title: Standard Reference Materials for dioxins and other environmental pollutants.
abstract: The National Institute of Standards and Technology issues approximately 1100 Standard Reference Materials (SRMs) certified for chemical composition or physical properties. A number of these SRMs has been developed to assist chemists in analyzing environmental samples more reliably for chlorinated dioxins and other organic pollutants. Certification of the pollutant concentration in a natural matrix SRM is based on concordant analyses by the NIST Organic Analytical Research Division using at least two independent methods. For a calibration solution, such as SRM 1614, Dioxin (2,3,7,8-TCDD) in Isooctane, certification is based on agreement of the calculated concentration based on the gravimetric preparation and the concentration as determined experimentally. SRM 1614 also includes a 13C-labeled 2,3,7,8-TCDD for use as an internal standard in methods based on gas chromatography/mass spectrometry. The certified concentrations (ng g-1) are 98.3 +/- 3.3 for the unlabeled dioxin and 95.6 +/- 1.5 for the labeled dioxin. The certificates for SRM 1588, Organics in Cod Liver Oil, and SRM 1589, Polychlorinated Biphenyls (as Aroclor 1260) in Human Serum, provide noncertified concentrations of dioxins. Concentrations of chlorinated dioxins in two urban particulate SRMs have been reported in the literature.
authors.affiliation: Standard Reference Materials Program, National Institute of Standards & Technology, Gaithersburg, MD 20899.
authors.forename: R
authors.initials: R
authors.lastname: Alvarez
mesh_terms: D004147:Dioxins / Q000032:analysis / Q000592:standards*; D004785:Environmental Pollutants / Q000032:analysis*; D006077:Government Agencies; D000072317:Polychlorinated Dibenzodioxins / Q000032:analysis / Q000592:standards*; D012015:Reference Standards; D014481:United States
chemical_list: D004147:Dioxins; D004785:Environmental Pollutants; D000072317:Polychlorinated Dibenzodioxins