Isotopes
Naturally selenium contains six stable isotopes. Fifteen other isotopes have been characterized. The
element is a member of the sulfur family and resembles sulfur both in its various forms and in its
compounds.
Uses
Selenium is used in Xerography for reproducing and copying documents, letters, etc. It is used by the
glass industry to decolorize glass and to make ruby-colored glasses and enamels. It is also used as a
photographic toner, and as an additive to stainless steel.
Handling
Hydrogen selenide in a concentration of 1.5 ppm is intolerable to man. Selenium occurs in some solid in
amounts sufficient to produce serious effects on animals feeding on plants, such as locoweed, grown in
such soils. Exposure to selenium compounds (as Se) in air should not exceed 0.2 mg/m 3 (8-hour
time-weighted average - 40-hour week).
Cost
Selenium is priced at about $300/lb. It is also available in high-purity form at a somewhat higher cost.
Sources: CRC Handbook of Chemistry and Physics and the American Chemical Society.
Last Updated: 12/19/97, CST Information Services Team
Selenium