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Wallace DA, Gallagher JP, Peterson SR, Ndiaye-Gueye S, Fox K, Redline S, Johnson DA. Is exposure to chemical pollutants associated with sleep outcomes? A systematic review. Sleep Med Rev 2023; 70:101805. [PMID: 37392613 PMCID: PMC10528206 DOI: 10.1016/j.smrv.2023.101805] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 05/25/2023] [Accepted: 06/08/2023] [Indexed: 07/03/2023]
Abstract
Environmental exposures may influence sleep; however, the contributions of environmental chemical pollutants to sleep health have not been systematically investigated. We conducted a systematic review to identify, evaluate, summarize, and synthesize the existing evidence between chemical pollutants (air pollution, exposures related to the Gulf War and other conflicts, endocrine disruptors, metals, pesticides, solvents) and dimensions of sleep health (architecture, duration, quality, timing) and disorders (sleeping pill use, insomnia, sleep-disordered breathing)). Of the 204 included studies, results were mixed; however, the synthesized evidence suggested associations between particulate matter, exposures related to the Gulf War, dioxin and dioxin-like compounds, and pesticide exposure with worse sleep quality; exposures related to the Gulf War, aluminum, and mercury with insomnia and impaired sleep maintenance; and associations between tobacco smoke exposure with insomnia and sleep-disordered breathing, particularly in pediatric populations. Possible mechanisms relate to cholinergic signaling, neurotransmission, and inflammation. Chemical pollutants are likely key determinants of sleep health and disorders. Future studies should aim to evaluate environmental exposures on sleep across the lifespan, with a particular focus on developmental windows and biological mechanisms, as well as in historically marginalized or excluded populations.
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Affiliation(s)
- Danielle A Wallace
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Jayden Pace Gallagher
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Shenita R Peterson
- Woodruff Health Sciences Center Library, Emory University, Atlanta, GA, USA
| | - Seyni Ndiaye-Gueye
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Kathleen Fox
- Woodruff Health Sciences Center Library, Emory University, Atlanta, GA, USA
| | - Susan Redline
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Dayna A Johnson
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA; Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Sharma P, Nanda K, Yadav M, Shukla A, Srivastava SK, Kumar S, Singh SP. Remediation of noxious wastewater using nanohybrid adsorbent for preventing water pollution. CHEMOSPHERE 2022; 292:133380. [PMID: 34953871 DOI: 10.1016/j.chemosphere.2021.133380] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/13/2021] [Accepted: 12/18/2021] [Indexed: 06/14/2023]
Abstract
Removal of toxic elements from wastewater effluent has got a lot of attention because of their severe negative effects on human and environmental health. In the past few years, rapid urbanization and industrial activities in developing countries have exacerbated the destruction of the environment. Most of the wastewater effluents are discharged untreated or inadequately treated, which has become a major concern due to its impact on sustainability and the environment. This is imperative to implement, innovative and resourceful wastewater treatment technologies requiring low investment. Among the various treatment technologies, cutting-edge processes in nano-material sciences have recently piqued the interest of scientists. Nanohybrid absorbents have the potential in improving wastewater treatment and increase water supply by utilizing unconventional water resources. Carbon nanotubes, titanium oxide, manganese oxide, activated carbon (AC), magnesium oxide, graphene, ferric oxides, and zinc oxide are examples of nano-adsorbents that are used to eliminate pollutants. This also demonstrated the effective removal of contaminants along with the harmful effects of chemicals, colorants, and metals found in wastewater. The present manuscript examines potential advances in nanotechnology in wastewater treatment for the prevention of water and soil pollution. This systematic review aims to highlight the importance of nanohybrid absorbents treatment technology for wastewater treatment and to explain how nanohybrid absorbents have the potential to revolutionize industrial pollution. There are also other published review articles on this topic but the present review covers an in-depth information on nano-adsorbents and their targeted contaminants.
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Affiliation(s)
- Pooja Sharma
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur, 440 020, India.
| | - Kavita Nanda
- Plant Molecular Biology Laboratory, Department of Botany, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208 001, India
| | - Mamta Yadav
- Plant Molecular Biology Laboratory, Department of Botany, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208 001, India
| | - Ashutosh Shukla
- Plant Molecular Biology Laboratory, Department of Botany, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208 001, India
| | - Sudhir Kumar Srivastava
- Chemical Research Laboratory, Department of Chemistry, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208001, India
| | - Sunil Kumar
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur, 440 020, India.
| | - Surendra Pratap Singh
- Plant Molecular Biology Laboratory, Department of Botany, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208 001, India.
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Abstract
Metal exposure is pervasive and not limited to sporadic poisoning events or toxic waste sites. Hundreds of millions of people around the globe are affected by chronic metal exposure, which is associated with serious health concerns, including cancer, as demonstrated in a variety of studies at the molecular, systemic, and epidemiologic levels. Metal-induced toxicity and carcinogenicity are sophisticated and complex in nature. This review provides a broad context and holistic view of currently available studies on the mechanisms of metal-induced carcinogenesis. Specifically, we focus on the five most prevalent carcinogenic metals, arsenic, nickel, cadmium, chromium, and beryllium, and their potential to drive carcinogenesis in humans. A comprehensive understanding of the mechanisms behind the development of metal-induced cancer can provide valuable insights for therapeutic intervention involving molecular targets in metal-induced carcinogenesis.
