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Niture S, Gadi S, Qi Q, Rios-Colon L, Khatiwada S, Vandana, Fernando RA, Levine KE, Kumar D. Cyanotoxins Increase Cytotoxicity and Promote Nonalcoholic Fatty Liver Disease Progression by Enhancing Cell Steatosis. Toxins (Basel) 2023; 15:411. [PMID: 37505679 PMCID: PMC10467139 DOI: 10.3390/toxins15070411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 07/29/2023] Open
Abstract
Freshwater prokaryotic cyanobacteria within harmful algal blooms produce cyanotoxins which are considered major pollutants in the aquatic system. Direct exposure to cyanotoxins through inhalation, skin contact, or ingestion of contaminated drinking water can target the liver and may cause hepatotoxicity. In the current study, we investigated the effect of low concentrations of cyanotoxins on cytotoxicity, inflammation, modulation of unfolded protein response (UPR), steatosis, and fibrosis signaling in human hepatocytes and liver cell models. Exposure to low concentrations of microcystin-LR (MC-LR), microcystin-RR (MC-RR), nodularin (NOD), and cylindrospermopsin (CYN) in human bipotent progenitor cell line HepaRG and hepatocellular carcinoma (HCC) cell lines HepG2 and SK-Hep1 resulted in increased cell toxicity. MC-LR, NOD, and CYN differentially regulated inflammatory signaling, activated UPR signaling and lipogenic gene expression, and induced cellular steatosis and fibrotic signaling in HCC cells. MC-LR, NOD, and CYN also regulated AKT/mTOR signaling and inhibited autophagy. Chronic exposure to MC-LR, NOD, and CYN upregulated the expression of lipogenic and fibrosis biomarkers. Moreover, RNA sequencing (RNA seq) data suggested that exposure of human hepatocytes, HepaRG, and HCC HepG2 cells to MC-LR and CYN modulated expression levels of several genes that regulate non-alcoholic fatty liver disease (NAFLD). Our data suggest that low concentrations of cyanotoxins can cause hepatotoxicity and cell steatosis and promote NAFLD progression.
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Affiliation(s)
- Suryakant Niture
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Sashi Gadi
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Qi Qi
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Leslimar Rios-Colon
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Sabin Khatiwada
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Vandana
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Reshan A. Fernando
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, NC 27707, USA
| | - Keith E. Levine
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, NC 27707, USA
| | - Deepak Kumar
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
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Niture S, Gadi S, Lin M, Qi Q, Niture SS, Moore JT, Bodnar W, Fernando RA, Levine KE, Kumar D. Cadmium modulates steatosis, fibrosis, and oncogenic signaling in liver cancer cells by activating notch and AKT/mTOR pathways. Environ Toxicol 2023; 38:783-797. [PMID: 36602393 DOI: 10.1002/tox.23731] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 12/17/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
Cadmium (Cd) is an environmental pollutant that increases hepatotoxicity and the risk of liver diseases. In the current study, we investigated the effect of a physiologically relevant, low concentration of Cd on the regulation of liver cancer cell proliferation, steatosis, and fibrogenic/oncogenic signaling. Exposure to low concentrations of Cd increased endogenous reactive oxygen species (ROS) production and enhanced cell proliferation in a human bipotent progenitor cell line HepaRG and hepatocellular carcinoma (HCC) cell lines. Acute exposure of Cd increased Jagged-1 expression and activated Notch signaling in HepaRG and HCC cells HepG2 and SK-Hep1. Cd activated AKT/mTOR signaling by increasing phosphorylation of AKT-S473 and mTOR-S-4448 residues. Moreover, a low concentration of Cd also promoted cell steatosis and induced fibrogenic signaling in HCC cells. Chronic exposure to low concentrations of Cd-activated Notch and AKT/mTOR signaling induced the expression of pro-inflammatory cytokines tumor necrosis factor-alpha (TNFα) and its downstream target TNF-α-Induced Protein 8 (TNFAIP8). RNA-Seq data revealed that chronic exposure to low concentrations of Cd modulated the expression of several fatty liver disease-related genes involved in cell steatosis/fibrosis in HepaRG and HepG2 cells. Collectively, our data suggest that low concentrations of Cd modulate steatosis along with fibrogenic and oncogenic signaling in HCC cells by activating Notch and AKT/mTOR pathways.
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Affiliation(s)
- Suryakant Niture
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, North Carolina, USA
| | - Sashi Gadi
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
| | - Minghui Lin
- The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, China
| | - Qi Qi
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
| | - Samiksha S Niture
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
| | - John T Moore
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
| | - Wanda Bodnar
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, North Carolina, USA
| | - Reshan A Fernando
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, North Carolina, USA
| | - Keith E Levine
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, North Carolina, USA
| | - Deepak Kumar
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University Durham, North Carolina, USA
- NCCU-RTI Center for Applied Research in Environmental Sciences (CARES), RTI International, Durham, North Carolina, USA
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Waidyanatha S, Black SR, Witt KL, Fennell TR, Swartz C, Recio L, Watson SL, Patel P, Fernando RA, Rider CV. The common indoor air pollutant α-pinene is metabolized to a genotoxic metabolite α-pinene oxide. Xenobiotica 2022; 52:301-311. [PMID: 35473450 DOI: 10.1080/00498254.2022.2070047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
1. α-Pinene caused a concentration-responsive increase in bladder hyperplasia and decrease in sperm counts in rodents following inhalation exposure. Additionally, it formed a prospective reactive metabolite, α-pinene oxide.2. To provide human relevant context for data generated in animal models and explore potential mechanism, we undertook studies to investigate the metabolism of α-pinene to α-pinene oxide and mutagenicity of α-pinene and α-pinene oxide.3. α-Pinene oxide was formed in rat and human microsomes and hepatocytes with some species differences. Based on area under the concentration versus time curves, the formation of α-pinene oxide was up to 4-fold higher in rats than in humans.4. While rat microsomes cleared α-pinene oxide faster than human microsomes, the clearance of α-pinene oxide in hepatocytes was similar between species.5. α-Pinene was not mutagenic with or without induced rat liver S9 in Salmonella typhimurium or Escherichia coli when tested up to 10,000 μg/plate while α-pinene oxide was mutagenic at ≥25 μg/plate.6. α-Pinene was metabolized to α-pinene oxide under the conditions of the bacterial mutation assay although the concentration was approximately 3-fold lower than the lowest α-pinene oxide concentration that was positive in the assay, potentially explaining the lack of mutagenicity observed with α-pinene.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | - Kristine L Witt
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | - Carol Swartz
- Integrated Laboratory Systems, Research Triangle Park, NC, USA
| | - Leslie Recio
- Integrated Laboratory Systems, Research Triangle Park, NC, USA
| | | | - Purvi Patel
- RTI International, Research Triangle Park, NC, USA
| | | | - Cynthia V Rider
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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Harrington JM, Poitras EP, Weber FX, Fernando RA, Liyanapatirana C, Robinson VG, Levine KE, Waidyanatha S. Validation of Analytical Method for Determination of Thallium in Rodent Plasma and Tissues by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). ANAL LETT 2022; 55:1269-1280. [PMID: 35571259 PMCID: PMC9103374 DOI: 10.1080/00032719.2021.1993876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Thallium (Tl) can be released as a byproduct of smelting, mining, and other industries, causing human exposure. There are knowledge gaps on the toxicity of thallium compounds, so the National Toxicology Program is investigating the toxicity of thallium (I) sulfate in rodents. We developed and validated a method to quantitate Tl in rodent plasma and secondary matrices. Primary matrix standards and validation samples were digested with nitric acid and analyzed for Tl by inductively-coupled plasma - mass spectrometry (ICP-MS). Method performance was validated for linearity, accuracy, precision, and other criteria. Calibration was linear from 1.25 to 500 ng Tl/mL plasma; accuracy (RE) was -5.9 to 2.6% for all calibration standards. The lower limit of quantitation (LLOQ) was 1.25 ng Tl/mL plasma, and the limit of detection was 0.0370 ng Tl/mL plasma. Intra- and interday RE and precision (RSD) were -5.6 to -1.7% and ≤0.8% (intraday) and -4.8 to -1.3% and ≤4.3% (interday), respectively, at three sample concentration levels. Standards up to 10.0 × 103 ng/mL could be analyzed by dilution with digested blank matrix, with -6.4% RE and 5.4% RSD. Method was also evaluated in post-natal day 4 (PND4) Hsd:Sprague Dawley SD (HSD) dam and pup plasma, gestation day 18 (GD 18) HSD rat fetal homogenate, HSD rat urine, female HSD rat brain homogenate, female B6C3F1 mouse plasma. Background Tl was detected in control fetal and brain homogenates and urine at < 30% of LLOQ response. Results demonstrate that the method is suitable for determination of Tl in rodent matrices for toxicology studies.
