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Phosphorus: Essential to Life—Are We Running Out?

applying phosphorus fertilizer
Fertilizing a corn field in Iowa. Photo credit: U.S. Department of Agriculture

Phosphorus, the 11th most common element on earth, is fundamental to all living things. It is essential for the creation of DNA, cell membranes, and for bone and teeth formation in humans. It is vital for food production since it is one of three nutrients (nitrogen, potassium and phosphorus) used in commercial fertilizer. Phosphorus cannot be manufactured or destroyed, and there is no substitute or synthetic version of it available. There has been an ongoing debate about whether or not we are running out of phosphorus. Are we approaching peak phosphorus? In other words, are we using it up faster than we can economically extract it?

In fact, there is plenty of phosphorus left on Earth. Animals and humans excrete almost 100 percent of the phosphorus they consume in food. In the past, as part of a natural cycle, the phosphorus in manure and waste was returned to the soil to aid in crop production. Today phosphorus is an essential component of commercial fertilizer. Because industrial agriculture moves food around the world for processing and consumption, disrupting the natural cycle that returned phosphorus to the soil via the decomposition of plants, in many areas fertilizer must now be continually applied to enrich the soil’s nutrients.

Most of the phosphorus used in fertilizer comes from phosphate rock, a finite resource formed over millions of years in the earth’s crust. Ninety percent of the world’s mined phosphate rock is used in agriculture and food production, mostly as fertilizer, less as animal feed and food additives. When experts debate peak phosphorus, what they are usually debating is how long the phosphate rock reserves, i.e. the resources that can economically be extracted, will hold out.

Pedro Sanchez, director of the Agriculture and Food Security Center at the Earth Institute, does not believe there is a phosphorus shortage. “In my long 50-year career, “ he said,  “once every decade, people say we are going to run out of phosphorus. Each time this is disproven. All the most reliable estimates show that we have enough phosphate rock resources to last between 300 and 400 more years.”

In  2010, the International Fertilizer Development Center determined that phosphate rock reserves would last for several centuries. In 2011, the U.S. Geological Survey revised its estimates of phosphate rock reserves from the previous 17.63 billion tons to 71.65 billion tons in accordance with IFDC’s estimates. And, according to Sanchez, new research shows that the amount of phosphorus coming to the surface by tectonic uplift is in the same range as the amounts of phosphate rock we are extracting now.

Global meat consumption from 1961 to 2009. Photo credit: FAO
Global meat consumption from 1961 to 2009. Photo credit: FAO

The duration of phosphate rock reserves will also be impacted by the decreasing quality of the reserves, the growing global population, increased meat and dairy consumption (which require more fertilized grain for feed), wastage along the food chain, new technologies, deposit discoveries and improvements in agricultural efficiency and the recycling of phosphorus. Moreover, climate change will affect the demand for phosphorus because agriculture will bear the brunt of changing weather patterns. Most experts agree, however, that the quality and accessibility of currently available phosphate rock reserves are declining, and the costs to mine, refine, store and transport them are rising.

Ninety percent of the phosphate rock reserves are located in just five countries: Morocco, China, South Africa, Jordan and the United States. The U.S., which has 25 years of phosphate rock reserves left, imports a substantial amount of phosphate rock from Morocco, which controls up to 85 percent of the remaining phosphate rock reserves. However, many of Morocco’s mines are located in Western Sahara, which Morocco has occupied against international law. Despite the prevalence of phosphorus on earth, only a small percentage of it can be mined because of physical, economic, energy or legal constraints.

In 2008, phosphate rock prices spiked 800 percent because of higher oil prices, increased demand for fertilizer (due to more meat consumption) and biofuels, and a short-term lack of availability of phosphate rock. This led to surging food prices, which hit developing countries particularly hard.

With a world population that is projected to reach 9 billion by 2050 and require 70 percent more food than we produce today, and a growing global middle class that is consuming more meat and dairy, phosphorus is crucial to global food security. Yet, there are no international organizations or regulations that manage global phosphorus resources. Since global demand for phosphorus rises about 3 percent each year (and may increase as the global middle class grows and consumes more meat), our ability to feed humanity will depend upon how we manage our phosphorus resources.

Unfortunately, most phosphorus is wasted. Only 20 percent of the phosphorus in phosphate rock reaches the food consumed globally. Thirty to 40 percent is lost during mining and processing; 50 percent is wasted in the food chain between farm and fork; and only half of all manure is recycled back into farmland around the world.