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Affiliation(s)
- Qiao Yi Chen
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
| | - Thomas DesMarais
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
| | - Max Costa
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
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Siblerud R, Mutter J, Moore E, Naumann J, Walach H. A Hypothesis and Evidence That Mercury May be an Etiological Factor in Alzheimer's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E5152. [PMID: 31861093 PMCID: PMC6950077 DOI: 10.3390/ijerph16245152] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/19/2022]
Abstract
Mercury is one of the most toxic elements and causes a multitude of health problems. It is ten times more toxic to neurons than lead. This study was created to determine if mercury could be causing Alzheimer's disease (AD) by cross referencing the effects of mercury with 70 factors associated with AD. The results found that all these factors could be attributed to mercury. The hallmark changes in AD include plaques, beta amyloid protein, neurofibrillary tangles, phosphorylated tau protein, and memory loss-all changes that can be caused by mercury. Neurotransmitters such as acetylcholine, serotonin, dopamine, glutamate, and norepinephrine are inhibited in patients with Alzheimer's disease, with the same inhibition occurring in mercury toxicity. Enzyme dysfunction in patients with Alzheimer's disease include BACE 1, gamma secretase, cyclooxygenase-2, cytochrome-c-oxidase, protein kinases, monoamine oxidase, nitric oxide synthetase, acetyl choline transferase, and caspases, all which can be explained by mercury toxicity. Immune and inflammatory responses seen in patients with Alzheimer's disease also occur when cells are exposed to mercury, including complement activation, cytokine expression, production of glial fibrillary acid protein antibodies and interleukin-1, transforming growth factor, beta 2 microglobulins, and phosphodiesterase 4 stimulation. Genetic factors in patients with Alzheimer's disease are also associated with mercury. Apolipoprotein E 4 allele increases the toxicity of mercury. Mercury can inhibit DNA synthesis in the hippocampus, and has been associated with genetic mutations of presenilin 1 and 2, found in AD. The abnormalities of minerals and vitamins, specifically aluminum, calcium, copper, iron, magnesium, selenium, zinc, and vitamins B1, B12, E, and C, that occur in patients with Alzheimer's disease, also occur in mercury toxicity. Aluminum has been found to increase mercury's toxicity. Likewise, similar biochemical factors in AD are affected by mercury, including changes in blood levels of homocysteine, arachidonic acid, DHEA sulfate, glutathione, hydrogen peroxide, glycosamine glycans, acetyl-L carnitine, melatonin, and HDL. Other factors seen in Alzheimer's disease, such as increased platelet activation, poor odor identification, hypertension, depression, increased incidences of herpes virus and chlamydia infections, also occur in mercury exposure. In addition, patients diagnosed with Alzheimer's disease exhibit higher levels of brain mercury, blood mercury, and tissue mercury in some studies. The greatest exogenous sources of brain mercury come from dental amalgams. Conclusion: This review of the literature strongly suggests that mercury can be a cause of Alzheimer's Disease.
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Affiliation(s)
- Robert Siblerud
- Rocky Mountain Research Institute, 9435 Olsen Court, Wellington, CO 80549, USA
| | | | - Elaine Moore
- Memorial Hospital, Colorado Springs, CO 80549 (Retired), USA;
| | - Johannes Naumann
- European Institute for Physical Therapy and Balneology, Stadtsr 7, D-79104 Freiburg, Germany;
| | - Harald Walach
- Department of Psychology, University Witten-Herdecke, 58455 Witten, Germany;
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Bjørklund G, Hilt B, Dadar M, Lindh U, Aaseth J. Neurotoxic effects of mercury exposure in dental personnel. Basic Clin Pharmacol Toxicol 2019; 124:568-574. [PMID: 30589214 DOI: 10.1111/bcpt.13199] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 12/14/2018] [Indexed: 12/29/2022]
Abstract
Numerous studies have reported neurobehavioural effects in dental personnel occupationally exposed to chronic low levels of mercury (Hg). Hg exposure from dental work may also induce various chronic conditions such as elevation of amyloid protein expression, deterioration of microtubules and increase or inhibition of transmitter release at motor nerve terminal endings. Therefore, clinical studies of Hg toxicity in dentistry may provide new knowledge about disturbed metal homeostasis in neurodegenerative diseases such as Alzheimer's disease, multiple sclerosis and mood disorders. The purpose of this MiniReview is to evaluate the evidence of possible relevance between Hg exposure in dentistry and idiopathic disturbances in motor functions, cognitive skills and affective reactions, as well as dose-response relationships.
