An Insight into the Paradox of Selenium

Authors: Ziad Moussa*

DOI: 10.23880/macij-16000140

Volume 3, Issue 2

Abstract

Did you know that out of the 90 elements that exist in nature, 25 constitute the human body? The largest of those elements is iodine, followed by molybdenum. Selenium ranks third. There has been a historical misconception surrounding the toxicity of selenium and it has been long overdue to set the record straight. The formal discovery of selenium dates back to the year 1818 and is attributed to the Swedish chemist J. J. Berzelius. Shortly thereafter, the synthesis of numerous organoselenium derivatives, including selenides, alkyl selenols, selenoxides, and diselenides, was described by several research groups. Many such compounds were unpleasant to handle due their unstable or highly malodorous nature. These properties discouraged intensive research in the area of organoselenium chemistry and hampered the development of the field, leading to relatively slow progress for many decades. In 1927 elemental selenium was discovered to mediate the dehydrogenation of cyclic and polycyclic hydrocarbons to aromatic compounds, and shortly afterwards selenium dioxide were patented for its synthetic utility as an oxidant. These discoveries, along with the subsequent recognition that selenium is an essential trace nutrient for animals, prompted more intensive scrutiny of many aspects of the element and its derivatives, including their biological, physical, analytical, and chemical properties. A review describing the early organic chemistry of selenium appeared in 1963 and the first comprehensive book on the subject, edited by Klayman and Gunther, was published in 1973.

Keywords: Toxicity of Selenium; Organoselenium Derivatives; Biological; Physical

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