1
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Geier DA, Geier MR. Dental amalgam fillings and mercury vapor safety limits in American adults. Hum Exp Toxicol 2022; 41:9603271221106341. [DOI: 10.1177/09603271221106341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective For more than 150 years, dental amalgam fillings (50% metallic mercury (Hg0) by weight) have been used in American dentistry. The US Food and Drug Administration (FDA) acknowledged that amalgams release Hg vapor that may be harmful to certain patients. This study examined the impact of Hg vapor exposure from amalgams in American adults. Methods Amalgam-Hg vapor exposure among 158,274,824 weighted-adult Americans was examined in the 2015–2018 National Health and Nutrition Examination Survey (NHANES). Beta (β)-coefficients were calculated for the correlation between the number of amalgam surfaces and daily micrograms (μg) of urinary Hg and daily μg of Hg vapor exposure from amalgams per kilogram (Kg) bodyweight. Results About 91 million (57.8%) adults had ≥1 amalgam surface and about 67 million (42.2%) had no amalgams. A β-coefficient = 0.041 significantly correlated the number of amalgam surfaces to daily amounts of urinary Hg. Differences were observed for gender and racial groups. Daily Hg vapor doses from amalgams were in excess of the most restrictive California’s Environmental Protection Agency (EPA) safety limit for about 86 million (54.3%) adults and in excess of the least restrictive US EPA safety limit among about 16 million (10.4%) adults. The mean allowable number of amalgam surfaces ranged from 1.28 for adult females under the California’s EPA safety limit to 16.23 for adult males under the US EPA safety limit. Conclusion Given that American adults are receiving significant, ongoing exposure to Hg vapor from amalgams, careful evaluation of the need to reduce use of amalgams should be considered.
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Affiliation(s)
- DA Geier
- Research Department, Institute of Chronic Illnesses, Silver Spring, MD, USA
| | - MR Geier
- Research Department, Institute of Chronic Illnesses, Silver Spring, MD, USA
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2
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Bartel-Steinbach M, Lermen D, Gwinner F, Schäfer M, Göen T, Conrad A, Weber T, von Briesen H, Kolossa-Gehring M. Long-term monitoring of mercury in young German adults: Time trend analyses from the German Environmental Specimen Bank, 1995-2018. ENVIRONMENTAL RESEARCH 2022; 207:112592. [PMID: 34973943 DOI: 10.1016/j.envres.2021.112592] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
As highlighted in the Minamata Convention, Mercury (Hg) in its various forms poses a substantial risk to human health and the environment. The health relevance of Hg is also recognized by the European Human Biomonitoring Initiative (HBM4EU), which classifies Hg as a priority substance, since considerable knowledge and data gaps on Hg exposure levels and their changes over time still exist in Europe. The German Environmental Specimen Bank (German ESB) provides valuable policy relevant data and long-term trends of substance exposure on a national level for international comparison and evaluation. In this study we analysed data of the German ESB on Hg exposure of young adults aged 20 to 29 including data on urinary Hg levels from 1995 to 2018 and whole blood Hg levels from 2001 to 2010. Results show a clear decrease in both, about 86% in urine total daily Hg excretion from 1995 (0.76 μg/L) to 2018 (0.11 μg/L) (n = 10,069) and about 57% in blood concentrations of Hg from 2001 (1.76 μg/L) to 2010 (0.77 μg/L) (n = 4085). Over the investigated timeframe only a few values exceeded the toxicologically derived health based guidance value HBM I for blood and urine, with these exceedances decreasing over time in line with the general trend. The factors mostly influencing Hg excretion identified in this study are dental amalgam as well as fish and seafood consumption. Besides other factors (e.g. age and sex), also airborne Hg exposure appears to be a low but evident influencing factor in Germany. Although a considerable decrease in internal Hg exposure is recognized in the last decades, the current low-level exposure may cause adverse health effects especially to vulnerable groups such as pregnant women and children. To further elucidate and evaluate current exposure sources and to reduce human exposure to Hg, continuous environmental and human biomonitoring is needed.
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Affiliation(s)
| | - Dominik Lermen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Frederik Gwinner
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
| | - Moritz Schäfer
- Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas Göen
- Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - André Conrad
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Till Weber
- German Environment Agency (Umweltbundesamt), Berlin, Germany
| | - Hagen von Briesen
- Fraunhofer Institute for Biomedical Engineering IBMT, Sulzbach, Germany
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3
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A carbon-based fluorescent probe (N-CDs) encapsulated in a zeolite matrix (NaFZ) for ultrasensitive detection of Hg (II) in fish. Talanta 2021; 234:122646. [PMID: 34364455 DOI: 10.1016/j.talanta.2021.122646] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 11/23/2022]
Abstract
In this work, a novel strategy was addressed to fabricate new sensing probe (N-CDs@NaFZ) from nitrogen doped carbon dots (N-CDs) confined in Al-free ferrisilicates zeolite (NaFZ) by hydrothermal/solvothermal method. The probe was systematically characterized by HR-TEM, FTIR, energy dispersive X-ray (EDX), powder X-ray diffraction, and UV-Vis absorption and fluorescence spectrophotometers. Characterization of the designed nanocomposite template N-CDs@NaFZ by fluorescence spectrum demonstrates a variety of important conducts as stability improvements, reasonable dispersibility in water, highly emission intensity enhancement at 435 nm when excited at 340 nm, excitation independent fluorescence behaviors, great quantum yield percentage of 91.2%, and narrow size distribution 12 nm, as a nano-space confinement effect of zeolite effectively increase the rigidity of N-CDs. Based on the fluorescence quenching mechanism, the designed approach exhibits an excellent selectivity and good sensitive response to the presence of Hg(II) ions under ambient temperature, with a wide linear range of 0.1-1500 nM and lower detection limits of 5.5 pM. Influences of variables pH and incubation time were optimized. The N-CDs@NaFZ sensor was effectively applied for the detection of Hg(II) ions in the farmed and wild rainbow trout fishes, and the results are in reasonable agreement when compared with that obtained by the cold vapor atomic absorption method.
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4
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Yin L, Lin S, Summers AO, Roper V, Campen MJ, Yu X. Children with Amalgam Dental Restorations Have Significantly Elevated Blood and Urine Mercury Levels. Toxicol Sci 2021; 184:104-126. [PMID: 34453845 DOI: 10.1093/toxsci/kfab108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Human exposure to organic mercury (Hg) as methylmercury (MeHg) from seafood consumption is widely considered a health risk because pure methylmercury is extremely neurotoxic. In contrast, the clinical significance of Hg exposure from amalgam (AMG) dental restorations, the only other major nonoccupational source of Hg exposure, has long been debated. Here, we examined data from the two most recent National Health and Nutrition Examination Surveys (NHANES) on 14 181 subjects to assess the contributions of seafood consumption versus AMG to blood total mercury (THg), inorganic mercury (IHg), and methyl mercury (MeHg) and to urine creatinine corrected mercury (UTHg). All subjects were also classified as to their self-reported qualitative consumption of seafood (59% fish and 44% shellfish). Subjects with restorations were grouped into three groups (0) those without AMG (64.4%), (1) those with 1-5 dental AMG restorations (19.7%), (2) those with more than five AMG (16%). Seafood consumption increased total mercury in urine (UTHg) and total mercury (THg) and methyl mercury (MeHg) in blood, but unlike AMG, seafood did not increase blood inorganic mercury (IHg). Using stratified covariate (ANOVA) and multivariate (GLM) analyses revealed a strong correlation of blood (THg and IHg) and urine (UTHg) levels with the number of AMGs. In a subpopulation without fish consumption, having more than five AMG restorations raised blood THg (103%), IHg (221%), and urine UTHg (221%) over the group without AMG. The most striking difference was noted in classification by age: subjects under 6 years old with more than five AMG restorations had the highest blood IHg and urine UTHg among all age groups. Elevation of bivalent IHg on a large scale in children warrants urgent in-depth risk assessment with specific attention to genetic- and gender-associated vulnerabilities.
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Affiliation(s)
- Lei Yin
- Reprotox Biotech, Science & Technology Park, University of New Mexico, Albuquerque, NM, USA
| | - Simon Lin
- The Center for Pediatric Dentistry, University of Washington, WA, USA
| | - Anne O Summers
- Department of Microbiology, University of Georgia, Athens, GA, USA
| | - Van Roper
- College of Nursing, University of New Mexico, Albuquerque, NM, USA
| | - Matthew J Campen
- College of Pharmacy, University of New Mexico College of Nursing, NM, USA
| | - Xiaozhong Yu
- College of Nursing, University of New Mexico, Albuquerque, NM, USA
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5
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Branco V, Aschner M, Carvalho C. Neurotoxicity of mercury: an old issue with contemporary significance. ADVANCES IN NEUROTOXICOLOGY 2021; 5:239-262. [PMID: 34263092 PMCID: PMC8276940 DOI: 10.1016/bs.ant.2021.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Mercury exerts a variety of toxic effects, depending on the specific compound and route of exposure. However, neurotoxicity in virtue of its consequence to health causes the greatest concern for toxicologists. This is particularly true regarding fetal development, where neurotoxic effects are much more severe than in adults, and the toxicity threshold is lower. Here, we review the major concepts regarding the neurotoxicity of mercury compounds (mercury vapor; methylmercury and ethylmercury), from exposure routes to toxicokinetic particularities leading to brain deposition and the development of neurotoxic effects. Albeit research on the neurotoxicity of mercury compounds has significantly advanced from the second half of the twentieth century onwards, several grey areas regarding the mechanism of toxicity still exist. Thus, we emphasize research advances during the last two decades concerning the molecular interactions of mercury which cause neurotoxic effects. Highlights include the disruption of glutamate signaling and excitotoxicity resulting from exposure to mercury and the interaction with redox active residues such as cysteines and selenocysteines which are the premise accounting for the disruption of redox homeostasis caused by mercurials. We also address how immunotoxic effects at the CNS, namely microglia and astrocyte activation modulate developmental neurotoxicity, a major topic in contemporary research.