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Affiliation(s)
- Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway
| | - Bjørn Hilt
- Department of Occupational Medicine, St. Olav University Hospital, Trondheim, Norway.,Department of Public Health and Nursing, Norwegian University of Science and Technology, Trondheim, Norway
| | - Maryam Dadar
- Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - Ulf Lindh
- Biology Education Centre, Uppsala University, Uppsala, Sweden
| | - Jan Aaseth
- Research Department, Innlandet Hospital Trust, Brumunddal, Norway.,Faculty of Health and Social Science, Inland Norway University of Applied Sciences, Elverum, Norway
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Acute aluminum chloride toxicity revisited: Study on DNA damage and histopathological, biochemical and neurochemical alterations in rat brain. Life Sci 2018; 217:202-211. [PMID: 30528774 DOI: 10.1016/j.lfs.2018.12.009] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/30/2018] [Accepted: 12/05/2018] [Indexed: 12/22/2022]
Abstract
AIMS Due to rapid increase in industrialization in the last few years, use of aluminum (Al) and its alloys have been increased in different industrial fields. Ample evidence supports the neurotoxic effects of chronic aluminum chloride (AlCl3) administration in rats but acute Al toxicity has been less described so the present study was aimed to investigate the neurotoxic effects of acute AlCl3. MAIN METHODS To investigate such effects 12 male albino Wistar rats were randomly divided into control and test rats. AlCl3 at a dose of 150 mg/kg was intraperitoneally injected to test rats for 7 days. Rats were subjected to behavioral assessments 24 h after last dose and after behavioral assessment rats were sacrificed to collect brain samples for further neurochemical, biochemical and histopathological examinations. KEY FINDINGS In the present study acute administration of AlCl3 resulted in noticeable behavioral deficits. Cognitive deficits and neuropsychiatric disturbances were evident in AlCl3 injected rats. Test rats also exhibited marked antioxidant enzymes, cholinergic, serotonergic and dopaminergic dysfunctions and DNA fragmentation. Histopathological alterations were observed in hippocampus and cortex of rats injected with AlCl3. SIGNIFICANCE The observed effects may be due to pro-oxidant nature of Al and its participation in free radical mediated cellular injury. Al by promoting oxidative stress, impairing antioxidant defense system and altering brain neurochemistry may act as a potent neurotoxic agent as evident from observed histopathological alterations in brain of test rats. This investigation may further confirm and shed some more light on deleterious effects of acute Al intoxication on brain.
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Wang H, Liu Y, Liu G. Label-Free Biosensor Using a Silver Specific RNA-Cleaving DNAzyme Functionalized Single-Walled Carbon Nanotube for Silver Ion Determination. NANOMATERIALS 2018; 8:nano8040258. [PMID: 29677143 PMCID: PMC5923588 DOI: 10.3390/nano8040258] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 11/16/2022]
Abstract
Silver, a very common heavy metal, has been employed in electronics, medicine, jewelry, and catalysis due to its excellent chemical and physical characteristics. Silver-containing wastes can cause environmental pollution, so it is vital to monitor the Ag(I) concentration. Here, a label-free biosensor was developed for the Ag(I) detection, which used single-walled carbon nanotubes/field effect transistor (SWNTs/FET) to functionalize with a specific DNAzyme, containing an Agzyme and a complementary strand DNA (CS-DNA) embedded an RNA-base. The CS-DNA was covalently immobilized on the SWNTs’ surface through peptide bonds, and then combined with the Agzyme. When Ag(I) was bound with the Agzyme, the CS-DNA can be cleaved at the RNA site efficiently. The cleaved DNAzyme induced a remarkable change in the electrical conductivity of SWNTs. The performances of DNAzyme/SWNTs/FET were investigated using different spectroscopy and electrochemical methods. Under the optimized parameters, DNAzyme/SWNTs/FET presented a high sensitivity and selectivity towards Ag(I), in which the linear response range is 10 pM to 106 pM and the limit of detection is 5 pM(S/N = 3). Additionally, the prepared biosensor was applied to measure the Ag(I) concentration in the water sample with good results.
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Affiliation(s)
- Hui Wang
- Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education and Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture China Agricultural University, Beijing 100083, China.
| | - Yang Liu
- School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Gang Liu
- Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education and Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture China Agricultural University, Beijing 100083, China.
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Puga S, Pereira P, Pinto-Ribeiro F, O'Driscoll NJ, Mann E, Barata M, Pousão-Ferreira P, Canário J, Almeida A, Pacheco M. Unveiling the neurotoxicity of methylmercury in fish (Diplodus sargus) through a regional morphometric analysis of brain and swimming behavior assessment. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 180:320-333. [PMID: 27780124 DOI: 10.1016/j.aquatox.2016.10.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 10/11/2016] [Accepted: 10/14/2016] [Indexed: 06/06/2023]
Abstract
The current study aims to shed light on the neurotoxicity of MeHg in fish (white seabream - Diplodus sargus) by the combined assessment of: (i) MeHg toxicokinetics in the brain, (ii) brain morphometry (volume and number of neurons plus glial cells in specific brain regions) and (iii) fish swimming behavior (endpoints associated with the motor performance and the fear/anxiety-like status). Fish were surveyed for all the components after 7 (E7) and 14 (E14) days of dietary exposure to MeHg (8.7μgg-1), as well as after a post-exposure period of 28days (PE28). MeHg was accumulated in the brain of D. sargus after a short time (E7) and reached a maximum at the end of the exposure period (E14), suggesting an efficient transport of this toxicant into fish brain. Divalent inorganic Hg was also detected in fish brain along the experiment (indicating demethylation reactions), although levels were 100-200 times lower than MeHg, which pinpoints the organic counterpart as the great liable for the recorded effects. In this regard, a decreased number of cells in medial pallium and optic tectum, as well as an increased hypothalamic volume, occurred at E7. Such morphometric alterations were followed by an impairment of fish motor condition as evidenced by a decrease in the total swimming time, while the fear/anxiety-like status was not altered. Moreover, at E14 fish swam a greater distance, although no morphometric alterations were found in any of the brain areas, probably due to compensatory mechanisms. Additionally, although MeHg decreased almost two-fold in the brain during post-exposure, the levels were still high and led to a loss of cells in the optic tectum at PE28. This is an interesting result that highlights the optic tectum as particularly vulnerable to MeHg exposure in fish. Despite the morphometric alterations reported in the optic tectum at PE28, no significant changes were found in fish behavior. Globally, the effects of MeHg followed a multiphasic profile, where homeostatic mechanisms prevented circumstantially morphometric alterations in the brain and behavioral shifts. Although it has become clear the complexity of matching brain morphometric changes and behavioral shifts, motor-related alterations induced by MeHg seem to depend on a combination of disruptions in different brain regions.
