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Lisco G, Accardo G, Pupilli C, Malandrino P, De Geronimo V, Triggiani V. Perchlorates in the treatment of hyperthyroidism and thyrotoxicosis: a comprehensive review. Endocrine 2024; 85:1-10. [PMID: 38195966 PMCID: PMC11246303 DOI: 10.1007/s12020-023-03679-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 12/25/2023] [Indexed: 01/11/2024]
Abstract
INTRODUCTION Perchlorates are ionic inhibitors antagonizing iodine transport into thyrocytes, hampering thyroid hormone synthesis. Nevertheless, perchlorates are not considered as first-line treatment in hyperthyroidism and thyrotoxicosis as compared to other pharmacological and non-pharmacological interventions. AIM Reassessing the therapeutic role of perchlorates in hyperthyroidism and thyrotoxicosis throughout a systematic review of the Literature. METHODS Guidelines were searched and examined to summarize current recommendations on the use of perchlorates in the management of hyperthyroidism. Randomized and non-randomized clinical trials were also searched and reviewed to summarize the efficacy/effectiveness and safety of perchlorates in hyperthyroidisms and thyrotoxicosis. RESULTS The management of specific forms of hyperthyroidism was considered, including Graves' disease (GD) in non-pregnant adults, hyperthyroidisms in pregnancy, iodine media contrast-induced hyperthyroidism, amiodarone-induced hyperthyroidisms, and thyroid storm. Most of the reported studies had remarkable limitations in terms of study design (non-controlled trials, lack of blinding), low number of participants, and the lack of clinically relevant endpoints, such as cardiovascular events, cardiovascular mortality, and teratogenicity. Overall, perchlorates could be considered a second-line treatment after thionamides, radioiodine, and total thyroidectomy in both GD and hyperthyroidisms in pregnancy. The therapeutic potential of perchlorates alone or in combination with other agents could be considered a second-line treatment of iodine-related hyperthyroidisms and thyroid storm. CONCLUSION Despite the low level of evidence, perchlorates could be considered in such specific forms of thyroid disorders, including iodine-induced hyperthyroidism and thyroid storm.
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Affiliation(s)
- Giuseppe Lisco
- Interdisciplinary Department of Medicine, School of Medicine, University of Bari "Aldo Moro", Bari, 70124, Italy.
| | - Giacomo Accardo
- Dipartmento di Scienze Mediche, Chirurgiche, Neurologiche, Metabolismo ed Invecchiamento, Università degli Studi della Campania "L. Vanvitelli", Napoli, 80133, Italia
| | - Cinzia Pupilli
- SOSD Endocrinologia - Azienda USL Toscana Centro, Firenze, 50122, Italia
| | - Pasqualino Malandrino
- Endocrinologia, Dipartimento di Medicina Clinica e Sperimentale, Arnas Garibaldi, Università di Catania", Catania, Italy
| | | | - Vincenzo Triggiani
- Interdisciplinary Department of Medicine, School of Medicine, University of Bari "Aldo Moro", Bari, 70124, Italy.
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Tseng CH, Tseng CL, Chen HS, Chen PL, Huang CJ. Clinical characteristics of neutropenic patients under antithyroid drug: Twelve-year experience in a medical center. J Chin Med Assoc 2023; 86:826-834. [PMID: 37466683 DOI: 10.1097/jcma.0000000000000966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND Thionamide-induced agranulocytosis (TiA) is a rare adverse event with a reported incidence of approximately 0.1% to 1.75%. Prompt recognition of TiA is critical to reduce the mortality rate. However, the differential diagnosis between cases of TiA and non-TiA neutropenia can be challenging due to the potential simultaneous involvement of other causes of neutropenia, such as concomitant chemotherapy, liver dysfunction, or infection. The aim of the present study was to investigate the possible factors associated with the development of TiA. METHODS This was a retrospective cohort study of patients treated with antithyroid drugs (ATDs) in Taipei Veterans General Hospital, Taipei, Taiwan, from 2006 to 2018. Patients who developed a neutropenic event during treatment with ATDs were identified from their medical records. The diagnosis of TiA was based on the following: (1) development of neutropenia during treatment or within 7 days after previous exposure to the same ATDs; (2) complete resolution of neutropenia within 1 month after discontinuation of the culprit drug with an absolute neutrophil count (ANC) >1500/μL; and (3) exclusion of other causes of neutropenia. The incidence and risk factors of TiA were analyzed and compared with those of non-TiA neutropenia. RESULTS Among 6644 patients treated with ATDs, 66 (mean age: 53 ± 15 years; 16.2% men) developed a neutropenic event and 20 were diagnosed with TiA (incidence: 0.3%). In the univariate analysis, compared with non-TiA neutropenia, TiA was associated with a lower Charlson Comorbidity Index, shorter treatment duration, lower cumulative ATD dosage, higher ATD dosage, higher ANC, and higher levels of free T4 at the time of the neutropenic event. In the multivariate logistic regression analysis, after adjusting for age, gender and the time to neutropenia, the cumulative ATD dose to neutropenia and ATD dosage at the time of the neutropenic event, Charlson Comorbidity Index, free T4 levels (odds ratio [OR], 4.44; 95% CI, 1.48-13.25), and ANC (OR, 1.00; 95% CI, 1.00-1.01) remained independently associated with TiA. CONCLUSION Patients with TiA were more likely to have higher levels of free T4 and ANC at the time of the neutropenic event vs those with non-TiA neutropenia.
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Affiliation(s)
- Chih-Hsueh Tseng
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Chi-Lung Tseng
- Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
- Division of Gastroenterology, Department of Internal Medicine, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan, Taiwan, ROC
| | - Harn-Shen Chen
- Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Pei-Lung Chen
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan, ROC
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University, Taipei, Taiwan, ROC
- Academia Sinica and National Taiwan University, Taipei, Taiwan, ROC
- Division of Endocrinology and Metabolism, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Chun-Jui Huang
- Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- Institute of Public Health, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
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Bermejo-Haro MY, Camacho-Pacheco RT, Brito-Pérez Y, Mancilla-Herrera I. The hormonal physiology of immune components in breast milk and their impact on the infant immune response. Mol Cell Endocrinol 2023:111956. [PMID: 37236499 DOI: 10.1016/j.mce.2023.111956] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023]
Abstract
During pregnancy, the maternal body undergoes a considerable transformation regarding the anatomy, metabolism, and immune profile that, after delivery, allows for protection and nourishment of the offspring via lactation. Pregnancy hormones are responsible for the development and functionality of the mammary gland for breast milk production, but little is known about how hormones control its immune properties. Breast milk composition is highly dynamic, adapting to the nutritional and immunological needs that the infant requires in the first months of life and is responsible for the main immune modeling of breastfed newborns. Therefore, alterations in the mechanisms that control the endocrinology of mammary gland adaptation for lactation could disturb the properties of breast milk that prepare the neonatal immune system to respond to the first immunologic challenges. In modern life, humans are chronically exposed to endocrine disruptors (EDs), which alter the endocrine physiology of mammals, affecting the composition of breast milk and hence the neonatal immune response. In this review, we provide a landscape of the possible role of hormones in the control of passive immunity transferred by breast milk and the possible effect of maternal exposure to EDs on lactation, as well as their impacts on the development of neonatal immunity.
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Affiliation(s)
- Mextli Y Bermejo-Haro
- Infectology and Immunology Department, National Institute of Perinatology (INPer), Mexico City, Mexico; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico; Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, 11340, Mexico
| | - Rodrigo T Camacho-Pacheco
- Infectology and Immunology Department, National Institute of Perinatology (INPer), Mexico City, Mexico; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico; Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, 11340, Mexico
| | - Yesenia Brito-Pérez
- Infectology and Immunology Department, National Institute of Perinatology (INPer), Mexico City, Mexico; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico; Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, 11340, Mexico
| | - Ismael Mancilla-Herrera
- Infectology and Immunology Department, National Institute of Perinatology (INPer), Mexico City, Mexico.
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Li W, Wu H, Xu X, Zhang Y. Environmental exposure to perchlorate, nitrate, and thiocyanate in relation to chronic kidney disease in the general US population, NHANES 2005-2016. Chin Med J (Engl) 2023:00029330-990000000-00571. [PMID: 37154820 DOI: 10.1097/cm9.0000000000002586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Indexed: 05/10/2023] Open
Abstract
BACKGROUND Few studies have explored the impact of perchlorate, nitrate, and thiocyanate (PNT) on kidney function. This study aimed to evaluate the association of urinary levels of PNT with renal function as well as the prevalence of chronic kidney disease (CKD) among the general population in the United States. METHODS This analysis included data from 13,373 adults (≥20 years) from the National Health and Nutrition Examination Survey 2005 to 2016. We used multivariable linear and logistic regression, to explore the associations of urinary PNT with kidney function. Restricted cubic splines were used to assess the potentially non-linear relationships between PNT exposure and outcomes. RESULTS After traditional creatinine adjustment, perchlorate (P-traditional) was positively associated with estimated glomerular filtration rate (eGFR) (adjusted β: 2.75; 95% confidence interval [CI]: 2.25 to 3.26; P < 0.001), and negatively associated with urinary albumin-to-creatinine ratio (ACR) (adjusted β: -0.05; 95% CI: -0.07 to -0.02; P = 0.001) in adjusted models. After both traditional and covariate-adjusted creatinine adjustment, urinary nitrate and thiocyanate were positively associated with eGFR (all P values <0.05), and negatively associated with ACR (all P values <0.05); higher nitrate or thiocyanate was associated with a lower risk of CKD (all P values <0.001). Moreover, there were L-shaped non-linear associations between nitrate, thiocyanate, and outcomes. In the adjusted models, for quartiles of PNT, statistically significant dose-response associations were observed in most relationships. Most results were consistent in the stratified and sensitivity analyses. CONCLUSIONS Exposures to PNT might be associated with kidney function, indicating a potential beneficial effect of environmental PNT exposure (especially nitrate and thiocyanate) on the human kidney.
