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Vergara-Murillo F, González-Ospino S, Cepeda-Ortega N, Pomares-Herrera F, Johnson-Restrepo B. Adverse Health Effects and Mercury Exposure in a Colombian Artisanal and Small-Scale Gold Mining Community. TOXICS 2022; 10:723. [PMID: 36548556 PMCID: PMC9782122 DOI: 10.3390/toxics10120723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/17/2022] [Accepted: 11/19/2022] [Indexed: 06/17/2023]
Abstract
The aim of this study was, first of all, to associate the mercury (Hg) concentrations and respiratory functions of the gold miners in the artisanal small-scale gold mining (ASGM) environment in San Martín de Loba, Colombia. We carried out a cross-sectional study using a survey whereby we collected basic demographic information, occupational medical history, and applied two validated questionnaires (Q16 and SF36). We measured Hg levels in all volunteers using direct thermal decomposition-atomic absorption spectrometry. Univariate and bivariate statistical analyses were carried out for all variables, performing logistic regression to assess the effect of ASGM on health outcomes. Volunteers enrolled (n = 124) were between the ages of 20 and 84 years (84% miners and 79% males). No changes were found in the systolic blood pressure, diastolic blood pressure, and heart rate from the ASGM miners, in crude and adjusted statistical analyses. ASGM miners increased 8.91 (95% confidence interval, 1.55-95.70) times the risk of having these than of having neurotoxic effects. Concentrations of total whole blood mercury (T-Hg) in all participants ranged from 0.6 to 82.5 with a median of 6.0 μg/L. Miners had higher T-Hg concentrations than non-miners (p-value = 0.011). Normal and abnormal respiratory spirometry patterns showed significant differences with the physical role and physical function of quality-of-life scales (the (p-value was 0.012 and 0.004, respectively). The spirometry test was carried out in 87 male miners, with 25% of these miners reporting abnormalities. Out of these, 73% presented a restrictive spirometry pattern, and 27%, an obstructive spirometry pattern. The ASGM population had higher Hg concentrations and worse neurotoxic symptomatology than non-miners of the same community.
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Affiliation(s)
- Fredy Vergara-Murillo
- Environmental Chemistry Research Group, School of Exact and Natural Sciences, University Campus of San Pablo, University of Cartagena, Zaragocilla, Carrera 50 No. 24-99, Cartagena 130015, Colombia
- School of Medicine, University of Cartagena, Zaragocilla, Carrera 50 No. 24-99, Cartagena 130015, Colombia
| | | | - Nazly Cepeda-Ortega
- Environmental Chemistry Research Group, School of Exact and Natural Sciences, University Campus of San Pablo, University of Cartagena, Zaragocilla, Carrera 50 No. 24-99, Cartagena 130015, Colombia
| | - Fredy Pomares-Herrera
- School of Medicine, University of Cartagena, Zaragocilla, Carrera 50 No. 24-99, Cartagena 130015, Colombia
| | - Boris Johnson-Restrepo
- Environmental Chemistry Research Group, School of Exact and Natural Sciences, University Campus of San Pablo, University of Cartagena, Zaragocilla, Carrera 50 No. 24-99, Cartagena 130015, Colombia
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Abstract
Mercury (Hg) exists in the environment as inorganic (metallic Hg vapor, mercurous and mercuric salts) or organic (bonded to a structure containing carbon atoms) forms. Neurotoxic effect of Hg is known for years. While the organic form (methylmercury (meHg)) led to the Minamata incidence in Japan and "wonder-wheat" disaster in Iraq, the "mad hatters" and "Danbury shakes" were related to the inorganic elemental form (Hg vapor). Human exposure to toxic Hg continues in the modern world to a large extent by artisanal gold mining, biomass combustion, chloralkali production, and indigenous medicine use to name a few. Heavy industrial use of Hg contaminates air and landfills, affecting the aquatic ecosystem and marine food chain. A detailed social and occupational history with a high index of clinical suspicion is required to not miss this toxic etiology for movement disorders like ataxia, tremor, or myoclonus. In this review, we have discussed the past and present global health impact of Hg from a movement disorder perspective. The connection of Hg with neurodegeneration and autoimmunity has been highlighted. We have also discussed the role of chelating agents and the preventive strategies to combat the neurotoxic effects of Hg in the modern world.
