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© Bill & Melinda Gates Foundation

The Recipe for Fake Poop

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© Bill & Melinda Gates Foundation

Researchers around the world are working to reinvent the toilet, bringing toilets to the 2.5 billion people worldwide who don't have a safe place to relieve themselves. But there's a slightly gross problem—how do you test a toilet in a sanitary and, ahem, repeatable way?

Enter "fake poop," my preferred term for what scientists call "synthetic sludge simulant." Yes, this is a material meant to simulate fecal matter, and it has to have properties very similar to real fecal matter—minus all the pathogens, odors, and grossness. For this year's Reinvent the Toilet Fair, a new recipe was developed by the Pollution Research Group at the University of KwaZulu‐Natal, South Africa. Their recipe was inspired by a research paper on simulated fecal matter used to test space toilets ("Simulated Human Feces for Testing Human Waste Processing Technologies in Space Systems," SAE Technical Paper 2006-01-2180, 2006, doi:10.4271/2006-01-2180). The Pollution Research Group developed a series of recipes, finally settling on the ninth one. Here's the breakdown of what's in "Synthetic Sludge Recipe Number 9":

1. Instant Yeast

Plain old store-bought yeast packets you'd use to make bread.

2. Psyllium Husk

Seed husks that provide mucilage, described by Wikipedia as "a thick, gluey substance produced by nearly all plants and some microorganisms." You can often buy this in the bulk aisle at grocery stores.

3. Peanut Oil

Just what it says on the tin.

4. Miso Paste

The fermented seasoning used in many Japanese recipes. Available in packet form from grocery stores.

5. Polyethylene Glycol (PEG) 400

PEG is used in all sorts of applications (including skin creams and toothpastes), but if you've ever had a colonoscopy, you'll recognize it as that gloopy stuff you have to drink to, ahem, clear out your system. Well, technically, the colonoscopy prep material is PEG 3350, the number referring to the material's molecular weight as measured in daltons.

PEG 400 is actually available on Amazon, and it's an ingredient in many non-fake-poop products, including inkjet printer ink.

6. Inorganic Calcium Phosphate

Often used as a leavening agent in baking, Calcium phosphate is also used in some cheese products. If you're looking to follow the recipe exactly, you'll want to buy this from a chemical supply company.

7. Cellulose

The recipe calls for cotton linters, a byproduct of cotton harvesting and an ingredient in paper manufacturing. The recipe also includes plain old paper tissue, shredded.

8. Water

What's a recipe without a little water? (Actually, a lot of water -- see the mass numbers below.)

What it Looks Like

The resulting product was "very sticky," according to a person close to the matter. It reportedly has a "vinegar-yeasty smell." Let's just look at a photo of the fake poop being bottled and leave it at that:

Photo courtesy of The Bill & Melinda Gates Foundation.

Putting it Together

Here's the breakdown when it's all put together:

Ingredients % Wet Mass Mass for 1kg % Dry Mass
Instant yeast 7.3 72.80 32.49
Water 77.6 776.10 --
Psyllium 2.4 24.30 10.84
Peanut oil 3.9 38.80 17.31
Miso paste 2.4 24.30 10.84
PEG 2.7 27.20 12.14
Inorganic Calcium phosphate 2.4 24.30 10.84
Cellulose (half cotton linters/half shredded tissue) 1.2 12.40 5.53
Total Mass 100.0 100.20 100.00

This year's fake poop was manufactured by Unilever and donated to the Reinvent the Toilet Fair: India. Unilever also makes the toilet cleaner Domex, and is holding a Domex Toilet Academy aiming to build 24,000 toilets by 2015.

Fake urine, on the other hand, can be less complicated. If you're just testing fluid flow in a toilet, plain old water will work. (For applications involving chemistry, well, let's just say that's a whole different story.) Here's an image from the Reinvent the Toilet Fair showing a little fake urine going in the loo:

Photo courtesy of The Bill & Melinda Gates Foundation.

For a bit more fake poop fun, check out this TEDx Talk by Professor A.J. Johannes, who didn't use this recipe for his fake poop. He said, "Mashed potatoes, curiously enough, are very, very similar [to human feces]. I know, I know."

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How the Global Bird-Poop Trade Created a Traveling Mummy Craze
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Mummy of Christopher Delano; image from the 1864 French translation of the 1854 A Descriptive Narrative of the Wonderful Petrifaction of a Man into Stone. Image Credit: Courtesy of Garrett Scott

Bird poop has been a favored fertilizer for centuries—and, it turns out, is an excellent preserver of human flesh. These two factors came together in the 19th century as the global trade in guano, the excrement of seabirds (or bats), took off, leading to some unexpected travelers coming along for the ride—and raking in the cash.

Guano contains essential nutrients for plant growth and naturally accumulates near nesting areas. Its Miracle-Gro properties were prized and regulated by the Incas (the word wanu is Quechua in origin), but it wasn’t until 1802 that the European world learned of this resource through the writings of Prussian naturalist Alexander von Humboldt, who traveled extensively along the west coast of South America.

By the 1840s, Europe and the U.S. were importing guano for fertilizer. When it was discovered the poop could also make gunpowder, a veritable guano mania began. Guano was soon going for about $76 per ton, and the U.S. imported over 100,000 tons of it in 1861 [PDF]. That's about $250 million in today’s dollars.

In the race to control the world’s guano deposits and secure bird poo futures for its people, the U.S. created the Guano Islands Act in 1856, allowing any U.S. citizen to claim guano-covered islands. Control over guano resources became part of the justification for the Chincha Islands War (1864–1866) between Spain and Peru and Chile, as well as for the War of the Pacific (1879–1883), in which Chile stole Peru’s guano.