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Affiliation(s)
- Wei Li
- Department of Plastic and Burns Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Hong Wu
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, Sichuan 610041, China
| | - Xuewen Xu
- Department of Plastic and Burns Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yange Zhang
- Department of Plastic and Burns Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
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Ruslan A, Okosieme OE. Non-thionamide antithyroid drug options in Graves' hyperthyroidism. Expert Rev Endocrinol Metab 2023; 18:67-79. [PMID: 36740774 DOI: 10.1080/17446651.2023.2167709] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/09/2023] [Indexed: 01/13/2023]
Abstract
INTRODUCTION The thionamide anti-thyroid drugs namely carbimazole, methimazole, and propylthiouracil, have been the predominant therapy modality for Graves' hyperthyroidism for over 60 years. Although these agents have proven efficacy and favorable side-effect profiles, non-thionamide alternatives are occasionally indicated in patients who are intolerant or unresponsive to thionamides alone. This review examines the available non-thionamide drug options for the control of Graves' hyperthyroidism and summarizes their clinical utility, efficacy, and limitations. AREAS COVERED We reviewed existing literature on mechanisms, therapeutic utility, and side-effect profiles of non-thionamide anti-thyroid drugs. Established non-thionamide agents act on various phases of the synthesis, release, and metabolism of thyroid hormones and comprise historical agents such as iodine compounds and potassium perchlorate as well as drug repurposing candidates like lithium, glucocorticoids, beta-blockers, and cholestyramine. Novel experimental agents in development target key players in Graves' disease pathogenesis including B-cell depletors (Rituximab), CD40 blockers (Iscalimab), TSH-receptor antagonists, blocking antibodies, and immune-modifying peptides. EXPERT OPINION Non-thionamide anti-thyroid drugs are useful alternatives in Graves' hyperthyroidism and more clinical trials are needed to establish their safety and long-term efficacy in hyperthyroidism control. Ultimately, the promise for a cure will lie in novel approaches that target the well-established immunopathogenesis of Graves' disease.
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Affiliation(s)
- Aliya Ruslan
- Endocrine and Diabetes Department, Prince Charles Hospital, Cwm Taf University Health Board, Merthyr Tydfil, CF47 9DT, UK
| | - Onyebuchi E Okosieme
- Endocrine and Diabetes Department, Prince Charles Hospital, Cwm Taf University Health Board, Merthyr Tydfil, CF47 9DT, UK
- Thyroid Research Group, Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, UK
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Błażewicz A, Niziński P, Dolliver I, Dolliver W, Makarewicz A, Skórzyńska-Dziduszko K. Alterations of urinary perchlorate levels in euthyroid postpubertal children with autism spectrum disorder. J Trace Elem Med Biol 2021; 68:126800. [PMID: 34102587 DOI: 10.1016/j.jtemb.2021.126800] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Perchlorates ClO4(-) are known environmental and food contaminants that act as inhibitors of iodine uptake by the thyroid gland; however, information concerning their possible association with the development of autism spectrum disorder (ASD) is still missing. The current study is first presenting the alterations in perchlorate urine levels in euthyroid children with ASD. OBJECTIVES To examine urinary perchlorates and iodides in euthyroid children diagnosed with ASD, compared to age-, and BMI-matched neurotypical controls, and to verify the association between these two ions in ASD. METHODS Ions were determined in 24 h urine samples determined by ion chromatography-conductivity cell detection (IC-CD) and ion chromatography-pulsed amperometric detection (IC-PAD) techniques, respectively, in a total of 130 postpubertal euthyroid children with normal BMI (the mean age 14.46 years, SD = 1.32; the mean BMI 20.6, SD = 1.37), divided into age- and BMI-matched groups of ASD patients and neurotypical, healthy children (control). RESULTS The ASD group presented with significantly higher perchlorate urine levels than the controls (median = 1.05 μg/L, interquartile range(IQR) = 1.5 versus median = 0.09 μg/L, IQR = 0.097, respectively), as well as lower iodide urine levels (median = 100.2 μg/L, IQR = 37 versus median = 156.95 μg/L, IQR = 26.11, respectively). The ASD group presented significantly lower TSH and higher free thyroid hormone (fT4, fT3) levels than the controls. In regression analyses, perchlorate urine levels showed significant positive relationships with normal BMI values and serum TSH, and inverse relationships with serum fT4. Urinary iodide levels showed significant inverse relationships with BMI values. The absence of ASD was associated with decreased odds of perchlorate urine levels (OR = 0.012, 95 % confidence interval [CI] 0.0002-0.76), and increased odds of iodide urine levels (OR = 1.15, 95 %CI 1.05-1.27). CONCLUSIONS ASD may have an independent and significant impact on perchlorate as well as iodide levels in urine of euthyroid lean postpubertal children. Perchlorate levels do not appear to be directly associated with iodide levels in euthyroid children.
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Affiliation(s)
- Anna Błażewicz
- Department of Analytical Chemistry, Medical University of Lublin, 20-093, Lublin, Poland.
| | - Przemysław Niziński
- Department of Analytical Chemistry, Medical University of Lublin, 20-093, Lublin, Poland
| | - Iwona Dolliver
- Department of Analytical Chemistry, Medical University of Lublin, 20-093, Lublin, Poland
| | - Wojciech Dolliver
- The Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Agata Makarewicz
- Department of Psychiatry, Psychotherapy and Early Intervention, Medical University of Lublin, 20-439, Lublin, Poland
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Studies on perchlorate levels in powdered infant formulas available on the Polish market. CURRENT ISSUES IN PHARMACY AND MEDICAL SCIENCES 2021. [DOI: 10.2478/cipms-2021-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract
Perchlorate has been acknowledged as a health threat due to its ability to interfere with iodine uptake by the thyroid gland. Infants and developing newborns have been considered as the most vulnerable groups to the perchlorate toxicity. A crucial source of perchlorate ingestion are powdered infant formulas. This study was designed to measure perchlorate content in thirty-one powdered infant formulas available on the Polish market. A rapid and sensitive ion chromatography method – conductivity cell detection – was applied to determine
ClO
4
−
{\rm{ClO}}_4^ -
content. Limit of detection (0.150 µg/L) and limit of quantification (0.450 µg/L) were assessed. Collected samples were classified by the age of consumers: first stage, until the baby is six months old and follow-on formula for older children. Geometric mean of perchlorate concentration of 1.041 µg/L and 0.857 µg/L in the groups of the first stage and follow-on formulas were calculated, respectively. A health risk assessment revealed that the Tolerable Daily Intake (TDI) for perchlorate (0.3 µg/kg body weight/day) was exceeded only in a few milk samples. The findings suggest that perchlorate contamination of powdered infant formulas may not to be an immediate health issue, yet testing for
ClO
4
−
{\rm{ClO}}_4^ -
should continuously be conducted. To the best of our knowledge, this is the first study concerning perchlorate content in infant formulas in Poland.
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Niziński P, Błażewicz A, Kończyk J, Michalski R. Perchlorate - properties, toxicity and human health effects: an updated review. REVIEWS ON ENVIRONMENTAL HEALTH 2021; 36:199-222. [PMID: 32887207 DOI: 10.1515/reveh-2020-0006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 07/28/2020] [Indexed: 06/11/2023]
Abstract
Interest in perchlorate as environmental pollutant has increased since 1997, when high concentrations have been found in the waters of the Colorado River, USA. Perchlorate is very persistent in nature and it is slowly degraded. Although harmful effects of large doses of perchlorate on thyroid function have been proven, the environmental effects are still unclear. The primary objective of the present review is to collect prevailing data of perchlorate exposure and to discuss its impact on human health. The results show that more than 50% of reviewed works found significant associations of perchlorate exposure and human health. This review consists of the following sections: general information of perchlorate sources, its properties and determination methods, role and sources in human body including food and water intake, overview of the scientific literature on the research on the effect of perchlorate on human health from 2010 to 2020. Finally, conclusions and recommendations on future perchlorate studies concerning human exposure are presented.
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Affiliation(s)
- Przemysław Niziński
- Chair of Chemistry, Department of Analytical Chemistry, Medical University of Lublin, Lublin, Poland
| | - Anna Błażewicz
- Chair of Chemistry, Department of Analytical Chemistry, Medical University of Lublin, Lublin, Poland
| | - Joanna Kończyk
- Institute of Chemistry, Health and Food Sciences, Faculty of Mathematics and Natural Sciences, Jan Dlugosz University in Czestochowa, Czestochowa, Poland
| | - Rajmund Michalski
- Institute of Chemistry, Health and Food Sciences, Faculty of Mathematics and Natural Sciences, Jan Dlugosz University in Czestochowa, Czestochowa, Poland
- Institute of Environmental Engineering, Polish Academy of Sciences, Zabrze, Poland
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Eder S, Hermann C, Lamkowski A, Kinoshita M, Yamamoto T, Abend M, Shinomiya N, Port M, Rump A. A comparison of thyroidal protection by stable iodine or perchlorate in the case of acute or prolonged radioiodine exposure. Arch Toxicol 2020; 94:3231-3247. [PMID: 32656655 PMCID: PMC7415763 DOI: 10.1007/s00204-020-02809-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/15/2020] [Indexed: 12/14/2022]
Abstract
In the case of a nuclear power plant accident, repetitive/prolonged radioiodine release may occur. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses of non-radioactive iodine may protect the thyroid by inhibiting radioiodine uptake into the gland (iodine blockade). Protection is based on a competition at the active carrier site in the cellular membrane and the Wolff-Chaikoff effect, the latter being, however, only transient (24-48 h). Perchlorate may alternatively provide protection by a carrier competition mechanism only. Perchlorate has, however, a stronger affinity to the carrier than iodide. Based on an established biokinetic-dosimetric model developed to study iodine blockade, and after its extension to describe perchlorate pharmacokinetics and the inhibition of iodine transport through the carrier, we computed the protective efficacies that can be achieved by stable iodine or perchlorate in the case of an acute or prolonged radioiodine exposure. In the case of acute radioiodine exposure, perchlorate is less potent than stable iodine considering its ED50. A dose of 100 mg stable iodine has roughly the same protective efficacy as 1000 mg perchlorate. For prolonged exposures, single doses of protective agents, whether stable iodine or perchlorate, offer substantially lower protection than after acute radioiodine exposure, and thus repetitive administrations seem necessary. In case of prolonged exposure, the higher affinity of perchlorate for the carrier in combination with the fading Wolff-Chaikoff effect of iodine confers perchlorate a higher protective efficacy compared to stable iodine. Taking into account the frequency and seriousness of adverse effects, iodine and perchlorate at equieffective dosages seem to be alternatives in case of short-term acute radioiodine exposure, whereas preference should be given to perchlorate in view of its higher protective efficacy in the case of longer lasting radioiodine exposures.