Eutrophication in the Caspian Sea. Photo credit: Jeff Schmaltz, NASA
Eutrophication in the Caspian Sea. Photo credit: Jeff Schmaltz, NASA

Most of the wasted phosphorus enters our rivers, lakes and oceans from agricultural or manure runoff or from phosphates in detergent and soda dumped down drains, resulting in eutrophication. This is a serious form of water pollution wherein algae bloom, then die, consuming oxygen and creating a “dead zone” where nothing can live. Over 400 coastal dead zones at the mouths of rivers exist and are expanding at the rate of 10 percent per decade. In the United States alone, economic damage from eutrophication is estimated to be $2.2 billion a year.

As the quality of phosphate rock reserves declines, more energy is necessary to mine and process it. The processing of lower grade phosphate rock also produces more heavy metals such as cadmium and uranium, which are toxic to soil and humans; more energy must be expended to remove them as well.  Moreover, increasingly expensive fossil fuels are needed to transport approximately 30 million tons of phosphate rock and fertilizers around the world annually.

Sanchez says that while there is no reason to fear a phosphorus shortage, we do need to be more efficient about our use of phosphorus, especially to minimize eutrophication. The keys to making our phosphorus resources more sustainable are to reduce demand and find alternate sources. We need to:

  • Improve the efficiency of mining
  • Integrate livestock and crop production; in other words, use the manure as fertilizer
  • Make fertilizer application more targeted
  • Prevent soil erosion and agricultural runoff by promoting no-till farming, terracing, contour tilling and the use of windbreaks
  • Eat a plant based diet
  • Reduce food waste from farm to fork
  • Recover phosphorus from human waste
Cow dung to be used as fertilizer drying in Punjab. Photo credit: Gopal Aggarwal http://gopal1035.blogspot.com
Cow dung to be used as fertilizer drying in Punjab. Photo credit: Gopal Aggarwal http://gopal1035.blogspot.com

Phosphorus can be reused. According to some studies, there are enough nutrients in one person’s urine to grow 50 to 100 percent of the food needed by another person. NuReSys is a Belgian company whose technology can recover 85 percent of the phosphorus present in wastewater, and turn it into struvite crystals that can be used as a slow fertilizer.

New phosphorus-efficient crops are also being developed. Scientists at the International Rice Research Institute discovered a gene that makes it possible for rice plants to grow bigger roots that absorb more phosphorus. The overexpression of this gene can increase the yield of rice plants when they are grown in phosphorus-poor soil. Rice plants with this gene are not genetically modified, but are being bred with modern techniques; they are expected to be available to farmers in a few years.

A breed of genetically modified Yorkshire pigs, called the Enviropig, has been developed by the University of Guelph in Canada to digest phosphorus from plants more efficiently and excrete less of it. This results in lower costs to feed the pigs and less phosphorus pollution, since pig manure is a major contributor to eutrophication. Last spring, however, the Enviropigs were euthanized after the scientists lost their funding.

The Agriculture and Food Security Center is working on food security in Africa and attempting to eliminate hunger there and throughout the tropics within the next two to three decades.

In the mountains of Tanzania along Lake Manyara, Sanchez’ team has discovered deposits of “minjingu,”  high-quality phosphate rock that is cheaper and just as efficient as triple super phosphate (a highly concentrated phosphate-based fertilizer) in terms of yields of corn per hectare.

Minjingu Mines & Fertilisers Ltd.. Photo credit: IFDC Photography
Minjingu Mines & Fertilisers Ltd.. Photo credit: IFDC Photography

Minjingu deposits are formed by the excreta and dead bodies of cormorants and other birds that roost and die in the mountains, forming biogenic rock phosphate or guano deposits. Guano, the feces and urine of seabirds (and bats), has a high phosphorus content, and in the past was often used as fertilizer.

Sanchez’ researchers have also discovered a common bush called the Mexican Sunflower that is an efficient phosphorus collector. It grows by the side of the road, fertilized by the excreta dumped there by farmers. The farmers cut it down and use it as green manure, an organic phosphorus fertilizer which helps grow high-quality crops like vegetables.