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Affiliation(s)
- Vasco Branco
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, USA
| | - Cristina Carvalho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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6
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Sekovanić A, Piasek M, Orct T, Sulimanec Grgec A, Matek Sarić M, Stasenko S, Jurasović J. Mercury Exposure Assessment in Mother-Infant Pairs from Continental and Coastal Croatia. Biomolecules 2020; 10:biom10060821. [PMID: 32471193 PMCID: PMC7355586 DOI: 10.3390/biom10060821] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/31/2022] Open
Abstract
The main source of mercury (Hg) exposure in the general population is fish. Another possible source is dental amalgam. Here, we compare the levels of Hg and selenium (Se) in samples of maternal and fetal origin collected shortly after childbirth of healthy postpartum women in the coastal (n = 96) and continental (n = 185) areas of Croatia related to maternal seafood/fish consumption. We also evaluated Hg concentrations and maternal serum metallothionein (MT2) concentrations in relation to the number of dental amalgam fillings, and MT2A-5A/G (rs28366003) polymorphism. The levels of Hg and Se in maternal hair and blood/serum, placenta and cord blood/serum increased in relation to increasing fish consumption with the highest values in subjects from the coast. The concentrations of each element and between elements correlated across the matrices. Increasing amalgam number correlated linearly with increased Hg levels in maternal and cord serum and was not associated with serum MT2. No association of MT2A-5A/G polymorphism and Hg or Se levels were found. The results confirmed higher fish consumption in coastal vs. continental Croatia and increases of both Hg and Se related to fish consumption in all analyzed samples. Increased blood Hg reflected the predominant MeHg share from seafood, while increased serum Hg matched exposure from dental amalgams.
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Affiliation(s)
- Ankica Sekovanić
- Institute for Medical Research and Occupational Health, 10000 Zagreb, Croatia; (A.S.); (T.O.); (A.S.G.); (J.J.)
| | - Martina Piasek
- Institute for Medical Research and Occupational Health, 10000 Zagreb, Croatia; (A.S.); (T.O.); (A.S.G.); (J.J.)
- Correspondence:
| | - Tatjana Orct
- Institute for Medical Research and Occupational Health, 10000 Zagreb, Croatia; (A.S.); (T.O.); (A.S.G.); (J.J.)
| | - Antonija Sulimanec Grgec
- Institute for Medical Research and Occupational Health, 10000 Zagreb, Croatia; (A.S.); (T.O.); (A.S.G.); (J.J.)
| | | | - Sandra Stasenko
- Clinical Department of Obstetrics and Gynecology, Merkur University Hospital, 10000 Zagreb, Croatia;
| | - Jasna Jurasović
- Institute for Medical Research and Occupational Health, 10000 Zagreb, Croatia; (A.S.); (T.O.); (A.S.G.); (J.J.)
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7
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Ajiboye AS, Mossey PA, Fox CH. International Association for Dental Research Policy and Position Statements on the Safety of Dental Amalgam. J Dent Res 2020; 99:763-768. [PMID: 32315245 DOI: 10.1177/0022034520915878] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- A S Ajiboye
- International Association for Dental Research, Alexandria, VA, USA
| | - P A Mossey
- Department of Orthodontics, University of Dundee, Dundee, UK
| | | | - C H Fox
- International Association for Dental Research, Alexandria, VA, USA
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8
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The current environmental levels of endocrine disruptors (mercury, cadmium, organochlorine pesticides and PCBs) in a Belgian adult population and their predictors of exposure. Int J Hyg Environ Health 2018; 221:211-222. [DOI: 10.1016/j.ijheh.2017.10.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 10/16/2017] [Accepted: 10/24/2017] [Indexed: 12/27/2022]
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9
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Li Y, Liu N, Liu H, Wang Y, Hao Y, Ma X, Li X, Huo Y, Lu J, Tang S, Wang C, Zhang Y, Gao Z. A novel label-free fluorescence assay for one-step sensitive detection of Hg 2+ in environmental drinking water samples. Sci Rep 2017; 7:45974. [PMID: 28378768 PMCID: PMC5380999 DOI: 10.1038/srep45974] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/07/2017] [Indexed: 01/11/2023] Open
Abstract
A novel label-free fluorescence assay for detection of Hg2+ was developed based on the Hg2+-binding single-stranded DNA (ssDNA) and SYBR Green I (SG I). Differences from other assays, the designed rich-thymine (T) ssDNA probe without fluorescent labelling can be rapidly formed a T-Hg2+-T complex and folded into a stable hairpin structure in the presence of Hg2+ in environmental drinking water samples by facilitating fluorescence increase through intercalating with SG I in one-step. In the assay, the fluorescence signal can be directly obtained without additional incubation within 1 min. The dynamic quantitative working ranges was 5–1000 nM, the determination coefficients were satisfied by optimization of the reaction conditions. The lowest detection limit of Hg2+ was 3 nM which is well below the standard of U.S. Environmental Protection Agency. This method was highly specific for detecting of Hg2+ without being affected by other possible interfering ions from different background compositions of water samples. The recoveries of Hg2+ spiked in these samples were 95.05–103.51%. The proposed method is more viable, low-costing and simple for operation in field detection than the other methods with great potentials, such as emergency disposal, environmental monitoring, surveillance and supporting of ecological risk assessment and management.
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Affiliation(s)
- Ya Li
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China.,Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
| | - Nan Liu
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China.,Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China.,School of Public Health, State Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong, 510080, P. R. China.,Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Hui Liu
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China
| | - Yu Wang
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China
| | - Yuwei Hao
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China
| | - Xinhua Ma
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
| | - Xiaoli Li
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
| | - Yapeng Huo
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
| | - Jiahai Lu
- School of Public Health, State Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong, 510080, P. R. China
| | - Shuge Tang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China.,Department of Nutrition and Food Hygiene, College of Public Health, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Caiqin Wang
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China.,Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
| | - Yinhong Zhang
- School of Public Health, Lanzhou University, Lanzhou 73000, P. R. China
| | - Zhixian Gao
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Health and Environmental Medicine, Tianjin, 300050, P. R. China
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10
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Kobal AB, Snoj Tratnik J, Mazej D, Fajon V, Gibičar D, Miklavčič A, Kocman D, Kotnik J, Sešek Briški A, Osredkar J, Krsnik M, Prezelj M, Knap Č, Križaj B, Liang L, Horvat M. Exposure to mercury in susceptible population groups living in the former mercury mining town of Idrija, Slovenia. ENVIRONMENTAL RESEARCH 2017; 152:434-445. [PMID: 27488273 DOI: 10.1016/j.envres.2016.06.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 06/21/2016] [Accepted: 06/22/2016] [Indexed: 06/06/2023]
Abstract
500 years of mercury (Hg) mining in the town of Idrija has caused severe pollution in Idrija and its surroundings. Following the closure of the mine in 1995, the environment remains contaminated with Hg. Sources of elemental-, inorganic- and methyl Hg exposure were identified, potential environmental level of exposure to Hg was evaluated and actual internal exposure to Hg was assessed in selected susceptible population groups comprising school-age children and pregnant women living in Idrija and in control groups from rural and urban environments. The study of pregnant women (n=31) was conducted between 2003 and 2008, and the study of school-age children (n=176) in 2008. Potential interaction of Hg with selenium (Se) in plasma was assessed in both study populations, while in pregnant women antioxidative enzyme activity (glutathione peroxidase, superoxide dismutase and catalase) in erythrocytes of maternal and cord blood was also assessed. Actual exposure to Hg as indicated by levels of Hg in children's blood (geometric mean (GM) 0.92µg/L), mother's blood (GM 1.86µg/L), children's urine (GM 1.08µg/g crea.), mother's urine (GM 2.51µg/L), children's hair (GM 241ng/g) and mother's hair (GM 251ng/g) was higher in the two study groups from Idrija than in the control groups from rural areas, but was still at the level of a "normal" population and reflects mainly exposure to elemental Hg (Hg°) from dental amalgam and, to a certain extent atmospheric Hg°. Furthermore, the internal doses of Hg received during pregnancy did not decrease the bioavailability of Se. Based on observation in children, the increase in Se protein expression is suggested to be a consequence of moderately elevated exposure to Hg°. The observed changes in activity of antioxidative enzymes, as biomarkers of oxidative stress, appear to be mainly associated with pregnancy per se and not with an increased exposure to Hg. In view of the continuing increased potential for Hg exposure and the low number of pregnant women studied, the results warrant a further longitudinal study of a larger group of pregnant women residing in the area of the former mercury mine.
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Affiliation(s)
- Alfred B Kobal
- Ex-Department of Occupational Health, Idrija Mercury Mine, Arkova 43, 5280 Idrija, Slovenia
| | - Janja Snoj Tratnik
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia; 'Jožef Stefan' International Postgraduate School, Ljubljana, Slovenia
| | - Darja Mazej
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Vesna Fajon
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Darija Gibičar
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Ana Miklavčič
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - David Kocman
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Jože Kotnik
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Alenka Sešek Briški
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia
| | - Joško Osredkar
- University Medical Centre Ljubljana, Institute for Clinical Chemistry and Biochemistry, University in Ljubljana, Slovenia
| | - Mladen Krsnik
- University Medical Centre Ljubljana, Institute for Clinical Chemistry and Biochemistry, University in Ljubljana, Slovenia
| | - Marija Prezelj
- University Medical Centre Ljubljana, Institute for Clinical Chemistry and Biochemistry, University in Ljubljana, Slovenia
| | - Črtomir Knap
- Department of Gynecology, Idrija Health Service, Otona Župančiča 3, 5280 Idrija, Slovenia
| | - Bojana Križaj
- Laboratory Department, Idrija Health Service, Otona Župančiča 3, 5280 Idrija, Slovenia
| | - Lian Liang
- Cebam Analytical, Inc., 18804 North Creek Parkway, Bothell, WA 98011, USA
| | - Milena Horvat
- 'Jožef Stefan' Institute, Department of Environmental Sciences, Ljubljana, Slovenia; 'Jožef Stefan' International Postgraduate School, Ljubljana, Slovenia.