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Affiliation(s)
- Stefan Eder
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany
| | - Cornelius Hermann
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany
| | - Andreas Lamkowski
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany
| | - Manabu Kinoshita
- Japan Self Defense Forces National Defense Medical College Research Institute, Tokorozawa, Japan
| | - Tetsuo Yamamoto
- Japan Ground Self Defense Forces Military Medicine Research Unit and Ministry of Defense Clinic, Tokyo, Japan
| | - Michael Abend
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany
| | - Nariyoshi Shinomiya
- Japan Self Defense Forces National Defense Medical College Research Institute, Tokorozawa, Japan
| | - Matthias Port
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany
| | - Alexis Rump
- Bundeswehr Institute of Radiobiology, Neuherberg Str. 11, 80937, Munich, Germany.
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Lisco G, De Tullio A, Giagulli VA, De Pergola G, Triggiani V. Interference on Iodine Uptake and Human Thyroid Function by Perchlorate-Contaminated Water and Food. Nutrients 2020; 12:E1669. [PMID: 32512711 PMCID: PMC7352877 DOI: 10.3390/nu12061669] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue. METHODS Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences. RESULTS Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels. DISCUSSION AND CONCLUSION The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.
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Affiliation(s)
- Giuseppe Lisco
- ASL Brindisi, Unit of Endocrinology, Metabolism & Clinical Nutrition, Hospital “A. Perrino”, Strada per Mesagne 7, 72100 Brindisi, Puglia, Italy;
| | - Anna De Tullio
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
| | - Vito Angelo Giagulli
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
- Clinic of Endocrinology and Metabolic Disease, Conversano Hospital, Via Edmondo de Amicis 36, 70014 Conversano, Bari, Puglia, Italy
| | - Giovanni De Pergola
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine and Clinical Oncology, University of Bari Aldo Moro, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy;
| | - Vincenzo Triggiani
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
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Possible Effects of Perchlorate Contamination of Drinking Water on Thyroid Health. J Thyroid Res 2020; 2020:5208657. [PMID: 32454966 PMCID: PMC7243002 DOI: 10.1155/2020/5208657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 03/14/2020] [Accepted: 04/16/2020] [Indexed: 11/18/2022] Open
Abstract
Background Perchlorate is an anion that occurs as a contaminant in groundwater. It originates from the improper disposal of ammonium perchlorate, a component of rocket fuel. The objective of this study was to explore whether the exposure to perchlorate in drinking water had an impact on the thyroid function of the population residing near an ammonium perchlorate plant in Kerala. Methodology. Using an ecological study design, we compared the serum levels of thyroid-stimulating hormone, thyroxine, and thyroid peroxidase antibodies among a representative sample of 289 study subjects from the area surrounding the ammonium perchlorate enrichment plant to 281 study subjects in a control area. Results The perchlorate concentration in the groundwater varied from 1600 ppb to 57,000 ppb in the 10 samples from the contaminated area and was below 24 ppb in all locations in the control area. No significant differences were found in the mean serum TSH concentration and mean T4 levels between the subjects from the contaminated area and the control area. On regression analysis, perchlorate contamination was not found to be a significant predictor of TSH. Conclusion This study did not find any significant association between perchlorate in drinking water and changes in thyroid hormone levels. Our findings indicate the need for further investigation of this hypothesis using urinary perchlorate as a measure of individual exposure.
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Wang Z, Sparling M, Wang KC, Arbuckle TE, Fraser W. Perchlorate in human milk samples from the maternal-infant research on environmental chemicals study (MIREC). Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2019; 36:1837-1846. [DOI: 10.1080/19440049.2019.1668968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Zhongwen Wang
- Bureau of Chemical Safety, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Melissa Sparling
- Bureau of Chemical Safety, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Kuan Chiao Wang
- Bureau of Food Surveillance and Science Integration, Food Directorate, Health Product and Food Branch, Health Canada, Ottawa, ON, Canada
| | - Tye E. Arbuckle
- Population Studies Division, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON, Canada
| | - William Fraser
- Departement D'obstetrique et gynecologie, Centre de recherche du Centre hospitalier universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Sainte Justine University Hospital Research Center, University of Montreal, Montreal, QC, Canada
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13
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Kurek J, Kwaśniewska-Sip P, Myszkowski K, Cofta G, Barczyński P, Murias M, Kurczab R, Śliwa P, Przybylski P. Antifungal, anticancer, and docking studies of colchiceine complexes with monovalent metal cation salts. Chem Biol Drug Des 2019; 94:1930-1943. [PMID: 31260187 DOI: 10.1111/cbdd.13583] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 05/29/2019] [Accepted: 06/17/2019] [Indexed: 01/22/2023]
Abstract
Complexes of colchiceine with monovalent cation perchlorates and iodides have been obtained and characterized by spectroscopic methods. DFT and spectroscopic studies reveal that the dihedral angle ω1-1a-12-12a , crucial for colchicine biological mechanism of action, that is, binding to tubulins depends on the diameter of the complexed metal cation. Biological tests indicated no antifungal properties of colchicine (it was active only toward A.pullulans), in contrast to its derivative-(colchiceine). Complexation of colchiceine with metal cations improved significantly the antifungal potency, even below MIC <1 μg/ml. The colchiceine complexes were more potent than colchiceine, and some of them were even more potent than the fungicidal standard IPBC. The highest potency of colchiceine complexes was noted against A. pullulans (MIC = 0.5 μg/ml). In contrast to the findings concerning antifungal potency, the anticancer studies showed complexes of colchicine more active (~IC50 = 2 nM) than those of colchiceine (~IC50 = 6 μM). MDA-MB-231 breast cancer cell lines and human lung fibroblasts CCD39Lu were also tested.
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Affiliation(s)
- Joanna Kurek
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
| | - Patrycja Kwaśniewska-Sip
- Wood Technology Institute, Environmental Protection and Wood Chemistry Department, Poznan, Poland
| | | | - Grzegorz Cofta
- Institute of Chemical Wood Technology, University of Life Science, Poznań, Poland
| | - Piotr Barczyński
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
| | - Marek Murias
- Department of Toxicology, Poznan University of Medical Sciences, Poznań, Poland
| | - Rafał Kurczab
- Department of Medicinal Chemistry, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Paweł Śliwa
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, Kraków, Poland
| | - Piotr Przybylski
- Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
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Serrano-Nascimento C, Calil-Silveira J, Dalbosco R, Zorn TT, Nunes MT. Evaluation of hypothalamus-pituitary-thyroid axis function by chronic perchlorate exposure in male rats. ENVIRONMENTAL TOXICOLOGY 2018; 33:209-219. [PMID: 29139221 DOI: 10.1002/tox.22509] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 10/24/2017] [Accepted: 10/25/2017] [Indexed: 06/07/2023]
Abstract
Perchlorate is a widespread endocrine disruptor that was previously correlated with increased serum TSH levels and decreased thyroid hormones production both in animals and humans. Even so, the regulation of gene/protein expression in the hypothalamus, pituitary and thyroid by chronic perchlorate exposure was not completely elucidated. Therefore, this study aimed to investigate the underlying mechanisms involved in the disruption of hypothalamus-pituitary-thyroid axis by chronic perchlorate exposure. Male Wistar rats were treated or not with NaClO4 in the drinking water (35 mg/Kg/day) for 60 days. Thereafter, hormone/cytokines serum levels were measured through multiplex assays; genes/proteins expression were investigated by qPCR/Western Blotting and thyroid morphology was evaluated through histological analysis. Serum TSH levels were increased and serum T4 /T3 levels were decreased in perchlorate-treated animals. This treatment also altered the thyrotropin-releasing hormone mRNA/protein content in the hypothalamus. Additionally, the expression of both subunits of TSH were increased in the pituitary of perchlorate-treated rats, which also presented significant alterations in the thyroid morphology/gene expression. Furthermore, perchlorate exposure reduced liver Dio1 mRNA expression and increased the content of pro-inflammatory cytokines in the thyroid and the serum. In conclusion, our study adds novel findings about the perchlorate-induced disruption of the hypothalamus-pituitary-thyroid axis gene/protein expression in male rats. The data presented herein also suggest that perchlorate induces thyroid and systemic inflammation through the increased production of cytokines. Taken together, our results suggest that perchlorate contamination should be monitored, especially in the individuals most susceptible to the deleterious effects of reduced levels of thyroid hormones.