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Affiliation(s)
- Sónia Puga
- Life and Health Sciences Research Institute (ICVS), School of Medicine, Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Patrícia Pereira
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Filipa Pinto-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nelson J O'Driscoll
- Department of Earth and Environmental Science, Center for Analytical Research on the Environment, K.C. Irving Center, Acadia University, Wolfville, Nova Scotia, Canada
| | - Erin Mann
- Department of Earth and Environmental Science, Center for Analytical Research on the Environment, K.C. Irving Center, Acadia University, Wolfville, Nova Scotia, Canada
| | - Marisa Barata
- IPMA - Aquaculture Research Station, 8700-005 Olhão, Portugal
| | | | - João Canário
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Armando Almeida
- Life and Health Sciences Research Institute (ICVS), School of Medicine, Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Mário Pacheco
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
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Pereira P, Puga S, Cardoso V, Pinto-Ribeiro F, Raimundo J, Barata M, Pousão-Ferreira P, Pacheco M, Almeida A. Inorganic mercury accumulation in brain following waterborne exposure elicits a deficit on the number of brain cells and impairs swimming behavior in fish (white seabream-Diplodus sargus). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 170:400-412. [PMID: 26688460 DOI: 10.1016/j.aquatox.2015.11.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 11/30/2015] [Accepted: 11/30/2015] [Indexed: 06/05/2023]
Abstract
The current study contributes to fill the knowledge gap on the neurotoxicity of inorganic mercury (iHg) in fish through the implementation of a combined evaluation of brain morphometric alterations (volume and total number of neurons plus glial cells in specific regions of the brain) and swimming behavior (endpoints related with the motor activity and mood/anxiety-like status). White seabream (Diplodus sargus) was exposed to realistic levels of iHg in water (2μgL(-1)) during 7 (E7) and 14 days (E14). After that, fish were allowed to recover for 28 days (PE28) in order to evaluate brain regeneration and reversibility of behavioral syndromes. A significant reduction in the number of cells in hypothalamus, optic tectum and cerebellum was found at E7, accompanied by relevant changes on swimming behavior. Moreover, the decrease in the number of neurons and glia in the molecular layer of the cerebellum was followed by a contraction of its volume. This is the first time that a deficit on the number of cells is reported in fish brain after iHg exposure. Interestingly, a recovery of hypothalamus and cerebellum occurred at E14, as evidenced by the identical number of cells found in exposed and control fish, and volume of cerebellum, which might be associated with an adaptive phenomenon. After 28 days post-exposure, the optic tectum continued to show a decrease in the number of cells, pointing out a higher vulnerability of this region. These morphometric alterations coincided with numerous changes on swimming behavior, related both with fish motor function and mood/anxiety-like status. Overall, current data pointed out the iHg potential to induce brain morphometric alterations, emphasizing a long-lasting neurobehavioral hazard.
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Affiliation(s)
- Patrícia Pereira
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Sónia Puga
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Vera Cardoso
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Filipa Pinto-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Joana Raimundo
- IPMA-Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal
| | - Marisa Barata
- IPMA-Aquaculture Research Station, 8700-005 Olhão, Portugal
| | | | - Mário Pacheco
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Armando Almeida
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
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Bernhoft RA. Mercury toxicity and treatment: a review of the literature. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2011; 2012:460508. [PMID: 22235210 PMCID: PMC3253456 DOI: 10.1155/2012/460508] [Citation(s) in RCA: 492] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 11/01/2011] [Indexed: 11/30/2022]
Abstract
Mercury is a toxic heavy metal which is widely dispersed in nature. Most human exposure results from fish consumption or dental amalgam. Mercury occurs in several chemical forms, with complex pharmacokinetics. Mercury is capable of inducing a wide range of clinical presentations. Diagnosis of mercury toxicity can be challenging but can be obtained with reasonable reliability. Effective therapies for clinical toxicity have been described.
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Affiliation(s)
- Robin A Bernhoft
- Bernhoft Center for Advanced Medicine, Suite 208, 11677 San Vicente Boulevard, Los Angeles, CA 90049, USA.
