Celebrating the 350th Anniversary of Phosphorus Discovery: A Conundrum of Deficiency and Excess

Abstract

2019 will be the 350th anniversary of the discovery of phosphorus (P) by the alchemist Hennig Brandt. This perspective traces the historical threads that P has weaved through the fabric of our society and identifies challenges to improve P stewardship in the future and for our future. A century after Brandt's discovery, P was identified in bone ash, which became the primary source of P until guano and ultimately rock P was mined to provide the various mineral formulations used today. Owing to limited supplies, a strategic shift in resource management ethics-from exploiting to conserving P resources-is needed. In agriculture, remedial strategies should consider when conservation practices can transition from P sinks to sources; however, a broader, long-term strategy for P stewardship is needed. This must include Reducing P loss in food and other wastes, Recovering P from waste streams, Reusing P generated beneficial by-products, and Restructuring production systems. A key action to enact such changes will be collaboration across all sectors of society and the supply chain, from field to fork and beyond. As this will likely increase the cost of food, fiber, and feed production, it will require an innovative mix of public and private initiatives. A Glowing Start P hosphorus (P) was discovered by the alchemist Hennig Brandt in 1669, when he accidentally extracted it from a copious store of human urine (22 hog heads or 5500 L of urine) while searching for the illusive "philosopher's stone, " believed to transform base metals into gold (Powers, 2017). Thus, P became the first element discovered with modern scientific techniques, partly because it is so reactive in elemental form that it never occurs free in nature. By the glow of this new substance, soon to be named "cold fire, " Brandt had found the P in pee! Ironically, we are still trying to find efficient and cost-effective methods to extract P from human and animal excreta. Which goes to show how little some things have changed over the last three and a half centuries. Phosphorus is the sixth most abundant element in living organisms. It is an essential constituent of all life, from DNA and our genetic code, to the phospholipids of cell membranes, to the apatite of our bones, to ATP, the basic currency of all metabolic processes. Fertilizer P has provided the foundation for commercial food, fiber, and bioenergy production, supporting population growth and facilitating the transition to modern urbanized societies. However, events in the last 50 to 60 years have highlighted a conundrum of P deficiencies and excesses. During this time, publicized concerns about depletion of rock phosphate (the nonrenewable raw material for most P fertilizers) have arisen concurrently with growing concern about P use inefficiencies (e.g., losses from agriculture and wastewater) and the harm excess P can bring to the ecological balance of streams, rivers, lakes, estuaries, and seas worldwide. Indeed, eutrophication of surface waters has resulted in proliferation of cyanobacteria, early life forms that have existed for more than 3.5 billion years, 10 million times older than our knowledge of P. These early life forms, which generated the oxygen atmosphere on which we depend, and which shaped the course of evolution and ecological change, are now responding to our increasingly inefficient use of P, triggering environmental degradation and harm. These environmental concerns, along with our longstanding efforts to extract P from waste, provide just Abbreviations: PAHs, polycyclic aromatic hydrocarbons; DOM, dissolved organic matter; DOC, dissolved organic carbon; SOM, solid organic matter.