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Affiliation(s)
| | - Jamile Calil-Silveira
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | - Rafael Dalbosco
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | - Telma Tenorio Zorn
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | - Maria Tereza Nunes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Brazil
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15
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Zahran EM, Fatila EM, Chen CH, Flood AH, Bachas LG. Cyanostar: C–H Hydrogen Bonding Neutral Carrier Scaffold for Anion-Selective Sensors. Anal Chem 2018; 90:1925-1933. [DOI: 10.1021/acs.analchem.7b04008] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Elsayed M. Zahran
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33126, United States
- Applied
Organic Chemistry Department, National Research Centre, Cairo, 12622, Egypt
| | - Elisabeth M. Fatila
- Department
of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Chun-Hsing Chen
- Department
of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Amar H. Flood
- Department
of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Leonidas G. Bachas
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33126, United States
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16
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Wunderlich G, Wendisch M, Aurich D, Runge R, Freudenberg R, Kotzerke J. Preincubation with Sn-complexes causes intensive intracellular retention of 99mTc in thyroid cells in vitro. Nuklearmedizin 2018; 51:179-85. [DOI: 10.3413/nukmed-0450-11-12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 04/02/2012] [Indexed: 11/20/2022]
Abstract
SummaryTechnetium radiopharmaceuticals are well established in nuclear medicine. Besides its well-known gamma radiation, 99mTc emits an average of five Auger and internal conversion electrons per decay. The biological toxicity of these low-energy, high-LET (linear energy transfer) emissions is a controversial subject. One aim of this study was to estimate in a cell model how much 99mTc can be present in exposed cells and which radiobiological effects could be estimated in 99mTc-overloaded cells. Methods: Sodium iodine symporter (NIS)- positive thyroid cells were used. 99mTc-uptake studies were performed after preincubation with a non-radioactive (cold) stannous pyro - phosphate kit solution or as a standard 99mTc pyrophosphate kit preparation or with pure pertechnetate solution. Survival curves were analyzed from colony-forming assays. Results: Preincubation with stannous complexes causes irreversible intracellular radioactivity retention of 99mTc and is followed by further pertechnetate influx to an unexpectedly high 99mTc level. The uptake of 99mTc pertechnetate in NIS-positive cells can be modified using stannous pyrophosphate from 3–5% to >80%. The maximum possible cellular uptake of 99mTc was 90 Bq/cell. Compared with nearly pure extracellular irradiation from routine 99mTc complexes, cell survival was reduced by 3–4 orders of magnitude after preincubation with stannous pyrophosphate. Conclusions: Intra cellular 99mTc retention is related to reduced survival, which is most likely mediated by the emission of low-energy electrons. Our findings show that the described experiments constitute a simple and useful in vitro model for radiobiological investigations in a cell model.
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Affiliation(s)
- G Wunderlich
- Klinik und Poliklinik für Nuklearmedizin, Universitätsklinikum Carl Gustav Carus, Technische Universität, 01307 Dresden, Fetscherstr. 74, Germany.
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17
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Suwansaksri N, Preechasuk L, Kunavisarut T. Nonthionamide Drugs for the Treatment of Hyperthyroidism: From Present to Future. Int J Endocrinol 2018; 2018:5794054. [PMID: 29849619 PMCID: PMC5937426 DOI: 10.1155/2018/5794054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 03/11/2018] [Indexed: 12/20/2022] Open
Abstract
Hyperthyroidism is a common endocrine disease. Although thionamide antithyroid drugs are the cornerstone of hyperthyroidism treatment, some patients cannot tolerate this drug class because of its serious side effects including agranulocytosis, hepatotoxicity, and vasculitis. Therefore, nonthionamide antithyroid drugs (NTADs) still have an important role in controlling hyperthyroidism in clinical practice. Furthermore, some situations such as thyroid storm or preoperative preparation require a rapid decrease in thyroid hormone by combination treatment with multiple classes of antithyroid drugs. NTADs include iodine-containing compounds, lithium carbonate, perchlorate, glucocorticoid, and cholestyramine. In this narrative review, we summarize the mechanisms of action, indications, dosages, and side effects of currently used NTADs for the treatment of hyperthyroidism. In addition, we also describe the state-of-the-art in future drugs under development including rituximab, small-molecule ligands (SMLs), and monoclonal antibodies with a thyroid-stimulating hormone receptor (TSHR) antagonist effect.
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Affiliation(s)
| | - Lukana Preechasuk
- Siriraj Diabetes Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Tada Kunavisarut
- Division of Endocrine and Metabolism, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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18
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Rong Y, Kolodziej A, Madrid E, Carta M, Malpass-Evans R, McKeown NB, Marken F. Polymers of intrinsic microporosity in electrochemistry: Anion uptake and transport effects in thin film electrodes and in free-standing ionic diode membranes. J Electroanal Chem (Lausanne) 2016. [DOI: 10.1016/j.jelechem.2015.11.038] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Okosieme OE, Lazarus JH. Current trends in antithyroid drug treatment of Graves' disease. Expert Opin Pharmacother 2016; 17:2005-17. [PMID: 27615550 DOI: 10.1080/14656566.2016.1232388] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
INTRODUCTION Graves' hyperthyroidism is associated with significant morbidity and mortality risk. The thionamides, methimazole, its pro-drug derivative carbimazole, and propylthiouracil, remain a cornerstone of management. Yet despite decades of use, optimal strategies for maximising treatment response and curtailing adverse effect risk remains uncertain. AREAS COVERED We reviewed the current literature on the evidence based medical management of Graves' disease. Specifically, we evaluated current approaches to the use of thionamides, adjunctive therapies, and potential novel agents for controlling Graves' hyperthyroidism. EXPERT OPINION Primary medical therapy is successful in less than 50% of cases and so careful selection of patients for medical treatment based on a combination of pathological and pragmatic considerations is essential. Carbimazole or methimazole is the treatment of choice in the non-pregnant population driven by its more favourable pharmacokinetic and adverse effect profile over propylthiouracil. In pregnancy the choice of treatment is less straightforward and an approach that minimises undue fetal exposure to all thionamides should be adopted. Additional data is needed on the value of adjunctive therapies including potassium perchlorate, iodides, glucocorticoids, lithium, and cholestyramine. Novel agents directed against pathogenetic targets including TSH receptor blocking monoclonal antibodies and small molecule antagonists may hold promise for the future.
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Affiliation(s)
- Onyebuchi E Okosieme
- a Thyroid Research Group, Institute of Molecular and Experimental Medicine , School of Medicine, Cardiff University , Cardiff , UK.,b Endocrine and Diabetes Department , Prince Charles Hospital, Cwm Taf University Health Board , Merthyr Tydfil , UK
| | - John H Lazarus
- a Thyroid Research Group, Institute of Molecular and Experimental Medicine , School of Medicine, Cardiff University , Cardiff , UK
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20
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York RG, Funk KA, Girard MF, Mattie D, Strawson JE. Oral (Drinking Water) Developmental Toxicity Study of Ammonium Perchlorate in Sprague-Dawley Rats. Int J Toxicol 2016; 22:453-64. [PMID: 14680992 DOI: 10.1177/109158180302200606] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A developmental toxicity study was conducted with ammonium perchlorate (AP) in the drinking water at doses of 0.0, 0.01, 0.1, 1.0, and 30.0 mg/kg-day beginning 14 days before cohabitation and continuing through sacrifice. Twenty-four rats/group were cesarean-sectioned on day of gestation (DG) 21 and fetuses examined for visceral and skeletal alterations. An additional 16 litters/group were sacrificed on DG 21 for maternal and fetal serum TSH, T3, and T4 (thyroid-stimulating hormone, triiodothyronine, and thyroxine) levels and thyroid histopathology. Clinical and necropsy observations, body weights, feed and water consumption, and cesarean-sectioning parameters were comparable among the groups with only delays in ossification observed in the 30 mg/kg-day group. Maternal thyroid weights were increased in the 30.0 mg/kg-day group. Decreased colloid was present in male and female fetal thyroids in the 1.0 and 30.0 mg/kg-day groups. Maternal TSH was increased and T4 was decreased at all levels, and T3 was reduced at 30.0 mg/kg-day. Fetal TSH was increased at 1.0 and 30.0 mg/kg-day, T4 was reduced at 30.0 mg/kg-day, and T3 was decreased at all levels. The maternal no-observable-adverse-effect level (NOAEL) was 1.0 mg/kg-day; exposures of 30.0 mg/kg-day increased absolute and relative maternal thyroid weights and histopathology findings. The developmental NOAEL was 1.0 mg/kg-day; developmental delays in ossification occurred in the 30.0 mg/kg-day group. The colloid depletion in the thyroids and increased TSH and decreased T3 and T4 levels at lower exposures were considered adaptive and not adverse. No adverse effects on development at occurred levels that did not cause maternal toxicity. AP is not a selective developmental toxicant.
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Affiliation(s)
- Raymond G York
- Argus Research, Charles River Laboratories, Inc., Horsham, Pennsylvania 19044, USA.
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21
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Khan MA, Fenton SE, Swank AE, Hester SD, Williams A, Wolf DC. A Mixture of Ammonium Perchlorate and Sodium Chlorate Enhances Alterations of the Pitutary-Thyroid Axis Caused by the Individual Chemicals in Adult Male F344 Rats. Toxicol Pathol 2016; 33:776-83. [PMID: 16392172 DOI: 10.1080/01926230500449832] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Ammonium perchlorate (AP) and sodium chlorate (SC) have been detected in public drinking water supplies in many parts of the United States. These chemicals cause perturbations in pituitary-thyroid homeostasis in animals by competitively inhibiting iodide uptake, thus hindering the synthesis of thyroglobulin and reducing circulating T4 (thyroxine). Little is known about the short-term exposure effects of mixtures of perchlorate and chlorate. The present study investigated the potential for the response to a mixture of these chemicals on the pituitary-thyroid axis in rats to be greater than that induced by the individual chemicals. Adult male F-344 rats were exposed, via their drinking water, to the nominal concentrations of 0.1, 1.0, 10 mg/L AP or 10, 100, 1000 mg/L SC and their mixtures for 7 days. Serum T4 levels were significantly ( p < 0.05) reduced in rats following exposure to the mixtures, but not after exposure to the individual chemicals. Serum T3 (triiodothyronine) was not altered by treatment and TSH (thyroid stimulating hormone) was only increased after the high-dose chlorate treatment. Histological examination of the thyroid gland showed colloid depletion and hypertrophy of follicular epithelial cells in high-dose single chemical and all mixture-treated rats, while hyperplasia was observed only in some of the rats treated with mixtures (AP 10 + SC 100, AP 0.1 + SC 1000, and AP 10 + SC 1000 mg/L). These data suggest that short-term exposure to the mixture of AP and SC enhances the effect of either chemical alone on the pituitary-thyroid axis in rats.