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Maximino C, Araujo J, Leão LKR, Grisolia ABA, Oliveira KRM, Lima MG, Batista EDJO, Crespo-López ME, Gouveia A, Herculano AM. Possible role of serotoninergic system in the neurobehavioral impairment induced by acute methylmercury exposure in zebrafish (Danio rerio). Neurotoxicol Teratol 2011; 33:727-34. [PMID: 21871955 DOI: 10.1016/j.ntt.2011.08.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 08/08/2011] [Accepted: 08/09/2011] [Indexed: 01/31/2023]
Abstract
Adult zebrafish were treated acutely with methylmercury (1.0 or 5.0 μg g(-1), i.p.) and, 24h after treatment, were tested in two behavioral models of anxiety, the novel tank and the light/dark preference tests. At the smaller dose, methylmercury produced a marked anxiogenic profile in both tests, while the greater dose produced hyperlocomotion in the novel tank test. These effects were accompanied by a decrease in extracellular levels of serotonin, and an increase in extracellular levels of tryptamine-4,5-dione, a partially oxidized metabolite of serotonin. A marked increase in the formation of malondialdehyde, a marker of oxidative stress, accompanied these parameters. It is suggested that methylmercury-induced oxidative stress produced mitochondrial dysfunction and originated tryptamine-4,5-dione, which could have further inhibited tryptophan hydroxylase. These results underscore the importance of assessing acute, low-level neurobehavioral effects of methylmercury.
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Affiliation(s)
- Caio Maximino
- Laboratório de Neuroendocrinologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Brazil.
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Mutter J. Is dental amalgam safe for humans? The opinion of the scientific committee of the European Commission. J Occup Med Toxicol 2011; 6:2. [PMID: 21232090 PMCID: PMC3025977 DOI: 10.1186/1745-6673-6-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Accepted: 01/13/2011] [Indexed: 01/06/2023] Open
Abstract
It was claimed by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)) in a report to the EU-Commission that "....no risks of adverse systemic effects exist and the current use of dental amalgam does not pose a risk of systemic disease..." [1, available from: http://ec.europa.eu/health/ph_risk/committees/04_scenihr/docs/scenihr_o_016.pdf].SCENIHR disregarded the toxicology of mercury and did not include most important scientific studies in their review. But the real scientific data show that:(a) Dental amalgam is by far the main source of human total mercury body burden. This is proven by autopsy studies which found 2-12 times more mercury in body tissues of individuals with dental amalgam. Autopsy studies are the most valuable and most important studies for examining the amalgam-caused mercury body burden.(b) These autopsy studies have shown consistently that many individuals with amalgam have toxic levels of mercury in their brains or kidneys.(c) There is no correlation between mercury levels in blood or urine, and the levels in body tissues or the severity of clinical symptoms. SCENIHR only relied on levels in urine or blood.(d) The half-life of mercury in the brain can last from several years to decades, thus mercury accumulates over time of amalgam exposure in body tissues to toxic levels. However, SCENIHR state that the half-life of mercury in the body is only "20-90 days".(e) Mercury vapor is about ten times more toxic than lead on human neurons and with synergistic toxicity to other metals.(f) Most studies cited by SCENIHR which conclude that amalgam fillings are safe have severe methodical flaws.
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Affiliation(s)
- Joachim Mutter
- Department of Environmental and integrative medicine Lohnerhofstraße 2, 78467 Constance/Germany.
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Mutter J, Naumann J, Guethlin C. Comments on the Article “The Toxicology of Mercury and Its Chemical Compounds” by Clarkson and Magos (2006). Crit Rev Toxicol 2008; 37:537-49; discussion 551-2. [PMID: 17661216 DOI: 10.1080/10408440701385770] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Clarkson and Magos (2006) provide their perspectives on the toxicology of mercury vapor and dental amalgam. As scientists who are involved in preparing a German federal guideline regarding dental amalgam, we welcome additional scientific data on this issue. However, Clarkson and Magos do not present all the relevant studies in their review. The additional data provided here show that: (a) Dental amalgam is the main source of human total mercury body burden, because individuals with amalgam have 2-12 times more mercury in their body tissues compared to individuals without amalgam; (b) there is not necessarily a correlation between mercury levels in blood, urine, or hair and in body tissues, and none of the parameters correlate with severity of symptoms; (c) the half-life of mercury deposits in brain and bone tissues could last from several years to decades, and thus mercury accumulates over time of exposure; (d) mercury, in particular mercury vapor, is known to be the most toxic nonradioactive element, and is toxic even in very low doses, and (e) some studies which conclude that amalgam fillings are safe for human beings have important methodogical flaws. Therefore, they have no value for assessing the safety of amalgam.
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Affiliation(s)
- Joachim Mutter
- University Hospital, Institute for Environmental Medicine and Hospital Epidemiology, Freiburg, Germany.
