title: Evaluation of selenium in dietary supplements using elemental speciation.
abstract: Selenium-enriched dietary supplements containing various selenium compounds are readily available to consumers. To ensure proper selenium intake and consumer confidence, these dietary supplements must be safe and have accurate label claims. Varying properties among selenium species requires information beyond total selenium concentration to fully evaluate health risk/benefits A LC-ICP-MS method was developed and multiple extraction methods were implemented for targeted analysis of common "seleno-amino acids" and related oxidation products, selenate, selenite, and other species relatable to the quality and/or accuracy of the labeled selenium ingredients. Ultimately, a heated water extraction was applied to recover selenium species from non-selenized yeast supplements in capsule, tablet, and liquid forms. For selenized yeast supplements, inorganic selenium was monitored as a means of assessing selenium yeast quality. A variety of commercially available selenium supplements were evaluated and discrepancies between labeled ingredients and detected species were noted.
authors.affiliation: US FDA Forensic Chemistry Center, Cincinnati, OH 45237, USA. Electronic address: kevin.kubachka@fda.hhs.gov.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Kubachka
authors.affiliation: US FDA Forensic Chemistry Center, Cincinnati, OH 45237, USA. Electronic address: traci.hanley@fda.hhs.gov.
authors.forename: Traci
authors.initials: T
authors.lastname: Hanley
authors.affiliation: US FDA Forensic Chemistry Center, Cincinnati, OH 45237, USA. Electronic address: madhavi.mantha@fda.hhs.gov.
authors.forename: Madhavi
authors.initials: M
authors.lastname: Mantha
authors.affiliation: US FDA Forensic Chemistry Center, Cincinnati, OH 45237, USA. Electronic address: robert.wilson@fda.hhs.gov.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wilson
authors.affiliation: US FDA Forensic Chemistry Center, Cincinnati, OH 45237, USA. Electronic address: travis.falconer@fda.hhs.gov.
authors.forename: Travis M
authors.initials: TM
authors.lastname: Falconer
authors.affiliation: Minnesota Department of Agriculture, Saint Paul, MN 55155, USA. Electronic address: zena.kassa@state.mn.us.
authors.forename: Zena
authors.initials: Z
authors.lastname: Kassa
authors.affiliation: University of Cincinnati, Department of Chemistry, Cincinnati, OH, USA. Electronic address: alinefo@gmail.com.
authors.forename: Aline
authors.initials: A
authors.lastname: Oliveira
authors.affiliation: University of Cincinnati, Department of Chemistry, Cincinnati, OH, USA. Electronic address: julio_landero80@yahoo.com.
authors.forename: Julio
authors.initials: J
authors.lastname: Landero
authors.affiliation: University of Cincinnati, Department of Chemistry, Cincinnati, OH, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Caruso
mesh_terms: D019587:Dietary Supplements / Q000032:analysis* / Q000592:standards; D004305:Dose-Response Relationship, Drug; D064586:Selenic Acid / Q000032:analysis; D012643:Selenium / Q000032:analysis*; D018036:Selenium Compounds / Q000032:analysis; D017279:Selenocysteine / Q000031:analogs & derivatives / Q000032:analysis; D012645:Selenomethionine / Q000032:analysis
chemical_list: D018036:Selenium Compounds; D017279:Selenocysteine; D012645:Selenomethionine; D012643:Selenium; D064586:Selenic Acid; C002979:selenomethylselenocysteine
keywords: Dietary supplement; LC-ICP-MS; Selenium; Speciation