U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by:

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 1 - 25 of 61

Comparison of primary laser spectroscopy and mass spectrometry methods for measuring mass concentration of gaseous elemental mercury

December 10, 2020
Author(s)
Abneesh Srivastava, Stephen E. Long, James E. Norris, Colleen E. Bryan Sallee, Jennifer Carney, Joseph Hodges
We present a direct comparison between two independent methods for the measurement of gaseous elemental mercury (GEM) mass concentration: isotope dilution cold-vapor inductively coupled plasma mass spectrometry (ID-CV-ICP-MS) and laser absorption

Development of a pregnancy-specific reference material for thyroid biomarkers, vitamin D, and nutritional trace elements in serum

October 24, 2020
Author(s)
Ashley Russell, Lisa Kilpatrick, Carolyn Burdette, Denise S. Tevis, Zachary A. Fultz, Michael Nelson, Jeff M. Jarrett, Stephen A. Wise, Brittany Kassim, Stephen E. Long
Background Concentrations of critical metabolites, hormones, and nutritional elements change significantly throughout pregnancy. Therefore, increased matrix complexity is a challenge for the measurement of these biomarkers. To provide a quality assurance

Certification of Standard Reference Material(R) 955d, Toxic Elements and Metabolites in Frozen Human Blood

October 15, 2020
Author(s)
Lee L. Yu, Karen E. Murphy, Colleen E. Bryan Sallee, Thomas W. Vetter, Robert C. Hagwood, George C. Caceres, Stephen E. Long, J M. Jarrett, M A. Franklin, J Castro Georgi, D M. Jones, Robert Jones, Z Li, Y L. Sommer, D S. Tevis, K Wallon, C D. Ward, M Maras, S Erdahl, C Gilmer, M Wermers, H Woldeysus, K F. Mehigan, M Morrissette, Christopher D. Palmer, Patrick J. Parsons
Standard Reference Material (SRM) 955d is intended for use in validating analytical methods for measuring toxic elements and mercury species in human blood, and in value assigning locally produced control materials analyzed using the validated methods. A

Examining Mercury Transfer in the American Alligator

December 6, 2019
Author(s)
Stephen E. Long, Tracey B. Schock, Nilsen Frances
American alligators are exposed to mercury (Hg) throughout their natural range and may maternally transfer Hg into their eggs. Wildlife species are highly sensitive to Hg toxicity during embryonic development and neonatal life, and information on Hg

Dietary Supplement Laboratory Quality Assurance Program: Exercise O Final Report

September 3, 2019
Author(s)
Charles A. Barber, Melissa M. Phillips, Catherine A. Rimmer, Laura J. Wood, Maria R. Ale, Stephen E. Long, Elizabeth Mudge, Shannon L. Whitehead
The NIST Dietary Supplement Laboratory Quality Assurance Program (DSQAP) was established in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) in 2007 to enable members of the dietary supplement community to

Health Assessment Measurements Quality Assurance Program: Exercise 2 Final Report

May 21, 2019
Author(s)
Charles A. Barber, Jeanice M. Brown Thomas, Carolyn Q. Burdette, Johanna Camara, Stephen E. Long, Melissa M. Phillips, Benjamin J. Place, Catherine A. Rimmer, Laura J. Wood, Lee L. Yu
The NIST Health Assessment Measurements Quality Assurance Program (HAMQAP) was launched in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) in 2017. HAMQAP was established to enable laboratories to improve the

Examining American Alligators as Sentinels of Toxic Trace Element Exposure in Human Populations

April 15, 2019
Author(s)
Frances Nilsen, Thomas Rainwater, Stephen E. Long, Tracey Johnston, Philip Wilkinson, Arnold Brunell, Brittany Kassim, John A. Bowden
Mercury (Hg) is a ubiquitous toxic element eliciting a myriad of health problems including Minamata disease. Exposure to methylmercury, the most toxic bioaccumulative form of Hg, occurs through aquatic dietary sources. Many nations have consumption