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Affiliation(s)
- James M. Harrington
- RTI International, Research Triangle Park, NC, United States,† Corresponding author, Phone: 919-541-8777,
| | - Eric P. Poitras
- RTI International, Research Triangle Park, NC, United States
| | - Frank X. Weber
- RTI International, Research Triangle Park, NC, United States
| | | | | | - Veronica G. Robinson
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Keith E. Levine
- RTI International, Research Triangle Park, NC, United States
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
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Harrington JM, Haines LG, Essader AS, Liyanapatirana C, Poitras EA, Weber FX, Levine KE, Fernando RA, Robinson VG, Waidyanatha S. Quantitation of Total Vanadium in Rodent Plasma and Urine by Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). ANAL LETT 2021; 54:2777-2788. [PMID: 34898679 DOI: 10.1080/00032719.2021.1890107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Human exposure to vanadium (V) is anticipated because it is a drinking water contaminant. Due to limited data on soluble V salts, the National Toxicology Program is investigating the toxicity in rodents following drinking water exposure. Measurement of internal V dose allows for interpretation of toxicology data. The objective of this study was to develop and validate an inductively coupled plasma-mass spectrometric method to quantitate total V in rat plasma. The method was linear (r ≥ 0.99) from 5.00 - 1,000 ng V/mL. Intra- and inter-day relative error (% RE) and relative standard deviation (% RSD) of spiked plasma samples were 8.5% - 15.6% RE and ≤ 1.8% RSD and 7.3% - 11.7% RE and ≤ 3.1% RSD, respectively. The limit of detection was 0.268 ng V/mL plasma and absolute percent recovery was 113%. Standards up to 7,500 ng V/mL plasma were diluted into the validated range (5.6% RE, 0.9% RSD). V in extracted plasma samples over 15 days at ambient and refrigerated conditions was from 97.7 - 126% of day 0. Determined plasma V concentrations after three freeze-thaw cycles and after frozen storage for up to 63 days ranged from 100 - 106% and 100 - 122% of day 0, respectively. The method was extended to rat urine (accuracy and precision -2.0 - 0.3% RE and <0.6% RSD, respectively for same linear range). These data demonstrate that the method is suitable to quantitate V in rat plasma and urine.
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Affiliation(s)
| | - Laura G Haines
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | - Amal S Essader
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | | | - Eric A Poitras
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | - Frank X Weber
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | - Keith E Levine
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | - Reshan A Fernando
- Analytical Sciences, RTI International, Research Triangle Park, NC, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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Waidyanatha S, Fletcher BL, Fernando RA, Cora MC, Silinski MAR. Development and validation of an ultraperformance liquid chromatography-tandem mass spectrometry method for quantitation of total 3,3',5-triiodo-L-thyronine and 3,3',5,5'-tetraiodo-L-thyronine in rodent serum. ANAL LETT 2021; 55:796-811. [PMID: 35812014 PMCID: PMC9269981 DOI: 10.1080/00032719.2021.1967969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 08/10/2021] [Indexed: 01/03/2023]
Abstract
Many environmental chemicals are known to disrupt thyroid function. Measurement of thyroid hormones in animal studies provides useful information to understand the effects of environmental chemicals on thyroid hormone metabolism. We report an efficient method, utilizing a protein precipitation followed by ultraperformance liquid chromatography-tandem mass spectrometry analysis, to quantitate total 3,3',5-triiodo-L-thyronine (triiodothyronine, T3) and total 3,3',5,5'-tetraiodo-L-thyronine (thyroxine, T4) in rodent serum. The use of synthetic serum for calibration standards eliminated the interferences from endogenous total T3 and T4 and allowed the experimental lower limits of quantitation (LOQ) to be set at the required concentration (T3, 20 ng/dL; T4, 0.5 μg/dL) to allow quantitation of endogenous concentrations. The method was linear (r>0.99; range 20.0-600 ng/dL T3, 0.500-15 μg/dL T4) with good assay recoveries (90.4-107%) for both analytes. Intra- and inter-day accuracy, estimated as percent relative error, were ≤ ±7.6% and intra- and inter-day precision, estimated as the relative standard deviation, were ≤ 5.3% for both analytes. The method may easily be adapted to a well-plate format thereby further improving the efficiency. Total T3 and T4 concentrations were stable in male and female rat and mouse serum when stored in the freezer (~ -70 °C) for up to 62 d with determined values within 92.8-111% of day 0 for both analytes. The method can be extended to quantitate total T3 and T4 concentrations in humans or other species with minimal optimization.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
| | | | | | - Michelle C. Cora
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
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Niture S, Lin M, Qi Q, Moore JT, Levine KE, Fernando RA, Kumar D. Role of Autophagy in Cadmium-Induced Hepatotoxicity and Liver Diseases. J Toxicol 2021; 2021:9564297. [PMID: 34422041 PMCID: PMC8371627 DOI: 10.1155/2021/9564297] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 07/12/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022] Open
Abstract
Cadmium (Cd) is a toxic pollutant that is associated with several severe human diseases. Cd can be easily absorbed in significant quantities from air contamination/industrial pollution, cigarette smoke, food, and water and primarily affects the liver, kidney, and lungs. Toxic effects of Cd include hepatotoxicity, nephrotoxicity, pulmonary toxicity, and the development of various human cancers. Cd is also involved in the development and progression of fatty liver diseases and hepatocellular carcinoma. Cd affects liver function via modulation of cell survival/proliferation, differentiation, and apoptosis. Moreover, Cd dysregulates hepatic autophagy, an endogenous catabolic process that detoxifies damaged cell organelles or dysfunctional cytosolic proteins through vacuole-mediated sequestration and lysosomal degradation. In this article, we review recent developments and findings regarding the role of Cd in the modulation of hepatotoxicity, autophagic function, and liver diseases at the molecular level.
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Affiliation(s)
- Suryakant Niture
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Minghui Lin
- The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan 750021, China
| | - Qi Qi
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - John T. Moore
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
| | - Keith E. Levine
- RTI International, Research Triangle Park, Durham, NC 27709, USA
| | | | - Deepak Kumar
- Julius L. Chambers Biomedical Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
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Rehder Silinski MA, Gilliam JA, Fernando RA, Robinson VG, Germolec D, Cunny H, Huang MC, Furr J, Waidyanatha S. Development of an Analytical Method for Quantitation of Deoxynivalenol by UPLC-MS-MS: A Preliminary Assessment of Gestational and Lactational Transfer in Rats. J Anal Toxicol 2021; 45:566-572. [PMID: 32886793 DOI: 10.1093/jat/bkaa119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/06/2020] [Accepted: 08/31/2020] [Indexed: 01/08/2023] Open
Abstract
Deoxynivalenol (DON) is the most widely distributed trichothecene mycotoxin in grain-based foods and animal feed. Exposure to DON is widespread as it has been detected in food sources from around the world. The objective of this work was to develop a method to quantitate DON in biological matrices and apply it in a preliminary assessment of gestational and lactational transfer of DON following exposure of pregnant rats. The method used protein precipitation followed by ultra-performance liquid chromatography-tandem mass spectrometry. The method was evaluated in male Sprague Dawley rat plasma over the concentration range ∼2-1,000 ng/mL. The method was linear (r ≥ 0.99), accurate (mean relative error ≤ ±4.9%) and precise (relative standard deviation ≤ 5.5%). The mean absolute recovery was 85.9%. The limit of detection was 0.35 ng/mL. The method was also evaluated in gestational day (GD) 18 Hsd:Sprague Dawley®SD® dam plasma and fetal homogenate (mean % relative error ≤ ±16.9; % relative standard deviation ≤ 9.5). Concentrations of DON in dam plasma stored at -80°C for at least 29 days and in fetal homogenate for at least 43 days were within 97.9 to 120% of Day 0 concentrations, demonstrating that DON is stable in these matrices. The method was used to quantitate DON in rat maternal plasma, amniotic fluid, GD 18 fetuses and postnatal day (PND) 4 pups following exposure of dams to 0 (control) and 1 mg/kg DON beginning on GD 6 and continuing through gestation and lactation for a preliminary assessment of maternal transfer. In animals exposed to 1 mg/kg/day, similar concentration of DON was found in GD 18 dam plasma and fetuses, demonstrating significant gestational transfer. The concentration of DON in PND 4 dam plasma was similar to that in GD 18 dam plasma. However, DON was not detected in PND 4 pup plasma above the limit of detection of the assay, demonstrating absence of transfer of DON to pups via lactation.
