SRM 1957 Organic Contaminants in Non-Fortified Human Serum (Freeze-Dried) - This Standard Reference Material (SRM) is intended for use in evaluating analytical methods for the determination of selected polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and polybrominated diphenyl ether (PBDE) congeners in human serum and similar matrices. Reference values are provided for selected polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), perflourinated compounds (PFCs), and serum lipid.

SRM 1958 Organic Contaminants in Fortified Human Serum (Freeze-Dried) - This Standard Reference Material (SRM) is intended for use in evaluating analytical methods for the determination of selected polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and polybrominated diphenyl ether (PBDE) congeners in human serum and similar matrices. Reference values are provided for selected polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho PCB congeners, perfluorinated compounds (PFCs), and serum lipid.

Organics in Mussel Tissue (Mytilus edulis) - This Standard Reference Material (SRM) is a frozen mussel tissue homogenate intended for use in evaluating analytical methods for the determination of selected polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and polybrominated diphenyl ether (PBDE) congeners in marine bivalve mollusk tissue and similar matrices. All of the constituents for which certified and reference values are provided in SRM 1974c were naturally present in the tissue material before processing.

Standard Reference Material 200b Potassium Dihydrogen Phosphate (KH2PO4) - This Standard Reference Material (SRM) is a highly purified and homogeneous lot of crystalline potassium dihydrogen phosphate (KH2PO4). It is intended primarily for use as a working standard in the calibration and standardization of procedures employed in the fertilizer industry for the determination of potassium and phosphorus. A unit of SRM 200b consists of one bottle containing 90 g of crystalline potassium dihydrogen phosphate. This data is public in the Certificate of Analysis for this material.

SRM 2193a Calcium Carbonate pH Standard [used as saturated Ca(OH)2 solution] - This Standard Reference Material (SRM) is intended for use in preparing solutions for calibrating electrodes for pH measuring systems at pH values above 11.0. This lot of calcium carbonate (CaCO3) was selected for its low level of alkali metal impurities. However, this SRM is certified ONLY as a pH standard, NOT as a pure substance. A unit of SRM 2193a consists of 30 g of CaCO3. This data is public in the Certificate of Analysis for this material.

Donor serum for SRM 2378 was collected from three groups of individuals: (level 1) three healthy donors who took 1000 mg/day of fish oil supplements for a minimum of one month prior to collection; (level 2) three healthy donors who took 1000 mg/day of flaxseed oil supplements for a minimum of one month prior to collection; and (level 3) three healthy donors who did not take either fish or flaxseed oil supplements for one month prior to collection.

SRM 2585 Organic Contaminants in House Dust - This Standard Reference Material (SRM) is intended for use in evaluating analytical methods for the determination of selected polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and polybrominated diphenyl ether (PBDE) congeners in house dust and similar matrices. All of the constituents for which certified, reference, and information values are provided in SRM 2585 were naturally present in the dust material before processing.

This Standard Reference Material (SRM) is a primary gas mixture for which the amount-of-substance fraction, expressed as concentration, may be related to secondary working standards. This SRM is intended for the calibration of instruments used for nitric oxide determinations and for other applications. This data is public in the Certificate of Analysis for this material.

SRM 2950a Respirable Alpha Quartz on Filter Media (Nominal Mass of Alpha Quartz: 5 µg to 500 µg) - This Standard Reference Material (SRM) is intended primarily for the calibration of X-ray diffraction (XRD) spectrometers for the determination of respirable alpha quartz using National Institute for Occupational Safety and Health (NIOSH) Method 7500, or the equivalent. This data is public in the Certificate of Analysis for this material.

SRM 2973 Vitamin D Metabolites in Frozen Human Serum (High Level) - This Standard Reference Material (SRM) is intended for use as an accuracy control in the critical evaluation of methods for determining the amount-of-substance concentration of vitamin D metabolites in human serum. This SRM can also be used as a quality assurance tool for assigning values to in-house control materials for these constituents. This data is public in the Certificate of Analysis for this material.