Not all organs die at the same time when a person dies. Here are the stages of decomposition of the body explained by Dr Michel Sapanet, forensic doctor at Poitiers University Hospital.
When the body is alive, millions of biochemical reactions take place constantly within cells to ensure functioning of each organ. But “uOnce blood circulation is interrupted, when natural death by cardiac arrest, the organs are no longer irrigated and the activity of their cells will gradually stop. Cardiac arrest causes other organs to fail one after the other. Death is not an instantaneous phenomenon: not all organs die at the same time. This is also what makes it possible to transplant organs even though the donor has died. This cessation of metabolism, that is to say of all the functions of the body (heartbeat, blood circulation, breathing, interneuronal communication, etc.) will have consequences on the state of the body which will gradually deteriorate, immediately asks Dr Michel Sapanet, director of the Poitou-Charentes Institute of Legal Medicine. However, what happens after death depends greatly on the causes of death and conditions of conservation of the body“. The process during which the body breaks down can be long.
1. The body cools down
In life, the normal temperature of the human body is around 37°, more precisely between 36 and 37.8°C depending on the activity. After death, body temperature will gradually come into balance with the environment in which the body is located. “This cooling will take time: at first, we will not notice a difference in temperature, but after one to two hours, the body will lose on average 1°C per hour“, details the forensic doctor.
2. Red spots appear
When metabolism stops, blood vessels gradually become permeable : “The blood, which is no longer in circulation, will accumulate under the effect of gravity in the lower parts of the body, the red blood cells will accumulate and the hemoglobin will diffuse out of the vessels.“, explains Dr. Sapanet. This phenomenon is at the origin of the formation of large wine-colored spots called “cadaverous lividities”. These colors are generally visible one to two hours after death and increase in intensity for a few hours. “On a body lying on its back, these colors form on the back except in the support areas of the body such as the shoulder blades or buttocks for example.“, he explains.
3. The body stiffens
Since the metabolisms no longer function, the body will become acidic and under the effect of acidity, the muscle fibers will contract completely involuntarily. “The body is then very rigid: all the muscles stiffen, first those of the neck, then those of the muscles of mastication. Furthermore, this rigor mortis manifests itself by very tense and curled fingers and very rigid joints.“, describes the specialist.
4. A green spot forms on the abdomen
24 to 48 hours after death, a green spot will form on the wall of the abdomen, approximately where the appendix is located. This green stain is one of the first visible signs of rot. “It corresponds to the migration of pigments from fecal matter which pass through the walls and which appear on the surface“, explains Dr. Sapanet.
5. The abdomen swells
All the bacteria naturally present in the body will produce gases which will cause the abdomen to swell. “This phenomenon will cause the blood that was stagnating in the vessels to move: this is what we call posthumous circulation. The superficial veins of the body will then form a very dark network“, indicates the expert.
6. The body has a very unpleasant odor
We enter the rot cycle : bacteria living in the body begin by attacking the digestive system, then all the organs (liver, spleen, heart, brain, etc.). Chemical reactions linked to the decomposition of the body will then occur. “The body begins to ooze black and red fluids, the skin gradually turns greenish then black and the body gives off very unpleasant odors. In a person with a significant excess fat, the fat will liquefy and large bubbles will appear on the surface of the skin with putrefactive liquids or liquefied fat inside.“, describes the forensic doctor.
• What does a dead body smell like? “The first hours following death, the body has a smell of cold meat. This smell will evolve and tend towards an odor characteristic of certain strong cheeses such as Époisses or Maroilles“, compares our interlocutor. During decomposition, the body’s proteins undergo the same type of transformation as the proteins in certain cheeses. Furthermore, when they degrade, fats emit a smell of rancid butter. Bones, even when cleaned, also retain that rancid butter smell.
7. Flies lay eggs on the body
If the body is not in a perfectly enclosed place (morgue, coffin), flies will come and lay eggs on the body as soon as its temperature drops. “These flies will generally lay eggs near openings and in the most humid places. Maggots will gradually develop, penetrate the skin and then feed on the body“, indicates the forensic doctor.
8. The flesh decomposes and the body dries up
The rot continues… All the flesh will decompose, liquefy or be eaten by maggots. The putrefied remains come out through the nose, mouth or anus. The body becomes dehydrated and dries out.
• How long does it take for the body to decompose? The body will deteriorate more or less quickly depending on the ambient temperature, but also on the size of the person. If it is cold, the body will take much longer to decompose. On the other hand, complete decomposition in midsummer can occur within a month. “When the body is in a coffin, basically the same steps take place, but the decomposition process takes much longer, sometimes several years.“, he emphasizes.
9. Hair falls out
“We will immediately destroy a myth: no, hair does not grow after death. When on a corpse, we have the appearance of a beard growing, it is simply the skin which is dehydrated, which retracts and which brings out the length of the hairs“, explains our interlocutor. Hair falls out when the scalp rots. Hair also falls out at the same time as the skin decomposes. On the other hand, nails decompose much more slowly because they are horn and are better preserved.
10. The skeleton falls apart
At the end of the decomposition process, only the skeleton and ligaments will remain. The ligaments dry out and shrink and the skeleton dislocates: the fingers and toes disunite first, followed by the large joints.
Thanks to Dr Michel Sapanet, forensic doctor at Poitiers University Hospital, director of the Poitou-Charente Institute of Legal Medicine. and author of the book “Live from the morgue” by Editions Plon (to be published on January 23, 2020)