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Affiliation(s)
| | - Jennifer A Gilliam
- RTI International, P.O. Box 12194, Research Triangle Park, NC 27709, USA
| | - Reshan A Fernando
- RTI International, P.O. Box 12194, Research Triangle Park, NC 27709, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
| | - Dori Germolec
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
| | - Helen Cunny
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
| | - Madelyn C Huang
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
| | | | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
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Waidyanatha S, Hackett M, Black SR, Stout MD, Fennell TR, Silinski MR, Watson SL, Licause J, Robinson VG, Sparrow B, Fernando RA, Cooper S, Rider CV. Toxicokinetic evaluation of the common indoor air pollutant, α-pinene, and its potential reactive metabolite, α-pinene oxide, following inhalation exposure in rodents. Toxicol Appl Pharmacol 2021; 418:115496. [PMID: 33744279 PMCID: PMC8336714 DOI: 10.1016/j.taap.2021.115496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 03/10/2021] [Accepted: 03/14/2021] [Indexed: 11/22/2022]
Abstract
The toxicokinetic behavior of α-pinene and its potential reactive metabolite, α-pinene oxide, was investigated following whole body inhalation exposure to 50 and 100 ppm α-pinene in rats and mice for 6 h per day for 7d. In both species and sexes, the maximum blood concentration (Cmax) increased more than proportionally while the increase in area under the concentration time curve (AUC) was proportional to the exposure concentration. When normalized to the calculated dose (D), both Cmax/D (male rats, 12.2-54.5; female rats, 17.4-74.1; male mice, 7.41-14.2; female mice, 6.59-13.0 (ng/mL)/(mg/kg)) and AUC/D (male rats, 28.9-31.1; female rats, 55.8-56.8; male mice, 18.1-19.4; female mice, 19.2-22.5 (h*ng/mL)/(mg/kg)) in rats were higher than in mice and in female rats were higher than in male rats; no sex difference was observed in mice. α-Pinene was eliminated from blood with half-lives between 12.2 and 17.4 h in rats and 6.18-19.4 h in mice. At the low dose, the ratio of α-pinene oxide to α-pinene, based on Cmax and AUC, respectively, was 0.200-0.237 and 0.279-0.615 in rats and 0.060-0.086 and 0.036-0.011 in mice demonstrating lower formation of the oxide in mice than in rats. At the high dose, the ratio decreased considerably in both species pointing to saturation of pathways leading to the formation of α-pinene oxide. α-Pinene and the oxide were quantified in the mammary glands of rats and mice with tissue to blood ratios of ≥23 demonstrating retention of these analytes in mammary glands. The findings of epoxide formation and species- and sex-differences in systemic exposure may be important in providing context and relating animal findings to human exposures.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
| | | | | | - Mathew D Stout
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | | | | | | | - Veronica G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | | | | | - Cynthia V Rider
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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10
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Harrington JM, Haines LG, Levine KE, Liyanapatirana C, Essader AS, Fernando RA, Robinson VG, Roberts GK, Stout MD, Hooth MJ, Waidyanatha S. Corrigendum to "Internal dose of vanadium in rats following repeated exposure to vanadyl sulfate and sodium orthovanadate via drinking water" [Toxicology and Applied Pharmacology 412 (2021) 115395]. Toxicol Appl Pharmacol 2021; 423:115546. [PMID: 33905758 DOI: 10.1016/j.taap.2021.115546] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Laura G Haines
- RTI International, Research Triangle Park, NC, United States
| | - Keith E Levine
- RTI International, Research Triangle Park, NC, United States
| | | | - Amal S Essader
- RTI International, Research Triangle Park, NC, United States
| | | | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Georgia K Roberts
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Matthew D Stout
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Michelle J Hooth
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States.
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Shipkowski KA, Cora MC, Cesta MF, Robinson VG, Waidyanatha S, Witt KL, Vallant MK, Fallacara DM, Hejtmancik MR, Masten SA, Cooper SD, Fernando RA, Blystone CR. Comparison of sulfolane effects in Sprague Dawley rats, B6C3F1/N mice, and Hartley guinea pigs after 28 days of exposure via oral gavage. Toxicol Rep 2021; 8:581-591. [PMID: 33777704 PMCID: PMC7985713 DOI: 10.1016/j.toxrep.2021.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 01/27/2023] Open
Abstract
Sulfolane is a solvent used in industrial refining with identified environmental exposure in drinking water. Due to potential large species differences, the National Toxicology Program (NTP) conducted 28-day toxicity studies in male and female Hsd:Sprague Dawley® SD® rats, B6C3F1/N mice, and Hartley guinea pigs. A wide dose range of 0, 1, 10, 30, 100, 300, and 800 mg/kg was administered via gavage. Histopathology, clinical pathology, and organ weights were evaluated after 28 days of exposure. In addition, plasma concentrations of sulfolane were evaluated 2 and 24 h after the last dose. Increased mortality was observed in the highest dose group of guinea pigs and mice while decreased body weight was observed in rats compared to controls. Histopathological lesions were observed in the kidney (male rat), stomach (male mice), esophagus (male and female guinea pigs), and nose (male guinea pigs). Plasma concentrations were generally higher in rats and guinea pigs compared to mice with evidence of saturated clearance at higher doses. Male rats appear to be the most sensitive with hyaline droplet accumulation occurring at all doses, although the human relevance of this finding is questionable.
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Affiliation(s)
- K A Shipkowski
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - M C Cora
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - M F Cesta
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - V G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - S Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - K L Witt
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - M K Vallant
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | | | - S A Masten
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - S D Cooper
- RTI International, Research Triangle Park, NC, USA
| | - R A Fernando
- RTI International, Research Triangle Park, NC, USA
| | - C R Blystone
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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12
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Harrington JM, Haines LG, Levine KE, Liyanapatirana C, Essader AS, Fernando RA, Robinson VG, Roberts GK, Stout MD, Hooth MJ, Waidyanatha S. Internal dose of vanadium in rats following repeated exposure to vanadyl sulfate and sodium orthovanadate via drinking water. Toxicol Appl Pharmacol 2021; 412:115395. [PMID: 33421504 PMCID: PMC8631130 DOI: 10.1016/j.taap.2021.115395] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/28/2020] [Accepted: 12/31/2020] [Indexed: 11/24/2022]
Abstract
Vanadium is a ubiquitous environmental contaminant that exists in multiple oxidation states. Humans are exposed to vanadyl (V4+) and vanadate (V5+) from dietary supplements, food, and drinking water and hence there is a concern for adverse human health. The current investigation is aimed at identifying vanadium oxidation states in vitro and in vivo and internal concentrations following exposure of rats to vanadyl sulfate (V4+) or sodium metavanadate (V5+) via drinking water for 14 d. Investigations in simulated gastric and intestinal fluids showed that V4+ was stable in gastric fluid while V5+ was stable in intestinal fluid. Analysis of rodent plasma showed that the only vanadium present was V4+, regardless of the exposed compound suggesting conversion of V5+ to V4+ in vivo and/or instability of V5+ species in biological matrices. Plasma, blood, and liver concentrations of total vanadium, after normalizing for vanadium dose consumed, were higher in male and female rats following exposure to V5+ than to V4+. Following exposure to either V4+ or V5+, the total vanadium concentration in plasma was 2- to 3-fold higher than in blood suggesting plasma as a better matrix than blood for measuring vanadium in future work. Liver to blood ratios were 4-7 demonstrating significant tissue retention following exposure to both compounds. In conclusion, these data point to potential differences in absorption and disposition properties of V4+ and V5+ salts and may explain the higher sensitivity in rats following drinking water exposure to V5+ than V4+ and highlights the importance of internal dose determination in toxicology studies.
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Affiliation(s)
| | - Laura G Haines
- RTI International, Research Triangle Park, NC, United States
| | - Keith E Levine
- RTI International, Research Triangle Park, NC, United States
| | | | - Amal S Essader
- RTI International, Research Triangle Park, NC, United States
| | | | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Georgia K Roberts
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Matthew D Stout
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Michelle J Hooth
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, NC, United States.
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13
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Fernando RA, Fennell TR, Watson SL, Silinski MAR, Blake JC, Robinson VG, Waidyanatha S. Development and Validation of an Analytical Method for Quantitation of Alpha-Pinene Oxide in Rodent Blood and Mammary Gland by GC-MS. J Anal Toxicol 2021; 46:270-276. [PMID: 33438723 DOI: 10.1093/jat/bkab007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/30/2020] [Accepted: 01/12/2021] [Indexed: 11/13/2022] Open
Abstract
Alpha-pinene is a monoterpene found in the oil of coniferous trees and has a wide variety of applications. Alpha pinene oxide is a potential reactive metabolite of alpha-pinene in rodents. The objective of this work is to validate a gas chromatography-mass spectrometry method to quantitate alpha pinene oxide in rat and mouse blood and mammary gland in support of studies investigating the toxicity and toxicokinetic behavior of alpha-pinene. The method was validated in male Sprague Dawley rat blood over the concentration range 5 to 250 ng/mL. Matrix standard curves were linear (r ≥ 0.99), and accuracy (percent relative error %RE) was ≤ ±15% for standards at all levels. Intra- and inter-day precision (% relative standard deviation, RSD) and accuracy (%RE) were evaluated at three concentration levels (10, 50, and 200 ng/mL) and were ≤ 6.3% and ≤ ±5.4%, respectively. The limit of detection, determined from the SD of the limit of quantitation (5 ng/mL), was 1.06 ng/mL. Standards as high as 25,000 ng/mL could be accurately quantified after diluting into the validated range (%RE ≤ ±7.1%; RSD ≤5.8%). Alpha pinene oxide was stable in rat blood for at least 70 days in frozen storage (-80 °C). Alpha pinene oxide could accurately be quantified in male and female Hsd:Sprague Dawley®SD® rat and B6C3F1 mouse blood (mean %RE ≤ ±5.3%; %RSD ≤7.8%) and female B6C3F1 and SD rat mammary gland (mean %RE ≤ ±14.6%; %RSD ≤8.1%) using primary matrix standard curve. These results demonstrate that the method is suitable for the analysis of alpha pinene oxide in rodent blood and mammary gland generated from toxicokinetic and toxicology studies.
