Sciencemadness Discussion Board - Decomposing corpses

Decomposing corpses

mycotheologist - 1-5-2012 at 05:59

I watched the film Me Myself and Irene (one of the funniest films I've ever seen), and theres one part where a corrupt detective has a shovel and a big bag of lime in his trunk which he was planning on using to dispose of their corpses after he killed them. Firstly, what exactly is lime, I know that the word refers to calcium salts in general but in this case would it be calcium hydroxide? I'm guessing they sell big sacks of it like that in hardware shops for building or agricultural purposes. Would lime really accelerate the decomposition process all that much and kill off any bacteria that would ordinarily make the process stink (by decomposing amino acids into cadaverine and putrescine)? I doubt that would be very effective because the bacteria would start to decompose the corpse from the inside, before the lime would have time to corrode the skin and muscles etc. Then again, I don't know how long it would take for Ca(OH)₂ to burn through skin, I've had NaOH on my skin before and within minutes, the tingling sensation, turns into a burning sensation and leaves you with mild chemical burns so given days, it'd probably do some serious damage but thats NaOH, not Ca(OH)₂.

In an episode of Breaking Bad, they used hydrofluoric acid to completely melt 2 corpses, which I found pretty cool and if I ever had to dispose of a corpse, that'd be the method I'd opt for. Like that, you could just neutralise the excess acid then flush the sludge down the toilet. That would be a pretty horrific way to dispose of a corpse though lol. To prevent natural decomposition, you could inject the body with embalming fluid (i.e. formaldehyde) then do whatever it is they do to permanently preserve animal corpses for museums and stuff like that. In fact, rather than pouring the acid or base, onto the corpse, it would be way more effective to first inject it into the arteries/veins, that way it travels throughout the body and starts decomposing it from the inside. I realise how morbid this thread sounds but when you think about it, its just biochemistry.

ScienceSquirrel - 1-5-2012 at 06:15

Lime has the effect of embalming a corpse if it is packed in to it in a dry place.

Hydrofluoric acid is pretty ineffective for dissolving a corpse but sulphuric acid is excellent.

http://en.wikipedia.org/wiki/John_George_Haigh

MR AZIDE - 22-5-2012 at 10:46

A corpse can be completely digested to the bone in simple household biological washing powder solution in a bath.
Ive seen it done on a UK factual science program years ago........they used bits from a dead pig.

Only snag is, , you need to keep it at about 40' to 50' C for the enzymes to work, and I think it took about a week to remove all the flesh to bone.

[Edited on 22-5-2012 by MR AZIDE]

malcolmf - 22-5-2012 at 11:06

I've always had my doubts about quicklime: not alkaline enough to do serious protein and fat hydrolysis on the scale you'd need, and the suspicion that you'd wind up with a body encased in very poor quality concrete. Bodies pickled in an acid peat bog, or in a sealed lead coffin, keep for decades, if not centuries, so a bit of alkaline buffering might be helpful for decay. (but evidently not enough to help <a href="http://en.wikipedia.org/wiki/Hawley_Harvey_Crippen#Doubts_regarding_the_verdict">Crippen</a>

Strong acid's best, but Haigh found out the hard way that it doesn't destroy gallstones.

bahamuth - 22-5-2012 at 11:30

The best tissue lysis solution I have been working with is hot ethanolic KOH, dissolves a burger meat patty , 150 g or so, in just a couple of minutes and leaves a totally clear amber solution.

Then one would end up with bones which should be calcined and dissolved in hydrochloric acid. Calcination at 600 degrees Celsius removes any phosphates so one is just left with acid solubles, but at this point it is just ash so why not just fertilize the lawn with it...

Lime/quicklime is used to retard the decomposition, rendering the crime guys unable to estimate time of death effectivly destroying a potential link to the victim by time. In war zones or plague zones lime is used to retard the decomposition in mass graves as to not create a septic pool of decomposing humans. In addition, identification of the bodies is possible years after the burial with this method.

Adas - 22-5-2012 at 12:30

What about protheolytic enzymes like sanguinarine? Wikipedia states that is is very corrosive on skin contact.

Formatik - 22-5-2012 at 13:55

There was a topic like this before: http://www.sciencemadness.org/talk/viewthread.php?tid=11741

Quote: Originally posted by mycotheologist

I've had NaOH on my skin before and within minutes, the tingling sensation, turns into a burning sensation and leaves you with mild chemical burns so given days, it'd probably do some serious damage but thats NaOH, not Ca(OH)₂.

Dramatization.

bahamuth - 22-5-2012 at 14:30

Hmm, I can't view that thread for some reason..

Anyways, can you Adas give the link to the enzyme, as I only can find the alkaloid on wiki or anywhere..

