Everyone dies. It's kind of a bummer but it's inevitable. Humans have entire
philosophies and religions dedicated to the contemplation of what happens once our
bodies stop working, but unless you're a mortician,
how much thought do you give to what happens to your flesh and blood after
you die?
Will it be burned up, buried underground, frozen, probed by queasy medical students
or even displayed in a museum?
These days - once you're dead you actually have a lot of options with
more on the way. No wonder the US funeral services industry is a twenty
billion dollar business. And whether you're into the idea of a jazz funeral,
Viking burial or a 21-gun salute, once the ceremonies are over,
there are some choices to make. Some options are simply honored by tradition,
others are designed to let your body have the least impact on the world
that's becoming increasingly overpopulated with corpses. Most of these
options are legal and some
are a little bit creepy.
So, dead bodies.
Biologically speaking, as soon as the heart stops beating, cells stop receiving
oxygen and start to die.
Your brain cells go first but skin and bone cells can live on for
several days. Blood starts to pool in lower lying areas as your capillaries drain.
After a few hours rigor mortis sets and as muscle suddenly stiffen
possibly scaring the bejesus out of bystanders
and within 24 hours, the body will have lost all of its internal heat
in a process called Algor mortis which, yeah, sounds kinda like Voldemort curse there.
The enzyme in bacteria-laden pancreas begins to digest itself before these
hungry organisms start to spread to other organs.
Things start to get smelly and bloated as the bacteria produce strong gases.
Hopefully by now, the body has been put on ice or is getting processed for its
final fate and, like I said,
there are many and actually surprisingly varied final options.
Back in the day, swiftly burying a corpse helped prevent the spread of disease and
it also helped mourners psychologically to remove the body from view.
Archaeologists have found multiple Neanderthal burying sites
indicating that the need to ritually dispose of corpses is a deeply seated
hominid need. Just laying a body in the Earth and covering it is a pretty good
way to let decomposition do its thing.
It's kinda the ultimate composting but with population growth and the urbanization in
many countries, burial
has gotten a lot more complicated. Mainstream Western burial is now very
resource-intensive involving an embalmed body placed within a reinforced coffin
buried with vault of cement.
That doesn't do much for timely decomposition - it also takes up a lot of
space underground. Now, the act of trying to preserve a body is nothing new. The
Egyptians perfected mummification centuries ago using salty powders and
resin.
And it also doesn't hurt that Egypt's climate is naturally, you know, dry
But modern embalming developed during the Civil War to transport bodies of dead
soldiers is different than mummification chiefly because it doesn't preserve a
body indefinitely and
because it uses lots of nasty chemicals. Embalming fluid is typically a
mixture of formaldehyde, methanol and other solvents. It preserves bodies by
irreversibly denaturing basically changing the shape
of cell proteins so that they're no longer a food source for bacteria
and also by killing the bacteria that are there. It's estimated that the United
States cemeteries alone bury over three million liters of toxic embalming
fluid every year
not only that but we've got an estimated 90,000 tons of steel, 1.6 million tons of
concrete nearly seventy one thousand cubic meters of hardwood going into
the ground each year. But even if the body is buried without all that stuff
if it's much deeper than 50 centimeters, the decomposition process must carry on
without the benefit of oxygen. This process of anaerobic digestion means
that instead of producing carbon dioxide and water as it would in the open
air or in topsoil, a body just kinda turns to sludge and leaks methane
so-called natural or unembalmed burials are on the rise in England foregoing the
chemicals in concrete and instead burying bodies in shrouds or
biodegradable coffins
so they can naturally decompose. But if the thought of your body remaining in a
bunker underground for decades to come isn't so appealing and your religious
views don't prevent it perhaps you'd rather end up as
ashes or fine gravel size bits of crushed bones as it were.
Humans have been cremating their dead since prehistoric times - it's the
mandated last
right of Hinduism - but the first modern crematoriums didn't show up in
England and America until the late eighteen hundreds. While funeral pyres and
shooting flaming arrows into boats at sunset seem to work well enough,
modern cultures have found ways to standardize and sterilize the process.
Today a body is kept cool until the time of
cremation when it's placed in a flammable coffin and rolled into an incinerator that
reaches temperatures of over a 1000 degrees Celsius.
I'll spare you the particulars of what jet engine flame does to flesh and
muscle
but in the end, the heat is intense enough to deteriorate bones until they
begin to crumble.