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Affiliation(s)
- Moazzam A Khan
- National Research Council, Environmental Carcinogenesis Divisions, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA
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22
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Scientific Opinion on the risks to public health related to the presence of perchlorate in food, in particular fruits and vegetables. EFSA J 2014. [DOI: 10.2903/j.efsa.2014.3869] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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23
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Ducharme NA, Reif DM, Gustafsson JA, Bondesson M. Comparison of toxicity values across zebrafish early life stages and mammalian studies: Implications for chemical testing. Reprod Toxicol 2014; 55:3-10. [PMID: 25261610 DOI: 10.1016/j.reprotox.2014.09.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/21/2014] [Accepted: 09/15/2014] [Indexed: 12/12/2022]
Abstract
With the high cost and slow pace of toxicity testing in mammals, the vertebrate zebrafish has become a tractable model organism for high throughput toxicity testing. We present here a meta-analysis of 600 chemicals tested for toxicity in zebrafish embryos and larvae. Nineteen aggregated and 57 individual toxicity endpoints were recorded from published studies yielding 2695 unique data points. These data points were compared to lethality and reproductive toxicology endpoints analyzed in rodents and rabbits and to exposure values for humans. We show that although many zebrafish endpoints did not correlate to rodent or rabbit acute toxicity data, zebrafish could be used to accurately predict relative acute toxicity through the rat inhalation, rabbit dermal, and rat oral exposure routes. Ranking of the chemicals based on toxicity and teratogenicity in zebrafish, as well as human exposure levels, revealed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo(a)pyrene, and chlorpyrifos ranked in the top nine of all chemicals for these three categories, and as such should be considered high priority chemicals for testing in higher vertebrates.
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Affiliation(s)
- Nicole A Ducharme
- University of Houston, Department of Biology and Biochemistry, Center for Nuclear Receptors and Cell Signaling, Houston, TX 77204, USA
| | - David M Reif
- North Carolina State University, Department of Biological Sciences, Bioinformatics Research Center, Raleigh, NC 27695-7614, USA
| | - Jan-Ake Gustafsson
- University of Houston, Department of Biology and Biochemistry, Center for Nuclear Receptors and Cell Signaling, Houston, TX 77204, USA; Karolinska Institutet, Department of Biosciences and Nutrition, 14183 Huddinge, Sweden
| | - Maria Bondesson
- University of Houston, Department of Biology and Biochemistry, Center for Nuclear Receptors and Cell Signaling, Houston, TX 77204, USA.
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Sahana A, Banerjee A, Lohar S, Chottapadhyay A, Mukhopadhyay SK, Das D. Lighting of a rhodamine-based fluorescent lamp using ClO4− as a connector: detection by the naked eye and cell imaging studies of trace amounts of ClO4− ions. RSC Adv 2013. [DOI: 10.1039/c3ra41018h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Mendez W, Eftim SE. Biomarkers of perchlorate exposure are correlated with circulating thyroid hormone levels in the 2007-2008 NHANES. ENVIRONMENTAL RESEARCH 2012; 118:137-144. [PMID: 22749113 DOI: 10.1016/j.envres.2012.05.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 05/15/2012] [Accepted: 05/18/2012] [Indexed: 06/01/2023]
Abstract
Previous epidemiological studies provide conflicting evidence as to whether environmental perchlorate exposure can affect levels of circulating thyroid hormones in the general population. We investigated the statistical relationships between biomarkers of perchlorate exposure and serum thyroid hormone levels in 2007-2008 National Health and Nutrition Evaluation Survey (NHANES) subjects. Generalized additive mixed models (GAMMs) were developed to estimate the relationships between T3 and T4 levels and creatinine-adjusted urinary perchlorate excretion. The models included covariates related to gender, age, ethnicity, income, smoking status, prescription medications, and biomarkers of exposures to other goitrogenic ions and phthalate ester metabolites. Where necessary, relationships between hormone levels and covariates were represented as nonlinear smoothed terms. The effect of the hypothalamic-pituitary-thyroid (HPT) axis on serum hormone levels was taken into account by including a term for thyroid stimulating hormone (TSH) in the models. Regression coefficients for perchlorate were significant and negative in GAMMs predicting total T4 and free T3 levels in males, females, and for the entire cohort when phthalate ester biomarkers and other covariates were included. Coefficients for perchlorate were also significant and negative in regressions predicting free T4 levels in males and in the entire study population. The consistency of these results suggests that HPT axis controls do not completely compensate for small changes in thyroid hormone levels associated with perchlorate and phthalate ester exposures.
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26
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Lipscomb JC. How Differences in Enzyme Expression Can Translate into Pharmacokinetic Variance and Susceptibility to Toxicity. ACTA ACUST UNITED AC 2011. [DOI: 10.3109/713610281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kunisue T, Fisher JW, Kannan K. Modulation of thyroid hormone concentrations in serum of rats coadministered with perchlorate and iodide-deficient diet. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2011; 61:151-158. [PMID: 21573761 DOI: 10.1007/s00244-011-9677-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Accepted: 04/18/2011] [Indexed: 05/30/2023]
Abstract
Perchlorate can perturb thyroid hormone (TH) homeostasis by competitive inhibition of iodide uptake by the thyroid gland. Until recently, the effects of perchlorate on TH homeostasis were examined by measuring serum concentrations of THs by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis they are compromised by lack of adequate specificity. In this study, we determined the concentrations of six THs: L-thyroxine (T₄), 3,3',5-triiodo-L-thyronine (T₃), 3,3',5'-triiodo-L-thyronine (rT₃), 3,5-diiodo-L-thyronine, 3,3'-diiodo-L-thyronine, and 3-iodo-L-thyronine in the serum of rats administered perchlorate by isotope (¹³C₆-T₄)-dilution liquid chromatography-tandem mass spectrometry. The method recoveries for THs spiked into a serum matrix were between 97.0% and 115%, with a coefficient of variation of 2.1% to 9.4%. Rats were placed on an iodide-deficient or iodide-sufficient diet for 2.5 months, and for the last 2 weeks of that period they were provided drinking water either without or with perchlorate (10 mg/kg body weight/day). No significant differences in serum concentrations of T₃ and T₄ were observed between rats given iodide-deficient and iodide-sufficient diets for 2 or 2.5 months. After 24 h of perchlorate exposure, significantly lower concentrations of T₃ and T₄ were found in the serum of rats administered the iodide-deficient diet but not in rats administered the iodide-sufficient diet. However, after 2 weeks of perchlorate exposure, TH levels in rats fed the iodide-sufficient diet were also significantly lower than those in control rats. Our results suggest that perchlorate affects TH homeostasis and that such effects are more pronounced under iodide-deficient nutrition.
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Affiliation(s)
- Tatsuya Kunisue
- Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA
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28
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Hatzistavros VS, Kallithrakas-Kontos NG. Determination of Trace Perchlorate Concentrations by Anion-Selective Membranes and Total Reflection X-ray Fluorescence Analysis. Anal Chem 2011; 83:3386-91. [DOI: 10.1021/ac103295a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vasilios S. Hatzistavros
- Analytical and Environmental Chemistry Laboratory, University Campus, Technical University of Crete, GR-73100 Chania, Greece
| | - Nikolaos G. Kallithrakas-Kontos
- Analytical and Environmental Chemistry Laboratory, University Campus, Technical University of Crete, GR-73100 Chania, Greece
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Sarkar S, Khillare PS, Jyethi DS, Hasan A, Parween M. Chemical speciation of respirable suspended particulate matter during a major firework festival in India. JOURNAL OF HAZARDOUS MATERIALS 2010; 184:321-330. [PMID: 20817345 DOI: 10.1016/j.jhazmat.2010.08.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 07/29/2010] [Accepted: 08/10/2010] [Indexed: 05/29/2023]
Abstract
Ambient respirable particles (PM ≤ 10 μm, denoted by PM(10)) were characterized with respect to 20 elements, 16 polycyclic aromatic hydrocarbons (PAHs), elemental and organic carbon (EC and OC) during a major firework event-the "Diwali" festival in Delhi, India. The event recorded extremely high 24-h PM(10) levels (317.2-616.8 μg m(-3), 6-12 times the WHO standard) and massive loadings of Ba (16.8 μg m(-3), mean value), K (46.8 μg m(-3)), Mg (21.3 μg m(-3)), Al (38.4 μg m(-3)) and EC (40.5 μg m(-3)). Elemental concentrations as high as these have not been reported previously for any firework episode. Concentrations of Ba, K, Sr, Mg, Na, S, Al, Cl, Mn, Ca and EC were higher by factors of 264, 18, 15, 5.8, 5, 4, 3.2, 3, 2.7, 1.6 and 4.3, respectively, on Diwali as compared to background values. It was estimated that firework aerosol contributed 23-33% to ambient PM(10) on Diwali. OC levels peaked in the post-Diwali samples, perhaps owing to secondary transformation processes. Atmospheric PAHs were not sourced from fireworks; instead, they correlated well with changes in traffic patterns indicating their primary source in vehicular emissions. Overall, the pollutant cocktail generated by the Diwali fireworks could be best represented with Ba, K and Sr as tracers. It was also found that chronic exposure to Diwali pollution is likely to cause at least a 2% increase in non-carcinogenic hazard index (HI) associated with Al, Mn and Ba in the exposed population.
