What Connects Bones, Bird Poop, and Toxic Green Slime? Hint: Without It, Half of Us Wouldn’t Be Alive Today

It’s the 13th element on the periodic table, it glows in the dark, and it spontaneously combusts if it gets any hotter than 80 degrees Fahrenheit; little surprise, then, that phosphorus is known as “the devil’s element.” But this satanic substance is also essential to all life on earth, which is why it's a key ingredient in fertilizer—without which, researchers estimate, we could only grow enough food for half as many humans as are alive today. The incredible crop-growing powers of phosphorus have led humans to do some pretty extreme things to get it—from seizing Pacific islands to scavenging bones from Europe’s most famous battlefields—but they’ve also created a devilish paradox. The world is running out of phosphorus, and yet there’s way too much of it running off farm fields into rivers, lakes, and oceans, where it fuels toxic algae blooms. This episode, we've got the story behind the phosphorus paradox, as we ask: is there any way to fertilize the planet without sending it to hell?

Episode Notes

Dan Egan

Award-winning environmental journalist Dan Egan is the author of The Devil's Element: Phosphorus and a World Out of Balance. He is currently the journalist in residence at the University of Wisconsin-Milwaukee's School of Freshwater Sciences.

Lake 226, one of the lakes in Ontario that scientist David Schindler famously divided to test the effect of fertilizers on aquatic communities. The lake in the bottom half in this image has been dosed with phosphorus, fueling an intense algal bloom. (Image courtesy of the IISD Experimental Lakes Area)

The Alfred P. Sloan Foundation for the Public Understanding of Science, Technology, and Economics

This episode of Gastropod was supported by a generous grant from the Alfred P. Sloan Foundation for the Public Understanding of Science, Technology, and Economics. Check out the other books, movies, shows, podcasts, and more that they support here.


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