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Bellinger DC, Trachtenberg F, Zhang A, Tavares M, Daniel D, McKinlay S. Dental amalgam and psychosocial status: the New England Children's Amalgam Trial. J Dent Res 2008; 87:470-4. [PMID: 18434579 DOI: 10.1177/154405910808700504] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
High-dose exposures to elemental mercury vapor cause emotional dysfunction, but it is uncertain whether the levels of exposure that result from having dental amalgam restorations do so. As part of the New England Children's Amalgam Trial, a randomized trial involving 6- to 10-year-old children, we evaluated the hypothesis that restoration of caries using dental amalgam resulted in worse psychosocial outcomes than restoration using mercury-free composite resin. The primary outcome was the parent-completed Child Behavior Checklist. The secondary outcome was children's self-reports using the Behavior Assessment System for Children. Children's psychosocial status was evaluated in relation to three indices of mercury exposure: treatment assignment, surface-years of amalgam, and urinary mercury excretion. All significant associations favored the amalgam group. No evidence was found that exposure to mercury from dental amalgams was associated with adverse psychosocial outcomes over the five-year period following initial placement of amalgams.
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Affiliation(s)
- D C Bellinger
- Harvard Medical School, Harvard School of Public Health, Children's Hospital, Boston, MA, USA
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Mössner R, Mikova O, Koutsilieri E, Saoud M, Ehlis AC, Müller N, Fallgatter AJ, Riederer P. Consensus paper of the WFSBP Task Force on Biological Markers: biological markers in depression. World J Biol Psychiatry 2007; 8:141-74. [PMID: 17654407 DOI: 10.1080/15622970701263303] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Biological markers for depression are of great interest to aid in elucidating the causes of major depression. We assess currently available biological markers to query their validity for aiding in the diagnosis of major depression. We specifically focus on neurotrophic factors, serotonergic markers, biochemical markers, immunological markers, neuroimaging, neurophysiological findings, and neuropsychological markers. We delineate the most robust biological markers of major depression. These include decreased platelet imipramine binding, decreased 5-HT1A receptor expression, increase of soluble interleukin-2 receptor and interleukin-6 in serum, decreased brain-derived neurotrophic factor in serum, hypocholesterolemia, low blood folate levels, and impaired suppression of the dexamethasone suppression test. To date, however, none of these markers are sufficiently specific to contribute to the diagnosis of major depression. Thus, with regard to new diagnostic manuals such as DSM-V and ICD-11 which are currently assessing whether biological markers may be included in diagnostic criteria, no biological markers for major depression are currently available for inclusion in the diagnostic criteria.
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Affiliation(s)
- Rainald Mössner
- Department of Psychiatry and Psychotherapy, University of Würzburg, Würzburg, Germany
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Jones L, Bunnell J, Stillman J. A 30-year follow-up of residual effects on New Zealand School Dental Nurses, from occupational mercury exposure. Hum Exp Toxicol 2007; 26:367-74. [PMID: 17615119 DOI: 10.1177/0960327107076824] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This paper reports possible residual adverse effects from occupational mercury exposure in dentistry, Thirty years ago, the all-women exposed group worked with both silver and copper amalgam filling material without protective gloves or a ventilation system, resulting in chronic mercury exposure. The aim of the study was to test the null hypothesis in a survey of general and reproductive health, and a battery of nine neurobehavioral tests. The population was the 115 graduates of one school for dental nurses from 1968 to 1971. The sample was 43 mercury-exposed women and 32 matched controls. Statistical comparisons revealed that the two groups were equivalent on cognitive tasks and four of the six mood subscales. Significant between-group differences were found in current health symptom experience and reproductive health, especially early hysterectomy experience. Reporting of Occupational Overuse Syndrome was strongly positively correlated with years of work. In general, the study suggests that acute symptoms from mercury exposure may be reversible, while some residual health effects may be becoming more of a concern with the women's increasing age.
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Affiliation(s)
- Linda Jones
- School of Psychology, Massey University, Wellington, New Zealand.
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Zachi EC, D F V, Faria MAM, Taub A. Neuropsychological dysfunction related to earlier occupational exposure to mercury vapor. Braz J Med Biol Res 2007; 40:425-33. [PMID: 17334541 DOI: 10.1590/s0100-879x2007000300019] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Accepted: 01/19/2007] [Indexed: 11/21/2022] Open
Abstract
We assessed the neuropsychological test performances of 26 patients (mean age = 41.5 +/- 6.1 years; mean years of education = 9.8 +/- 1.8; 20 males) diagnosed with chronic occupational mercurialism who were former workers at a fluorescent lamp factory. They had been exposed to elemental mercury for an average of 10.2 +/- 3.8 years and had been away from this work for 6 +/- 4.7 years. Mean urinary mercury concentrations 1 year after cessation of work were 1.8 +/- 0.9 microg/g creatinine. Twenty control subjects matched for age, gender, and education (18 males) were used for comparison. Neuropsychological assessment included attention, inhibitory control, verbal and visual memory, verbal fluency, manual dexterity, visual-spatial function, executive function, and semantic knowledge tests. The Beck Depression Inventory and the State and Trait Inventory were used to assess depression and anxiety symptoms, respectively. The raw score for the group exposed to mercury indicated slower information processing speed, inferior performance in psychomotor speed, verbal spontaneous recall memory, and manual dexterity of the dominant hand and non-dominant hand (P < 0.05). In addition, the patients showed increased depression and anxiety symptoms (P < 0.001). A statistically significant correlation (Pearson) was demonstrable between mean urinary mercury and anxiety trait (r = 0.75, P = 0.03). The neuropsychological performances of the former workers suggest that occupational exposure to elemental mercury has long-term effects on information processing and psychomotor function, with increased depression and anxiety also possibly reflecting the psychosocial context.