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Affiliation(s)
- Sayantan Sarkar
- Environmental Monitoring and Management Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Pandit S Khillare
- Environmental Monitoring and Management Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Darpa S Jyethi
- Environmental Monitoring and Management Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Amreen Hasan
- Environmental Monitoring and Management Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Musarrat Parween
- Environmental Monitoring and Management Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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Kunisue T, Fisher JW, Fatuyi B, Kannan K. A method for the analysis of six thyroid hormones in thyroid gland by liquid chromatography–tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1725-30. [DOI: 10.1016/j.jchromb.2010.04.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/14/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
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The Epidemiology of Environmental Perchlorate Exposure and Thyroid Function: A Comprehensive Review. J Occup Environ Med 2010; 52:653-60. [DOI: 10.1097/jom.0b013e3181e31955] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schier JG, Wolkin AF, Valentin-Blasini L, Belson MG, Kieszak SM, Rubin CS, Blount BC. Perchlorate exposure from infant formula and comparisons with the perchlorate reference dose. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2010; 20:281-287. [PMID: 19293845 DOI: 10.1038/jes.2009.18] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Accepted: 01/20/2009] [Indexed: 05/27/2023]
Abstract
Perchlorate exposure may be higher in infants compared with older persons, due to diet (infant formula) and body weight versus intake considerations. Our primary objective was to quantitatively assess perchlorate concentrations in commercially available powdered infant formulas (PIFs). Secondary objectives were: (1) to estimate exposure in infants under different dosing scenarios and compare them with the perchlorate reference dose (RfD); (2) estimate the perchlorate concentration in water used for preparing PIFs that would result in a dose exceeding the RfD; and (3) estimate iodine intakes from PIFs. We quantified perchlorate levels in three samples (different lot numbers) of reconstituted PIF (using perchlorate-free water) from commercial brands of PIF in each of the following categories: bovine milk-based with lactose, soy-based, bovine milk-based but lactose-free, and elemental (typically consisting of synthetic amino acids). Exposure modeling was conducted to determine whether the RfD might be exceeded in 48 dosing scenarios that were dependent on age, centile energy intake per unit of body weight, body weight percentile, and PIF perchlorate concentration. We obtained three different samples in each of the five brands of bovine- and soy-based PIF, three different samples in each of the three brands of lactose-free PIF, and three different samples in two brands of elemental PIF. The results were as follows: bovine milk-based with lactose (1.72 microg/l, range: 0.68-5.05); soy-based (0.21 microg/l, range: 0.10-0.44); lactose-free (0.27 microg/l, range: 0.03-0.93); and elemental (0.18 microg/l, range: 0.08-0.4). Bovine milk-based PIFs with lactose had a significantly higher concentration of perchlorate (P<0.05) compared with all. Perchlorate was a contaminant of all commercially available PIFs tested. Bovine milk-based PIFs with lactose had a significantly higher perchlorate concentration perchlorate than soy, lactose-free, and elemental PIFs. The perchlorate RfD may be exceeded when certain bovine milk-based PIFs are ingested and/or when PIFs are reconstituted with perchlorate-contaminated water.
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Affiliation(s)
- Joshua G Schier
- Division of Environmental Hazards and Health Effects, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
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Martin DF, Kondis NP, Alldredge RL. Effectiveness of removal of aqueous perchlorate by Cuprilig, a copper(II) derivative of Octolig. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:188-191. [PMID: 19123099 DOI: 10.1080/10934520802539848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The present study describes the effectiveness of removal of perchlorate ion by Octolig a commercially available immobilized ligand, IMLIG, and by Cuprilig, the cupric ion derivative of this material. Octolig consists of polyethylenediamine moieties covalently bound to a high-surface area silica gel (CAS Registry number = 404899-06-5). Perchlorate in drinking water is a nuisance anion that escapes from firms that produce rocket fuel, batteries, and fireworks and becomes a contaminant of groundwater. It may also be a natural component of the environment. Perchlorate ion can interfere with thyroid function and may also cause birth defects. Perchlorate contamination of water supplies is serious because of the difficulty in removing it, especially in the western United States where a combination of drought and water shortages exacerbate the problems of supplying safe drinking water to an increasing population. In this study, aqueous solutions were passed over a chromatography column containing samples of Cuprilig. Test water contained 70 microg perchlorate/L and effluent was below detection level (< 1 microg/L. Equally good results were obtained for Octolig in deionized water and in well water. Analyses were performed by a commercial laboratory. Mechanisms of interaction are proposed.
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Affiliation(s)
- Dean F Martin
- Institute for Environmental Studies, Department of Chemistry, University of South Florida, Tampa, Florida, USA.
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Oldi JF, Kannan K. Analysis of perchlorate in human saliva by liquid chromatography-tandem mass spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:142-147. [PMID: 19209597 DOI: 10.1021/es802575c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Perchlorate is both a naturally occurring anion and the disassociated anion of manufactured perchlorate salts. Because perchlorate has the abilityto blockthe uptake of iodide bythe thyroid gland, it is considered a potent thyroid hormone disruptor in humans. Methods for the analysis of perchlorate in biological matrices are needed to enable assessment of exposures and to elucidate adverse health outcomes. This study describes a method for the analysis of perchlorate in human saliva samples, using a simple dilution and ultrafiltration technique. Quantification of perchlorate in saliva samples using isotopically labeled standards (Cl18O4) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers great selectivity and sensitivity. Matrix effects in perchlorate analysis are compensated by spiking of saliva samples with an isotopically labeled internal standard for perchlorate. The LC-MS/MS calibration was found to be linear over the range from 0.01 to 50 ng/mL for 100 microL injections (i.e., 1-5000 pg injection). Fortified blank and matrix spike recoveries were between 93% and 97%, when spiked at a 2 ng/mL level. Relative standard deviations (RSDs) of daily calibration checks and fortified blanks were < or =10%. The relative percent difference, in laboratory duplicate analysis of original samples, was less than 1%. The method quantitation limit (LOQ) was determined to be 0.4 ng/mL, which includes a sample dilution factor. Salivary concentrations of a convenience sample of 83 persons working and/or living in Albany County of New York State ranged from 0.4 to 37 ng/mL with a mean concentration of 5.3 ng/mL Including sample preparation steps, 25 samples can be analyzed within 8 h. This selective and rapid method for analysis of perchlorate in human saliva will enable investigators and scientists to determine the extent of an individual's perchlorate exposure and, potentially, the compound's effects on human health. Analysis of perchlorate in saliva from a population (n = 86) with no major sources of exposures, using the method developed in this study, suggests the ubiquitous occurrence of this compound in saliva.
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Affiliation(s)
- John F Oldi
- Wadsworth Center, New York State Department of Health, Albany, New York 12201-0509, USA
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Patel A, Zuo G, Lehman SG, Badruzzaman M, Clifford DA, Roberts DJ. Fluidized bed reactor for the biological treatment of ion-exchange brine containing perchlorate and nitrate. WATER RESEARCH 2008; 42:4291-4298. [PMID: 18718630 DOI: 10.1016/j.watres.2008.07.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 07/07/2008] [Accepted: 07/10/2008] [Indexed: 05/26/2023]
Abstract
The removal of perchlorate and nitrate from contaminated drinking water using regenerable ion-exchange processes produces a high salt brine (3-10% NaCl) laden with high concentrations of perchlorate and nitrate. This bench-scale research describes the operation of acetate-fed granular activated carbon (GAC) based fluidized bed reactors (FBR) for perchlorate-only, and combined nitrate and perchlorate removal from synthetic brine (6% NaCl). The GAC was inoculated with a salt-tolerant culture developed by the authors and used previously in batch systems. An FBR was an effective design for perchlorate reduction and exhibited first-order degradation kinetics with respect to perchlorate concentrations. Nitrate was also removed by the organisms in the column and had no negative effects on the removal of perchlorate using the FBR design. However, at higher concentrations of nitrate the FBR was more difficult to operate due to loss of carbon and biomass from the formation of nitrogen bubbles and the high recycle flow rates needed.
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Affiliation(s)
- A Patel
- Department of Civil and Environmental Engineering, University of Houston, Houston, TX 77204-4003, United States
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Steinhauser G, Klapötke T. Pyrotechnik mit dem “Ökosiegel”: eine chemische Herausforderung. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704510] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Steinhauser G, Klapötke T. “Green” Pyrotechnics: A Chemists' Challenge. Angew Chem Int Ed Engl 2008; 47:3330-47. [DOI: 10.1002/anie.200704510] [Citation(s) in RCA: 368] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Perchlorate: overview of risks and regulation. Food Chem Toxicol 2008; 46:2307-15. [PMID: 18440116 DOI: 10.1016/j.fct.2008.03.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Revised: 03/03/2008] [Accepted: 03/04/2008] [Indexed: 11/22/2022]
Abstract
The extent to which perchlorate, which occurs naturally and as an industrial contaminant, should or should not be regulated has become controversial. This review examines a number of inconsistent conclusions that have been drawn based on thyroid hormone serum concentrations, urinary iodine concentrations, and perchlorate exposure among women participating in the 2000-2001 National Health and Nutrition Examination Survey (NHANES) and based on the body of epidemiologic and clinical evidence reporting no associations between effects on thyroid hormones and similar or much higher levels of perchlorate exposure. For example, studies associating perchlorate with thyroid effects at low exposures did not control for anti-thyroid agents with modes of action that differ from that of perchlorate, such as some organochlorines. Available evidence does not support a causal relationship between changes in thyroid hormone levels and current environmental levels of perchlorate exposure but does support the conclusion that the US Environmental Protection Agency's reference dose (RfD) for perchlorate is conservatively health-protective. However, potential perchlorate risks are unlikely to be distinguishable from the ubiquitous background of naturally occurring substances present at much higher exposures that can affect the thyroid via the same biological mode of action as perchlorate, such as nitrate and thiocyanate. Risk management approaches that account for both aggregate and cumulative exposures and that consider the larger public health context in which exposures are occurring are desirable.
