A comparison of clinical laboratory data for assigning a consensus value for manganese in a caprine blood reference material.
Biomonitoring for manganese (Mn) exposure is important due to its potential to cause adverse health effects. In this study, we investigate how different sample preparation methods (simple dilution, digestion, volumetric, gravimetric), calibration protocols (aqueous, blood-based, standard additions), and instrumental techniques affect Mn method bias and analytical imprecision. The techniques used included graphite furnace atomic absorption spectrometry (GFAAS), dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS), and sector field (SF-) ICP-MS. We analyzed NIST SRM 1643e Trace Elements in Water and SRM 1598a Inorganic Constituents in Animal Serum (both certified for Mn), and SRM 955c Toxic Metals in Caprine Blood - Level 1 (not certified for Mn). Various matrix effects in ICP-MS produced inaccurate results for SRM 1643e and discrepant results for SRM 955c. In the absence of a certified value for Mn in SRM 955c, we assigned a "consensus" value by combining data from the New York State Department of Health (NYS), the Centers for Disease Control and Prevention (CDC) and the Centre de toxicologie du Québec (CTQ). With this interlaboratory approach, we established an "all-lab" consensus value of 16.3 ± 0.8 μg L-1based on data from DRC-ICP-MS with simple dilution sample preparation and blood-based calibration. We also assigned an "all-method" consensus value of 16.3 ± 0.9 μg L-1based on GFAAS and SF-ICP-MS data from the NYS lab and the DRC-ICP-MS all-lab consensus value. Although the expanded uncertainty (U) calculated for the consensus values may not fully account for all sources of uncertainty, it does show the relative variation that might be expected from one study to the next for the determination of Mn in blood.
Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York Department of Health, P.O. Box 509, Albany, NY 12201-0509, USA ; Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY12201-0509, USA.
Meredith L
ML
Praamsma
Inorganic and Radiation Analytical Toxicology Branch, Centers for Disease Control, 4770 Buford Highway, MS F-18, Atlanta, GA 30341, USA.
Deanna R
DR
Jones
Inorganic and Radiation Analytical Toxicology Branch, Centers for Disease Control, 4770 Buford Highway, MS F-18, Atlanta, GA 30341, USA.
Jeffrey M
JM
Jarrett
Centre de Toxicologie du Québec, Institut National de Santé Publique du Québec, 945 Avenue Wolfe, Québec G1V 5B3, Canada.
Pierre
P
Dumas
Centre de Toxicologie du Québec, Institut National de Santé Publique du Québec, 945 Avenue Wolfe, Québec G1V 5B3, Canada.
Ciprian Mihai
CM
Cirtiu
Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York Department of Health, P.O. Box 509, Albany, NY 12201-0509, USA ; Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY12201-0509, USA.
Patrick J
PJ
Parsons