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HISTORY AND EPIDEMIOLOGY
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Phosphorus is a nonmetallic essential element discovered hundreds of years ago that exists in 3 forms, with white phosphorus being the most important from a toxicological standpoint. The word “phosphorus” means light-bearer, which originates from its property of glowing when exposed to air. Its luminescent and pyrotechnic qualities resulted in widespread use in matches and fireworks, and its toxic properties was historically used as a rodenticide. It is still encountered occasionally and remains in use for munitions and in chemical syntheses. Biologically, it is present in living organisms as the phosphate ion that is an entirely different entity than the elemental phosphorus and not considered in this chapter.
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Phosphorus is a nonmetallic element not naturally found in its elemental form; the white allotropic form was isolated from urine by Hennig Brandt in 1669. White phosphorus has been used in munitions since World War I for its antipersonnel effect as well as its warning, incendiary, and smoke producing properties. It is also used in fireworks in countries other than the United States (where consumer-grade fireworks containing white phosphorus are illegal) and for some chemical synthetic processes. White phosphorus was used extensively in the past as a rodenticide but is no longer permitted for this purpose in the United States. Because of the potential use of phosphorus for illicit drug manufacturing of methamphetamines, its sale is monitored by the US Drug Enforcement Administration. Before modern regulation, it was used in scientifically unsubstantiated remedies primarily because its phosphorescent and reactive qualities suggested potency. Its occasional use for homicides was limited by its characteristic luminescent, smoking qualities; however, it remains a method of suicide in some countries.
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At the beginning of the 20th century, phosphorus was used in millions of “strike anywhere” matches (lucifers). However, safety concerns with the matches and illnesses in the workers producing the matches prompted a shift from using the more dangerous white phosphorus in the match heads to substituting the safer red phosphorus in the strikers. Workers chronically exposed to white phosphorus developed “phossy jaw,” an illness characterized by disfiguring osteonecrosis of the mandible along with multiple draining abscesses and bony loss. Although the disease was actually of low prevalence among phosphorus workers, the painful, visible deformities in otherwise healthy young people drew widespread attention.
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CHEMISTRY AND PHARMACOLOGY
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Phosphorus, atomic number 15, is in group 15 (CAS group VA) which is made up of nonmetals, metalloids, and metal elements; shares chemical properties with nitrogen (above) and arsenic (below) in the periodic table. Elemental phosphorus exists in several different allotropes (polymorphs); the 2 common forms considered in this chapter are red phosphorus and the highly reactive white phosphorus. The black allotrope is reasonably stable at standard conditions and has potential novel application in electronics because of its semiconductive planar crystalline structure and multiple anisotropic physical properties. ...