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Guo Z, Chen P, Yosri N, Chen Q, Elseedi HR, Zou X, Yang H. Detection of Heavy Metals in Food and Agricultural Products by Surface-enhanced Raman Spectroscopy. FOOD REVIEWS INTERNATIONAL 2021. [DOI: 10.1080/87559129.2021.1934005] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Zhiming Guo
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Ping Chen
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Nermeen Yosri
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Quansheng Chen
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Hesham R. Elseedi
- Pharmacognosy Division, Department of Medicinal Chemistry, Uppsala University, Biomedical Centre, Uppsala, Sweden
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang, China
| | - Xiaobo Zou
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang, China
| | - Hongshun Yang
- Department of Food Science & Technology, National University of Singapore, Singapore, Singapore
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Shen CY, Weng JC, Tsai JD, Su PH, Chou MC, Wang SL. Prenatal Exposure to Endocrine-Disrupting Chemicals and Subsequent Brain Structure Changes Revealed by Voxel-Based Morphometry and Generalized Q-Sampling MRI. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18094798. [PMID: 33946254 PMCID: PMC8125311 DOI: 10.3390/ijerph18094798] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/23/2021] [Accepted: 04/28/2021] [Indexed: 01/17/2023]
Abstract
Previous studies have indicated that prenatal exposure to endocrine-disrupting chemicals (EDCs) can cause adverse neuropsychiatric disorders in children and adolescents. This study aimed to determine the association between the concentrations of prenatal EDCs and brain structure changes in teenagers by using MRI. We recruited 49 mother–child pairs during the third trimester of pregnancy, and collected and examined the concentration of EDCs—including phthalate esters, perfluorochemicals (PFCs), and heavy metals (lead, arsenic, cadmium, and mercury)—in maternal urine and/or serum. MRI voxel-based morphometry (VBM) and generalized q-sampling imaging (GQI) mapping—including generalized fractional anisotropy (GFA), normalized quantitative anisotropy (NQA), and the isotropic value of the orientation distribution function (ISO)—were obtained in teenagers 13–16 years of age in order to find the association between maternal EDC concentrations and possible brain structure alterations in the teenagers’ brains. We found that there are several specific vulnerable brain areas/structures associated with prenatal exposure to EDCs, including decreased focal brain volume, primarily in the frontal lobe; high frontoparietal lobe, temporooccipital lobe and cerebellum; and white matter structural alterations, which showed a negative association with GFA/NQA and a positive association with ISO, primarily in the corpus callosum, external and internal capsules, corona radiata, superior fronto-occipital fasciculus, and superior longitudinal fasciculus. Prenatal exposure to EDCs may be associated with specific brain structure alterations in teenagers.
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Affiliation(s)
- Chao-Yu Shen
- Institute of Medicine and School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (C.-Y.S.); (J.-D.T.); (P.-H.S.); (M.-C.C.)
- Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Jun-Cheng Weng
- Bachelor Program in Artificial Intelligence, Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan 33302, Taiwan
- Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University and Chang Gung Memorial Hospital at Linkou, Taoyuan 33302, Taiwan
- Department of Psychiatry, Chang Gung Memorial Hospital, Chiayi 613, Taiwan
- Correspondence: (J.-C.W.); (S.-L.W.); Tel.: +886-(3)-2118800 (ext. 5394) (J.-C.W.); +886-(3)-7246166 (ext. 36509) (S.-L.W.)
| | - Jeng-Dau Tsai
- Institute of Medicine and School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (C.-Y.S.); (J.-D.T.); (P.-H.S.); (M.-C.C.)
- Department of Pediatrics, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Pen-Hua Su
- Institute of Medicine and School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (C.-Y.S.); (J.-D.T.); (P.-H.S.); (M.-C.C.)
- Department of Pediatrics, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Ming-Chih Chou
- Institute of Medicine and School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (C.-Y.S.); (J.-D.T.); (P.-H.S.); (M.-C.C.)
