selenium

(sĕ-lē′nē-ŭm)

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[Gr. selēnē, moon + -ium (1) (so named because it resembles tellurium)]
SYMB: Se A chemical element resembling sulfur; atomic weight (mass) 78.96, atomic number 34. It is considered an essential trace element in the diet. Toxicity can occur when an excessive amount is ingested, characterized by a sour breath odor, nausea, vomiting, abdominal pain, restlessness, hypersalivation, and muscle spasms.
CAS # 7782-49-2

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