If one would tape a NaOH pellet to ones skin and leave it for a couple of hours I can assure you a 1 cm diameter hemispherical painful hole of lysed tissue that will not heal for months.

The thing with strong bases is that they saponify the tissue, thus generating detergents of your lipids that will continue to dissolve the lipid membranes of your cells and so on generating more "soap" to destroy the lipid membranes.

Acids on the other hand, only protonates and the acid anions are usually not toxic and is just removed by the body or bind to the now free amino acids and do minimal harm.
Strongly dehydrating acids like concentrated sulfuric acid gives the same effect as a thermal burn, and some chemical burn from the acid itself.

The most tissue lysing acid I ever come across is trichloroacetic acid, as the pure compound gives chemical burns instantly, as opposed to sulfuric which has a slight delay IMO (you know the strange feeling of increasing heat formation when your whole hand is covered in 1.84 d sulfuric acid

).

Another defence against acids is the lipids themselves, not being soluble in most acids and thus protecting further penetration of the tissue.

In DNA extraction we use proteinase K (K for keratin) and have always wondered if it would lyse me if I put some under a piece of tape for hours, though I suspect my own enzymes would finish it off kinda quickly...

Additionally, a story of the tissue lysing properties of NaOH. While I was cleaning beakers from the sulfuric acid/sucrose dehydration carbon snake experiment that two of my classmates constantly was doing for fun as part of their retardedness (they were actually retarded, and only put in that class as to get the funding to keep it going another year..) I found that strong NaOH/water at boiling temperatures would clean them in a jiffy, and to contain the corrosive fumes I had just a watchglass covering the beaker (600ml IIRC) and as I was lifting it off the hotplate the watchglass ( a couple off mm bigger in dia. than the beaker rim) was lifted slightly "more" than the beaker (was lifting from the top, remember the beaker contained boiling NaOH/water over 100 degrees C., and the top was the coldest part) and a superheated steam/NaOH vapor ate through my thums skin in just a second or so, leaving me with only the lower leves of dermis intact and the outer layers almost completly decomposed, white and crumbling....

Endimion17 - 22-5-2012 at 14:42

Quote: Originally posted by bahamuth

...

and a superheated steam/NaOH vapor...

Say what?

bahamuth - 22-5-2012 at 21:42

Quote: Originally posted by Endimion17

Quote: Originally posted by bahamuth

...

and a superheated steam/NaOH vapor...

Say what?

Well not pressurised of course, but steam way over the 100 degrees C water boils at, was so hot that it didn't condense into visable droplets before it was "far" from my hand and beaker. Like a coffe kettle at extreme boil, when you see the water gas jet is transparent far from the tip of the kettle before it is cold enough to condense into visable droplets.

If you ever boiled a strong solution of NaOH water you know that it passes some NaOH with the vapor by the chocking feeling and the ammonia smell in ones nose from the hydrolyzed mucus.

Endimion17 - 23-5-2012 at 00:48

Quote: Originally posted by bahamuth

Quote: Originally posted by Endimion17

Quote: Originally posted by bahamuth

...

and a superheated steam/NaOH vapor...

Say what?

Yeah, droplets that spray around, but the vapor shouldn't contain more than traces of lye.
I'll try to repeat it, it sounds interesting. Not the skin dissolving part.

kuro96inlaila - 23-5-2012 at 03:34

I wonder how corpses react with piranha solution,maybe the most fast way to eliminate the flesh..........

weiming1998 - 23-5-2012 at 04:52

Quote: Originally posted by kuro96inlaila

I wonder how corpses react with piranha solution,maybe the most fast way to eliminate the flesh..........

There is a risk of explosion, and still would not be as fast as hot, concentrated NaOH solution. I dropped a piece of cooked meat in it before and it disintegrated within seconds, releasing a bad smell. I don't think raw meat would take much longer. Piranha solution destroys flesh via direct dehydration oxidation of it to CO2, while NaOH hydrolyzes the fats and deprotonates amino acids and DNA. The only problem is the immense stench that is easily noticeable.

bbartlog - 23-5-2012 at 06:28

Having buried a number of animal corpses (turkeys, a raccoon, four chickens) in my attempt at a nitre bed I can say that it does an excellent job at containing the odors. I'm guessing that a large portion of the stench that decomposing flesh creates is ammonia, and that the nitrifying bacteria will if given the opportunity turn that ammonia into odorless nitrites. I would speculate further that one of the reasons for burying bodies with lime is that it keeps the pH high enough for nitrosomonas to operate.

Adas - 23-5-2012 at 07:10

Sorry, my bad, I didn't mean to write EMZYME, but ALKALOID. But it is too hard to get in larger quantities

Sedit - 23-5-2012 at 18:33

What about Fentons reagent? It has a pretty good tendency to destroy organic material in a violent reaction so has anyone ever attempted to destroy flesh with it?