The trouble with Phosphorus

Phosphorus is a vital element for producing food around the world. Now its price is rising and there’s concern about both scarcity and pollution. Jori Lewis traveled to Morocco to look at the problems and opportunities surrounding this key ingredient in the global food supply.

David Vaccari teaches environmental engineering at Stevens Institute in New Jersey. He explores the cycles of nitrogen and carbon, two elements that are vital for agriculture. There’s a third that’s just as important, but Vaccari never thought much about it until several years ago—phosphorus.

“Suddenly I said to myself, where’s this come from?” Vaccari says. “We didn’t think about it. Nobody talked about it. I even once asked a farmer friend where does phosphorous come from, and his answer was Agway. He didn’t even know.”

So Vaccari did the natural thing. He Googled it. That’s when he learned that most phosphorus used in fertilizer comes from mines, and that unlike carbon and nitrogen, it’s a very limited resource.

“Up popped an analysis that there was a possibility we would use up those known reserves in a century, a lifetime,” he says. “I found that alarming, and I started to study the issue.”

What he learned brought him across the ocean to the Kingdom of Morocco, to the Khouribga mine in Morocco’s phosphate plateau where machines the size of a ten-story building digs massive holes into the earth. In each drag, they unearth about 100 tons of sand and rock to expose the phosphate rock below.

Phosphate rocks are minerals that are high in phosphorus. Along with sun, water, carbon and nitrogen, phosphorus is indispensable to agriculture—all plants need it to grow, so it’s a key part of many chemical fertilizers. Most of the other ingredients in fertilizer are abundant and easy to produce, but phosphorus is much less common. A few years ago, some scientists sounded the alarm that phosphorus supplies were getting tight. Forget peak oil, they said, what we really need to worry about is peak phosphorus, because without it, we can’t produce food.

It turns out that phosphate rocks occur in significant amounts in only a handful of countries. And Morocco has the mother lode—more than two-thirds of the known reserves worldwide. As those reserves have been drawn down elsewhere, the world is increasingly coming to Morocco, and the country is responding by building huge phosphorus mining and processing operations.

Morocco’s state-owned phosphate company OCP has made plans for what it calls “massive” investments–$15 billion over the next 10 years, according to executive Mhamed Ibnabdeljali.

And the reason we’re doing this is because this natural resource is there for us, but also for our future generations,” Ibnabdeljali says. “We have the responsibility to make sure that it is used and produced appropriately and responsibly.”

For years, the United States was one of the biggest phosphate producers. But now its reserves are dwindling. Meanwhile,l big reserves elsewhere are not only limited, they’re also located in countries where supply could be uncertain, places like China, Iraq and Syria

That’s important because in a world of scarce and unequally distributed resources, anything can happen. In a crisis, the haves might hoard and the have nots would just suffer. That’s just what happened in 2007 and 2008, when food prices shot up around the world, and prices of fertilizer and phosphorus followed. To protect its domestic supply, China increased its export tariff on phosphates, a move that effectively stopped exports for a time.

That’s about the same time that people like David Vaccari started to hear about the notion of peak phosphate—concerns that the world was heading into a crunch for a key ingredient in the global food chain.

But Mhamed Ibnabdeljali says the idea was news to Morocco.

“We were very surprised to hear about this peak phosphate,” Ibnabdeljali says. “Because certainly by the measures we had seen, there were hundreds of years worth of reserves.”

Morocco certainly isn’t worried about running out of phosphate. New studies have also revealed new phosphate resources elsewhere, all over the world. And after the 2008 supply squeeze, the price of phosphate settled at a new, much higher level. That alone has jumpstarted exploration, with mining companies going after supplies and using technology that had been too expensive to extract.

But the warnings continue.

Iza Kruszewska, a sustainable agriculture campaigner for Greenpeace, says there might be other limiting factors to actually producing more phosphate.

Kruszewska says talk about new phosphate mines and technology is missing the point. Water needed to process the rock could become scarce, she says, as it already is in some parts of Morocco. Or the rising cost of mining could price out some customers, leaving them without access to chemical fertilzer.

And Kruszewska says even an unlimited supply of phosphorus wouldn’t be a good thing, because we’ve already got too much of it where we don’t want it.

“We are living in a sea of nutrients” like phosphorus, Kruszewska says.

It turns out that a lot of the fertilizer applied around the world doesn’t actually help crops grow. Instead, it flows off of fields into nearby waterways, where its phosphorus and nitrogen can causes big environmental problems. So Kruszewska says the key isn’t just to dig up more.

Fortunately, phosphorus isn’t a single-use product like gasoline. It can be used over and over, as long as you capture it in some way.

“We should be better at capturing the phosphate that’s already in the system rather than just mining more and more of it, because that’s got to stop somewhere,” Kruszewska says.

David Vaccari of the Stevens Institute likes the idea of recycling.

“Reducing the losses in the cycle means improving agricultural efficiency,” Vaccari says. Efficiency is the amount of crop you get for each input. For fertilizer, you can increase efficiency by reducing soil erosion, increasing organic matter and applying it more carefully.

But Vaccari says there are tradeoffs, especially with an ever growing demand for food.

“That’s quite a challenge, and it means that you really need to optimize yields,” Vaccari says. “Population growth may be working against us.”

Which means that however you look at it, phosphorus is going to continue to be a flashpoint in the global food supply, with swirling concerns over how much there is, how it’s mined and processed, and how it’s used.

And it leaves Morocco sitting pretty, with literally mountains of a limited resource that the world just can’t seem to get enough of.