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11
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Yin L, Yu K, Lin S, Song X, Yu X. Associations of blood mercury, inorganic mercury, methyl mercury and bisphenol A with dental surface restorations in the U.S. population, NHANES 2003-2004 and 2010-2012. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016; 134P1:213-225. [PMID: 27639196 DOI: 10.1016/j.ecoenv.2016.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 05/09/2023]
Abstract
The potential adverse health effects of mercury from amalgam and bisphenol A (BPA) from composite resin have been significant concerns. It is unclear whether dental restorative materials significantly contribute to mercury or BPA levels. The purpose of this study is to use NHANES data including 14,703 subjects (2003-2004: n=7514; 2011-2012: n=7189) to examine the association between Dental Surface Restorations (DSR) and blood total mercury (THg), inorganic mercury (IHg), methyl mercury (MeHg) and urinary BPA through the stratification of covariates and multivariate analysis. Subjects were divided into three groups based on the number of dental surface restorations (DSRs, 0, 1-8, >8). Blood THg and IHg in 2003-2004 were significantly higher in the subjects with DSR (geometric mean of 0.48, 0.69 and 1.17μg/l for THg; 0.32, 0.33 and 0.39μg/l for IHg with DSR 0, 1-8 and >8). Similarly, increases of THg, IHg and MeHg were also observed in 2013-2014 (geometric mean of 0.51, 0.69 and 0.99μg/l for THg; 0.40, 0.49 and 0.66μg/l for MeHg; 0.20, 0.22 and 0.29μg/l for IHg with DSR 0, 1-8 and >8). Linear regression model analysis revealed blood THg and IHg in 2003-2004 and THg, IHg and MeHg in 2011-2012 were quantitatively associated with the number of DSRs. A dramatic decrease in urinary BPA from 2003 to 2004-2011-2012 was observed, but no significant increase with DSRs in either period of study. In conclusion, significant increases in blood THg, IHg, and MeHg in the subjects with DSRs are confirmed in a nationally representative population, a critical step in assessing the potential risk of adverse effects from dental restorative materials, but no association between dental fillings and urinary BPA was found.
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Affiliation(s)
- Lei Yin
- Department of Environmental Health Science, University of Georgia, Athens, GA, USA
| | - Kevin Yu
- Department of Environmental Health Science, University of Georgia, Athens, GA, USA
| | - Simon Lin
- The Center for Pediatric Dentistry, University of Washington, USA
| | - Xiao Song
- Department of Epidemiology and Biostatistics, University of Georgia, Athens, GA, USA
| | - Xiaozhong Yu
- Department of Environmental Health Science, University of Georgia, Athens, GA, USA.
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12
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Parajuli RP, Goodrich JM, Chou HN, Gruninger SE, Dolinoy DC, Franzblau A, Basu N. Genetic polymorphisms are associated with hair, blood, and urine mercury levels in the American Dental Association (ADA) study participants. ENVIRONMENTAL RESEARCH 2016; 149:247-258. [PMID: 26673400 PMCID: PMC4897752 DOI: 10.1016/j.envres.2015.11.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 11/25/2015] [Accepted: 11/26/2015] [Indexed: 05/21/2023]
Abstract
BACKGROUND/AIMS Mercury (Hg) is a potent toxicant of concern to the general public. Recent studies suggest that several genes that mediate Hg metabolism are polymorphic. We hypothesize that single nucleotide polymorphisms (SNPs) in such genes may underline inter-individual differences in exposure biomarker concentrations. METHODS Dental professionals were recruited during the American Dental Association (ADA) 2012 Annual Meeting. Samples of hair, blood, and urine were collected for quantifying Hg levels and genotyping (88 SNPs in classes relevant to Hg toxicokinetics including glutathione metabolism, selenoproteins, metallothioneins, and xenobiotic transporters). Questionnaires were administrated to obtain information on demographics and sources of Hg exposure (e.g., fish consumption and use of dental amalgam). Here, we report results for 380 participants with complete genotype and Hg biomarker datasets. ANOVA and linear regressions were used for statistical analysis. RESULTS Mean (geometric) Hg levels in hair (hHg), blood (bHg), urine (uHg), and the average estimated Hg intake from fish were 0.62µg/g, 3.75µg/L, 1.32µg/L, and 0.12µg/kg body weight/day, respectively. Out of 88 SNPs successfully genotyped, Hg biomarker levels differed by genotype for 25 SNPs, one of which remained significant following Bonferroni correction in ANOVA. When the associations between sources of Hg exposure and SNPs were analyzed with respect to Hg biomarker concentrations, 38 SNPs had significant main effects and/or gene-Hg exposure source interactions. Twenty-five, 23, and four SNPs showed significant main effects and/or interactions for hHg, bHg, and uHg levels, respectively (p<0.05), and six SNPs (in GCLC, MT1M, MT4, ATP7B, and BDNF) remained significant following Bonferroni correction. CONCLUSION The findings suggest that polymorphisms in environmentally-responsive genes can influence Hg biomarker levels. Hence, consideration of such gene-environment factors may improve the ability to assess the health risks of Hg more precisely.
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Affiliation(s)
- Rajendra Prasad Parajuli
- Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Quebec, Canada.
| | - Jaclyn M Goodrich
- Department of Environmental Health Sciences, Unisiversity of Michigan School of Public Health, Ann Arbor, MI, USA.
| | | | | | - Dana C Dolinoy
- Department of Environmental Health Sciences, Unisiversity of Michigan School of Public Health, Ann Arbor, MI, USA; Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA.
| | - Alfred Franzblau
- Department of Environmental Health Sciences, Unisiversity of Michigan School of Public Health, Ann Arbor, MI, USA.
| | - Niladri Basu
- Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, Quebec, Canada; Department of Environmental Health Sciences, Unisiversity of Michigan School of Public Health, Ann Arbor, MI, USA.
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Al-Saleh I, Elkhatib R, Al-Rouqi R, Abduljabbar M, Eltabache C, Al-Rajudi T, Nester M. Alterations in biochemical markers due to mercury (Hg) exposure and its influence on infant's neurodevelopment. Int J Hyg Environ Health 2016; 219:898-914. [PMID: 27453562 DOI: 10.1016/j.ijheh.2016.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/26/2016] [Accepted: 07/01/2016] [Indexed: 01/04/2023]
Abstract
This study examined the role of oxidative stress due to mercury (Hg) exposure on infant's neurodevelopmental performance. A total of 944 healthy Saudi mothers and their respective infants (aged 3-12 months) were recruited from 57 Primary Health Care Centers in Riyadh City. Total mercury (Hg) was measured in mothers and infants urine and hair samples, as well as mother's blood and breast milk. Methylmercury (MeHg) was determined in the mothers and infants' hair and mother's blood. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and porphyrins were used to assess oxidative stress. The infant's neurodevelopment was evaluated using Denver Developmental Screening Test II (DDST-II) and Parents' Evaluation of Developmental Status. The median total Hg levels in mother's urine, infant's urine, mother's hair, infant's hair, and mother's blood and breast milk were 0.995μg/l, 0.716μg/l, 0.118μg/g dw, 0.101μg/g dw, 0.635μg/l, and 0.884μg/l respectively. The median MeHg levels in mother's hair, infant's hair, and mother's blood were 0.132μg/g dw, 0.091μg/g dw, and 2.341μg/l respectively. A significant interrelationship between mothers and infants Hg measures in various matrices was noted. This suggests that mother's exposure to different forms of Hg (total and/or MeHg) from various sources contributed significantly to the metal body burden of their respective infants. Even though Hg exposure was low, it induced high oxidative stress in mothers and infants. The influence of multiplicative interaction terms between Hg measures and oxidative stress biomarkers was tested using multiple regression analysis. Significant interactions between the urinary Hg levels in mothers and infants and oxidative stress biomarkers (8-OHdG and MDA) were noted. The MeHg levels in mother-infant hair revealed similar interaction patterns. The p-values for both were below 0.001. These observations suggest that the exposure of our infants to Hg via mothers either during pregnancy and/or neonatal life, promoted oxidative stress that might have played a role in infant neurodevelopmental delays that we reported previously. The results confirmed that the interaction between infant's MeHg in hair and 8-OHdG and MDA levels was significantly associated with a delay in DDST-II performance (ß=-0.188, p=0.028). This finding provides an insight into the potential consequences of Hg-induced oxidative stress to infant's cognitive neurodevelopment for the first time. This observation still needs future studies to be validated. Given the low MeHg levels in our population, these findings are of particular importance.
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Affiliation(s)
- Iman Al-Saleh
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia.
| | - Rola Elkhatib
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
| | - Reem Al-Rouqi
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
| | - Mai Abduljabbar
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
| | - Chafica Eltabache
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
| | - Tahreer Al-Rajudi
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
| | - Michael Nester
- Department of Neurosciences, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211, Saudi Arabia
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Park C, Hwang M, Kim H, Ryu S, Lee K, Choi K, Paek D. Early snapshot on exposure to environmental chemicals among Korean adults—results of the first Korean National Environmental Health Survey (2009–2011). Int J Hyg Environ Health 2016; 219:398-404. [DOI: 10.1016/j.ijheh.2016.04.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 03/28/2016] [Accepted: 04/03/2016] [Indexed: 01/10/2023]
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Nagpal N, Bettiol SS, Isham A, Hoang H, Crocombe LA. A Review of Mercury Exposure and Health of Dental Personnel. Saf Health Work 2016; 8:1-10. [PMID: 28344835 PMCID: PMC5355537 DOI: 10.1016/j.shaw.2016.05.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 05/18/2016] [Accepted: 05/30/2016] [Indexed: 11/02/2022] Open
Abstract
Considerable effort has been made to address the issue of occupational health and environmental exposure to mercury. This review reports on the current literature of mercury exposure and health impacts on dental personnel. Citations were searched using four comprehensive electronic databases for articles published between 2002 and 2015. All original articles that evaluated an association between the use of dental amalgam and occupational mercury exposure in dental personnel were included. Fifteen publications from nine different countries met the selection criteria. The design and quality of the studies showed significant variation, particularly in the choice of biomarkers as an indicator of mercury exposure. In several countries, dental personnel had higher mercury levels in biological fluids and tissues than in control groups; some work practices increased mercury exposure but the exposure levels remained below recommended guidelines. Dental personnel reported more health conditions, often involving the central nervous system, than the control groups. Clinical symptoms reported by dental professionals may be associated with low-level, long-term exposure to occupational mercury, but may also be due to the effects of aging, occupational overuse, and stress. It is important that dental personnel, researchers, and educators continue to encourage and monitor good work practices by dental professionals.