Mexican Sunflower. Photo credit: John Tann
Mexican Sunflower. Photo credit: John Tann

The Agriculture and Food Security Center team also helps farmers contain erosion and runoff by encouraging them to keep some vegetative cover, either alive or dead, on the soil year-round. This is done through intercropping, leaving crop residue in the fields, contour planting on slopes or terracing.

“There is no data to support the idea of peak phosphorus,” said Sanchez. “Just fears. New deposits are continually being discovered. We also have more efficient extraction that is getting more phosphate rock out of land-based sediments. And there is an enormous 49-gigaton deposit of phosphorus in the continental shelf from Florida to Maritime Canada that scientists have known about for years. Now there is some experimental extraction going on off the coast of North Carolina.”

Pedro Sanchez, author of Properties and Management of Soils in the Tropics published in 1976, which continues to be a bestseller, is currently working on Tropical Soils Science, an update of his previous work. It will be published by 2015.

Correction: This post was updated on March 22, 2019 to remove a statement that phosphorus is a renewable resource.

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James
8 years ago

Phosphorus is one of the vital nutrient that is needed for life to continue. Plants and Animals require phosphorus for their survival. It is essential for the creation of DNA, cell membranes, and for bone and teeth formation in humans. It is vital for food production since it is one of three nutrients (nitrogen, potassium and phosphorus) used in commercial fertilizer. Phosphorus cannot be manufactured or destroyed, and there is no substitute or synthetic version of it available.Thanks for sharing with us.

wachiuri
8 years ago

thank you for revealing those facts. esp that of a persons excreation and urine could produce up to 100% phosphorous enough to grow another persons food, it is a shame that in some excreta is buried underground

Claude Lord
8 years ago

Thanks for the great article. Although it is quite factual, I am disturbed by the fact that Pedro insists that we are not going to run out while saying that there is a 300 to 400 year supply.

My family has been farming the same property in Quebec for 374 years, since 1642.

To me, 3-400 years is not a long time at all. Unspoken is that Canada only has 2 mines and one has 30 years of reserve, the other 15. Time to move to sustainable agriculture now or you’ll be bending the knee to Morocco
Claude Lord

MARGARET WANGARI NGATIA
MARGARET WANGARI NGATIA
7 years ago

Thanks so much for that educative part.I will start a research to find out if processing of a lower grade phosphate rock could have been the cause of maize diseases we have being experiencing here in Kenya for the past 2 years.The disease is called Maize lethralnicrosis.Thanks once more.

dani dato
7 years ago

in morocco only 2% in western sahaha and the rest is in the north around Casablanca ….morocco is 75%ofthe world

Meryeme
Meryeme
Reply to  dani dato
1 year ago

there is no western Sahara, SAHARA is moroccan

Mogga Moses Ezibon
Mogga Moses Ezibon
6 years ago

Thanks for sharing this educative details about phosphorus, what I think might cause a lot fear in future is the different government polices restricting the export of phosphate fertilizer around the world.
Tanzania discovered the phosphate reserves since 1982 more than 30 years ago but their phosphate hasn’t reached many countries.
The government simply use it locally in supporting farmers through input subsidy programme and restricting export and banning imports through the Tanzania Bureau of Standard, so this restrictions can result in higher prices for phosphate fertilizers and eventually higher food crises in other parts of the world.

Stephanie
Stephanie
6 years ago

There are significant grasslands on Earth that are simply not used for cattle or chicken grazing. There is absolutely no need to grow grain for either, and neither animal should eat grains, especially corn. The agriculture industry is so expensive and inefficient that using grasslands to raise cattle and chickens would reduce their cost per unit by a factor of ten! That is just how badly corporations have managed agricultural affordability.

Scott
Scott
Reply to  Stephanie
4 years ago

Ok, just so you know. Your statement is factually incorrect. Chickens do not digest fiber. They eat cereal grains and are basically the most efficient resource converting animals in agriculture. It’s great to have these conversations, but let’s use facts and truth first, then discuss your political views.

Harun Gitari
Harun Gitari
6 years ago

It is time we rise up and create awareness on phosphorus existence in our ecosystems and how we can exploit it.

TF
TF
5 years ago

The Ahmish used to call it “night soil”.

Likely still do.

Jack
Jack
5 years ago

Phosphorus is not a renewable resource.