In the midst of this fervor for feces, guano miners were hard at work chipping away at the hardened mounds of poo on islands in the Pacific, Caribbean, and Atlantic. Strangely, on some of these islands, among the guano they also found mummified humans.

The most well-known guano mummy is that of Christopher Delano. On the island of Ichaboe, a teeny speck of land off Namibia, a crew of guano miners found a canvas hammock containing a human body under about 6 feet of guano, with a wooden plaque saying “Christopher Delano, 1721.” A cheery pamphlet from 1854 describes his mummified corpse and its travels: “But for the hair and teeth, which were quite perfect, [it] appeared a mass resembling stone, all the natural and component parts, of the body being changed by the process of petrifaction … [and] composed chiefly of lime and ammonia.”

In spite of the quite scientific understanding at the time of both natural and artificial mummification (thanks to early interest in ancient Egypt), even with the knowledge of the formation of adipocere, or “grave wax,” on recently interred corpses, the perception of what guano could do appears to have been wrong. Delano was not “changed into a mass of lime and ammonia.” We know now that in the short term, guano can help seal dead bodies, creating an oxygen-poor and salt-rich environment that is good for preservation. In a warm, arid climate like Namibia, the guano helped dry Delano’s body and shield it from scavengers.

Captain Wethers, who commanded the crew, brought the mummy from Ichaboe to Liverpool, where it traveled to the British Museum. From there, poor Delano went on a tour of Great Britain and Ireland, where he brought in more than $150,000—the equivalent of about $4 million today.

Upon examination of Delano, British and French scientists determined that he was European and not African, and the amount of wear on his teeth suggested he was in his mid to late 30s when he died. His right shoulder is elevated and contracted, and his open mouth revealed “a death of agony” (though it's not unusual to see a gaping jaw on a mummy). His cause of death? Likely a spear wound to his right shoulder.

The writer of the 1854 pamphlet took liberties with the sparse facts available: “About 1721, the Island of Ichaboe had been the resort of nests of Pirates…. In all human probability, the most satisfactory conjecture that can be arrived at is that the unfortunate Christopher Delano was a Spaniard, joined in some piratical enterprises, and leagued with a gang of desperadoes, from one of whom, while visiting the Island of Ichaboe, he most probably received his death wound in some bacchanalism origies [sic] or sudden quarrel.”

With this amazing manufactured backstory, Delano’s body was brought to Philadelphia and exhibited before being shipped to France by the mid-1860s. Although billed as the “only one in the world” and “the solitary known example in the Universe of its kind,” it was only a matter of time—and feverish digging—before more mummies preserved by bird poop materialized. Just a few years after Delano was discovered, the British ship Octavia also docked in Liverpool with a load of guano—and the mummies of a man, woman, and child from Peru [PDF]. Like Delano, they were eventually exhibited at the British Museum in London.

In 1868, British natural historian Francis Buckland noted that he saw yet another guano mummy in a “penny show” in Edinburgh; according to the show's handbill, the body was brought from Possession Island off the west coast of Africa by Captain Dunlop’s ship Echo. The mummy was well preserved, with an oaken board that was carved “Peter Creed, 1790.” Buckland spoke with the owner, who reportedly announced that the mummy “is as good as a pension to me,” earning him today’s equivalent of $2000 in under two weeks. The owner was aware of the Delano corpse, which at that point he claimed had disintegrated due to its travels, but mused “he ain’t no use as a scientific mummy now; the more’s the luck for me as long as my Peter Creed holds together.” (Given England’s humidity, though, it is doubtful that his Mr. Creed survived for very long.)

By the early 20th century, the guano trade had tapered off. Industrialized countries found new sources of fertilizer, and it turns out that guano was not a very good source of saltpeter for gunpowder. Many islands and atolls had been completely stripped, but the legacy remains: Many remain in U.S. possession after being claimed for their guano 150 years ago. Seven of these make up the Pacific Remote Islands Marine National Monument, the world’s largest marine reserve. As for the islands that produced Delano and Creed, these today support Cape gannets and endangered African penguins, and wildlife conservationists still often visit to monitor these populations.

While guano mummies are occasionally discovered in these areas, today new finds are largely made by archaeologists excavating prehistoric caves sites in arid locations like Nevada, New Mexico, and Durango, Mexico. Still, with the popularity of bat guano as an organic fertilizer on the rise today, it’s likely more poop-preserved mummies may yet turn up.

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A Smelly Bike Locks Drives Thieves Away By Making Them Vomit
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There’s no city that’s safe from bike thieves. A 2014 survey found that half of cyclists will at some point have their bike stolen. So what’s a cyclist to do when even the best U-lock can’t deter a serious thief? A pair of inventors thinks bad smells are the answer, The Guardian reports. The crowdfunded product SkunkLock looks like a regular U-lock, but if someone tries to break it, it releases a smell so vile that the thief is left puking.

According to the company, when the lock is breached, it emits a non-toxic but terrible formula—like pepper spray, its active ingredient is capsaicin, the compound that makes chili peppers spicy—that makes it difficult to see or breathe without vomiting. (SkunkLock swears it’s legal, but it still has to go through some legal vetting before the product can ship.)

Presumably, the puking thief would then flee the scene without the bike. The lock doesn't prevent a good lockpick from making off with your bike and your intact SkunkLock, but it will at least punish opportunists wielding bolt cutters.

It’s not the only useful application of disgusting odors. The vile-smelling spray Liquid ASS is used in military training to expose soldiers and medics to the horrible smells of war.

SkunkLock is taking pre-orders for $99 on Indiegogo.

[h/t The Guardian]

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