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Affiliation(s)
| | | | - Scott L Watson
- RTI International, Research Triangle Park, P.O. Box 12194, NC 27709
| | | | - James C Blake
- RTI International, Research Triangle Park, P.O. Box 12194, NC 27709
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, P.O. Box 12233, NC 27709
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, Research Triangle Park, P.O. Box 12233, NC 27709
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14
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Rehder Silinski MA, Fletcher BL, Fernando RA, Robinson VG, Waidyanatha S. Development and Validation of an Analytical Method for Quantitation of Bisphenol S in Rodent Plasma, Amniotic Fluid and Fetuses by UPLC-MS-MS. J Anal Toxicol 2021; 46:277-284. [PMID: 33512500 DOI: 10.1093/jat/bkab008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 12/15/2020] [Accepted: 01/08/2021] [Indexed: 11/12/2022] Open
Abstract
Bisphenol S (BPS) has been detected in personal care products, water, food and indoor house dust, demonstrating the potential for human exposure. Due to limited data to characterize the hazard of BPS, the National Toxicology Program (NTP) is investigating the toxicity of BPS in rodent models. Generating systemic exposure data is integral to putting toxicological findings into context. The objective of this work was to develop and validate a method to quantitate free (unconjugated parent) and total (free and all conjugated forms of) BPS in rodent plasma, amniotic fluid and fetal homogenate in support of NTP studies. The method used incubation with (total BPS) and without (free BPS) deconjugating enzyme and then protein precipitation followed by ultra-performance liquid chromatography-tandem mass spectrometry. In Sprague Dawley rat plasma, the method was linear (r ≥ 0.99) over the range 5-1,000 ng/mL, accurate (mean relative error (RE) ≤ ±10.5%) and precise (relative standard deviation (RSD) ≤ 7.7%). Mean recoveries were ≥93.1% for both free and total analyses. The limits of detection were 1.15 ng/mL (free) and 0.862 ng/mL (total) in plasma. The method was evaluated in the following study matrices: (i) male Hsd:Sprague Dawley®SD® (HSD) rat plasma, (ii) female HSD rat plasma, (iii) male B6C3F1 mouse plasma, (iv) female B6C3F1 mouse plasma, (v) HSD rat gestational day (GD) 18 dam plasma, (vi) HSD rat GD 18 amniotic fluid, (vii) HSD rat GD 18 fetal homogenate and (viii) HSD rat postnatal day 4 pup plasma (mean %RE ≤ ±8.2 and %RSD ≤ 8.7). Stability of BPS in extracted samples was demonstrated for up to 7 days at various temperatures, and freeze-thaw stability was demonstrated after three cycles over 7 days. BPS in various matrices stored at -80°C for at least 60 days was within 92.1-115% of Day 0 concentrations, demonstrating its stability in these matrices. These data demonstrate that this simple method is suitable for determination of free and total BPS in plasma, amniotic fluid and fetuses following exposure of rodents to BPS.
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Affiliation(s)
| | - Brenda L Fletcher
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, NC 27709, USA
| | - Reshan A Fernando
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, NC 27709, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709, USA
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15
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Silinski MAR, Licause J, Uenoyama T, Blake JC, Fernando RA, Robinson VG, Waidyanatha S. Development and Validation of an Analytical Method for Quantitation of Alpha-pinene in Rodent Blood and Mammary Gland by Headspace GC-MS. J Anal Toxicol 2020; 46:bkaa195. [PMID: 33336684 PMCID: PMC8866827 DOI: 10.1093/jat/bkaa195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/20/2020] [Accepted: 12/17/2020] [Indexed: 11/13/2022] Open
Abstract
Alpha-pinene (AP), produced by pine trees and other plants, is the main component of turpentine and is used as a fragrance and flavor ingredient. Exposure occurs via use of personal care and household cleaning products and in the lumber industry. Despite widespread exposure, toxicity data for AP are limited. The objective of this work was to develop and validate a method to quantitate AP in rodent blood and mammary glands, in support of toxicokinetic and toxicology studies of AP. The method uses 100 µL of blood or ~100 mg of mammary gland with analysis by headspace gas chromatography-mass spectrometry. The samples are diluted with internal standard (2H3-AP, IS) and sealed in headspace vials; mammary glands are homogenized within the vial. The vials are equilibrated briefly at 60°C before a headspace sample is analyzed. The method was validated in Sprague Dawley rat blood over the range 5-500 ng/mL and mammary gland over the range 100-5000 ng/g. The method was linear (r ≥0.99), accurate (mean relative error (RE) ≤±13.4%) and precise (relative standard deviation (RSD) ≤7.1%) in both matrices. Recoveries incorporating IS were ≥88.7% at all concentrations in both tissues. Standards as high as 1500 ng/mL in blood and 20,000 ng/g in mammary gland could be analyzed using lower injection volume or extrapolating the calibration curve beyond the upper limit of quantitation (mean %RE ≤±18.7; %RSD ≤2.2). Loss of AP occurred during overnight autosampler storage as well as frozen storage in as few as 15 days, but incorporation of IS prior to storage corrected for the loss such that calculated concentrations were within 84.7-117% of day 0 concentrations following frozen storage up to ≥32 days in both matrices. Matrix evaluation was performed in Hsd:Sprague Dawley®SD® rat and B6C3F1 mouse blood and mammary glands (mean %RE ≤±9.2; %RSD ≤4.3). These data demonstrate that the method is suitable for determination of AP in rodent blood and mammary glands.
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Affiliation(s)
- Melanie A Rehder Silinski
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, Durham, NC 27709, USA
| | - Joseph Licause
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, Durham, NC 27709, USA
| | - Teruyo Uenoyama
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, Durham, NC 27709, USA
| | - James C Blake
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, Durham, NC 27709, USA
| | - Reshan A Fernando
- Discovery Sciences Unit, RTI International, P.O. Box 12194, Research Triangle Park, Durham, NC 27709, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, Durham, NC 27709, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, Durham, NC 27709, USA
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16
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Huang MC, Turner KJ, Vallant M, Robinson VG, Lu Y, Price CJ, Fennell TR, Silinski MA, Waidyanatha S, Ryan KR, Black SR, Fernando RA, McIntyre BS. Tolerability and age-dependent toxicokinetics following perinatal hydroxyurea treatment in Sprague Dawley rats. J Appl Toxicol 2020; 41:1007-1020. [PMID: 33241551 PMCID: PMC8144245 DOI: 10.1002/jat.4087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 11/11/2022]
Abstract
Hydroxyurea (HU) is a valuable therapy for individuals with sickle cell anemia. With increased use of HU in children and throughout their lives, it is important to understand the potential effects of HU therapy on their development and fertility. Thus, studies were conducted to identify appropriate doses to examine long‐term effects of prenatal and early postnatal HU exposure and to understand kinetics of HU at various life stages. Pregnant Sprague Dawley dams were administered HU (0–150 mg/kg/day) via oral gavage from gestation days 17 to 21 and during lactation. Pups were dosed with the same dose as their respective dam starting on postnatal day (PND) 10 and up to PND 34. There was minimal maternal toxicity, and no significant effects on littering at any dose of HU. Starting on ~PND 16, offspring displayed skin discoloration and alopecia at doses ≥75 mg/kg/day and lower body weight compared to controls at doses ≥100 mg/kg/day. Gestational transfer of HU was observed, but there was minimal evidence of lactational transfer. Our toxicokinetic studies suggest that the internal dose in offspring may be altered due to age, but not due to sex. The plasma area under the curve, a measure of systemic exposure, at doses tolerated by offspring was threefold to sevenfold lower than the internal therapeutic dose in humans. Therefore, strategies to establish clinically relevant exposures in animal studies are needed. Overall, these data are useful for the design of appropriate nonclinical studies in the future to evaluate the consequences of long‐term HU treatment starting in childhood. Increased use of hydroxyurea (HU) to treat sickle cell disease in children and throughout their lives augments the importance of understanding potential effects of HU on development and fertility. To inform the design of studies to evaluate long‐term safety of HU use in children, tolerability of prenatal and early postnatal HU treatment was evaluated in Sprague Dawley rats. Additionally, studies investigating gestational and lactational transfer of HU and how toxicokinetics of HU vary with age were conducted.
