Selenium is a metal-like element signified by the atomic symbol Se. The average atomic weight of its isotopes is 78.96, and its atomic number is 34. The element exists in at least three allotropic forms, which may be either amorphous or crystalline and...

Selenium is the third element in Group 16 of the periodic family. The members of this family are sometimes referred to as the chalcogens, meaning "ore-forming." Selenium has an atomic number of 34, an atomic mass of 78.96, and a chemical symbol of Se....

A member of Group VIA of the periodic table, this metal occurs widely but unevenly in the earth’s crust. Its concentration is about 4 micrograms per liter in seawater. It is toxic in elevated concentrations to humans and aquatic life. The maximum...

Nonmetallic element sensitive to light; used as a coating on drums of photocopying...

Selenium (pronounced /səˈliːniəm/) is a chemical element with atomic number 34, with the chemical symbol Se. It is a nonmetal, chemically related to sulfur and tellurium, and rarely occurring in its elemental state in nature. It is toxic in large...

AMERICANS RARELY HAVE DEFICIENCIES OF THIS TRACE MINERAL, BUT IT NEVER HURTS TO BE INFORMED Selenium may not be the most recognizable mineral in the supplement aisle (as opposed to, say, calcium, magnesium or iron), but it does play an important role in...

Introduction [ILLUSTRATION OMITTED] Until the late 1950s, selenium was believed to be a toxic element. In 1957, Schwarz and Foltz established selenium as an essential trace element in the diet for the prevention of disease. (1) In food, selenium is derived...

South Dakota State University researchers are looking for ways to increase the amount of the trace mineral selenium in flour.Flour that is high in selenium could create a market for farmers along the Missouri River, where the selenium content is high, said Padmanaban Krishnan, a...

Federal regulators have ordered Atlantic Richfield Co. to take the first major step toward cleaning up contamination at an abandoned copper mine in northern Nevada, saying it poses an "imminent and substantial threat."The U.S. Environmental Protection Agency ordered the company to begin determining the extent...