Ishaq ahmadi
5 years ago

Phosphorus is one of the vital nutrient that is needed for life to continue. Plants and Animals require phosphorus for their survival. It is essential for the creation of DNA, cell membranes, and for bone and teeth formation in humans. It is vital for food production since it is one of three nutrients (nitrogen, potassium and phosphorus) used in commercial fertilizer. Phosphorus cannot be manufactured or destroyed, and there is no substitute or synthetic version of it available.Thanks for sharing with us.

Elizabeth
Elizabeth
3 years ago

how much of phosphorus do we use yearly?

Dr Sterling Colgate
Dr Sterling Colgate
3 years ago

Where can you find a fluids separation plant that would extract the minerals. I’m guessing Zinc would also be a valuable extract, since much of the bio-available dietary zinc (necessary for proper immune function) is not transported into the cell without a suitable Ionophore (like quercetin found in red berries such as elderberry), and simply excreted.

Wonder how difficult it would be to build a fluids seperation facility. Seems like everyone is filled with piss and vinegar…may as well get rich with it and save the planet as well?

Dennis Njirika
Dennis Njirika
3 years ago

Great work. I enjoyed reading. Province is indeed good. Peak phosphorus might as well be a fantasy. Yet, man should encourage use of guano and other organic manure in agricultural production. Our ancestor used them, successfully. Understandably, the rapid increase in global population and consequently increased food demand makes the enhanced use of phosphorus more urgent, in the short run.

Niks
Niks
3 years ago

It’s so sad that even natural resources are soon can be gone. Phosphorus is important . But what to do when it’s gone

kgrfbfsx
kgrfbfsx
Reply to  Niks
1 year ago

i dont suppose that an element will like just “disappear” from the earth. Phosphorus as an element will still be pretty much abundant, just much less accessible. I mean, its not like we are throwing out all the phosphorus we use out into space, but the concern here is that its inefficient and unsustainable. The phosphorus will still be here, but believe me, extracting phosphorus from piss is probably much much more easier than extracting phosphorus from landfills, corpses, decomposites and several km underground.

IFEOMA JOY
IFEOMA JOY
3 years ago

Thanks for sharing educative details on Phosphorus with us. I think is high time we create awareness on phosphorus, how important it is to the ecosystem and how we can alternatively exploit it. The very aspect where you made mention of excretion and urine producing 100% of phosphorus large enough to produce another person’s food really caught my attention, thank you once again for taking us through this educative section.

Mercy jepkoech
Mercy jepkoech
3 years ago

Humans activities can cause climate change

Mjomba
Mjomba
3 years ago

It seems Sanchez’s team were the first humans to set foot in the village of Minjingu in Tanzania. Didn’t they also discover an Agriculture Training College and factory for producing fertilizer also in the same village?

Ahmad Mahdavi
1 year ago

Considering the very bad enforcement of laws and regulations in particular in agricultural sector in most developing countries we should be very worry about what is happening to our soils in developing countries, lots of HCH, POPs, Highly Hazardous Pesticides, Forever chemicals pressure on our soils then what will be left behind for our next generations, we need more actions from related Un agencies particularly from FAO. Last month in Feb. 2023 I talked in Zaragoza for the 14th International HCH and pesticide forum about Highly Hazardous Pesticides (HHP), these groups of pesticides stil in use in many developing countries are destroying whole soil biodiversity. Although we already learned a lot from EPA and later in these recent years from ECHA, etc., but wondering to see that the most important World Environmental Agency allows exporting HHP from developed world to developing countries. Here in developing countries we are facing and suffering from HHP, every year many killed by HHP here. According to our last communications under SAICM there are strong evidences that EU also is exporting (perhaps the main exporter) HHP to developing countries.  

Last edited 1 year ago by Ahmad Mahdavi
Jacob
Jacob
4 months ago

Just a thought. I’m quoting a line I heard recently, “Phosphorus cannot be created and cannot be destroyed”. Your question answers itself.

This would mean that phosphorus will never run out and is in fact a renewable resource. The caveat to that is because we have not yet researched exactly how to renew phosphorous cheaply the cost of renewing phosphorus will will climb exponentially.

There is a supply and demand curve going on. When the cheap supply of phosphorus rock becomes too expensive to use then the entire globe will snap into gear to find a phosphorus renewal technology that is so cheap we won’t need to use the rocks any more.

(Think Spence diamonds, the diamond companies started to make a better quality diamond in a factory when the cost of ethical diamonds in a mine became economically uncertain)