Health Assessment Measurements Quality Assurance Program: Exercise 1 Final Report

November 19, 2018
Author(s)
Chuck Barber, Bruce A. Benner Jr., Jeanice M. Brown Thomas, Carolyn Burdette, Johanna Camara, Stephen E. Long, Jacolin Murray, Melissa M. Phillips, Benjamin Place, Kate Rimmer, Laura J. Wood, Susan Tai, Siva K. Chinthalapati, Lee L. Yu
The NIST Health Assessment Measurements Quality Assurance Program (HAMQAP) was launched in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) in 2017. HAMQAP was established to enable laboratories to improve the

Development of a kelp powder (Thallus laminariae) Standard Reference Material

December 9, 2017
Author(s)
Lee L. Yu, Joseph Browning, Carolyn Q. Burdette, George C. Caceres, Kaitlyn Chieh, William C. Davis, MIchael Ellisor, Brittany Kassim, Stephen E. Long, Karen E. Murphy, Rabia Oflaz, Rick L. Paul, Katherine E. Sharpless, Laura J. Wood, James H. Yen, Rolf L. Zeisler
A Standard Reference Material (SRM) of seaweed, SRM 3232 Kelp Powder (Thallus laminariae) has been developed to support food and dietary supplement measurements in compliance with the Food Safety Modernization Act (FSMA) and the Dietary Supplement Health

Analytical Methods and Development of Reference Materials for Toxic Metals and Metal Species in Food and Dietary Supplements

September 18, 2017
Author(s)
Stephen E. Long, Michael B. Ellisor, Frances Nilsen, Laura J. Wood, Karen E. Murphy, Lee L. Yu
Highly toxic metals such as arsenic, cadmium, lead and mercury are prevalent in the terrestrial and marine environments from both natural sources and anthropogenic activities. Contamination of food can often occur during agricultural production and food

Seasonal variation of total mercury burden in the American alligator (Alligator mississippiensis) at Merritt Island National Wildlife Refuge (MINWR), Florida

July 8, 2017
Author(s)
Frances Nilsen, Jonathan E. Dorsey, Stephen E. Long, Tracey B. Schock, John A. Bowden, Russell H. Lowers, Louis J. Guillette Jr.
Seasonal variation of mercury (Hg) is not well studied in free-ranging wildlife. Atmospheric deposition patterns of Hg have been studied in detail and have been modeled for both global and specific locations with great accuracy and correlates to

Trace Element Biodistribution in the American alligator (Alligator mississippiensis)

April 23, 2017
Author(s)
Frances Nilsen, Brittany L. Kassim, Patrick Delaney, Ted Lange, Arnold Brunell, Stephen E. Long, Tracey B. Schock, Louis J. Guillette Jr.
Routine monitoring of contaminant levels in wildlife is an important measure of ecosystem health and also can identify potential human health implications. This is particularly important when the monitored species is recreationally hunted for human

Development of Two Fine Particulate Matter Standard Reference Materials (

April 13, 2016
Author(s)
Michele M. Schantz, Danielle Cleveland, N. Alan Heckert, John Kucklick, Stefan D. Leigh, Stephen E. Long, Jennifer Lynch, Karen E. Murphy, Rabia Oflaz, Adam L. Pintar, Barbara J. Porter, Savelas A. Rabb, Stacy Schuur, Stephen Wise, Rolf L. Zeisler
Two new Standard Reference Materials (SRMs), SRM 2786 Fine Particulate Matter (

Global DNA methylation loss associated with mercury contamination and aging in the American alligator (Alligator mississippiensis)

March 1, 2016
Author(s)
Frances Nilsen, John Bowden, Brittany L. Kassim, Colleen E. Bryan Sallee, Stephen E. Long, Benjamin B. Parrott, Stephen E. Somerville, Ted Lange, Patrick Delaney, Arnold Brunell, Louis J. Guillette
Mercury is a widespread environmental contaminant with exposures eliciting a well-documented catalog of negative outcomes in animals. Yet, our knowledge regarding the underlying mechanisms by which mercury exposures exert these effects remains incomplete