- Division of Thoracic Surgery, Department of Surgery, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
| | - Shu-Li Wang
- National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli 350, Taiwan
- Correspondence: (J.-C.W.); (S.-L.W.); Tel.: +886-(3)-2118800 (ext. 5394) (J.-C.W.); +886-(3)-7246166 (ext. 36509) (S.-L.W.)
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Personalized Prevention in Mercury-Induced Amyotrophic Lateral Sclerosis: A Case Report. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10217839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chronic exposure to low levels of mercury is involved in the development of motor neuron diseases (MND). Genetic alterations may have a crucial role in the onset and progression. We presented a case of a TANK-binding kinase 1 (TBK1)-mutated 54-year-old male worker who developed a MND due to chronic mercury exposure at work. He was employed in a chlor-alkali plant in Central Italy. After two years of employment he had acute mercury intoxication with suggestive neurological symptoms and a high urinary level of the metal. Through years, many episodes of intoxication occurred, but he continued to perform the same job and be exposed to mercury. After yet another episode of intoxication in 2013, he showed fasciculations of the upper limbs and trunk, and electromyographic activity patterns were consistent with amyotrophic lateral sclerosis (ALS). In 2016, a genetic test revealed a mutation of TBK1, an ALS-related gene. This case highlights the important role of genetics in personalized occupational medicine. Occupational physicians should use genetic tests to identify conditions of individual susceptibility in workers with documented frequent episodes of mercury intoxication recorded during health surveillance programs to customize prevention measures in the workplace and act before damage appears.
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Piagno H, Afshari R. Mercury from crematoriums: human health risk assessment and estimate of total emissions in British Columbia. Canadian Journal of Public Health 2020; 111:1011-1019. [PMID: 32524506 DOI: 10.17269/s41997-020-00327-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/23/2020] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Mercury occurs in the environment as a result of natural processes and human activities, including when individuals with amalgam dental fillings are cremated. This work aimed to estimate the quantity of mercury emitted to the atmosphere from crematoriums in British Columbia (BC) and assess the human health risk. METHODS A BC-specific emissions factor for mercury from crematoriums was developed and applied to an estimate of the quantity of mercury released annually to the atmosphere from crematoriums. The maximum ground-level mercury vapour concentrations resulting from crematorium emissions were estimated. RESULTS In BC, it is estimated that approximately 1.20 g of mercury is emitted to the atmosphere per body cremated and about 30,000 cremations were conducted in the province in 2016. It is estimated that almost 36 kg of elemental mercury was released to the atmosphere as a result. The maximum estimated peak short-term and long-term average ground-level mercury vapour concentrations associated with crematorium emissions were 0.31 μg/m3 and 7.9 × 10-3 μg/m3 respectively, which are far lower than the reference concentration (hazard quotient of less than 1). CONCLUSION Mercury from crematoriums accounts for more than 7% of total mercury emissions to the atmosphere in BC, but risk assessment found no indication that ground-level exposures to elemental mercury vapour from crematoriums poses a significant risk to human health. If the number of cremations increases, it might reach considerable levels, highlighting the need for developing a national plan similar to other countries.
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Affiliation(s)
- Haley Piagno
- School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada
| | - Reza Afshari
- Division of Occupational and Environmental Health, School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, BC, V6T 1Z3, Canada.