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Affiliation(s)
- Madelyn C Huang
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | | | - Molly Vallant
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | - Yi Lu
- Social and Scientific Services, Durham, North Carolina, USA
| | | | | | | | - Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | - Kristen R Ryan
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | | | | | - Barry S McIntyre
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
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17
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Rehder Silinski MA, Uenoyama T, Fernando RA, Robinson VG, Roberts G, Cunny H, Hubbard T, Waidyanatha S. Development of an Analytical Method for Quantitation of 2,2'-Dimorpholinodiethyl Ether (DMDEE) in Rat Plasma, Amniotic Fluid, and Fetal Homogenate by UPLC-MS-MS for Determination of Gestational and Lactational Transfer in Rats. J Anal Toxicol 2020; 45:1036-1041. [PMID: 33031531 DOI: 10.1093/jat/bkaa158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 09/16/2020] [Accepted: 10/07/2020] [Indexed: 11/13/2022] Open
Abstract
2,2'-Dimorpholinodiethyl ether (DMDEE) is a specialty amine catalyst used in the production of flexible foams, adhesives, and coatings. The potential for occupational exposure to DMDEE is high, but toxicity data are very limited. The objective of this work was to develop a method to quantitate DMDEE in biological matrices to assess gestational and lactational transfer of DMDEE in rats following exposure of dams. The method used protein precipitation, followed by removal of phospholipids and analysis of supernatant by ultra-performance liquid chromatography-tandem mass spectrometry. Rat fetuses were homogenized in water prior to protein precipitation and delipidation procedures. The method was evaluated in male Sprague Dawley (SD) rat plasma over the concentration range 5 to 1000 ng/mL. The method was linear (r ≥ 0.99), accurate (mean relative error (RE) ≤ ± 11.9%) and precise (relative standard deviation (RSD) ≤ 2.7%). The mean absolute recovery was 106%. The limit of detection (LOD) was 0.262 ng/mL. Standards as high as ~ 100,000 ng/mL could be successfully diluted into the calibration range (mean %RE = -14.9; %RSD = 0.5). The method was evaluated in SD rat dam plasma, post-natal day (PND) 4 pup plasma, gestational day (GD) 18 amniotic fluid and fetal homogenate (mean %RE ≤ ± 11.9; %RSD ≤ 2.3). Concentrations of DMDEE in rat dam plasma, amniotic fluid, and fetal homogenate stored for at least 29 days and in pup plasma for at least 18 days at -80°C were within 87.7 to 99.5% of Day 0 concentrations, demonstrating that DMDEE is stable in these matrices. The method was used to quantitate DMDEE in rat plasma, amniotic fluid, and fetus samples from a dose range finding toxicology study in which dams were dosed via gavage with DMDEE from GD 6 at doses of 0 (control), 62.5 and 250 mg/kg/day. DMDEE concentration increased with the dose in all matrices examined. The concentration in GD 18 fetuses was almost two-fold higher than GD 18 dams demonstrating gestational transfer of DMDEE. However, the concentration in PND 4 pup plasma was more than an order of magnitude lower than corresponding dam plasma suggesting less potential for transfer of DMDEE from dams to pups via lactation. There was no significant difference in concentration for male and female pup plasma.
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Affiliation(s)
| | - Teruyo Uenoyama
- RTI International, P.O. Box 12194, Research Triangle Park, NC 27709
| | | | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
| | - Georgia Roberts
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
| | - Helen Cunny
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
| | - Troy Hubbard
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709
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18
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Waidyanatha S, Black SR, Croutch CR, Collins BJ, Silinski MAR, Kerns S, Sutherland V, Robinson VG, Aillon K, Fernando RA, Mutlu E, Fennell TR. Comparative toxicokinetics of bisphenol S and bisphenol AF in male rats and mice following repeated exposure via feed. Xenobiotica 2020; 51:210-221. [PMID: 32985913 DOI: 10.1080/00498254.2020.1829171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We investigated the plasma toxicokinetic behavior of free (parent) and total (parent and conjugated forms) of bisphenol S (BPS) and bisphenol AF (BPAF) in plasma of adult male rats and mice following exposure via feed for 7 days to BPS (338, 1125, and 3375 ppm) or BPAF (338, 1125, and 3750 ppm). In rats, the exposure concentration-normalized maximum concentration [Cmax/D (ng/mL)/(ppm)] and area under the concentration time curve [AUC/D (h × ng/mL)/(ppm)] for free was higher for BPS (Cmax/D: 0.476-1.02; AUC/D: 3.58-8.26) than for BPAF (Cmax/D: 0.017-0.037; AUC/D:0.196-0.436). In mice, the difference in systemic exposure parameters between free BPS (Cmax/D: 0.376-0.459; AUC/D: 1.52-2.54) and free BPAF (Cmax/D: 0.111-0.165; AUC/D:0.846-1.09) was marginal. Elimination half-lives for free analytes (4.41-10.4 h) were comparable between species and analogues. When systemic exposure to free analyte was compared between species, in rats, BPS exposure was slightly higher but BPAF exposure was much lower than in mice. BPS and BPAF were highly conjugated; total BPS AUC values (rats ≥18-fold, mice ≥17-fold) and BPAF (rats ≥127-fold, mice ≥16-fold) were higher than corresponding free values. Data demonstrated that there are analogue and species differences in the kinetics of BPS and BPAF.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Sherry R Black
- Discovery Sciences, RTI International, Research Triangle Park, NC, USA
| | | | - Bradley J Collins
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | | | - Vicki Sutherland
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | - Reshan A Fernando
- Discovery Sciences, RTI International, Research Triangle Park, NC, USA
| | - Esra Mutlu
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Timothy R Fennell
- Discovery Sciences, RTI International, Research Triangle Park, NC, USA
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19
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Silinski MAR, Fernando RA, Robinson VG, Waidyanatha S. Development and Validation of an Analytical Method for Quantitation of Monobutylphthalate, a Metabolite of Di-n-Butylphthalate, in Rat Plasma, Amniotic Fluid, Fetuses and Pups by UPLC-MS/MS. J Anal Toxicol 2020; 44:370-377. [PMID: 31776566 DOI: 10.1093/jat/bkz090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phthalates have been used for decades as softening agents in the production of plastics, but in recent years have been extensively investigated for their potential hazards to human health and the environment. Di-n-butyl phthalate (DBP), with widespread exposure occurring through a variety of consumer products such as cosmetics and pesticides, is a suspected carcinogen and an endocrine system disruptor in both humans and laboratory animals. Its predominant metabolite is the monoester, monobutyl phthalate (MBP), which can serve as a marker of exposure. To support toxicological studies of DBP in pregnant and lactating rats and their offspring, a novel ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for quantitation of MBP in rat plasma, amniotic fluid, fetuses and whole pup samples. Plasma samples were extracted using a simple protein precipitation with acetonitrile. Extraction and delipidation of pup homogenate was performed using acetonitrile and then submerging the vials in liquid nitrogen. Extracts were analyzed by UPLC-MS/MS in the negative ion mode. The method was successfully validated over the concentration ranges 25-5,000 ng/mL in female Sprague Dawley (SD) rat plasma and 50-5,000 ng/g in SD pup homogenate. Matrix calibration curves were linear (r ≥ 0.99), and the percent relative error (%RE) values were ≤ ±15% for standards at all levels. Absolute recoveries were > 92% in both matrices. The limits of detection (LODs) were 6.9 ng/mL in plasma and 9.4 ng/g in pup homogenate. Acceptable intra- and interday accuracy and precision were demonstrated by mean %RE ≤ ±7.5 and relative standard deviation (%RSD) ≤ 10.1%. Extract stability was demonstrated for ~6 days at various temperatures and freeze-thaw stability was demonstrated after 3 cycles over 3 days. Secondary matrix evaluation was performed for MBP in amniotic fluid and pooled fetus homogenate (mean %RE ≤ ±11.5 and %RSD ≤ 13.7). These data demonstrate that this simple method is suitable for determination of MBP in plasma, amniotic fluid, fetus and pup samples from toxicological studies of DBP.