Urinary iodine and stable isotope analysis to examine habitat influences on thyroid hormones among coastal dwelling American alligators

December 9, 2015
Author(s)
Ashley S. Boggs-Russell, Heather J. Hamlin, James C. Nifong, Brittany L. Kassim, Russell H. Lowers, Thomas M. Galligan, Stephen E. Long, Louis J. Guillette Jr.
The American alligator, a freshwater species, is known to forage in marine environments which could lead to increased dietary uptake of iodine, a nutrient necessary for the production of thyroid hormones. To explore the influence of dietary iodine on

Certification of Elements in and Use of Standard Reference Material 3280 Multivitamin/Multielement Tablets

December 2, 2013
Author(s)
Gregory C. Turk, Katherine E. Sharpless, Steven J. Christopher, Danielle Cleveland, Russell D. Day, Stephen E. Long, Elizabeth A. Mackey, Anthony F. Marlow, Rick L. Paul, John R. Sieber, Rabia Oflaz, Laura J. Wood, Lee L. Yu, Rolf L. Zeisler, Stephen A. Wise, James H. Yen, E. Greene, J. Harnly, I-P Ho, Joseph M. Betz, R. Q. Thompson, Candace Jongsma
Standard Reference Material (SRM) 3280 Multivitamin/Multielement Tablets was issued by the National Institute of Standards and Technology (NIST) in 2009 and has certified and reference mass fraction values for 13 vitamins, 26 elements, and 2 carotenoids

Determination of Trace Sulfur in Biodiesel and Diesel Standard Reference Materials by Isotope Dilution Sector Field Inductively Coupled Plasma Mass Spectrometry

November 14, 2013
Author(s)
Steven J. Christopher, Stephen E. Long, Renata Amais, Joaquim N?ga
A method is described for quantification of sulfur at low concentrations on the order of 10 µg g-1 in biodiesel and diesel fuels using double isotope dilution and sector field inductively coupled plasma mass spectrometry (ID-SF-ICP-MS). Closed vessel

Development of a Standard Reference Material for Metabolomics Research

November 4, 2013
Author(s)
Karen W. Phinney, Guillaume Ballihaut, Mary Bedner, Johanna Camara, Steven J. Christopher, William C. Davis, Nathan G. Dodder, Brian E. Lang, Stephen E. Long, Mark S. Lowenthal, Elizabeth A. McGaw, Karen E. Murphy, Bryant C. Nelson, Jocelyn L. Prendergast, Jessica L. Reiner, Catherine A. Rimmer, Lane C. Sander, Michele M. Schantz, Katherine E. Sharpless, Lorna T. Sniegoski, Susan S. Tai, Jeanice M. Brown Thomas, Thomas W. Vetter, Michael J. Welch, Stephen A. Wise, Laura J. Wood, William F. Guthrie, Robert C. Hagwood, Stefan D. Leigh, James H. Yen, Nien F. Zhang, Madhu Chaurhary-Webb, Huiping Chen, Bridgette Haynes, Donna J. LaVoie, Leslie F. McCoy, Shahzad S. Momin, Neelima Paladugula, Elizabeth C. Pendergrast, Christine M. Pfeiffer, Carissa D. Powers, Zia Fazili-Qari, Daniel Rabinowitz, Michael E. Rybak, Rosemary L. Schleicher, Mary Xu, Mindy Zhang, Arthur L. Castle, Brandi S. Benford, Gauthier Eppe

A simple and sensitive HPLC-ICP-MS method for the accurate determination of Vitamin B12 in Fortified Breakfast Cereals and Multivitamin Tablet Reference Materials

April 10, 2013
Author(s)
Siva K. Chinthalapati, Lee L. Yu, John E. Schiel, Stephen E. Long
A sensitive high performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) method has been developed for the determination of vitamin B12. The method was based on efficient isocratic separation with a