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Affiliation(s)
- Natasha Nagpal
- Oxford Brookes University, School of Psychology, Social Work and Public Health, Oxford, UK
| | - Silvana S Bettiol
- School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Amy Isham
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
| | - Ha Hoang
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
| | - Leonard A Crocombe
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
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Baek HJ, Kim EK, Lee SG, Jeong SH, Sakong J, Merchant AT, Im SU, Song KB, Choi YH. Dental amalgam exposure can elevate urinary mercury concentrations in children. Int Dent J 2016; 66:136-43. [PMID: 26833490 DOI: 10.1111/idj.12214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVES Owing to its cost-effectiveness and operative convenience, dental amalgam remains in use as a restorative material for tooth caries in children in many countries. The aim of this study was to evaluate the relationship between dental amalgam exposure and urinary mercury (U-Hg) concentrations in children. METHODS In this longitudinal study, 463, 367 and 348 children, 8-11 years of age, were evaluated at baseline, and at the first and second follow-up visits, respectively. The interval between each survey was 6 months. For the oral examination and urine sample, the amalgam-filled tooth surface (TS), and U-Hg and creatinine concentrations of participants were determined, and the cumulative amalgam-filled TS and cumulative creatinine-adjusted U-Hg were calculated. To assess potential covariates, socio-demographic factors, oral health behaviour and dietary factors were surveyed by questionnaire. Data were analysed by the t-test, correlation analysis and mixed-model analysis. The statistical analyses were performed using SPSS 18.0. RESULTS Children with more than one amalgam-filled TS exhibited significantly higher creatinine-adjusted U-Hg concentrations than those without, in all three survey periods (P < 0.001). The results for the current and cumulative amalgam-filled TS significantly correlated with those for the current and cumulative creatinine-adjusted U-Hg concentration, respectively, in all surveys (P < 0.001). In the repeated-measures mixed model analysis, current and cumulative amalgam-filled TS was significantly related to current and cumulative creatinine-adjusted U-Hg concentration, respectively (P < 0.001). CONCLUSIONS Amalgam-filled TS was significantly correlated with U-Hg concentrations in children. Therefore, dental amalgam exposure can affect the systemic mercury concentration in children.
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Affiliation(s)
- Hye-Jin Baek
- Department of Dental Hygiene, Taegu Science University 47 Yeongsong-ro Buk-gu, Daegu, Korea
| | - Eun-Kyong Kim
- Department of Dental Hygiene, College of Science & Technology, Kyungpook National University, Daegu, Korea
| | - Sang Gyu Lee
- Department of Hospital Management, Graduate School of Public Health, Yonsei University, Seodaemun-gu, Seoul, Korea
| | - Seong-Hwa Jeong
- Faculty of Health Science, Daegu Haany University 1 Haanydae-ro, Gyeongsan-si, Gyeongsangbuk-do, Korea
| | - Jun Sakong
- Department of Preventive Medicine and Public Health College of Medicine, Yeungnam University 170 Hyunchung-ro, Nam-gu, Daegu, Korea
| | - Anwar T Merchant
- Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Sang-Uk Im
- Department of Preventive Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea
| | - Keun-Bae Song
- Department of Preventive Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea
| | - Youn-Hee Choi
- Department of Preventive Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea
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Golding J, Steer CD, Gregory S, Lowery T, Hibbeln JR, Taylor CM. Dental associations with blood mercury in pregnant women. Community Dent Oral Epidemiol 2015; 44:216-22. [PMID: 26688340 PMCID: PMC4840325 DOI: 10.1111/cdoe.12208] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 11/16/2015] [Indexed: 12/01/2022]
Abstract
Objectives There is curiosity concerning the source of mercury that is absorbed into the mother's blood and which may affect the developing fetus. This study therefore sets out to determine the extent to which dental amalgam (DA) may contribute to total blood mercury (TBHg) levels of pregnant women in the UK. Methods Whole blood samples and information on diet and socio‐demographic factors were collected from pregnant women (n = 4484) enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). The whole blood samples were assayed for total mercury levels using inductively coupled plasma dynamic reaction cell mass spectrometry (ICP‐DRC‐MS), and the women were retrospectively asked about features of their dental care during the pregnancy. Linear regression was used to estimate the relative contributions of DA to TBHg levels (log‐transformed) based on R2 values, compared to the results from dietary and socio‐demographic variables. Results The contribution to the variance of the mothers' TBHg levels by dental variables was 6.47%, a figure comparable to the 8.75% shown for seafood consumption in this population. Dietary and dental variables explained 20.16% of the variance, with socio‐demographic variables contributing only a further 3.40%. The number of amalgams in the mouth at the start of pregnancy accounted for most of the variance in dental variables. Conclusions Dental amalgam contributes a comparable amount of variance in TBHg to seafood consumption in this population. However, because the measures of DA exposure were imprecise, these findings are likely to be an underestimate. There is no evidence to date in the literature that fetal exposures to mercury from maternal DAs have adverse effects on the developing child, but long‐term studies are warranted.
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Affiliation(s)
- Jean Golding
- Centre for Child and Adolescent Health, School of Social & Community Medicine, University of Bristol, Bristol, UK
| | - Colin D Steer
- Centre for Child and Adolescent Health, School of Social & Community Medicine, University of Bristol, Bristol, UK
| | - Steven Gregory
- Centre for Child and Adolescent Health, School of Social & Community Medicine, University of Bristol, Bristol, UK
| | - Tony Lowery
- National Seafood Inspection Laboratory, National Marine Fisheries Service, National Oceanic & Atmospheric Administration, Pascagoula, MS, USA
| | - Joseph R Hibbeln
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Caroline M Taylor
- Centre for Child and Adolescent Health, School of Social & Community Medicine, University of Bristol, Bristol, UK
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Al-Saleh I, Abduljabbar M, Al-Rouqi R, Eltabache C, Al-Rajudi T, Elkhatib R, Nester M. The extent of mercury (Hg) exposure among Saudi mothers and their respective infants. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:678. [PMID: 26450688 DOI: 10.1007/s10661-015-4858-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 09/09/2015] [Indexed: 06/05/2023]
Abstract
A total of 1016 healthy Saudi mothers and their respective infants (aged 3-12 months) were recruited from 57 Primary Health Care Centers (PHCCs) in Riyadh, Saudi Arabia, to evaluate the extent of mercury (Hg) exposure and predict its sources in the healthy Saudi population. Total Hg levels were measured in maternal urine, breast milk, blood, and hair and in the infants' urine and hair. Only 1.9% of the mothers had urinary Hg (UHg)>10 μg/l, the limit for asymptomatic adults recommended by the World Health Organization, but the median (0.99 μg/l) was higher than in other countries. Also, 49.3% of the mothers had UHg>1 μg/l, the German reference value for adults. Median infant UHg was 0.729 μg/l, and 77 and 93 % of the infants had levels higher than 0.4 and 0.1 μg/l, the reference values of the Centers for Disease Control and Prevention and for Germany, respectively. The median Hg level in breast milk was 0.884 μg/l. Even though 43.2% of the milk samples were above the background level for Hg in human milk (1 μg/l), our results were lower than those reported from other countries. Median maternal total Hg in blood was 0.637 μg/l, and only 0.4 and 6.9% of samples were higher than the Hg reference levels of 5.8 μg/l of the Environmental Protection Agency (EPA) and of 2 μg/l for Germany, respectively. Total Hg levels in hair (HHg) varied widely among mothers and infants, but only 3.9% of the mothers and 2.8% of the infants had HHg>1 μg/g (the EPA reference level). Median HHg values were 0.117 μg/g dry weight in mothers and 0.1 μg/g dry weight in infants; both were lower than in other countries. The Hg levels in mothers and their respective infants were relatively low, but our results were consistent with other studies indicating that dental amalgam fillings and fish consumption were the main predictors of maternal Hg exposure. Among the several biomarkers of Hg exposure, Hg levels in maternal hair and urine were the strongest predictors of infant exposure. The lack of an association between Hg in breast milk and Hg in infant urine and hair suggested that the infants were exposed to Hg predominately during pregnancy rather than during breastfeeding. We expect that our data can serve as a baseline for further biomonitoring and follow-up studies, particularly of the long-term impact of Hg on childhood neurodevelopment.
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Affiliation(s)
- Iman Al-Saleh
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia.
| | - Mai Abduljabbar
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
| | - Reem Al-Rouqi
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
| | - Chafica Eltabache
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
| | - Tahreer Al-Rajudi
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
| | - Rola Elkhatib
- Environmental Health Section, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
| | - Michael Nester
- Department of Neurosciences, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia
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19
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Anglen J, Gruninger SE, Chou HN, Weuve J, Turyk ME, Freels S, Stayner LT. Occupational mercury exposure in association with prevalence of multiple sclerosis and tremor among US dentists. J Am Dent Assoc 2015; 146:659-668.e1. [DOI: 10.1016/j.adaj.2015.05.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/12/2015] [Accepted: 05/17/2015] [Indexed: 10/23/2022]
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20
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Haleem NYA, El-Aasar HM, Zaki SM, Sabry SM, El-Zainy AW. Concomitant protective and therapeutic role of verapamil in chronic mercury induced nephrotoxicity in the adult rat: histological, morphometric and ultrastructural study. Arch Med Sci 2015; 11:199-209. [PMID: 25861308 PMCID: PMC4379360 DOI: 10.5114/aoms.2013.37342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Revised: 07/16/2012] [Accepted: 11/09/2012] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Mercury intoxication is a widespread problem as mercury is used in the manufacture of thermometers, batteries and electrical switches. It forms one of the most diffusible environmental pollutants. Mercury has a nephrotoxic effect which could occur at low exposure levels. Verapamil could help in the treatment of mercuric toxicity. The aim of the study was to examine the protective and therapeutic effect of concomitant verapamil on chronic mercuric chloride nephrotoxicity. This was done through histological, morphometric and transmission electron microscopic studies. MATERIAL AND METHODS Sixty adult male albino rats were used. The rats were divided into a control group and 4 experimental groups: group I (HgCl2), group II (concomitant HgCl2 and verapamil), group III (HgCl2 withdrawal) and group IV (HgCl2 withdrawal then verapamil treatment). RESULTS Chronic administration of HgCl2 resulted in cortical nephrotoxic effects in the form of glomerular sclerosis, acute tubular necrosis and interstitial inflammatory cellular infiltration which eventually ended in interstitial fibrosis. Concomitant use of verapamil with HgCl2 improved the previous pathological changes partially. The findings in group III were less severe compared to group IV. The persistence of the pathological findings in these groups reflects the irreversible nephrotoxic changes caused by chronic HgCl2 exposure. CONCLUSIONS We concluded that the concomitant administration of verapamil has a much better effect in minimizing the nephrotoxic effect caused by chronic HgCl2 than its therapeutic administration. So, we recommended the prophylactic use of verapamil in suspected cases of chronic mercuric chloride nephrotoxicity to preserve renal function.