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Affiliation(s)
- E C Zachi
- Instituto de Psicologia e Núcleo de Neurociências e Comportamento, Faculdade de Medicina, Universidade de São Paulo, Av. Prof. Mello Moraes 1721, 05508-900 São Paulo, SP, Brazil.
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Sammut E, Deery C, Nugent Z, Ibbetson R. A radiographic method of estimating surface area of amalgam restorations. J Dent 2006; 34:811-6. [PMID: 16687199 DOI: 10.1016/j.jdent.2006.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 03/22/2006] [Accepted: 03/30/2006] [Indexed: 11/22/2022] Open
Abstract
UNLABELLED Mercury released from the surface of amalgam fillings has been linked to a variety of disorders, but without proof of correlation. Studies use surface counts to estimate this variable, but large-scale studies would require a tool to rapidly and accurately assess restoration surface area. OBJECTIVES This study investigated digital analysis of conventional dental radiographs as a means of estimating amalgam surface area. METHODS Amalgam fillings were placed in 40 typodont teeth, the surface areas of the restorations were determined by measuring standardized photomicrographs of each surface. The teeth were radiographed, and area of the radiographic image of the restorations was measured. Data were used to produce expressions to estimate actual area from radiographic area. RESULTS Regression analyses showed that surface area estimation from radiographic area was more accurate than estimation from surface counts. The accuracy of the surface area count was further improved by combining the radiographic area with a photographic occlusal area measurement or surface count, the latter giving the highest correlation. CONCLUSIONS This study demonstrated that two-dimensional dental radiographs may be used to estimate surface area of amalgam restorations.
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Affiliation(s)
- E Sammut
- Department of Periodontology and Preventive Dentistry, Guy's King's and St Thomas's Dental Institute, Floor 21, Guy's Tower, London Bridge, UK
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Taub A, Zachi EC, Teixeira RAA, Faria MDAM, Ventura DF. A aplicação da neuropsicologia na pesquisa experimental: o exemplo da intoxicação por vapor de mercúrio. PSICOLOGIA USP 2006. [DOI: 10.1590/s0103-65642006000400015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
O desenvolvimento da neuropsicologia acompanhou a evolução do estudo do cérebro desde os registros mais antigos. A ciência neuropsicológica faz uso de medidas quantitativas de desempenho e tecnologias para produção de neuroimagem que, em conjunto, permitem a observação das relações cérebro-comportamento. No âmbito experimental, a neuropsicologia tem revelado novos conhecimentos na investigação de alterações cognitivas, psicomotoras ou comportamentais associadas a patologias congênitas ou adquiridas. No presente artigo são abordados aspectos históricos da neuropsicologia experimental e apresentados os principais resultados de um estudo referente às alterações neuropsicológicas de pacientes com histórico de intoxicação por vapor de mercúrio, presentes anos após o período de exposição ao metal.
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Mutter J, Naumann J, Sadaghiani C, Walach H, Drasch G. Amalgam studies: disregarding basic principles of mercury toxicity. Int J Hyg Environ Health 2004; 207:391-7. [PMID: 15471104 DOI: 10.1078/1438-4639-00305] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dental amalgam, which has been used for over 150 years in dental practice, consists of about 50% metallic mercury. Studies on animal and humans show that mercury is continuously released from dental amalgam and absorbed by several body tissues. It is widely accepted that the main source of mercury vapor is dental amalgam and it contributes substantially to mercury load in human body tissues. There is still a controversy about the consequences of this additional mercury exposure from amalgam to human health. Many studies were performed to evaluate possible adverse effects. In this comment, these studies were analyzed with regard to their methodical quality by considering the newest findings on mercury toxicity and metabolism. In sum, a number of studies are methodically flawed drawing inaccurate conclusions as to the safety of dental amalgam.
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Affiliation(s)
- J Mutter
- Institute for Environmental Medicine and Hospital Epidemiology, University Hospital, Freiburg, Germany.
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Mutter J, Daschner FD. Commentary regarding the article by Gottwald et al.: "Amalgam disease"--poisoning, allergy, or psychic disorder? Int. J. Hyg. Environ. Health 204, 223-229 (2001). Int J Hyg Environ Health 2003; 206:69-70; author reply 71-3. [PMID: 12621906 DOI: 10.1078/1438-4639-00185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Pizzichini M, Fonzi M, Sugherini L, Fonzi L, Gasparoni A, Comporti M, Pompella A. Release of mercury from dental amalgam and its influence on salivary antioxidant activity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2002; 284:19-25. [PMID: 11846163 DOI: 10.1016/s0048-9697(01)00853-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Dental amalgam fillings are known to release significant amounts of mercury (Hg) in saliva which could represent a continuous source of oxidative damage to mouth tissues. The present investigation was aimed at verifying this hypothesis by determining a possible correlation between salivary Hg levels and salivary total antioxidant activity (TAA), which is used as an index of oxidative stress. Samples of saliva from 34 healthy donors were analyzed for Hg content, by vapor atomic absorption spectrometry, and for TAA, by determining the ferric reducing ability ('FRAP' method). A significant correlation between Hg and the number of amalgam restorations or total amalgam surface was evident in both the male and female subjects. A significant negative correlation between TAA and Hg levels or number of amalgam restorations or amalgam surface was evident in females, indicating that small increases in salivary Hg were sufficient to produce a decrease in salivary TAA. On the other hand, no significant correlation was found in the males. The present study provides, for the first time, evidence of a pro-oxidant role of the amalgam Hg chronically released in saliva.
