southern Illinois University, and Colorado Mesa University.Amstutz2 (talk) 04:24, 1 March 2016 (UTC)

Description
In thermodynamic terms, all organic tissue is a store of chemical energy, which, when not maintained by the constant biochemical maintenance of the living organism, begins to hydrolyse into amino acids, chemically simpler organic components. The breakdown of the proteins of a decomposing body is a spontaneous process, protein hydrolysis, which is accelerated as the anaerobic bacteria of the digestive tract consume, digest, and excrete the cellular proteins of the body.

Putrefaction in human hands after several days underwater in Florida, United States The bacterial digestion of the cell proteins weakens the tissues of the body. As the proteins are continuously broken down to smaller components, the bacteria excrete gases and organic compounds, such as the functional-group amines putrescine and cadaverine, which carry the noxious odor of rotten flesh. Initially, the gases of putrefaction are constrained within the body cavities, but eventually diffuse through the adjacent tissues, and then into the circulatory system. Once in the blood vessels, the putrid gases infiltrate and diffuse to other parts of the body and the limbs.

The visual result of gaseous tissue-infiltration is notable bloating of the torso and limbs. The increased, internal pressure of the continually rising volume of gas further stresses, weakens, and separates the tissues constraining the gas. In the course of putrefaction, the skin tissues of the body rupture and release the bacterial gas. As the anaerobic bacteria continue consuming, digesting, and excreting the tissue proteins, the body's decomposition progresses to the stage of skeletonisation. This continued consumption also results in the production of ethanol by the bacteria, which can make it difficult to determine the BAC in autopsies, particularly in bodies recovered from water.[2]

Generally, the term decomposition encompasses the biochemical processes that occur from the physical death of the person (or animal) until the skeletonisation of the body. Putrefaction is one of seven stages of decomposition; as such, the term putrescible identifies all organic matter (animal and human) that is biochemically subject to putrefaction. In the matter of death by poisoning, the putrefaction of the body is chemically delayed by poisons such as antimony, arsenic, carbolic acid (phenol), nux vomica (plant), strychnine (pesticide), and zinc chloride.

Approximate timeline
1-2 days: Pallor Mortis, Algor Mortis, Rigor Mortis, and Livor Mortis are the first steps in the process of decomposition before the process of putrefaction. 2–3 days: Discoloration appears on the skin of the abdomen. The abdomen begins to swell due to gas formation. 3–4 days: The discoloration spreads and discolored veins become visible. 5–6 days: The abdomen swells noticeably and the skin blisters. 2 weeks: The abdomen is bloated; internal gas pressure nears maximum capacity. 3 weeks: Tissues have softened. Organs and cavities are bursting. The nails fall off. 4 weeks: Soft tissues begin to liquefy and the face becomes unrecognizable. Leads to skeletonization where the skin, muscles, tendons and ligaments degrade exposing the skeleton.

General rule of thumb for the decomposition of organs in the body. 1)	Larynx and trachea 2)	Gastrointestinal organs (stomach, intestines and spleen) 3)	Liver and lungs 4)	Brain 5)	Heart 6)	Renal system (Kidneys, bladder and uterus) 7)	Skin, muscles, and tendons 8)	Bones

First external sign of putrefaction in a body lying in air is usually greenish discoloration of the skin over the region of caecum which appears in 12–24 hours. And the first internal sign is usually a greenish discoloration on undersurface of liver. The exact rate of putrefaction is dependent upon many external and internal factors such as weather, exposure, location, condition of body, cause of death and more. Thus, refrigeration at a morgue or funeral home can retard the process, allowing for burial in three days or so following death without embalming. The rate increases dramatically in tropical climates.

Factors affecting
Various factors affect the rate of putrefaction.

Exogenous (External)
Environmental Temperature: Decomposition is sped by high atmospheric or environmental temperature, with putrefaction speed optimized between 21 and 38 °C, further sped along by high levels of humidity. This optimal temperature assists in the chemical breakdown of the tissue and promoting microorganism growth. Decomposition nearly stops below 0 °C or above 48 °C.

Moisture and Air Exposure: Putrefaction is ordinarily slowed by the body being submerged in water, due to diminished exposure to air. Air exposure and moisture both can contribute to the introduction and growth of microorganisms, speeding degradation.

Clothing: Loose fitting clothing can speed up the rate of putrefaction, as it helps to retain body heat. Tight fitting clothing can delay the process by cutting off blood supply to tissues and eliminating nutrients for bacteria to feed on.

Manner of Burial: Speedy burial can slow putrefaction. Bodies within deep graves tend to decompose more slowly due to the diminished influences of changes in temperature. The composition of graves can also be a significant contributing factor, with dense, clay-like soil tending to speed putrefaction while dry and sandy soil slows it.

Light Exposure: Light can also contribute indirectly, as flies and insects prefer to lay eggs in areas of the body not exposed to light, such as the crevices formed by the eyelids and nostrils.[3]

Endogenous (Internal)
Age of Death: Stillborn fetuses and infants putrefy slowly due to their sterility. Generally, younger people putrefy more quickly than older people.

Sex: No effect.

Condition of the Body: A body with a greater fat percentage and less lean body mass will have a faster rate of putrefaction, as fat retains more heat and it carrie a larger amount of fluid in the tissues.

Cause of Death: The cause of death has a direct relationship to putrefaction speed, with bodies that died from acute violence or accident generally putrefying slower than those that died from infectious diseases. Certain poisons, such as potassium cyanide or strychnine may also delay putrefaction, while chronic alcoholism will speed it.

External Injuries:Antemortem or postmortem injuries can speed putrefaction as injured areas can be invaded by bacteria.

Delayed Putrefaction
Certain substances can delay the process of putrefaction. They include: Carbolic Acid: Arsenic and Antimony: Strychnine: Zinc Chloride:

Research
To understand the process of decomposition and how certain substances affect the rate of putrefaction there are facilities known as Body Farms, that subject cadavers to different environmental conditions to see how the rate of decomposition varies. There are 6 Body Farms in the world, all located within the United States. Each body farm is unique in it's environmental factors that can affect the rate of decomposition significantly such as humidity, sun exposure, rain or snow, altitude level and more.

University of Tennessee at Knoxville
The University of Tennessee's Forensic Anthropology Facility was established in 1981 as the first and largest body farm in the world to study human putrefaction.

Western Carolina University
Western Carolina University opened up a body farm known as the Forensic Osteology Research Station (FOREST) in 2006 being the second of its kind in the United States.

Texas State University
Texas State University opened its 26 acre Forensic Anthropology Research Facility (FARF) in 2008. It is used to train forensic anthropology students about the decomposition process as well as law enforcement for the purpose of searching for and the recovery of human remains.

Sam Houston State University
Sam Houston State University's body farm is known as the Southeast Texas Applied Forensic Science Facility (STAFS). It is home to 247 acres of land with cameras dispersed through out, keeping track of the decomposition process of donated cadavers.

Southern Illinois University
Southern Illinois University 's outdoor research Facility is known as The Complex for Forensic Anthropology Research. There primary mission is to understand the rate and pattern of decomposition in there unique environment. They are also known for there services including body recovery, skeletal and trauma analysis, as well as court testimonies.

Colorado Mesa University
The Forensic Investigation Research Station of Colorado Mesa University was opened in 2012 by placing its first animal species in it's outdoor facility. It has a unique environment compared to the other facilities as it is 4,750 ft above sea level and receives on average 8.6 inches of rain with 60% humidity.