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Affiliation(s)
- Melanie A Rehder Silinski
- Analytical Sciences, RTI International, P.O. Box 12194, 3040 Cornwallis Rd, Research Triangle Park, NC 27709, USA and
| | - Reshan A Fernando
- Analytical Sciences, RTI International, P.O. Box 12194, 3040 Cornwallis Rd, Research Triangle Park, NC 27709, USA and
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, P.O. Box 12233, 111 TW Alexander Drive, Research Triangle Park, NC 27709, USA
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Waidyanatha S, Black SR, Silinski M, Sutherland V, Fletcher BL, Fernando RA, Fennell TR. Comparative toxicokinetics of bisphenol S in rats and mice following gavage administration. Toxicol Appl Pharmacol 2020; 406:115207. [PMID: 32853628 DOI: 10.1016/j.taap.2020.115207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/12/2020] [Accepted: 08/18/2020] [Indexed: 01/01/2023]
Abstract
Bisphenol S (BPS) is a component of polyether sulfone used in a variety of industrial applications and consumer products. We investigated the plasma toxicokinetic (TK) behavior of free (unconjugated parent) and total (parent and conjugated) BPS in rats and mice following a single gavage administration (34, 110, or 340 mg/kg). In male rats, BPS was rapidly absorbed with free BPS maximum concentration (Cmax) reached at ≤2.27 h. Elimination of free BPS in male rats was dose-dependent with estimated half-lives of 5.77-11.9 h. Cmax and area under the concentration versus time curve (AUC) increased with dose although the increase in AUC was more than dose proportional. In male rats, total BPS Cmax was reached ≤2.77 h with both Cmax (≥ 10-fold) and AUC (≥ 15-fold) higher than free BPS demonstrating rapid and extensive conjugation of BPS. In male mice, the increase in Cmax and AUC of free BPS was dose-proportional; Cmax was higher and AUC was lower than in male rats. BPS was cleared more rapidly in male mice (half-life 2.86-4.21 h) compared to male rats (half-life 5.77-11.9 h). Similar to rats, total BPS Cmax (≥ 6-fold) and AUC (≥ 12-fold) were higher than corresponding free BPS. Oral bioavailability of free BPS was low to moderate (rats, ≤ 21%; mice, ≤ 19%). There were some species differences in TK parameters of free and total BPS and limited sex difference in rats and mice. In addition, there were dose-related effects of plasma TK parameters in rats.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
| | - Sherry R Black
- RTI International, Discovery Sciences, Research Triangle Park, NC, USA
| | - Melanie Silinski
- RTI International, Discovery Sciences, Research Triangle Park, NC, USA
| | - Vicki Sutherland
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Brenda L Fletcher
- RTI International, Discovery Sciences, Research Triangle Park, NC, USA
| | - Reshan A Fernando
- RTI International, Discovery Sciences, Research Triangle Park, NC, USA
| | - Timothy R Fennell
- RTI International, Discovery Sciences, Research Triangle Park, NC, USA
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Silinski MAR, Uenoyama T, Cooper SD, Fernando RA, Robinson VG, Waidyanatha S. Development and Validation of an Analytical Method for Quantitation of Sulfolane in Rat and Mouse Plasma by GC-MS. J Anal Toxicol 2020; 43:477-481. [PMID: 31044244 DOI: 10.1093/jat/bkz031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/19/2019] [Accepted: 04/08/2019] [Indexed: 11/14/2022] Open
Abstract
Sulfolane is an industrial solvent commonly used for extraction of aromatic hydrocarbons in the oil refining process, as well in the purification of natural gas. Its wide use and high solubility in water has led to contamination of groundwater. The objective of this work was to develop and validate an analytical method to quantitate sulfolane in rodent plasma in support of the National Toxicology Program toxicology and toxicokinetic studies of sulfolane. The method uses extraction of plasma with ethyl acetate and analysis by gas chromatography-mass spectrometry with electron ionization. The method was validated in male Sprague Dawley (SD) rat plasma over the concentration range of 20-100,000 ng/mL. The method was linear (r ≥ 0.99), accurate (mean relative error (RE) ≤ ±5.1%) and precise (relative standard deviation (RSD) ≤ 2.9%). The absolute recovery was ≥74%. The limit of detection was 0.516 ng/mL. Standards as high as ~2.5 mg/mL could be successfully diluted into the calibration range (mean %RE ≤ ±4.5; %RSD ≤ 4.6). Extracted samples were stable for at least 3 days at ambient and refrigerated temperatures, and freeze/thaw stability in matrix was demonstrated after three cycles over 3 days (calculated concentrations within 90.8-102% of Day 0 concentrations). Sulfolane was stable in frozen plasma for at least 75 days at -80°C (calculated concentrations within 93.0-98.1% of Day 0 concentrations). Matrix evaluation was performed for sulfolane in female SD rat plasma and male and female B6C3F1 mouse plasma (mean %RE ≤ ±4.9; %RSD ≤ 3.3). These data demonstrate that the method is suitable for determination of sulfolane in rodent plasma.
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Affiliation(s)
| | - Teruyo Uenoyama
- RTI International, PO Box 12194, Research Triangle Park, NC 27709, USA
| | - Stephen D Cooper
- RTI International, PO Box 12194, Research Triangle Park, NC 27709, USA
| | - Reshan A Fernando
- RTI International, PO Box 12194, Research Triangle Park, NC 27709, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, NIEHS, PO Box 12233, Research Triangle Park, NC 27709, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, NIEHS, PO Box 12233, Research Triangle Park, NC 27709, USA
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Waidyanatha S, Black SR, Fennell TR, Watson SL, Patel PR, Cooper SD, Blake J, Robinson VG, Fernando RA, Blystone CR. Toxicokinetics and bioavailability of sulfolane, a ground water contaminant, following oral and intravenous administration in rodents: A dose, species, and sex comparison. Toxicol Appl Pharmacol 2019; 379:114690. [PMID: 31344372 DOI: 10.1016/j.taap.2019.114690] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/18/2019] [Accepted: 07/21/2019] [Indexed: 01/29/2023]
Abstract
Sulfolane is a ground water contaminant near refinery sites. The objective of this work was to investigate the toxicokinetics and bioavailability of sulfolane in male and female Harlan Hsd:Sprague Dawley® SD® rats and B6C3F1/N mice following a single oral administration of 10, 30, or 100 mg/kg. Sulfolane was rapidly absorbed in rats with the maximum plasma concentration, Cmax, reached at ≤1.47 h. Although Cmax increased proportionally to the dose, the half-life of elimination increased with the dose and the area under the concentration versus time curve (AUC) increased more than proportionally to the dose. In male and female rats, plasma elimination half-life increased with the dose from 1.97 to 6.33 h. Absorption of sulfolane in mice following oral administration was more rapid than in rats with Cmax reached at ≤0.55 h. In addition, mice had a shorter half-life (≤ 1.25 h) and a lower AUC than rats. In male and female mice, both Cmax and AUC increased more than proportionally to the dose. Bioavailability of sulfolane was higher in rats (81-83%) than mice (59-63%) at 10 mg/kg; at 30 and 100 mg/kg, bioavailability >100% in both species and sexes suggesting that the saturation of metabolism and clearance processes of sulfolane may begin at a single oral dose of ~30 mg/kg. There was no apparent sex difference in toxicokinetic parameters of sulfolane in rats and mice. These data demonstrate that sulfolane was well-absorbed following oral administration with high bioavailability in rats and mice with some species differences, but no sex difference.
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Affiliation(s)
- Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States of America.
| | - Sherry R Black
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Timothy R Fennell
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Scott L Watson
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Purvi R Patel
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Stephen D Cooper
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - James Blake
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Veronica Godfrey Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States of America
| | - Reshan A Fernando
- RTI International, Discovery Sciences, Research Triangle Park, NC, United States of America
| | - Chad R Blystone
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States of America
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23
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Levine KE, Collins BJ, Stout MD, Wyde M, Afton SE, Essader AS, Ennis TJ, Amato KE, McWilliams AC, Fletcher BL, Fernando RA, Harrington JM, Catlin N, Robinson VG, Waidyanatha S. Characterization of Zinc Carbonate Basic as a Source of Zinc in a Rodent Study Investigating the Effects of Dietary Deficiency or Excess. ANAL LETT 2017; 50:2447-2464. [PMID: 30930463 DOI: 10.1080/00032719.2017.1293073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Zinc deficiency and excess can result in adverse health outcomes. There is conflicting evidence regarding whether excess or deficient zinc in the diet can contribute to carcinogenicity. The objective of this study was to characterize zinc carbonate basic for use as a source of dietary zinc in a rodent toxicity and carcinogenicity study investigating the effects of zinc deficiency and excess. Because of the complex chemistries of zinc carbonate basic compounds, inconsistent nomenclature, and literature and reference spectra gaps, it was necessary to employ multiple analytical techniques, including Karl Fischer titration, combustion analysis, inductively coupled plasma-optical emission spectrometry, X-ray diffraction, infrared spectroscopy, X-ray fluorescence spectrometry, and thermogravimetric analysis to characterize the test article. Based on the collective evidence and through the process of elimination, the test article was found to be composed mainly of zinc carbonate basic with zinc oxide as a minor component. The zinc content was determined to be 56.6% (w/w) with heavy metals such as arsenic, cadmium, mercury and lead below the limit of quantitation of less than or equal to 0.01%. The test material was stable at ambient temperature. Based on the work described in this manuscript, the test article was suitable for use as a source of zinc in studies of deficiency and excess in the diet.