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Nielsen SJ, Aoki Y, Kit BK, Ogden CL. More than half of US youth consume seafood and most have blood mercury concentrations below the EPA reference level, 2009-2012. J Nutr 2015; 145:322-7. [PMID: 25644354 PMCID: PMC7289318 DOI: 10.3945/jn.114.203786] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Consuming seafood has health benefits, but seafood can also contain methylmercury, a neurotoxicant. Exposure to methylmercury affects children at different stages of brain development, including during adolescence. OBJECTIVE The objective was to examine seafood consumption and blood mercury concentrations in US youth. METHODS In the 2009-2012 NHANES, a cross-sectional nationally representative sample of the US population, seafood consumption in the past 30 d and blood mercury concentrations on the day of examination were collected from 5656 youth aged 1-19 y. Log-linear regression was used to examine the association between frequency of specific seafood consumption and blood mercury concentration, adjusting for race/Hispanic origin, sex, and age. RESULTS In 2009-2012, 62.4% ± 1.4% (percent ± SE) of youth consumed any seafood in the preceding month; 38.4% ± 1.4% and 48.5% ± 1.5% reported consuming shellfish and fish, respectively. In 2009-2012, the geometric mean blood mercury concentration was 0.50 ± 0.02 μg/L among seafood consumers and 0.27 ± 0.01 μg/L among those who did not consume seafood. Less than 0.5% of youth had blood mercury concentrations ≥5.8 μg/L. In adjusted log-linear regression analysis, no significant associations were observed between frequency of breaded fish or catfish consumption and blood mercury concentrations, but frequency of consuming certain seafood types had significant positive association with blood mercury concentrations: high-mercury fish (swordfish and shark) [exponentiated β coefficient (expβ): 2.40; 95% CI: 1.23, 4.68]; salmon (expβ: 1.41; 95% CI: 1.26, 1.55); tuna (expβ: 1.38; 95% CI: 1.29, 1.45); crabs (expβ: 1.35; 95% CI: 1.17, 1.55); shrimp (expβ: 1.12; 95% CI: 1.05, 1.20), and all other seafood (expβ: 1.23; 95% CI: 1.17, 1.32). Age-stratified log-linear regression analyses produced similar results. CONCLUSION Few US youth have blood mercury concentrations ≥5.8 μg/L, although more than half of US youth consumed seafood in the past month.
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Affiliation(s)
- Samara Joy Nielsen
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, MD; and
| | - Yutaka Aoki
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, MD; and
| | - Brian K Kit
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, MD; and US Public Health Service, Rockville, MD
| | - Cynthia L Ogden
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, MD; and
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Motts JA, Shirley DL, Silbergeld EK, Nyland JF. Novel biomarkers of mercury-induced autoimmune dysfunction: a cross-sectional study in Amazonian Brazil. ENVIRONMENTAL RESEARCH 2014; 132:12-8. [PMID: 24742722 PMCID: PMC4060520 DOI: 10.1016/j.envres.2014.03.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 01/30/2014] [Accepted: 03/18/2014] [Indexed: 05/23/2023]
Abstract
Mercury is a ubiquitous environmental contaminant, causing both neurotoxicity and immunotoxicity. Given its ability to amalgamate gold, mercury is frequently used in small-scale artisanal gold mining. We have previously reported that elevated serum titers of antinuclear autoantibodies (ANA) are associated with mercury exposures of miners in gold mining. The goal of this project was to identify novel serum biomarkers of mercury-induced immunotoxicity and autoimmune dysregulation. We conducted an analysis of serum samples from a cross-sectional epidemiological study on miners working in Amazonian Brazil. In proteomic screening analyses, samples were stratified based on mercury concentrations and ANA titer and a subset of serum samples (N=12) were profiled using Immune Response Biomarker Profiling ProtoArray protein microarray for elevated autoantibodies. Of the up-regulated autoantibodies in the mercury-exposed cohort, potential target autoantibodies were selected based on relevance to pro-inflammatory and macrophage activation pathways. ELISAs were developed to test the entire sample cohort (N=371) for serum titers to the highest of these autoantibodies (anti-glutathione S-transferase alpha, GSTA1) identified in the high mercury/high ANA group. We found positive associations between elevated mercury exposure and up-regulated serum titers of 3760 autoantibodies as identified by ProtoArray. Autoantibodies identified as potential novel biomarkers of mercury-induced immunotoxicity include antibodies to the following proteins: GSTA1, tumor necrosis factor ligand superfamily member 13, linker for activation of T cells, signal peptide peptidase like 2B, stimulated by retinoic acid 13, and interferon induced transmembrane protein. ELISA analyses confirmed that mercury-exposed gold miners had significantly higher serum titers of anti-GSTA1 autoantibody [unadjusted odds ratio=89.6; 95% confidence interval: 27.2, 294.6] compared to emerald miners (referent population). Mercury exposure was associated with increased titers of several autoantibodies in serum including anti-GSTA1. These proteins play a wide variety of roles, including as antioxidants, in the regulation of pro- and anti-inflammatory cytokines, as well as danger and oxidative stress signaling. Dysregulation of these proteins and pathways is believed to play a role in autoimmune diseases such as rheumatoid arthritis, Sjögren׳s syndrome, and multiple sclerosis. Taken together, these results suggest that mercury exposure can induce complex autoimmune dysfunction and the immunotoxic effects of this dysfunction may be measured by serum titers to autoantibodies such as anti-GSTA1.
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Affiliation(s)
- Jonathan A Motts
- Department of Biology, University of South Carolina, Columbia, SC 29209, USA
| | - Devon L Shirley
- Department of Pathology, Microbiology & Immunology, University of South Carolina, School of Medicine, Columbia, SC, USA
| | - Ellen K Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jennifer F Nyland
- Department of Pathology, Microbiology & Immunology, University of South Carolina, School of Medicine, Columbia, SC, USA.
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Sheehan MC, Burke TA, Navas-Acien A, Breysse PN, McGready J, Fox MA. Global methylmercury exposure from seafood consumption and risk of developmental neurotoxicity: a systematic review. Bull World Health Organ 2014; 92:254-269F. [PMID: 24700993 PMCID: PMC3967569 DOI: 10.2471/blt.12.116152] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 10/15/2013] [Accepted: 11/12/2013] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To examine biomarkers of methylmercury (MeHg) intake in women and infants from seafood-consuming populations globally and characterize the comparative risk of fetal developmental neurotoxicity. METHODS A search was conducted of the published literature reporting total mercury (Hg) in hair and blood in women and infants. These biomarkers are validated proxy measures of MeHg, a neurotoxin found primarily in seafood. Average and high-end biomarkers were extracted, stratified by seafood consumption context, and pooled by category. Medians for average and high-end pooled distributions were compared with the reference level established by a joint expert committee of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO). FINDINGS Selection criteria were met by 164 studies of women and infants from 43 countries. Pooled average biomarkers suggest an intake of MeHg several times over the FAO/WHO reference in fish-consuming riparians living near small-scale gold mining and well over the reference in consumers of marine mammals in Arctic regions. In coastal regions of south-eastern Asia, the western Pacific and the Mediterranean, average biomarkers approach the reference. Although the two former groups have a higher risk of neurotoxicity than the latter, coastal regions are home to the largest number at risk. High-end biomarkers across all categories indicate MeHg intake is in excess of the reference value. CONCLUSION There is a need for policies to reduce Hg exposure among women and infants and for surveillance in high-risk populations, the majority of which live in low-and middle-income countries.
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Affiliation(s)
- Mary C Sheehan
- Risk Sciences and Public Policy Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, United States of America (USA)
| | - Thomas A Burke
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Ana Navas-Acien
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Patrick N Breysse
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - John McGready
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Mary A Fox
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
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Blood mercury concentrations in pregnant and nonpregnant women in the United States: National Health and Nutrition Examination Survey 1999-2006. Am J Obstet Gynecol 2014; 210:357.e1-357.e9. [PMID: 24189168 DOI: 10.1016/j.ajog.2013.10.884] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 09/20/2013] [Accepted: 10/30/2013] [Indexed: 11/21/2022]
Abstract
BACKGROUND Prenatal exposure to methylmercury is associated with adverse neurologic development in children. We examined total blood mercury concentrations and predictors of higher blood mercury concentrations in pregnant and nonpregnant women. METHODS We analyzed data from 1183 pregnant and 5587 nonpregnant women aged 16-49 years from the 1999-2006 National Health and Nutrition Examination Survey (NHANES). We estimated geometric mean blood mercury concentrations and characteristics associated with higher mercury concentrations (≥3.5 μg/L) in crude and adjusted linear and logistic regression models. RESULTS After adjusting for age and race/ethnicity, geometric mean blood mercury concentrations were clinically similar but significantly lower for pregnant (0.81 μg/L; 95% confidence interval [CI], 0.71-0.91) and nonpregnant women of childbearing age (0.93 μg/L; 95% CI, 0.87-0.99); 94% of pregnant and 89% of nonpregnant women had blood mercury concentrations below 3.5 μg/L. The most significant predictor of higher blood mercury concentrations for both pregnant and nonpregnant women was any seafood consumption vs no consumption in the last 30 days (odds ratio, 18.7; 95% CI, 4.9-71.1; odds ratio, 15.5; 95% CI, 7.5-32.1, respectively). Other characteristics associated with ≥3.5 μg/L blood mercury concentrations were older age (≥35 years), higher education (greater than high school), and higher family income to poverty ratio (3.501+) for both pregnant and nonpregnant women. CONCLUSION Pregnancy status was not strongly associated with blood mercury concentrations in women of childbearing age and blood mercury concentrations above the 3.5 μg/L cut were uncommon.