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Abstract
Thyrotoxicosis is a condition resulting from elevated levels of thyroid hormone. In this article, the authors review the presentation, diagnosis, and management of various causes of thyrotoxicosis.
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Affiliation(s)
- Bindu Nayak
- Division of Endocrinology and Metabolism, Georgetown University Hospital, 4000 Reservoir Road, Building D, Suite 232, Washington, DC 20007, USA.
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41
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Cheng Q, Smith EE, Liu F, Gentle A, Hooper MJ, Anderson TA. Effects of perchlorate on sodium-iodide symporter and pendrin gene expression in deer mice. ENVIRONMENTAL TOXICOLOGY 2007; 22:390-8. [PMID: 17607730 DOI: 10.1002/tox.20271] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Effects of perchlorate on sodium-iodide symporter (NIS) and pendrin gene expression in deer mice kidney and stomach were investigated. This was accomplished by isolating a partial cDNA sequence of deer mice NIS gene of 425 bps, and quantitatively analyzing NIS mRNA expression in various deer mouse tissues. The highest NIS expression level was in the stomach, followed by testes, brain, and large intestine; very low expression of NIS was observed in the lung, kidney, heart, and liver. Exposure to perchlorate through drinking water for 28 days did not significantly increase NIS gene expression in the kidney and stomach, and pendrin gene expression in the kidney. In a depuration experiment in which deer mice were exposed to perchlorate for 8-h followed by an 88-h depuration period, no significant difference was observed between the low and high exposure groups in terms of NIS or pendrin gene expression in the kidney or stomach at the end of the experiment. Furthermore, no significant linear relationship was observed between gene expression (either NIS or pendrin) in the kidney and perchlorate mass excreted via urine at day 28, average daily excretion, or total excretion mass over the 28 day exposure. Several factors could influence the effect of perchlorate exposure on NIS and pendrin gene expression in the stomach and kidney, including (1) pre-exposure to trace perchlorate through food and water perhaps resulting in adaptation (or tolerance) in these animals; (2) metabolism of perchlorate in deer mice causing only 46-61% perchlorate excreted into urine. It is also possible that there is no effect of perchlorate exposure and/or urinary excretion on NIS and pendrin gene expression, particularly in the kidney.
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Affiliation(s)
- Qiuqiong Cheng
- Department of Environmental Toxicology, The Institute of Environmental and Human Health, Texas Tech University, Lubbock, Texas 79409-1163, USA.
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Helbing CC, Ji L, Bailey CM, Veldhoen N, Zhang F, Holcombe GW, Kosian PA, Tietge J, Korte JJ, Degitz SJ. Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay. Part 2. Effects on the tail and hindlimb. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2007; 82:215-26. [PMID: 17399805 DOI: 10.1016/j.aquatox.2007.02.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 02/01/2007] [Accepted: 02/03/2007] [Indexed: 05/14/2023]
Abstract
Thyroid hormones (TH), thyroxine (T(4)) and 3,5,3'-triiodothyronine (T(3)), play crucial roles in regulation of growth, development and metabolism in vertebrates and are targets for endocrine disruptive agents. Perturbations in TH action can contribute to the development of disease states and the US Environmental Protection Agency is developing a high throughput screen using TH-dependent metamorphosis of the Xenopus laevis tadpole as an assay platform. Currently this methodology relies on external morphological endpoints and changes in central thyroid axis parameters. However, exposure-related changes in gene expression in TH-sensitive tissue types that occur over shorter time frames have the potential to augment this screen. Using a combination of cDNA array and real time quantitative polymerase chain reaction (QPCR) analyses, this study identifies molecular markers in tissues peripheral to the central thyroid axis. We examine the hindlimb and tail of tadpoles up to 96 h of continuous exposure to T(3), T(4), methimazole, propylthiouracil, or perchlorate. Several novel biomarker candidates are indicated that include transcripts encoding importin, RNA helicase II/Gu, and defender against death protein, DAD1. In combination with previously-identified biomarker candidates, these transcripts will greatly augment the predictive and diagnostic power of the Xenopus metamorphosis assay for perturbation of TH action.
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Affiliation(s)
- Caren C Helbing
- Department of Biochemistry and Microbiology, PO Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6, Canada.
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Helbing CC, Bailey CM, Ji L, Gunderson MP, Zhang F, Veldhoen N, Skirrow RC, Mu R, Lesperance M, Holcombe GW, Kosian PA, Tietge J, Korte JJ, Degitz SJ. Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay. Part 1. Effects on the brain. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2007; 82:227-41. [PMID: 17403546 DOI: 10.1016/j.aquatox.2007.02.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 02/01/2007] [Accepted: 02/03/2007] [Indexed: 05/14/2023]
Abstract
Thyroid hormones (TH), thyroxine (T(4)) and 3,5,3'-triiodothyronine (T(3)), play crucial roles in regulation of growth, development and metabolism in vertebrates and their actions are targets for endocrine disruptive agents. Perturbations in TH action can contribute to the development of disease states and the US Environmental Protection Agency is developing a high throughput screen using TH-dependent amphibian metamorphosis as an assay platform. Currently this methodology relies on external morphological endpoints and changes in central thyroid axis parameters. However, exposure-related changes in gene expression in TH-sensitive tissue types that occur over shorter time frames have the potential to augment this screen. This study aims to characterize and identify molecular markers in the tadpole brain. Using a combination of cDNA array analysis and real time quantitative polymerase chain reaction (QPCR), we examine the brain of tadpoles following 96 h of continuous exposure to T(3), T(4), methimazole, propylthiouracil, or perchlorate. This tissue was more sensitive to T(4) rather than T(3), even when differences in biological activity were taken into account. This implies that a simple conversion of T(4) to T(3) cannot fully account for T(4) effects on the brain and suggests distinctive mechanisms of action for the two THs. While the brain shows gene expression alterations for methimazole and propylthiouracil, the environmental contaminant, perchlorate, had the greatest effect on the levels of mRNAs encoding proteins important in neural development and function. Our data identify gene expression profiles that can serve as exposure indicators of these chemicals.
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Affiliation(s)
- Caren C Helbing
- Department of Biochemistry and Microbiology, PO Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia, V8W 3P6, Canada.
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Ju X, Field JA, Sierra-Alvarez R, Salazar M, Bentley H, Bentley R. Chemolithotrophic perchlorate reduction linked to the oxidation of elemental sulfur. Biotechnol Bioeng 2007; 96:1073-82. [PMID: 17009322 DOI: 10.1002/bit.21197] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Perchlorate (ClO(4)(-)) contamination of ground and surface water has been recently recognized as a widespread environmental problem. Biological methods offer promising perspectives of perchlorate remediation. Facultative anaerobic bacteria couple the oxidation of organic and inorganic electron-donating substrates to the reduction of perchlorate as a terminal electron acceptor, converting it completely to the benign end-product, chloride. Insoluble inorganic substrates are of interest for low maintenance bioreactor or permeable reactive barrier systems because they can provide a long-term supply of electron donor without generating organic residuals. The main objective of this research was to investigate the feasibility of utilizing elemental sulfur (S(0)) as an insoluble electron donor for the biological reduction of perchlorate. A chemolithotrophic enrichment culture derived from aerobic activated sludge was obtained which effectively coupled the oxidation of elemental sulfur to sulfate with the reduction of perchlorate to chloride and gained energy from the process for cell growth. The enrichment culture grew at a rate of 0.41 or 0.81 1/d in the absence and presence of added organic carbon for cell growth, respectively. The enrichment culture was also shown to carry out sulfur disproportionation to a limited extent as evidenced by the formation of sulfide and sulfate in the absence of added electron acceptor. When nitrate and perchlorate were added together, the two electron acceptors were removed simultaneously after an initial partial decrease in the nitrate concentration.
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Affiliation(s)
- Xiumin Ju
- Department of Chemical and Environmental Engineering, University of Arizona, PO Box 210011, Tucson, Arizona 85721-0011, USA
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Abstract
Euthyroid women experience dramatic changes in their thyroid physiology in order to accommodate the presence of placental and fetal tissues. These adaptations to the pregnant state make it crucial to develop reliable trimester-specific intervals for thyroid parameters. Use of non-pregnant reference intervals could lead to erroneous assessment of thyroid status in this rapidly changing hormonal environment. Only with a full appreciation of physiologic changes in thyroid parameters during a euthyroid pregnancy, can thyroid dysfunction be appropriately diagnosed and managed. Iodine sufficiency during pregnancy can be achieved with supplementation using a multivitamin. Both hypothyroidism and hyperthyroidism should be diagnosed using the appropriate reference intervals for pregnancy. Hypothyroid women are best treated with a specific brand of levothyroxine. Hypothyroidism should ideally be treated prior to conception. If newly recognized during pregnancy, it should be fully treated as early as possible. Frequent monitoring of thyroid status is essential as many women demonstrate an increased requirement for thyroid hormone during the first trimester. Although mild hyperthyroidism may be well tolerated during pregnancy, overt hyperthyroidism requires treatment. Thionamides are the mainstay of therapy. Following their initiation, close monitoring is required to avoid maternal and fetal hypothyroidism. There are occasional circumstances when other medical therapy or surgical therapy may be employed for hyperthyroidism. Thyroidectomy is generally safe in the second trimester in an appropriately prepared woman. There is limited data about the role and safety of oral contrast agents, iodine, amiodarone, and perchlorate. Radioiodine therapy is contradicted during pregnancy.