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Affiliation(s)
- Keith E Levine
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Bradley J Collins
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Matthew D Stout
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Michael Wyde
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Scott E Afton
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Amal S Essader
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Todd J Ennis
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Kelly E Amato
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Andrea C McWilliams
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Brenda L Fletcher
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Reshan A Fernando
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - James M Harrington
- RTI International, 3040 E. Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC, 27709, USA
| | - Natasha Catlin
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Veronica G Robinson
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Suramya Waidyanatha
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, MD EC-06, P.O. Box 12233, 111 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
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24
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Levine KE, Young DJ, Afton SE, Harrington JM, Essader AS, Weber FX, Fernando RA, Thayer K, Hatch EE, Robinson VG, Waidyanatha S. Development, validation, and application of an ultra-performance liquid chromatography-sector field inductively coupled plasma mass spectrometry method for simultaneous determination of six organotin compounds in human serum. Talanta 2015; 140:115-121. [PMID: 26048832 DOI: 10.1016/j.talanta.2015.03.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 03/15/2015] [Indexed: 11/29/2022]
Abstract
Organotin compounds (OTCs) are heavily employed by industry for a wide variety of applications, including the production of plastics and as biocides. Reports of environmental prevalence, differential toxicity between OTCs, and poorly characterized human exposure have fueled the demand for sensitive, selective speciation methods. The objective of this investigation was to develop and validate a rapid, sensitive, and selective analytical method for the simultaneous determination of a suite of organotin compounds, including butyl (mono-, di-, and tri-substituted) and phenyl (mono-, di-, and tri-substituted) species in human serum. The analytical method utilized ultra-performance liquid chromatography (UPLC) coupled with sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). The small (sub-2 µm) particle size of the UPLC column stationary phase and the sensitivity of the SF-ICP-MS enabled separation and sensitive determination of the analyte suite with a runtime of approximately 3 min. Validation activities included demonstration of method linearity over the concentration range of approximately 0.250-13.661 ng mL(-1), depending on the species; intraday precision of less than 21%, interday precision of less than 18%, intraday accuracy of -5.3% to 19%, and interday accuracy of -14% to 15% for all species; specificity, and matrix impact. In addition, sensitivity, and analyte stability under different storage scenarios were evaluated. Analyte stability was found to be limited for most species in freezer, refrigerator, and freeze-thaw conditions. The validated method was then applied for the determination of the OTCs in human serum samples from women participating in the Snart-Foraeldre/MiljØ (Soon-Parents/Environment) Study. The concentration of each OTC ranged from below the experimental limit of quantitation to 10.929 ng tin (Sn) mL(-1) serum. Speciation values were confirmed by a total Sn analysis.
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Affiliation(s)
- Keith E Levine
- RTI International, Research Triangle Park, NC, United States
| | - Daniel J Young
- RTI International, Research Triangle Park, NC, United States
| | - Scott E Afton
- RTI International, Research Triangle Park, NC, United States
| | | | - Amal S Essader
- RTI International, Research Triangle Park, NC, United States
| | - Frank X Weber
- RTI International, Research Triangle Park, NC, United States
| | | | - Kristina Thayer
- Division of National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Elizabeth E Hatch
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, United States
| | - Veronica G Robinson
- Division of National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
| | - Suramya Waidyanatha
- Division of National Toxicology Program, NIEHS, Research Triangle Park, NC, United States
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25
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Levine KE, Han L, Gwinn WM, Morgan DL, Ross GT, Essader AS, Fernando RA, Haines LG, Robinson VG. Development and Optimization of a Procedure for the Determination of Indium-Tin Oxide Particle Size and Concentration in Cellular Media. ANAL LETT 2014. [DOI: 10.1080/00032719.2013.878841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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26
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Collins BJ, Stout MD, Levine KE, Kissling GE, Melnick RL, Fennell TR, Walden R, Abdo K, Pritchard JB, Fernando RA, Burka LT, Hooth MJ. Exposure to hexavalent chromium resulted in significantly higher tissue chromium burden compared with trivalent chromium following similar oral doses to male F344/N rats and female B6C3F1 mice. Toxicol Sci 2010; 118:368-79. [PMID: 20843897 PMCID: PMC2984535 DOI: 10.1093/toxsci/kfq263] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 08/26/2010] [Indexed: 11/13/2022] Open
Abstract
In National Toxicology Program 2-year studies, hexavalent chromium [Cr(VI)] administered in drinking water was clearly carcinogenic in male and female rats and mice, resulting in small intestine epithelial neoplasms in mice at a dose equivalent to or within an order of magnitude of human doses that could result from consumption of chromium-contaminated drinking water, assuming that dose scales by body weight(3/4) (body weight raised to the 3/4 power). In contrast, exposure to trivalent chromium [Cr(III)] at much higher concentrations may have been carcinogenic in male rats but was not carcinogenic in mice or female rats. As part of these studies, total chromium was measured in tissues and excreta of additional groups of male rats and female mice. These data were used to infer the uptake and distribution of Cr(VI) because Cr(VI) is reduced to Cr(III) in vivo, and no methods are available to speciate tissue chromium. Comparable external doses resulted in much higher tissue chromium concentrations following exposure to Cr(VI) compared with Cr(III), indicating that a portion of the Cr(VI) escaped gastric reduction and was distributed systemically. Linear or supralinear dose responses of total chromium in tissues were observed following exposure to Cr(VI), indicating that these exposures did not saturate gastric reduction capacity. When Cr(VI) exposure was normalized to ingested dose, chromium concentrations in the liver and glandular stomach were higher in mice, whereas kidney concentrations were higher in rats. In vitro studies demonstrated that Cr(VI), but not Cr(III), is a substrate of the sodium/sulfate cotransporter, providing a partial explanation for the greater absorption of Cr(VI).
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Affiliation(s)
- Bradley J. Collins
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Matthew D. Stout
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Keith E. Levine
- Discovery and Analytical Sciences, RTI International, Research Triangle Park, North Carolina 27709
| | - Grace E. Kissling
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Ronald L. Melnick
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Timothy R. Fennell
- Discovery and Analytical Sciences, RTI International, Research Triangle Park, North Carolina 27709
| | - Ramsey Walden
- Laboratory of Pharmacology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Kamal Abdo
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - John B. Pritchard
- Laboratory of Pharmacology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Reshan A. Fernando
- Discovery and Analytical Sciences, RTI International, Research Triangle Park, North Carolina 27709
| | - Leo T. Burka
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Michelle J. Hooth
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
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Levine KE, Stout MD, Ross GT, Essader AS, Weber FX, Grohse PM, Fernando RA, Milstein LS, Hooth MJ, Collins BJ. Validation and application of a method for the determination of total chromium in rat tissues by inductively coupled plasma mass spectrometry. Arch Environ Contam Toxicol 2010; 58:883-891. [PMID: 19798462 DOI: 10.1007/s00244-009-9397-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Accepted: 09/08/2009] [Indexed: 05/26/2023]
Abstract
The validation of a method for the determination of chromium (Cr) in F-344/N rat tissues by inductively coupled plasma-mass spectrometry is described. Samples were analyzed after a rapid, open-vessel microwave digestion procedure. Performance of the method was evaluated using kidney tissue across a concentration range of 0.50-5.00 microg Cr/g tissue. Data for method linearity, accuracy, precision, digest stability, and storage stability are presented along with limits of detection and quantitation data. Data from a method cross-validation for B6C3F1 mouse kidney tissue are also presented. After validation, the method was applied to analyze samples collected in support of two chronic toxicity and carcinogenesis studies conducted by the National Toxicology Program.
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Affiliation(s)
- Keith E Levine
- RTI International, Research Triangle Park, NC 27709, USA.
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28
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Levine KE, Stout MD, Ross GT, Essader AS, Perlmutter JM, Grohse PM, Fernando RA, Lang M, Collins BJ. Validation of a Method for the Determination of Total Chromium in Rat Feces by Inductively Coupled Plasma Optical Emission Spectrometry. ANAL LETT 2009; 42:2729-2746. [PMID: 32494086 PMCID: PMC7269159 DOI: 10.1080/00032710902721931] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The validation of a method for the determination of total chromium in Fischer-344 rat feces by inductively coupled plasma optical emission spectrometry following a rapid, atmospheric-pressure microwave digestion is described. The performance of the method was evaluated over the concentration range of 5.00 to 200 μg Cr/g feces. Data for method linearity, accuracy, precision, digest stability, and storage stability are presented along with limit of detection and limit of quantitation data. Data from a cross-validation method for B6C3F1 mouse feces are also presented. Following validation, the method was applied to analyze samples collected in support of two chronic toxicological investigations.
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Affiliation(s)
- Keith E. Levine
- RTI International, Research Triangle Park, North Carolina, USA
| | - Matthew D. Stout
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Glenn T. Ross
- RTI International, Research Triangle Park, North Carolina, USA
| | - Amal S. Essader
- RTI International, Research Triangle Park, North Carolina, USA
| | | | - Peter M. Grohse
- RTI International, Research Triangle Park, North Carolina, USA
| | | | - Michelle Lang
- RTI International, Research Triangle Park, North Carolina, USA
| | - Bradley J. Collins
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
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29
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Lodge JW, Fletcher BL, Brown SS, Parham AJ, Fernando RA, Collins BJ. Determination of lovastatin hydroxy acid in female B6C3F1 mouse serum. J Anal Toxicol 2008; 32:248-52. [PMID: 18397577 DOI: 10.1093/jat/32.3.248] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A liquid chromatographic-mass spectrometricmethod for the determination of lovastatin hydroxy acid in female B6C3F(1) mouse serum was developed for use in supporting toxicokinetic studies of animals dosed with the cholesterol lowering agent lovastatin. The method does not require an extensive sample cleanup and shows good correlation between serum matrix standards and solvent standards. The method was validated and used to analyze serum samples from a preliminary dose level range-finding study. The method was validated for a concentration range of approximatel 1.0 to 100 ng/mL in serum, and linearity was verified to ~2000 ng/mL. The stability of sample extracts was determined under various storage conditions and the stability of serum samples stored frozen was determined over a period of seven weeks. During the course of analyzing the animal samples, the serum was monitored for the presence of lovastatin not hydrolyzed to the hydroxy acid, but no attempt was made to quantify lovastatin. No unhydrolyzed lovastatin was noted in any of the serum samples from animals dosed with lovastatin.