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Nicolae A, Ames H, Quiñonez C. Dental amalgam and urinary mercury concentrations: a descriptive study. BMC Oral Health 2013; 13:44. [PMID: 24015978 PMCID: PMC3847647 DOI: 10.1186/1472-6831-13-44] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 08/29/2013] [Indexed: 11/16/2022] Open
Abstract
Background Dental amalgam is a source of elemental and inorganic mercury. The safety of dental amalgam in individuals remains a controversial issue. Urinary mercury concentrations are used to assess chronic exposure to elemental mercury. At present, there are no indications of mercury-associated adverse effects at levels below 5 μg Hg/g creatinine (Cr) or 7 μg Hg/L (urine). The purpose of the present study is to determine the overall urinary mercury level in the Canadian general population in relation to the number of dental amalgam surfaces. Methods Data come from the 2007/09 Canadian Health Measures Survey, which measured urinary mercury concentrations in a nationally representative sample of 5,418 Canadians aged 6–79 years. Urinary mercury concentrations were stratified by sex, age, and number of dental amalgam surfaces. Results The overall mean urinary mercury concentration varied between 0.12 μg Hg/L and 0.31 μg Hg/L or 0.13 μg Hg/g Cr and 0.40 μg Hg/g Cr. In general, females showed slightly higher mean urinary mercury levels than men. The overall 95th percentile was 2.95 μg Hg/L, the 99th percentile was 7.34E μg Hg/L, and the 99.9th percentile was 17.45 μg Hg/L. Expressed as μg Hg/g Cr, the overall 95th percentile was 2.57 μg Hg/g Cr, the 99th percentile was 5.65 μg Hg/g Cr, and the 99.9th percentiles was 12.14 μg Hg/g Cr. Overall, 98.2% of participants had urinary mercury levels below 7 μg Hg/L and 97.7% had urinary mercury levels below 5 μg Hg/g Cr. All data are estimates for the Canadian population. The estimates followed by the letter “E” should be interpreted with caution due to high sampling variability (coefficient of variation 16.6%-33.3%). Conclusions The mean urinary mercury concentrations in the general Canadian population are significantly lower than the values considered to pose any risks for health.
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Affiliation(s)
- Alexandra Nicolae
- Community Dental Health Services Research Unit, University of Toronto, 124 Edward Street, M5G 1G6, Toronto, ON, Canada.
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Syversen T, Kaur P. The toxicology of mercury and its compounds. J Trace Elem Med Biol 2012; 26:215-26. [PMID: 22658719 DOI: 10.1016/j.jtemb.2012.02.004] [Citation(s) in RCA: 231] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 02/07/2012] [Indexed: 12/27/2022]
Abstract
A concentrated review on the toxicology of inorganic mercury together with an extensive review on the neurotoxicology of methylmercury is presented. The challenges of using inorganic mercury in dental amalgam are reviewed both regarding the occupational exposure and the possible health problems for the dental patients. The two remaining "mysteries" of methylmercury neurotoxicology are also being reviewed; the cellular selectivity and the delayed onset of symptoms. The relevant literature on these aspects has been discussed and some suggestions towards explaining these observations have been presented.
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Affiliation(s)
- Tore Syversen
- Norwegian University of Science and Technology, Department of Neuroscience, Trondheim, Norway.
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Richardson GM, Wilson R, Allard D, Purtill C, Douma S, Gravière J. Mercury exposure and risks from dental amalgam in the US population, post-2000. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:4257-68. [PMID: 21782213 DOI: 10.1016/j.scitotenv.2011.06.035] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 06/08/2011] [Accepted: 06/15/2011] [Indexed: 05/24/2023]
Abstract
Dental amalgam is 50% metallic mercury (Hg) by weight and Hg vapour continuously evolves from in-place dental amalgam, causing increased Hg content with increasing amalgam load in urine, faeces, exhaled breath, saliva, blood, and various organs and tissues including the kidney, pituitary gland, liver, and brain. The Hg content also increases with maternal amalgam load in amniotic fluid, placenta, cord blood, meconium, various foetal tissues including liver, kidney and brain, in colostrum and breast milk. Based on 2001 to 2004 population statistics, 181.1 million Americans carry a grand total of 1.46 billion restored teeth. Children as young as 26 months were recorded as having restored teeth. Past dental practice and recently available data indicate that the majority of these restorations are composed of dental amalgam. Employing recent US population-based statistics on body weight and the frequency of dentally restored tooth surfaces, and recent research on the incremental increase in urinary Hg concentration per amalgam-filled tooth surface, estimates of Hg exposure from amalgam fillings were determined for 5 age groups of the US population. Three specific exposure scenarios were considered, each scenario incrementally reducing the number of tooth surfaces assumed to be restored with amalgam. Based on the least conservative of the scenarios evaluated, it was estimated that some 67.2 million Americans would exceed the Hg dose associated with the reference exposure level (REL) of 0.3 μg/m(3) established by the US Environmental Protection Agency; and 122.3 million Americans would exceed the dose associated with the REL of 0.03 μg/m(3) established by the California Environmental Protection Agency. Exposure estimates are consistent with previous estimates presented by Health Canada in 1995, and amount to 0.2 to 0.4 μg/day per amalgam-filled tooth surface, or 0.5 to 1 μg/day/amalgam-filled tooth, depending on age and other factors.
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Affiliation(s)
- G M Richardson
- SNC-Lavalin Environment, Suite 110, 20 Colonnade Road, Ottawa, ON Canada.
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Geier DA, Carmody T, Kern JK, King PG, Geier MR. A dose-dependent relationship between mercury exposure from dental amalgams and urinary mercury levels: a further assessment of the Casa Pia Children's Dental Amalgam Trial. Hum Exp Toxicol 2011; 31:11-7. [PMID: 21803780 DOI: 10.1177/0960327111417264] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dental amalgams are a commonly used dental restorative material, and amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8-18 years, with and without dental amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposure to amalgams, in comparison to study subjects with no exposure to amalgams. The results of our study suggest that dental amalgams contribute to ongoing Hg exposure in a dose-dependent fashion.
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Affiliation(s)
- D A Geier
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA
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Trachtenberg F, Barregard L, Maserejian N, McKinlay S. Methodological considerations with the use of urine samples for assessment of mercury excretion and markers of renal damage. Biomarkers 2010; 15:639-45. [PMID: 20863154 DOI: 10.3109/1354750x.2010.510581] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To provide recommendations for design and analysis of studies using urine specimens to evaluate renal function or mercury excretion in children. METHODS An analysis of mercury, albumin, γ-glutamyl transpeptidase (γ-GT) and N-acetyl-β-D-glucosaminidase (NAG) concentrations was carried out. RESULTS Mercury concentration and creatinine-corrected renal markers were higher in daytime compared with overnight samples. Excretion rates increased with urinary flow rate. γ-GT and NAG concentrations decreased with storage time at -20°C. Differences by age, sex and race were noted. CONCLUSIONS We recommend use of these creatinine-corrected markers and collection of timed overnight urine samples, stored at -70°C, with control for urinary flow rate, age, sex and race in statistical models.
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Bose-O'Reilly S, McCarty KM, Steckling N, Lettmeier B. Mercury exposure and children's health. Curr Probl Pediatr Adolesc Health Care 2010; 40:186-215. [PMID: 20816346 DOI: 10.1016/j.cppeds.2010.07.002.mercury] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Acute or chronic mercury exposure can cause adverse effects during any period of development. Mercury is a highly toxic element; there is no known safe level of exposure. Ideally, neither children nor adults should have any mercury in their bodies because it provides no physiological benefit. Prenatal and postnatal mercury exposures occur frequently in many different ways. Pediatricians, nurses, and other health care providers should understand the scope of mercury exposures and health problems among children and be prepared to handle mercury exposures in medical practice. Prevention is the key to reducing mercury poisoning. Mercury exists in different chemical forms: elemental (or metallic), inorganic, and organic (methylmercury and ethyl mercury). Mercury exposure can cause acute and chronic intoxication at low levels of exposure. Mercury is neuro-, nephro-, and immunotoxic. The development of the child in utero and early in life is at particular risk. Mercury is ubiquitous and persistent. Mercury is a global pollutant, bio-accumulating, mainly through the aquatic food chain, resulting in a serious health hazard for children. This article provides an extensive review of mercury exposure and children's health.
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Affiliation(s)
- Stephan Bose-O'Reilly
- Institute of Public Health, Medical Decision Making and Health Technology Assessment, Department of Public Health, Information Systems and Health Technology Assessment, UMIT-University for Health Sciences, Medical Informatics and Technology, Hall i.T, Austria
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Abstract
Acute or chronic mercury exposure can cause adverse effects during any period of development. Mercury is a highly toxic element; there is no known safe level of exposure. Ideally, neither children nor adults should have any mercury in their bodies because it provides no physiological benefit. Prenatal and postnatal mercury exposures occur frequently in many different ways. Pediatricians, nurses, and other health care providers should understand the scope of mercury exposures and health problems among children and be prepared to handle mercury exposures in medical practice. Prevention is the key to reducing mercury poisoning. Mercury exists in different chemical forms: elemental (or metallic), inorganic, and organic (methylmercury and ethyl mercury). Mercury exposure can cause acute and chronic intoxication at low levels of exposure. Mercury is neuro-, nephro-, and immunotoxic. The development of the child in utero and early in life is at particular risk. Mercury is ubiquitous and persistent. Mercury is a global pollutant, bio-accumulating, mainly through the aquatic food chain, resulting in a serious health hazard for children. This article provides an extensive review of mercury exposure and children's health.
