Commentary: Phosphorus phobia?
Geneviève Metson is a doctoral student at Montreal’s McGill University who is studying an interesting offshoot of agricultural sustainability: Phosphorus.
That’s right. Phosphorus. Not exactly top of mind when it comes to potential crises in food production.
However, as Metson’s research statement explains, “Phosphorus is a scarce resource essential to food production, but in too large quantities can also cause pollution in water bodies. More sustainable phosphorus management is essential for food security and pollution abatement.”
No argument here.
For the most part, phosphorus is considered a non-renewable resource, since its principal commercial source in modern times is apatite, phosphate-containing rock (in previous centuries, phosphorus was primarily obtained from animal bones or phosphorus-rich guano). Although significant deposits of apatite are found in Florida, Tennessee, Idaho and Utah, fully one-half of the world’s reserves of phosphorus are located in Arab nations.
That makes sustainable phosphorus management an important strategic priority and Metson’s research something more than an intriguing thesis topic.
But here’s the kicker: She’s focused on finding out how much of the phosphorus that’s mined for use as a nutritional additive in animal rations or for commercial fertilizer to grow feed crops ends up directed toward meat production.
That fits right in with the current fad of calculating the carbon footprint and the resource consumption required to produce a pound of beef, pork or chicken. Those charts provide a visual snapshot of the land area, water use and energy consumption—allegedly—needed to put a hamburger or a chicken breast on somebody’s dinner plate. (Here is an example of one such infograph, developed by Dr. Judith Capper, a dairy scientist who has done extensive research on sustainable livestock production: www.npr.org/blogs/thesalt/2012/06/27/155527365/visualizing-a-nation-of-meat-eaters)
It’s all about the footprint
Not surprisingly, Metson determined that meat production is one of the most prominent food sectors dependent on phosphorus. Thus, as she argued in a communication published in Environmental Research Letters, meat’s phosphorus footprint is reason enough to eat less of it, given that phosphorous is a finite resource.
“Changes we can make in our diet to decrease the demand for mined phosphorus can also decrease the use of other resources,” Metson told National Public Radio. “We need to manage our food system in an equitable and sustainable way.”
To be sure, extracting phosphates from deposits around the world has helped fuel a major increase in global food production. Phosphate production in 2012 was 220 million tons, up from 165 million tons in 1994.
But is phosphorus availability really a serious concern? Not according to the Alabama-based International Fertilizer Development Center, an organization dedicated to improving food security, agricultural productivity and economic development through farm efficiency.
I have a lot of respect for IFDC, an organization that gets involved with controversial issues but maintains its focus on initiatives that move the needle. For example: Its priorities include projects to reduce food waste, improve access to modern farming technologies and fertilizer, expand sustainable energy production and improve market access for farm products grown in developing countries.
As for phosphorus, Steven Van Kauwenbergh, the principal scientist and leader of IFDC’s Phosphate Research and Resources Initiative, stated that, “Phosphorus is pretty far down the list of things we’re going to suddenly run out of.”
A 2010 IFDC report titled, “World Phosphate Rock Reserves and Resources,” projected that even with current rates of production, phosphate rock reserves should last another 300 to 400 years.
Van Kauwenbergh also noted that IFDC’s approach to improving farm productivity, particularly in areas where improper management or monoculture cropping has depleted the soil, includes a combination of organic soil amendments and use of inorganic fertilizers to rebuild fertility. It’s not just about adding nitrogen (derived principally from natural gas) or phosphorus; soil fertility also depends on a proper balance of organic matter to promote water retention and root development.
Metson, however, argued that the growth of phosphate usage worldwide is unsustainable, noting in her letter that, “[The] global per capita phosphorus footprint has increased 38% over the last 50 years.”
In making the point that meat-eating corresponds with phosphorus use, she noted that Luxembourg—considered the world’s heaviest meat-eating country—consumes 16.8 pounds of phosphorus per person, while The Congo’s per capita use is less than one pound a year. (Interestingly, though, Canada—certainly a country that’s hardly adverse to meat eating—has seen its per capita use of phosphorus actually decrease since the 1960s.)
So while it’s difficult to make conclusive judgments about phosphorus and meat production, it seems safe to say that the world will face critical shortages of oil—a far greater concern for agriculture—much sooner than any imaginable phosphorus crisis.
Phosphorus is something to think about, but nothing to lose sleep over.
The opinions expressed in this commentary are solely those of Dan Murphy, a veteran food-industry journalist and commentator.