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Affiliation(s)
- Jon W Lodge
- RTI International, P.O. Box 12194, Research Triangle Park, North Carolina 27709-2194, USA
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30
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Levine KE, Essader AS, Weber FX, Perlmutter JM, Milstein LS, Fernando RA, Levine MA, Collins BJ, Adams JB, Grohse PM. Determination of iodine in low mass human hair samples by inductively coupled plasma mass spectrometry. Bull Environ Contam Toxicol 2007; 79:401-4. [PMID: 17721731 DOI: 10.1007/s00128-007-9264-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Accepted: 07/11/2007] [Indexed: 05/16/2023]
Affiliation(s)
- K E Levine
- RTI International, 3040 Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC 27709, USA.
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31
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Milstein LS, Essader A, Murrell C, Pellizzari ED, Fernando RA, Raymer JH, Akinbo O. Sample preparation, extraction efficiency, and determination of six arsenic species present in food composites. J Agric Food Chem 2003; 51:4180-4184. [PMID: 12848481 DOI: 10.1021/jf0210268] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Several sample preparation techniques were investigated to maximize the efficiency of arsenic species extraction from food composites. The optimized method includes lyophilization of food followed by prewashing with acetone and extraction by sonication with 50/50 methanol/water. Six arsenic species were separated and quantitated using an ammonium carbonate buffer system by ion exchange chromatography coupled to inductively coupled plasma mass spectrometry. The performance of the method for speciated arsenic components was evaluated using a matrix containing high fat food composite fortified with arsenic species. A certified reference material, dogfish muscle, was used to evaluate extraction methods for total arsenic content in food composites. More than 200 food composite samples were analyzed during an 18 month period, demonstrating the reliability of the analytical method over a long time period.
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Affiliation(s)
- Lisa S Milstein
- RTI International, 3040 Cornwallis Road, RTP, NC 27709-2194, USA.
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Milstein LS, Essader A, Pellizzari ED, Fernando RA, Raymer JH, Levine KE, Akinbo O. Development and application of a robust speciation method for determination of six arsenic compounds present in human urine. Environ Health Perspect 2003; 111:293-6. [PMID: 12611657 PMCID: PMC1241385 DOI: 10.1289/ehp.5525] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Six arsenic species [arsenate, arsenite, arsenocholine, arsenobetaine, monomethyl arsonic acid, and dimethyl arsinic acid] present in human urine were determined using ion-exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Baseline separation was achieved for all six species as well as for the internal standard (potassium hexahydroxy antimonate V) in a single chromatographic run of less than 30 min, using an ammonium carbonate buffer gradient (between 10 and 50 mM) at ambient temperature, in conjunction with cation- and anion-exchange columns in series. The performance of the method was evaluated with respect to linearity, precision, accuracy, and detection limits. This method was applied to determine the concentration of these six arsenic species in human urine samples (n = 251) collected from a population-based exposure assessment survey. Method precision was demonstrated by the analysis of duplicate samples that were prepared over a 2-year analysis period. Total arsenic was also determined for the urine samples using flow injection analysis coupled to ICP-MS. The summed concentration of the arsenic species was compared with the measured arsenic total to demonstrate mass balance.
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Affiliation(s)
- Lisa S Milstein
- Research Triangle Institute, Research Triangle Park, North Carolina 27709-2194, USA.
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Levine KE, Fernando RA, Lang M, Essader A, Wong BA. Development and Validation of a High- Throughput Method for the Determination of Titanium Dioxide in Rodent Lung and Lung-Associated Lymph Node Tissues. ANAL LETT 2003. [DOI: 10.1081/al-120018244] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Milstein LS, Essader A, Pellizzari ED, Fernando RA, Akinbo O. Selection of a suitable mobile phase for the speciation of four arsenic compounds in drinking water samples using ion-exchange chromatography coupled to inductively coupled plasma mass spectrometry. Environ Int 2002; 28:277-283. [PMID: 12220114 DOI: 10.1016/s0160-4120(02)00035-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The performance of two mobile phase buffers, phosphate and TRIS, were compared for the speciation of four arsenic species: arsenate (As(V)), arsenite (As(III)), mono methylarsonic acid (MMA), and dimethyl arsinic acid (DMA) in drinking water, using ion-exchange chromatography inductivelycoupled plasma mass spectrometry (IEC-ICP-MS). The mobile phase containing TRIS acetate buffer ("TRIS") demonstrated superior perfomance in baseline separation of all four arsenic species and the internal standard. It is also applicable to high-throughput sample analysis as it minimized the frequency required to clean the sampling interface due to salt build-up when compared to the phosphate mobile phase. The method was evaluated for its precision, accuracy, linearity and detection limits. The method was successfully applied for the analysis of drinking water samples.
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Affiliation(s)
- Lisa S Milstein
- Research Triangle Institute, Analytical and Chemical Sciences, RTP, NC 27709-2194, USA.
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Levine KE, Fernando RA, Ross GT, Lang M, Morgan DL, Collins BJ. DEVELOPMENT AND VALIDATION OF A METHOD FOR THE DETERMINATION OF MERCURY IN SMALL RAT BRAIN TISSUE SAMPLES BY COLD VAPOR ATOMIC FLUORESCENCE SPECTROMETRY. ANAL LETT 2002. [DOI: 10.1081/al-120006726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Levine KE, Fernando RA, Lang M, Essader A, Handy RW, Collins BJ. Development of a method for the determination of ultra-trace level mercury in adipose tissue by cold vapour atomic fluorescence spectrometry. J Autom Methods Manag Chem 2000; 22:103-108. [PMID: 18924864 PMCID: PMC2548265 DOI: 10.1155/s1463924600000146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A method for the determination of total mercury in rat adipose tissue by cold vapour atomic fluorescence spectrometry (CVAFS) has been developed. Adipose samples were initially subjected to a lyophilization procedure in order to facilitate the homogenization and accurate weighing of small tissue aliquots (approximately 50 mg). A closed vessel microwave digestion procedure using a mixture of sulphuric and nitric acids was used to liberate mercury from the adipose matrix. All mercury species were quantitatively oxidized to Hg(II) by a potassium bromate/bromide oxidation, then reduced to Hg(0) vapour by stannous chloride prior to fluorescence detection. The CVAFS exhibited a linear range of 10 pg Hg/ml to 120 pg Hg/ml. The method detection limit in solution was 2 pg Hg/ml, or 1 ng Hg/g adipose tissue, based on a nominal 50 mg sample and a final volume of 25 ml. A reference material from the National Research Council of Canada (DOLT-2, trace metals in dogfish liver) was prepared in quadruplicate in order to assess the accuracy and precision of the method. Mercury in this material was recovered at 2.22 +/- 0.08 microg/g, which is 104% of the certified level (2.14 +/- 0.10 microg/g).
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Affiliation(s)
- K E Levine
- Research Triangle Institute, 3040 Cornwallis Road, P.O. Box 12194, Research Triangle Park, NC 27709-2194, USA
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Abstract
1. Blood lead levels were examined in 127 housepainters in North Carolina between April and September, 1993. Each participant filled out a questionnaire and gave a blood sample. The questionnaire covered the individual's work history, concentrating on paint-removal activities and personal protection, and also covered potential nonoccupational sources of lead exposure. Blood samples were analysed for lead content using atomic absorption spectroscopy. 2. The geometric mean blood lead level was 0.33 mumol L-1 (6.8 micrograms dL-1). No blood lead samples were found to exceed the occupational standard of 1.93 mumol L-1 (40 micrograms dL-1). The three highest samples had levels between 0.97 and 1.45 mumol L-1 (20 and 30 micrograms dL-1); this represented 2.4% of the study sample. 3. No statistical association was found between blood lead levels in these painters and their painting activities, including using dust masks for personal protection. 4. Current painting practices in this group of North Carolina painters do not appear to elevate blood lead levels above the occupational standard.
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Affiliation(s)
- F K Ennever
- Department of Public Health Sciences, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina 27157-1063, USA
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Patel M, Fernando RA. Speed of onset of sensory block for elective extradural caesarean section. Br J Anaesth 1994; 73:865-6. [PMID: 7880684 DOI: 10.1093/bja/73.6.865-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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Abstract
Forty obstetric patients were randomly allocated to receive either a midline or paramedian approach to the epidural space using loss of resistance to air. Tissue trauma was assessed by blinded observers, clinically by the presence of pain and radiologically using magnetic resonance imaging (MRI). Technical difficulties with imaging reduced those who were scanned to 10 in the paramedian group and 8 in the midline group. Lateralizing signs of tissue oedema were not related to the method of epidural cannulation. There was no significant difference in localized back pain between the two groups, and this was not related to MRI findings. Pain did not persist for more than 4 days.
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Affiliation(s)
- A Holdcroft
- Department of Anaesthetics, Royal Postgraduate Medical School, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
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