Selenium: Properties and Determination

Selenium is an essential trace element having a very narrow range between deficient, essential, and toxic doses. The wide geographic variation in soil selenium concentration, reflected in its content in food, has significant impacts on the dietary supply of this element to humans. An extensive effort has been done in recent years to develop analytic techniques and methods able to perform accurate determination of selenium and its species in environmental and biological matrices. They are powerful tools to elucidate the biogeochemical processes, metabolic pathways, and health effects in which selenium is involved.