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Affiliation(s)
- Stephan Bose-O'Reilly
- Institute of Public Health, Medical Decision Making and Health Technology Assessment, Department of Public Health, Information Systems and Health Technology Assessment, UMIT-University for Health Sciences, Medical Informatics and Technology, Hall i.T, Austria
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Gardner RM, Nyland JF, Silva IA, Ventura AM, Souza JMD, Silbergeld EK. Mercury exposure, serum antinuclear/antinucleolar antibodies, and serum cytokine levels in mining populations in Amazonian Brazil: a cross-sectional study. ENVIRONMENTAL RESEARCH 2010; 110:345-54. [PMID: 20176347 PMCID: PMC2873228 DOI: 10.1016/j.envres.2010.02.001] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 01/29/2010] [Accepted: 02/02/2010] [Indexed: 05/19/2023]
Abstract
Mercury is an immunotoxic substance that has been shown to induce autoimmune disease in rodent models, characterized by lymphoproliferation, overproduction of immunoglobulin (IgG and IgE), and high circulating levels of auto-antibodies directed at antigens located in the nucleus (antinuclear auto-antibodies, or ANA) or the nucleolus (antinucleolar auto-antibodies, or ANoA). We have reported elevated levels of ANA and ANoA in human populations exposed to mercury in artisanal gold mining, though other confounding variables that may also modulate ANA/ANoA levels were not well controlled. The goal of this study is to specifically test whether occupational and environmental conditions (other than mercury exposure) that are associated with artisanal gold mining affect the prevalence of markers of autoimmune dysfunction. We measured ANA, ANoA, and cytokine concentrations in serum and compared results from mercury-exposed artisanal gold miners to those from diamond and emerald miners working under similar conditions and with similar socio-economic status and risks of infectious disease. Mercury-exposed gold miners had higher prevalence of detectable ANA and ANoA and higher titers of ANA and ANoA as compared to diamond and emerald miners with no occupational mercury exposure. Also, mercury-exposed gold miners with detectable ANA or ANoA in serum had significantly higher concentrations of pro-inflammatory cytokines IL-1beta, TNF-alpha, and IFN-gamma in serum as compared to the diamond and emerald miners. This study provides further evidence that mercury exposure may lead to autoimmune dysfunction and systemic inflammation in affected populations.
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Affiliation(s)
- Renee M. Gardner
- Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, MD 21205
| | - Jennifer F. Nyland
- Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, MD 21205
- University of South Carolina School of Medicine, Department of Pathology, Microbiology & Immunology, Columbia, SC 29209
| | - Ines A. Silva
- Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, MD 21205
| | - Ana Maria Ventura
- Institute Evandro Chagas (IEC), Fundaçao Nacional da Saúde, Belem do Pará-66090, Brazil
| | - Jose Maria de Souza
- Institute Evandro Chagas (IEC), Fundaçao Nacional da Saúde, Belem do Pará-66090, Brazil
| | - Ellen K. Silbergeld
- Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, MD 21205
- Corresponding Author: Ellen K. Silbergeld, Johns Hopkins Bloomberg School of Public Health, Environmental Health Sciences, 615 N. Wolfe St., Room E6644, Baltimore, MD, 21205, Phone: (410) 955-8678, Fax: (443) 287-6414,
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Abstract
OBJECTIVE To know the variability of the creatinine-adjusted inorganic mercury (HgUCr) levels in women aged >or=12 years to evaluate the impact of residing at a site contaminated by mercury in soil. METHODS A cross-sectional epidemiologic study was conducted, in which 122 women participated, in whom, HgUCr was determined. Simultaneously, a questionnaire was applied for evaluate the different factors of mercury exposure, sociodemographic characteristics, and dietary hygiene measures. The environmental exposures were evaluated by measure Hg in soil and mining dumps. RESULTS Women aged >30 years residing in areas contaminated by Hg in soil (>625 ppb) had 212% more HgUCr than the women who living in areas least contaminated, while women with amalgam dental fillings had 120% more HgUCr than women without these. CONCLUSION In conclusion, exposure to different physicochemical forms of Hg by environmental mechanisms and factors intrinsic to the women are probably responsible for HgUCr-level variability in the women.
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L’imprégnation mercurielle des dentistes et de leurs assistants dans la ville de Monastir, Tunisie. ACTA ACUST UNITED AC 2009; 110:139-44. [DOI: 10.1016/j.stomax.2009.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Revised: 01/15/2009] [Accepted: 01/22/2009] [Indexed: 11/20/2022]
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Response to Mutter et al. From Laszlo Magos and Tom Clarkson. Crit Rev Toxicol 2008. [DOI: 10.1080/10408440701385796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Affiliation(s)
- Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge Massachusetts 02139, USA
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Roberts M, Leroux B, Sampson J, Luis H, Bernardo M, Leitão J. Dental Amalgam and Antibiotic- and/or Mercury-resistant Bacteria. J Dent Res 2008; 87:475-9. [DOI: 10.1177/154405910808700502] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mercury emitted from dental amalgam may select for increased numbers of antibiotic- or mercury-resistant commensal bacteria in patients and increase their risk for bacterial diseases that are resistant to common therapies. We hypothesized that the presence of dental amalgams would increase the level of mercury-, tetracycline-, ampicillin-, erythromycin-, or chloramphenicol-resistant oral and urinary bacteria as compared with levels in children receiving composite fillings. Samples were collected at baseline, 3–6 months after the initial dental treatment, and annually for 7 years of follow-up. There were no statistically significant differences between treatment groups in the numbers of bacteria growing on antibiotic- or mercury-supplemented plates. This study provided no evidence that amalgam fillings on posterior teeth influenced the level of antibiotic- or mercury-resistant oral or urinary bacteria as detected by culture.
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Affiliation(s)
- M.C. Roberts
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
| | - B.G. Leroux
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
| | - J. Sampson
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
| | - H.S. Luis
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
| | - M. Bernardo
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
| | - J. Leitão
- Box 357234, Departments of, Environmental and Occupational Health Sciences, and
- Dental Public Health Sciences, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98195, USA; and
- Faculty of Dental Medicine, Universidade de Lisboa, Lisbon, Portugal
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Barregard L, Trachtenberg F, McKinlay S. Renal effects of dental amalgam in children: the New England children's amalgam trial. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:394-9. [PMID: 18335109 PMCID: PMC2265055 DOI: 10.1289/ehp.10504] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Accepted: 11/23/2007] [Indexed: 05/24/2023]
Abstract
BACKGROUND Mercury is nephrotoxic and dental amalgam is a source of mercury exposure. METHODS Children 6-10 years of age (n = 534) with two or more posterior teeth with caries but no prior amalgam restorations, were randomized to one of two treatments--amalgam or resin composite (white fillings)--used for caries treatment during 5 years of follow-up. The primary outcome was change in IQ, but important secondary outcomes were effects on markers of glomerular and tubular kidney function: urinary excretion of albumin, alpha-1-microglobulin (A1M), gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-beta-d-glucosaminidase (NAG). These markers were measured on several occasions during the trial, together with urinary mercury and covariates. We evaluated the results using repeated-measures analyses. RESULTS There were no significant differences between treatment groups in average levels of renal biomarkers, nor significant effects of number of dental amalgams on these markers. There was, however, a significantly increased prevalence of microalbuminuria (MA) among children in the amalgam group in years 3-5 (adjusted odds ratio 1.8; 95% confidence interval, 1.1-2.9). Most of these cases are likely to be temporary MA, but 10 children in the amalgam group had MA in both years 3 and 5, versus 2 children in the composite group (p = 0.04). There were no differences in the occurrence of high levels of renal tubular markers (A1M, gamma-GT, or NAG). CONCLUSIONS The increase in MA may be a random finding, but should be tested further. The results did not support recent findings in an observational study of an effect of low-level mercury on tubular biomarkers in children.
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Affiliation(s)
- Lars Barregard
- Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and Academy, Gothenburg, Sweden
| | | | - Sonja McKinlay
- New England Research Institutes, Watertown, Massachusetts, USA
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Maserejian NN, Trachtenberg FL, Assmann SF, Barregard L. Dental amalgam exposure and urinary mercury levels in children: the New England Children's Amalgam Trial. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:256-62. [PMID: 18288327 PMCID: PMC2235235 DOI: 10.1289/ehp.10440] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Accepted: 11/11/2007] [Indexed: 05/03/2023]
Abstract
BACKGROUND Urinary mercury (U-Hg) excretion is a commonly used biomarker for mercury exposure from dental amalgam restorations. OBJECTIVES Our goal was to determine the most efficient measure of dental amalgam exposure for use in analyses concerning U-Hg in children. METHODS We analyzed time-sensitive longitudinal amalgam exposure data in children randomized to amalgam restorations (n = 267) during the 5-year New England Children's Amalgam Trial. We calculated 8 measures of amalgam, evaluating current versus cumulative exposure, teeth versus surfaces, and total versus posterior occlusal amalgams. Urine samples collected during follow-up years 3-5 were analyzed for mercury excretion. Multivariate models for current and cumulative U-Hg excretion estimated associations between exposures and U-Hg. RESULTS At the end of follow-up, the average (+/- SD) cumulative exposure was 10.3 +/- 6.1 surfaces and 5.7 +/- 2.9 teeth ever filled with amalgam, corresponding to 30 +/- 21 surface-years. Amalgam measures and U-Hg were moderately correlated. Of amalgam exposure measures, the current total of amalgam surfaces was the most robust predictor of current U-Hg, whereas posterior occlusal surface-years was best for cumulative U-Hg. In multivariate models, each additional amalgam surface present was associated with a 9% increase in current U-Hg, and each additional posterior occlusal surface-year was associated with a 3% increase in cumulative U-Hg excretion (p < 0.001). CONCLUSIONS One single measure of amalgam exposure is insufficient. Studies of cumulative effects of mercury from amalgam exposure in children are likely to have improved validity and precision if time-sensitive amalgam exposure measures are used. In contrast, simple counts of current amalgam fillings are adequate to capture amalgam-related current U-Hg.
