A wave of human bodies that mysteriously do not decompose after burial is causing a crisis in Portugal, where corpses have been observed to mummify naturally after burial.
According to local space-saving laws, corpses must be exhumed regularly so that skeletal remains can be placed in smaller containers.
But many simply do not decompose, traumatizing families whose loved ones are repeatedly discovered only to be relocated to continue to decompose.
A fundamental problem is that no one really knows what happens to corpses buried in coffins.
Scientists in Portugal are now working to uncover the cause of the strange mummifications.
Grave recycling to combat overpopulation
Faced with drastic overcrowding in its cramped urban cemeteries, Portugal introduced the concept of temporary graves in the early 1960s.
The idea is simple: A decomposed body takes up less space. The bones can be packed into a smaller casket and moved to a less spacious final resting place, such as special drawers in the walls of cemeteries.
“We don’t have space to create new cemeteries or upgrade cemeteries that already exist” in cities, said Angela Silva Bessa, a forensic anthropologist at the University of Coimbra who studies Portuguese cemeteries.
Bodies that refuse to rot
Three years after the burial, the family of the deceased may often receive a letter warning them that the remains will need to be moved soon.
By law, the body can only be moved if it has decomposed to a mere skeleton, with no soft tissue remaining.
To check this, gravediggers have to dig up the body to see it. If it doesn’t decompose enough, it is buried again and the process is repeated every two years until it does.
A survey of cemeteries in Porto, Portugal’s second largest city, found that 55 to 64 percent of bodies between 2006 and 2015 had not fully decomposed after they were first exhumed.
Paulo Carreira, funeral home owner and CEO of Portugal’s national funeral association, told Insider that families usually cope very well the first time.
But repeated disclosures can be very emotionally damaging.
In some cases, it can take decades of repeated burial and reburial before the body reaches its final resting place, according to Carreira.
And for a subset of these bodies, the process is essentially endless: They are mummified.
Unlike the Egyptian mummies, which were preserved on purpose, this happened spontaneously. Natural mummification usually occurs when a body dries out so quickly that decomposition simply stops. It has been observed in extreme environments such as deserts or glaciers, or in extreme heat and cold.
Why so much happens in Portuguese tombs has so far proved elusive.
A quest to understand death
Silva Besa and her colleagues investigated what could be slowing the decay of these bodies in Portugal as part of her PhD thesis, a first-of-its-kind study.
With the consent of the families, he collects samples of corpses and the soil around them from five cemeteries.
“It’s pretty amazing,” he told Insider. “In the same part of the cemetery I have different stages of decay.”
Some bodies are fully skeletonized while others are still decomposing, he said. Others will be mummified from head to toe.
“Even in the same body, I might have the whole body skeletonized, the pelvic area rotten and the hands mummified. So you can find a little bit of everything,” he said.
Silva Bessa looked at eight soil properties that may affect decomposition, including temperature, acidity, moisture, density, heavy metal contamination and organic matter.
So far, he has yet to make a breakthrough. “I honestly thought I would at least find a relationship between soil properties and body composition status,” he said, “And I didn’t.”
Her next step will be to test whether substances people took in their lives, such as whether they smoked or took certain medications, could be a factor.
The decomposition of the body is still mysterious
Tristan Krap, a lecturer in forensic science who studies the decomposition of bodies at Maastricht University in the Netherlands, said he was not surprised that the bodies did not fully decompose within three years.
He said he would expect a “normal body” in a grave to take about five years to decompose, although he admitted it was mostly guesswork.
Scientists like Krap use facilities that have access to donated bodies to study decomposition, so-called body farms.
But these tend to focus on what happens to the body above ground, which is useful for cases like homicide investigations, but less useful for understanding regular burials.
Much less work examines what happens to the body after it has been buried in a grave, which is likely to be much more complex.
The body is like “a huge biological bomb,” introducing bacteria, tissues and various juices into the soil, which has a complex ecosystem, Krapp said.
One factor, Krap said, could be variations among people’s bodies such as overall size, muscle mass and fat levels.
You can read more about the decomposition process here.
A lasting impact on culture and grief
“This has a social impact, which is very big for my country,” Silva Besa said.
Faced with a shortage of graves, people have turned to cremation, Carreira said, and his business has adapted along the way.
“Fifteen years ago we had four crematoria. Today we have 38,” he said.
To an extent, it works – if they were all cremated, there wouldn’t be a problem.
But, as Silva Besa noted, for the Portuguese “it is the tradition to bury the corpses so as not to cremate them”. And for now, lack of space and a yawning gap in science squeeze it out of existence.
For now, she continues her work, determined to find a parameter that might help.
This article was originally published by Business Insider.
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