The Stages Of Human Decomposition | Aftermath Services
Death is a great unknown. It’s something that everybody will eventually experience, but while we can’t answer any existential questions about death, we can tell you what happens to your body after you die: decomposition.
Human decomposition is a natural process involving the breakdown of organic tissue after death. . While the rate of human decomposition varies due to several factors, including weather, temperature, moisture, pH and oxygen levels, cause of death and body position, all human bodies follow the same four stages of human decomposition.
What are the 4 Stages of Human Decomposition?
According to Dr. Arpad A. Vass, a Senior Staff Scientist at Oak Ridge National Laboratory and Adjunct Associate Professor at the University of Tennessee in Forensic Anthropology, human decomposition begins around four minutes after a person dies and follows four stages: autolysis, bloat, active decay, and skeletonization. Keep in mind, this process is what happens as long as the body remains undisturbed. Embalming and/or being sealed in a coffin can delay the decay process for years or even decades.
Stages of Decomposition: Body Decomposition Timeline
- 24-72 hours after death — the internal organs decompose.
- 3-5 days after death — the body starts to bloat and blood-containing foam leaks from the mouth and nose.
- 8-10 days after death — the body turns from green to red as the blood decomposes and the organs in the abdomen accumulate gas.
- Several weeks after death — nails and teeth fall out.
- 1 month after death — the body starts to liquify.
Stage One: Autolysis (aka The “Fresh” Stage)
The first stage of human decomposition is called cellular autolysis, or self-digestion, and begins immediately after death. As soon as blood circulation and respiration stop, the body has no way of getting oxygen or removing wastes. Excess carbon dioxide creates an acidic environment, causing membranes in cells to rupture. The membranes then release enzymes that begin eating the cells from the inside out.
Pallor mortis (“stiffness of death”) causes muscle stiffening 3-6 hours after death, reaching its peak in around 12 hours. Small blisters filled with nutrient-rich fluid begin appearing on internal organs and the skin’s surface. The body will appear to have a sheen due to ruptured blisters, and the skin’s top layer will begin to loosen. After 3 days, the body begins to loosen back up as bloat and decay begin.
Stage Two: Bloat
Leaked enzymes from the first stages of autolysis begin producing many gases. The sulfur within the compounds that the bacteria release also causes skin discoloration. Due to the gases, the human body can actually double in size. In addition, insect activity will likely be present.
The microorganisms and bacteria produce extremely unpleasant odors called putrefaction. These odors often alert others that a person has died, and can linger long after a body has been removed.
Stage Three: Active Decay
Active decay is the stage after death in which a cadaver loses the majority of its body mass. Fluids released through orifices indicate that it has started. Organs, muscles, and skin become liquefied. When all of the body’s soft tissue decomposes, hair, bones, cartilage, and other byproducts of decay remain. On top of this, Active Decay is also the stage of death that a body is consumed by maggots.
Advanced Decay – During advanced decay, the rate of decay decreases due to lack of left-over cadaveric materials & fluids. Because of this, maggot and insect activity greatly reduces.
Stage Four: Skeletonization & Decomposition
Finally, during skeletonization, all the tissues and muscles in the cadaver have decayed, leaving behind only a dry skeleton. Because the skeleton has a decomposition rate based on the loss of organic (collagen) and inorganic components, there is no set time frame when skeletonization occurs. This also is heavily dependent on the environment in which the skeleton remains. Air, water, and multiple other conditions all play a role in how long the skeletonization and decomposition stage last.
Bonus: 6 Interesting Facts About Human Decomposition
- In 1977, local police showed up to the site of a disturbed grave in Franklin, TN. Investigators found a dug up grave with a headless body, which they determined had died “a year at most” ago, as the corpse was preserved in early stages of decomposition. However, the old-time apparel and dentistry puzzled law enforcement. Upon further examination, it was discovered that due to special embalming methods and advanced casket technology, the body was actually that of Confederate lieutenant colonel William Shy, who died in the American civil war in 1864. The embalming methods and airtight Fisk metal coffin preserved Shy’s corpse for over 100 years, even in the Tennessee climate.
- Embalming and casket technology severely hinders the natural decomposition process. If monitored consistently and accurately, bodies can be preserved for decades — just take into consideration Vladimir Lenin’s body, which has been preserved and on display for over 90 years.
- If left in an environment at a consistent 50 degrees fahrenheit, it will take only 4 months for a body to fully decompose into nothing but skeleton.
- If a body is left out in the sun in a hot climate, bacteria and insects won’t survive very long, meaning the body will only become half-decomposed, eventually becoming mummified and dried up. However, if left in shade in that same climate, the body will be decomposed to the bone as bacteria, animals and insects continue to feast.
- Bodies in water decay differently than those on land. In fact, forensic pathologists can tell if a person was killed before or after they entered the water by examining the lungs. If the person drowned, then their lungs will be filled with water and their corpse will sink in water, becoming a feeding ground for sea life. But if a person was killed and then dumped in water, the body will float because the lungs will still have air in them, causing the rate of decomposition to vary.
What Happens To A Dead Body In Water?
What happens to a body in water is dependent on many variables, just as it is on land. For example, on land, if the climate is right and there’s high potential for insects, vultures or other creatures to feast and thrive, a body can be reduced to a skeleton fairly quickly.
The same goes for body decomposition in water. If the body is submerged in water, flies, land bacteria and other creatures are denied access. But if sea life is present — fish, crabs, sharks, bacteria, etc. — then a body will still be skeletonized quickly. Warm, fresh or stagnant bodies of water will break a body down quicker simply because they tend to breed bacteria and host other sea life willing to feed. However, cold, salty or running water is much more likely to preserve a body for longer.
Cold bodies of water slow the decomposition process, allowing for adipocere (aka corpse wax) to form. Adipocere is a hard, waxy substance formed by decomposing fat mixing with moisture. It covers much of the body, creating a sort of natural embalming that can protect the corpse from further decomposition. Because of this, bodies have been retrieved from cold waters after weeks, remaining in-tact.
How Do The Stages of Human Decomposition Affect The Site of an Unattended or Traumatic Death?
An unattended death, and the accompanying bacteria, mold, and insect infestation, can cause damage to a building’s structure, personal belongings and pets. After a body is properly removed, a professional trauma and crime scene cleanup company should always be called to clean and disinfect the site. And while an unattended death could lead to exposure to dangerous bloodborne pathogens, decomposition itself is a perfectly natural process.
Aftermath takes great care to ensure our sympathetic, compassionate, and discreet teams clean the death site as soon as possible so families can begin the healing process. Contact us 24/7 online or at (877) 872-4339 for further information.
Microbiology Today: http://www.archeo.uw.edu.pl/zalaczniki/upload617.pdf
Compound Interest: http://www.compoundchem.com/2014/10/30/decompositionodour/