For a while one my daughters’ favorite books was What Do They Do With All The Poo From All The Animals At The Zoo? It’s a fun(ny) book. How can it not be. It hits my four and 2.5-year-old right in the tickles.
But, seriously, what do we do with all the poo? The human kind.
Listen. Lina Zeldovich has some eye-opening scatology over at Aeon:
An average adult produces about a pound (or half a kilo) of poo a day. That means that New York City, with its official census population of more than 8 million, pumps out more than 8 million lbs (or 4 million kg/4,000 tonnes) of excrement a day. Tokyo surpasses that slightly with 8.3 million lbs daily. China’s capital Beijing, a huge urban conglomerate of 21.3 million dwellers, beats NYC and Tokyo combined. Now imagine the mind-boggling piles of excrement that the planet’s 7 billion people generate in just 24 hours. Multiply it by 365 days a year, and it will likely make you gasp: Holy crap!
What do we do with all this poo? For the most part, we try to distance ourselves from it as much as possible. The exact mechanisms of that process depend on where you live. In the Western world, we flush it down the toilet. In the less fortunate places, it’s left to decompose in pit latrines or underneath trees. But no matter the country or the culture, the common thread is that we try to move our ordure as far away from us as we can. We’re universally disgusted by it. It’s excrement. It’s yucky by definition. It’s appalling by sight and smell.
Her essay isn’t about the cholera, dysentery and intestinal worms that emerge when populations can’t properly dispose of human waste, although there’s that. Instead, it reimagines or, better, reintroduces us to what could be done with human waste if we had the stomach for it.
It also clues us into a concept: metabolic rift. With it, we trace the extraction of nutrients from one part of the world and the introduction or disposal of those nutrients to another. Basically, modern agriculture is redistributing nutrients – nitrogen, phosphorus and potassium – from one part of the world to another. This leaves soil exhausted where food is grown. And leaves lakes, rivers and oceans choked with algae blooms and decay where it’s eventually deposited.
From Zeldovich:
[B]ecause we don’t ship our shit back to where the food comes from, we keep perpetuating the redistribution of nutrients on the planet. Soils grow barren, so we use synthetic fertiliser, which isn’t anywhere near as good as the real shit, and also is very polluting to produce. In our quest to rid ourselves from our dangerous dark matter, we’ve broken the essential rules and laws of Mother Nature. By taking our poo out of the equation, we altered not only our agriculture, but the entire planet’s ecology.
It’s an interesting read. It’s one that touches on her family’s Russian farm, to how different societies collected human feces in the cities to be brought back out to the fields.
More important, and topical, it’s a call to action for contemporary society to rethink its relationship with human waste as we evaluate solutions for global food distribution in light of its negative environmental effects.