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Di Pietro A, Visalli G, La Maestra S, Micale R, Baluce B, Matarese G, Cingano L, Scoglio ME. Biomonitoring of DNA damage in peripheral blood lymphocytes of subjects with dental restorative fillings. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2008; 650:115-22. [DOI: 10.1016/j.mrgentox.2007.10.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2007] [Revised: 09/04/2007] [Accepted: 10/31/2007] [Indexed: 12/19/2022]
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Abstract
Residential exposure to vapor from current or previous cultural use of mercury could harm children living in rental (apartment) homes. That concern prompted the following agencies to conduct a study to assess pediatric mercury exposure in New York City communities by measuring urine mercury levels: New York City Department of Health and Mental Hygiene's (NYCDOHMH) Bureau of Environmental Surveillance and Policy, New York State Department of Health/Center for Environmental Health (NYSDOHCEH), Wadsworth Center's Biomonitoring Program/Trace Elements Laboratory (WC-TEL), and Centers for Disease Control and Prevention (CDC). A previous study indicated that people could obtain mercury for ritualistic use from botanicas located in Brooklyn, Manhattan, and the Bronx. Working closely with local community partners, we concentrated our recruiting efforts through health clinics located in potentially affected neighborhoods. We developed posters to advertise the study, conducted active outreach through local partners, and, as compensation for participation in the study, we offered a food gift certificate redeemable at a local grocer. We collected 460 urine specimens and analyzed them for total mercury. Overall, geometric mean urine total mercury was 0.31 microg mercury/l urine. One sample was 24 microg mercury/l urine, which exceeded the (20 microg mercury/l urine) NYSDOH Heavy Metal Registry reporting threshold for urine mercury exposure. Geometric mean urine mercury levels were uniformly low and did not differ by neighborhood or with any clinical significance by children's ethnicity. Few parents reported the presence of mercury at home, in a charm, or other item (e.g., skin-lightening creams and soaps), and we found no association between these potential sources of exposure and a child's urinary mercury levels. All pediatric mercury levels measured in this study were well below a level considered to be of medical concern. This study found neither self-reported nor measured evidence of significant mercury use or exposure among participating children. Because some participants were aware of the possibility that they could acquire and use mercury for cultural or ritualistic purposes, community education about the health hazards of mercury should continue.
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Beazoglou T, Eklund S, Heffley D, Meiers J, Brown LJ, Bailit H. Economic impact of regulating the use of amalgam restorations. Public Health Rep 2007; 122:657-63. [PMID: 17877313 PMCID: PMC1936958 DOI: 10.1177/003335490712200513] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE This article estimates the financial impact of a ban on amalgam restorations for selected population groups: the entire population, children, and children and women of childbearing age. METHODS Using claim and enrollment data from Delta Dental of Michigan, Ohio, and Indiana and the American Dental Association Survey of Dental Services Rendered, we estimated the per capita use and annual rate of change in amalgam restorations for each age, gender, and socioeconomic subgroup. We used population projections to obtain national estimates of amalgam use, and the dental component of the Consumer Price Index to estimate the annual rate of change in fees. We then calculated the number of dental amalgams affected by the regulation, and the fees for each of the years 2005 to 2020. RESULTS If amalgam restorations are banned for the entire population, the average price of restorations before 2005 and after the ban would increase $52 from $278 to $330, and total expenditures for restorations would increase from $46.2 billion to $49.7 billion. As the price of restorations increases, there would be 15,444,021 fewer restorations inserted per year. The estimated first-year impact of banning dental amalgams in the entire population is an increase in expenditures of $8.2 billion. CONCLUSIONS An amalgam ban would have a substantial short- and long-term impact on increasing expenditures for dental care, decreasing utilization, and increasing untreated disease. Based on the available evidence, we believe that state legislatures should seriously consider these effects when contemplating possible restrictions on the use of amalgam restorations.
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Affiliation(s)
- Tryfon Beazoglou
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, 263 Farmington Ave., Farmington, CT 06030, USA.
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Woods JS, Martin MD, Leroux BG, DeRouen TA, Leitão JG, Bernardo MF, Luis HS, Simmonds PL, Kushleika JV, Huang Y. The contribution of dental amalgam to urinary mercury excretion in children. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115:1527-31. [PMID: 17938746 PMCID: PMC2022658 DOI: 10.1289/ehp.10249] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Accepted: 06/28/2007] [Indexed: 05/06/2023]
Abstract
BACKGROUND Urinary mercury concentrations are widely used as a measure of mercury exposure from dental amalgam fillings. No studies have evaluated the relationship of these measures in a longitudinal context in children. OBJECTIVE We evaluated urinary mercury in children 8-18 years of age in relation to number of amalgam surfaces and time since placement over a 7-year course of amalgam treatment. METHODS Five hundred seven children, 8-10 years of age at baseline, participated in a clinical trial to evaluate the neurobehavioral effects of dental amalgam in children. Subjects were randomized to either dental amalgam or resin composite treatments. Urinary mercury and creatinine concentrations were measured at baseline and annually on all participants. RESULTS Treatment groups were comparable in baseline urinary mercury concentration (approximately 1.5 microg/L). Mean urinary mercury concentrations in the amalgam group increased to a peak of approximately 3.2 microg/L at year 2 and then declined to baseline levels by year 7 of follow-up. There was a strong, positive association between urinary mercury and both number of amalgam surfaces and time since placement. Girls had significantly higher mean urinary mercury concentrations than boys throughout the course of amalgam treatment. There were no differences by race in urinary mercury concentration associated with amalgam exposure. CONCLUSIONS Urinary mercury concentrations are highly correlated with both number of amalgam fillings and time since placement in children. Girls excrete significantly higher concentrations of mercury in the urine than boys with comparable treatment, suggesting possible sex-related differences in mercury handling and susceptibility to mercury toxicity.
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Affiliation(s)
- James S Woods
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington8105, USA.
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Bellinger DC, Daniel D, Trachtenberg F, Tavares M, McKinlay S. Dental amalgam restorations and children's neuropsychological function: the New England Children's Amalgam Trial. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115:440-6. [PMID: 17431496 PMCID: PMC1849920 DOI: 10.1289/ehp.9497] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2006] [Accepted: 10/30/2006] [Indexed: 05/14/2023]
Abstract
BACKGROUND A concern persists that children's exposure to mercury vapor from dental amalgams produces neurotoxicity. OBJECTIVE Our goal was to compare the neuropsychological function of children, without prior exposure to dental amalgam, whose caries were repaired using either dental amalgam or mercury-free composite materials. METHODS We conducted a randomized controlled trial involving 534 6- to 10-year-old urban and rural children who were assessed yearly for 5 years using a battery of tests of intelligence, achievement, language, memory, learning, visual-spatial skills, verbal fluency, fine motor function, problem solving, attention, and executive function. RESULTS Although the mean urinary mercury concentration was greater among children in the amalgam group than the composite group (0.9 vs. 0.6 microg/g creatinine), few significant differences were found between the test scores of children in the two groups. The differences found were inconsistent in direction. Analyses using two cumulative exposure indices--surface years of amalgam and urinary mercury concentration--produced similar results. CONCLUSIONS Exposure to elemental mercury in amalgam at the levels experienced by the children who participated in the trial did not result in significant effects on neuropsychological function within the 5-year follow-up period.
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Affiliation(s)
- David C. Bellinger
- Department of Neurology, Children’s Hospital Boston and Harvard Medical School and
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
| | - David Daniel
- Department of Psychology, University of Maine at Farmington, Farmington, Maine, USA
| | | | - Mary Tavares
- The Forsyth Institute, Boston, Massachusetts, USA
| | - Sonja McKinlay
- New England Research Institutes, Watertown, Massachusetts, USA
- Address correspondence to S. McKinlay, New England Research Institutes, 9 Galen St., Watertown, MA 02472 USA. Telephone: (617) 923-7747. Fax: (617) 926-0144. E-mail:
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Abstract
This review covers the toxicology of mercury and its compounds. Special attention is paid to those forms of mercury of current public health concern. Human exposure to the vapor of metallic mercury dates back to antiquity but continues today in occupational settings and from dental amalgam. Health risks from methylmercury in edible tissues of fish have been the subject of several large epidemiological investigations and continue to be the subject of intense debate. Ethylmercury in the form of a preservative, thimerosal, added to certain vaccines, is the most recent form of mercury that has become a public health concern. The review leads to general discussion of evolutionary aspects of mercury, protective and toxic mechanisms, and ends on a note that mercury is still an "element of mystery."
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Affiliation(s)
- Thomas W Clarkson
- Department of Environmental Medicine, University of Rochester School of Medicine, New York, USA.
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Hightower JM, O'Hare A, Hernandez GT. Blood mercury reporting in NHANES: identifying Asian, Pacific Islander, Native American, and multiracial groups. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:173-5. [PMID: 16451850 PMCID: PMC1367827 DOI: 10.1289/ehp.8464] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2005] [Accepted: 09/21/2005] [Indexed: 05/06/2023]
Abstract
INTRODUCTION Asians, Pacific Islanders, and Native Americans are a potentially high-risk group for dietary exposure to methylmercury through fish consumption. However, blood mercury levels in this group have not been identified in recent reports of the National Health and Nutrition Examination Survey (NHANES) for the years 1999-2002. METHODS We used NHANES data from 1999-2002 to obtain population estimates of blood mercury levels among women of childbearing age classified as belonging to the "other" racial/ethnic group (Asian, Pacific Islander, Native American, and multiracial; n = 140). Blood mercury levels in this group were compared with those among all other women participants, classified as Mexican American, non-Hispanic black, non-Hispanic white, and "other" Hispanic. RESULTS An estimated 16.59 +/- 4.0% (mean +/- SE) of adult female participants who self-identified as Asian, Pacific Islander, Native American, or multiracial (n = 140) had blood mercury levels > or = 5.8 microg/L, and 27.26 +/- 4.22% had levels > or = 3.5 microg/L. Among remaining survey participants (n = 3,497), 5.08 +/- 0.90% had blood mercury levels > or = 5.8 microg/L, and 10.86 +/- 1.45% had levels > or = 3.5 microg/L. CONCLUSIONS Study subjects in NHANES who self-identified as Asian, Pacific Islander, Native American, or multiracial had a higher prevalence of elevated blood mercury than all other racial/ethnic participants in the survey. Future studies should address reasons for the high mercury levels in this group and explore possible interventions for lowering risk of methylmercury exposure in this population.
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Affiliation(s)
- Jane M Hightower
- Department of Internal Medicine, California Pacific Medical Center, San Francisco, California, USA.
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