How long does it take for human remains to become bones after burial?

When a human dies, various changes occur in the body tissue, decomposition progresses, and eventually it returns to nature, but various factors are at work in that process. Scientific media Live Science summarizes the question 'How long does it take for human remains to become bones after burial?'

How long does it take for a body to decompose? | Live Science

When a human dies, the blood circulation in the body stops, and the cells begin to die due to the lack of oxygen supply to the cells. After that, the degradative enzymes contained in the lysosomes are released from the cells, and the proteins and lipids are decomposed to soften the tissues and cells, a process called autolysis .

Furthermore, decomposition progresses due to the action of anaerobic bacteria , fungi , and other organisms, and about 18 hours after death, part of the skin begins to turn green. At the same time, intestinal bacteria proliferate rapidly, producing gas, a distended abdomen, and unpleasant odors. These postmortem changes progress faster in hot places, so if there is time until burial, the corpse is kept in a refrigerator or cooled with dry ice.

During the putrefaction stage, putrid blisters form on the surface of the skin, and blood sinks under gravity to reveal niches that look like bruises. In addition, about 24 to 48 hours after death, greenish-black blood vessels can be seen through the skin. is said to remain. If only the skeleton is used, the rate of decomposition will be significantly slower, and it will take several years to several decades for the bones to collapse.

However, in countries and regions with many Muslims and Christians, burial is common even today, and

embalming is sometimes applied to delay the decomposition of the body. Basic embalming involves draining the body of fluids such as blood and injecting an antiseptic treatment solution to stop the activity of bacteria that break down the body. ``If the corpse is embalmed, the course of decay will be completely changed,'' said Daniel Wescott , director of the University of Texas Center for Forensic Medicine and Anthropology.

Mr. Wescott pointed out that the body of Evers was exhumed for evidence during the 1991 trial for the murder of civil rights activist Medgar Evers , who was killed in 1963. Evers's body was so well preserved that it had been embalmed, and excavators were able to bring Evers' son face-to-face with it.

If the embalmed body is buried in a coffin, the decomposition process is much slower, so it will take 5 to 10 years or more to become only the skeleton. However, in the excavation survey of the corpse buried 15 years ago when Mr. Wescott attended, it seems that part of the coffin was broken and it was partially skeletonized. If the soil in which the coffin is buried is acidic, the coffin will erode faster than usual, making it easier for insects that accelerate the decomposition process to enter.

The condition of the corpse itself also affects the rate of decomposition. For example, when obese bodies are placed outdoors, the early stages of decomposition progress faster than lean bodies, but the latter half of the decomposition process is slower than lean bodies because maggots prefer muscle tissue to fat. Also, chemotherapy and antibiotics kill some of the bacteria involved in the decomposition process in corpses that had been battling disease before they died, which can slow down the rate of decomposition.

Wescott also points out that coffin lining can also affect the rate at which a body decomposes. For example, if the coffin material is dry, it will draw water out of the corpse and dry out faster, making it easier to mummify. On the other hand, if the material retains moisture, the corpse may be immersed in the moisture it exudes and decompose more quickly.

in Science, Posted by log1h_ik