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Affiliation(s)
- M Pizzichini
- Department of Biomedical Sciences, University of Siena, Italy
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Saxe SR, Wekstein MW, Kryscio RJ, Henry RG, Cornett CR, Snowdon DA, Grant FT, Schmitt FA, Donegan SJ, Wekstein DR, Ehmann WD, Markesbery WR. Alzheimer's disease, dental amalgam and mercury. J Am Dent Assoc 1999; 130:191-9. [PMID: 10036842 DOI: 10.14219/jada.archive.1999.0168] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Mercury, or Hg, is a neurotoxin that has been speculated to play a role in the pathogenesis of Alzheimer's disease, or AD. Dental amalgam releases low levels of Hg vapor and is a potential source of Hg for a large segment of the adult population. METHODS The authors studied 68 subjects with AD and 33 control subjects without AD to determine Hg levels in multiple brain regions at autopsy and to ascertain the subjects' dental amalgam status and history. The subjects were from central Kentucky and Elm Grove, Wis. The authors conducted dental amalgam assessments during the lives of the majority of subjects and in some subjects at the time of autopsy only. The authors also determined three dental amalgam index scores--Event (placement, repair or removal of amalgam), Location and Time In Mouth--in addition to the numbers of and surface area of occlusal amalgam restorations. The authors determined Hg levels in multiple brain regions and performed full neuropathologic evaluations to confirm the normal status of the brain or the presence of AD. RESULTS The authors found no significant association of AD with the number, surface area or history of having dental amalgam restorations. They also found no statistically significant differences in brain Hg level between subjects with AD and control subjects. CONCLUSIONS Hg in dental amalgam restorations does not appear to be a neurotoxic factor in the pathogenesis of AD. The authors found that brain Hg levels are not associated with dental amalgam, either from existing amalgam restorations or according to subjects' dental amalgam restoration history. CLINICAL IMPLICATIONS Dental amalgam restorations, regardless of number, occlusal surface area or time, do not relate to brain Hg levels.
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Affiliation(s)
- S R Saxe
- Geriatric Oral Health Program, College of Dentistry, University of Kentucky, Lexington, USA
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Grandjean P, Guldager B, Larsen IB, Jørgensen PJ, Holmstrup P. Placebo response in environmental disease. Chelation therapy of patients with symptoms attributed to amalgam fillings. J Occup Environ Med 1997; 39:707-14. [PMID: 9273873 DOI: 10.1097/00043764-199708000-00004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Treatment of patients who attribute their environmental illness to mercury from amalgam fillings is largely experimental. On the Symptom Check List, overall distress, and somatization, obsessive-compulsive, depression, and anxiety symptom dimensions, were increased in 50 consecutive patients examined, and Eysenck Personality Questionnaire scores suggested less extroversion and increased degree of emotional liability. Succimer (meso-2, 3-dimercaptosuccinic acid) was given at a daily dose of 30 mg/kg for five days in a double-blind, randomized placebo-controlled trial. Urinary excretion of mercury and lead was considerably increased in the patients who received the chelator. Immediately after the treatment and 5 to 6 weeks later, most distress dimensions had improved considerably, but there was no difference between the succimer and placebo groups. These findings suggest that some patients with environmental illness may substantially benefit from placebo.
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Affiliation(s)
- P Grandjean
- Department of Environmental Medicine, Odense University, Denmark
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Bratel J, Haraldson T, Ottosson JO. Potential side effects of dental amalgam restorations. (II). No relation between mercury levels in the body and mental disorders. Eur J Oral Sci 1997; 105:244-50. [PMID: 9249191 DOI: 10.1111/j.1600-0722.1997.tb00207.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A group of 50 consecutive patients, referred for self-reported complaints which they related to dental amalgam restorations, was compared with control patients matched by age, sex and postal zip code. All patients were subjected to a psychiatric examination and a set of rating scales and questionnaires, and the symptoms were related to the mercury levels in blood, urine and hair. A psychiatric diagnosis was established in 70% of the patients in the index group versus 14% in the control group. The prevailing symptoms were anxiety, asthenia and depression. Mercury levels in blood, urine and hair were similar among index cases and controls, and were far below critical levels of mercury intoxication. There was no correlation between mercury levels and the severity of the reported symptoms. Therefore, mercury was not a likely cause of the complaints. Instead, the reported symptoms were part of a broad spectrum of mental disorders.
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Affiliation(s)
- J Bratel
- Department of Endodontology/Oral Diagnosis, Faculty of Odontology, Göteborg University, Sweden.
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