The whole process usually takes about three hours and leaves loved ones
typically with one to four kilograms of remains.
Today about 41 percent of Americans choose cremation over burial, and while
cremation may be cheaper or more spiritually appealing,
it's only marginally, if at all better, than traditional burial in terms of
environmental impact. It doesn't require as much physical space as full body burials
but believe it or not, all that burning releases compounds like dioxin,
hydrochloric acid, and carbon dioxide into the atmosphere.
In the UK an estimated 16 percent of mercury emissions come from cremated
vapor of dental work. It also takes loads of energy to super heat a furnace for
three hours as in it's estimated that just one year worth and cremations
in the US consumes as much power as it would take
to go to the moon and back over 80 times. Once you're left with an urn full of
ashes you've got various options: you can bury them in the family plot, keep them
on your mantle, or scatter them in a favorite spot.
But you can also have your ashes launched into space or mixed with cement and sunk
into the ocean as an artificial reef.
Legendary journalist Hunter S Thompson had his remains packed into fireworks
and shot out of a cannon.
If you wanted the keepsakes, there's a company that will use your ashes to make
pencils - yes apparently the average human body yeilds enough
ashes to provide graphite for 240 pencils.
Or you can turn those remains into a diamond through intense heat and
pressure which gives a new meaning to the term
heirloom jewelry. Now if the thought of burying or burning your body doesn't appeal what about
being liquefied? Alkaline hydrolysis uses an extremely alkaline solution to
liquefy bodies;
people have been using it to safely dispose of diseased livestock for years.
In this process a corpse is
zipped into a silk bag, placed with an assorted mesh
cage, and loaded into a pressurized device. Once sealed, the chamber is filled
with water and potassium hydroxide, also known as lye,
a key ingredient in many liquid soaps, and then heated under pressure to 180
degree Celsius. It takes about three hours for the super corrosive concoction
to reduce a body to mush, or more specifically, a greenish brown
oily juice made up of amino acids, sugars, and salts. Once that liquid seeps
out, it can pretty much just go down the drain or if you're more poetic, say, put into
a garden. What's left of the calcium phosphate bones can be crushed to dust
in your hand then scattered or buried wherever you please just like ashes.
The whole process uses far less energy than cremation, releases no greenhouse
gases or mercury vapors and unlike traditional burial requires very few
resources. Currently this practice is only legal in a handful of states,
though it's used by the Minnesota Mayo Clinic to dispose of donor bodies,
it's a promising alternative to burial and cremation, if you can get past the whole
puddle of green goo part. But perhaps you prefer the idea of ice
over fire then maybe the emerging practice of promession will hold some appeal.
Remember in middle school when your science teacher busted out the liquid nitrogen and
shattered a banana or a rose or something and it blew your mind?
Well that's pretty much half of the promession process. Developed by a Swedish
biologist promession begins by freezing
a body in a vat of liquid nitrogen. This makes the body so cold it becomes brittle
then a low vibration is applied and the body slowly crumbles
into dust. A special vacuum then runs over the remains removing the ice and
evaporating the water. What remains is a powder that weighs 50 to 70 percent less
than the original body.
From there any tooth fillings, fake hips, and Bionic knees are removed
and the remaining human dust is tucked into a biodegradable casket
and laid to rest in a shallow grave. From here, anaerobic bacteria can work their
magic and compost the remains within a year.
At least that's how the theory goes - Swedish company Promessa has tested
the concept using pigs, but it has yet to be put in practice on humans.
Now if your of the mind that the dead body still has a good use or two left in it you may want to
consider donating your body to science or education.
Temporarily preserved bodies can be used for lab dissections in medical procedure
practices, or if you end up being preserved for all time and displayed in
a museum exhibits like Body Worlds,
you could look into plastination. Developed by a German anatomist in the
nineteen eighties the plastination process replaces a body's water and
fats
with plastics such as a epoxy and silicone, leaving hard,
sturdy specimens that don't smell or decay and that can be shaped into one of the
many dance positions from Thriller.
So between being burned, buried, frozen, liquefied, or plasticized and put on display,
a corpse has a lot of choices these days and if you try to live your live in an
environmentally sustainable way,
you can extend that priority through your death, if that's your jam. Thank you
for watching this particularly morbid infusion shot in the Keith Chiem studio
and thank you to all you Subbable subscribers for your continuing support
of SciShow
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