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Affiliation(s)
- Thien-Giang Bach-Huynh
- Division of Endocrinology and Metabolism, Georgetown University, Suite 232, Bldg. D, 4000 Reservoir Road, NW, Washington, DC 20007, USA
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46
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Bannerman DD, Paape MJ, Baldwin RL, Rice CP, Bialek K, Capuco AV. Effect of Mastitis on Milk Perchlorate Concentrations in Dairy Cows. J Dairy Sci 2006; 89:3011-9. [PMID: 16840617 DOI: 10.3168/jds.s0022-0302(06)72574-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Recent surveys have identified the presence of perchlorate, a natural compound and environmental contaminant, in forages and dairy milk. The ingestion of perchlorate is of concern because of its ability to competitively inhibit iodide uptake by the thyroid and to impair synthesis of thyroid hormones. A recent study established that milk perchlorate concentrations in cattle highly correlate with perchlorate intake. However, there is evidence that up to 80% of dietary perchlorate is metabolized in clinically healthy cows, thereby restricting the available transfer of ingested perchlorate into milk. The influence of mastitis on milk perchlorate levels, where there is an increase in mammary vascular permeability and an influx of blood-derived components into milk, remains unknown. The present study examined the effect of experimentally induced mastitis on milk perchlorate levels in cows receiving normal and perchlorate-supplemented diets. Over a 12-d period, cows were ruminally infused with 1 L/d of water or water containing 8 mg of perchlorate. Five days after the initiation of ruminal infusions, experimental mastitis was induced by the intramammary infusion of 100 microg of bacterial lipopolysaccharide (LPS). Contralateral quarters infused with phosphate-buffered saline served as controls. A significant reduction in milk perchlorate concentration was observed in the LPS-challenged glands of animals ruminally infused with either water or perchlorate. In control glands, milk perchlorate concentrations remained constant throughout the study. A strong negative correlation was identified between mammary vascular permeability and milk perchlorate concentrations in LPS-infused glands. These findings, in the context of a recently published study, suggest that an active transport process is operative in the establishment of a perchlorate concentration gradient across the blood-mammary gland interface, and that increases in mammary epithelial and vascular endothelial permeability lead to a net outflow of milk perchlorate. The overall finding that mastitis results in lower milk perchlorate concentrations suggests that changes in udder health do not necessitate increased screening of milk for perchlorate.
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Affiliation(s)
- D D Bannerman
- Bovine Functional Genomics Laboratory, USDA, ARS, Beltsville, MD 20705 , USA.
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Bradford CM, Park JW, Rinchard J, Anderson TA, Liu F, Theodorakis CW. Uptake and elimination of perchlorate in eastern mosquitofish. CHEMOSPHERE 2006; 63:1591-7. [PMID: 16303168 DOI: 10.1016/j.chemosphere.2005.08.073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Revised: 08/18/2005] [Accepted: 08/30/2005] [Indexed: 05/05/2023]
Abstract
The purpose of this study was to investigate the uptake and elimination of perchlorate in eastern mosquitofish (Gambusia holbrooki). Fish were exposed to 0.1-1000 mg/l sodium perchlorate for 12h, 1, 2, 5, 10, and 30 days, and perchlorate was determined in whole body extracts. Perchlorate was not detected in mosquitofish exposed to the low concentrations of perchlorate (0, 0.1, and 1mg/l sodium perchlorate), regardless of the exposure time, whereas it was detected when fish were exposed to 10, 100, and 1000 mg/l. The tissue concentrations were approximately 10 times less than that in the water. There was no difference in the uptake of perchlorate depending upon the exposure time, however, a difference in perchlorate uptake depending upon the concentration of the exposure dose (P<0.001) was observed. Uptake (K(u)) and elimination (K(e)) rate constants were 0.09 l/mg day and 0.70 day(-1), respectively. The half-life (T1/2) of perchlorate was 0.99 day. Thus, it appears that perchlorate is rapidly taken up and eliminated in eastern mosquitofish. These results are critical and may be used to develop models of fate, effects, and transport of perchlorate in natural systems, as well as to assess ecological risk in affected ecosystems.
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Affiliation(s)
- Carrie M Bradford
- The Institute of Environmental and Human Health, Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163, USA
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Yu L, Cheng Q, Cañas J, Valentin-Blasini L, Blount BC, Anderson T. Challenges in determining perchlorate in biological tissues and fluids: Implications for characterizing perchlorate exposure. Anal Chim Acta 2006; 567:66-72. [PMID: 17723380 DOI: 10.1016/j.aca.2005.12.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Revised: 12/02/2005] [Accepted: 12/22/2005] [Indexed: 10/25/2022]
Abstract
The ability to measure environmental contaminants in biological tissues and fluids is important in the characterization of exposure. However, the analysis of certain contaminants in these matrices presents significant challenges. Perchlorate (ClO4-) has emerged as a potential contaminant of concern primarily in drinking water and also in contaminated food. Significant advances have been made in the analysis of perchlorate in environmental matrices (water, soil) by ion chromatography (IC). In contrast, the analysis of perchlorate in extracts of biological tissues and fluids (vegetation, organs, milk, blood, urine, etc.) presents several challenges including small sample sizes, extracts with high matrix conductivity, and co-elution of other ions during IC analysis. To be able to detect low concentrations of perchlorate in biological samples, interferences must be removed or minimized, such as through the use of preparative chromatography cleanup techniques and/or alternative analytical methods less susceptible to common interferences (preconcentration or mass spectrometric detection). We present discussion and examples of the challenges encountered in the analysis of tissue extracts and fluids for perchlorate by IC and how some of those analytical challenges have been overcome.
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Affiliation(s)
- Lu Yu
- Department of Chemistry, Stephen F. Austin State University, Box 13006, Nacogdoches, TX 75961, United States
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Huynh MHV, Hiskey MA, Meyer TJ, Wetzler M. Green primaries: environmentally friendly energetic complexes. Proc Natl Acad Sci U S A 2006; 103:5409-12. [PMID: 16567623 PMCID: PMC1459368 DOI: 10.1073/pnas.0600827103] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Primary explosives are used in small quantities to generate a detonation wave when subjected to a flame, heat, impact, electric spark, or friction. Detonation of the primary explosive initiates the secondary booster or main-charge explosive or propellant. Long-term use of lead azide and lead styphnate as primary explosives has resulted in lead contamination at artillery and firing ranges and become a major health hazard and environmental problem for both military and civilian personnel. Devices using lead primary explosives are manufactured by the tens of millions every year in the United States from primers for bullets to detonators for mining. Although substantial synthetic efforts have long been focused on the search for greener primary explosives, this unresolved problem has become a "holy grail" of energetic materials research. Existing candidates suffer from instability or excessive sensitivity, or they possess toxic metals or perchlorate. We report here four previously undescribed green primary explosives based on complex metal dianions and environmentally benign cations, (cat)(2)[M(II)(NT)(4)(H(2)O)(2)] (where cat is NH(4)(+) or Na(+), M is Fe(2+) or Cu(2+), and NT(-) is 5-nitrotetrazolato-N(2)). They are safer to prepare, handle, and transport than lead compounds, have comparable initiation efficiencies to lead azide, and offer rapid reliable detonation comparable with lead styphnate. Remarkably, they possess all current requirements for green primary explosives and are suitable to replace lead primary explosives in detonators. More importantly, they can be synthesized more safely, do not pose health risks to personnel, and cause much less pollution to the environment.
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Affiliation(s)
- My Hang V. Huynh
- *Dynamic Experimentation Division, DX-2: High Explosives Science and Technology, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Michael A. Hiskey
- *Dynamic Experimentation Division, DX-2: High Explosives Science and Technology, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Thomas J. Meyer
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599; and
- To whom correspondence should be addressed. E-mail:
| | - Modi Wetzler
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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York RG, Lewis E, Brown WR, Girard MF, Mattie DR, Funk KA, Strawson JS. Refining the effects observed in a developmental neurobehavioral study of ammonium perchlorate administered orally in drinking water to rats. I. Thyroid and reproductive effects. Int J Toxicol 2006; 24:403-18. [PMID: 16393933 DOI: 10.1080/10915810500366765] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A recent study further investigated the potential effects of maternal thyroid function and morphology on fetal development upon maternal exposure to ammonium perchlorate during gestation and lactation. Female Sprague-Dawley rats (25/group) were given continual access to 0 (carrier), 0.01, 0.1, 1.0, and 30.0 mg/kg-day perchlorate in drinking water beginning 2 weeks prior to cohabitation through lactation day 10. Maternal, fetal, and pup serum thyroid hormone (thyroid-stimulating hormone [TSH], triiodo thyronine [T(3)], thyroxine [T(4)]) levels and thyroid histopathology were evaluated on gestation day 21, and lactation days 5, 10, and 22. No effects of exposure were observed on cesarean-sectioning, litter parameters, or fetal alterations. Reproductive parameters, including gestation length, number of implants, litter size, pup viability, and lactation indices, were comparable among all groups. Thyroid weights of dams sacrificed on gestation day 21, and lactation days 10 and 22 were significantly increased at 30.0 mg/kg-day. Increased thyroid weights were observed in male and female pups as early as postpartum days 5 and 10, respectively. Changes in maternal and neonatal thyroid histopathology were detectable at 1.0 mg/kg-day exposure. The maternal no-observable-effect level (NOEL) was 0.1 mg/kg-day (follicular cell hyperplasia was present at 1.0 and 30.0 mg/kg-day). The developmental NOEL was less than 0.01 mg/kg-day; thyroid weights of postpartum day 10 pups were increased at all exposures. Colloid depletion at 1.0 and 30.0 mg/kg-day exposures and changes of hormone levels at all exposures were considered an adaptive effect and appeared reversible in the rodent.
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Affiliation(s)
- Raymond G York
- Charles River Laboratories, Preclinical Services, 905 Sheehy Drive, Horsham, PA 19044, USA.
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