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Human waste: Everything you ever wanted to know

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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We take it for granted, the humble commode, but waste disposal as we know it may not survive indefinitely.

Lucky for us, author Rose George fills us in on the history of the toilet — and the forces that necessitate its upgrade — in her new bookThe Big Necessity: The Unmentionable World of Human Waste and Why It Matters.

In a package of stories, we've excerpted the chapter on Japanese pissoirs, devices that wow many incredulous Western travelers who can't get over their multiple flush settings, ability to take your blood pressure, and toasty seats made warm by a heating mechanism, not another user's rear end. 

But there's a serious discussion to be had about the dearth of poor sanitation, let alone Americans' deprivation of Japanese "robo toilets" (except at trendy New York restaurants): 2.6 billion people around the world have no commode, George tells ScientificAmerican.com's David Biello. The result? Six-thousand children die every day from diarrhea.

In countries where toilets are rare or nonexistent, "sanitation foot soldiers" try appeal to folks' sense of pride or disgust to build a latrine, George tells Biello. But the United States has its own problems with waste-contaminated water: In 1993, more than 100 people died from cryptosporidium, a microbe that causes diarrhea, after Milwaukee's clean-water system broke down. Now, Biello explains, the city has a deep-water tunnel to prevent wastewater from spilling into Lake Michigan — part of a $3 billion water pollution initiative. Check out our slide show of the tunnel.

Clean water isn't the only challenge for waste disposal. Water shortages are becoming more pressing. For those of us who don't live by the maxim, "if it's yellow let it mellow, if it's brown, flush it down," we may need to invest in low-flush toilets that use less water or the vacuum types found on airplanes to get around the water supply issue, George says.

Think you can escape the ripple effects of the toilet by buying bottled water? Think again. A new report from the Environmental Working Group found 38 chemicals in 10 widely sold brands, as well as bacteria, caffeine, drugs, fertilizer and solvents — and you can bet most of that came from human waste that sewage treatment plants couldn't take care of. The companies that make the two brands identified in the report as having chlorine levels exceeding California standards, Wal-Mart and Giant Foods, defended the quality of their water, the Associated Press reports.
(Image by iStockphoto/Drew Hadley)