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Wells EM, Kopylev L, Nachman R, Radke EG, Segal D. Seafood, wine, rice, vegetables, and other food items associated with mercury biomarkers among seafood and non-seafood consumers: NHANES 2011-2012. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2020; 30:504-514. [PMID: 32015433 PMCID: PMC7183423 DOI: 10.1038/s41370-020-0206-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/03/2019] [Accepted: 12/23/2019] [Indexed: 05/05/2023]
Abstract
Fish/seafood consumption is a source of mercury; other dietary sources are not well described. This cross-sectional study used National Health and Nutrition Examination Survey (NHANES) 2011-2012 data. Participants self-reported consuming fish/seafood (N = 5427) or not (N = 1770) within the past 30 days. Whole blood total mercury (THg), methylmercury (MeHg), and urinary mercury (UHg) were determined. Diet was assessed using 24 h recall. Adjusted regression models predicted mercury biomarker concentrations with recent food consumption, while controlling for age, sex, education, and race/ethnicity. Geometric mean THg was 0.89 µg/L (95% confidence interval (CI): 0.78, 1.02) (seafood consumers) and 0.31 µg/L (95% CI: 0.28, 0.34) (non-seafood consumers); MeHg and UHg concentrations follow similar patterns. In adjusted regressions among seafood consumers, significant associations were observed between mercury biomarkers with multiple foods, including fish/seafood, wine, rice, vegetables/vegetable oil, liquor, and beans/nuts/soy. Among non-seafood consumers, higher THg was significantly associated with mixed rice dishes, vegetables/vegetable oil, liquor, and approached statistical significance with wine (p < 0.10); higher MeHg was significantly associated with wine and higher UHg was significantly associated with mixed rice dishes. Fish/seafood consumption is the strongest dietary predictor of mercury biomarker concentrations; however, consumption of wine, rice, vegetables/vegetable oil, or liquor may also contribute, especially among non-seafood consumers.
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Affiliation(s)
- Ellen M Wells
- School of Health Sciences, Purdue University, West Lafayette, IN, USA.
- Department of Public Health, Purdue University, West Lafayette, IN, USA.
| | - Leonid Kopylev
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Washington, DC, USA
| | - Rebecca Nachman
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Washington, DC, USA
| | - Elizabeth G Radke
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Washington, DC, USA
| | - Deborah Segal
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Washington, DC, USA
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Louis ED, Ferrer M, Eliasen EH, Gaini S, Petersen MS. Tremor in normal adults: A population-based study of 1158 adults in the Faroe Islands. J Neurol Sci 2019; 400:169-174. [PMID: 30954661 DOI: 10.1016/j.jns.2019.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 02/25/2019] [Accepted: 03/20/2019] [Indexed: 12/27/2022]
Abstract
There are virtually no population-based data on tremor in normal individuals. Using a population-based sample of 1158 normal adults ages 40-98 years in the Faroe Islands, we characterized the extent of normal action tremor across age and gender strata. Participants drew two Archimedes spirals with each hand, and tremor was systematically quantified by a senior movement disorder neurologist using a reliable and valid ordinal rating scale (ratings = 0-3). Tremor was nearly universal - 1145 (98.9%) participants had a total mean spiral score > 0. Older age was associated with more tremor (p < .001) and spiral scores were higher in males than females (p < .001). The proportion of individuals with a spiral rating ≥ 1.5 (i.e., more than mild tremor) was low (1.8% - 8.5%); however, this value reached 19.6% in left-hand spirals of males ≥70 years old. In this population-based study of more than one thousand normal adults, the vast bulk (i.e., 98.9%) had tremor on spiral drawing. In general, the tremor was mild. The proportion of individuals with tremor above the mild range varied across age and gender strata. These extensive data may be used as a gold standard for defining normal levels of tremor within adult populations.
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Affiliation(s)
- Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA; Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA; Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA.
| | - Monica Ferrer
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Eina H Eliasen
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Tórshavn, Faroe Islands
| | - Shahin Gaini
- Infectious Diseases Division, National Hospital Faroe Islands, Tórshavn, Faroe Islands; Department of Infectious Diseases, Odense University Hospital/University of Southern Denmark, Odense, Denmark; Centre for Health Science, Faculty of Health Sciences, University of the Faroe Islands, Tórshavn, Faroe Islands
| | - Maria Skaalum Petersen
- Department of Occupational Medicine and Public Health, The Faroese Hospital System, Tórshavn, Faroe Islands; Centre for Health Science, Faculty of Health Sciences, University of the Faroe Islands, Tórshavn, Faroe Islands
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Association between catatonia and levels of hair and serum trace elements and minerals in autism spectrum disorder. Biomed Pharmacother 2019; 109:174-180. [DOI: 10.1016/j.biopha.2018.10.051] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/05/2018] [Accepted: 10/09/2018] [Indexed: 12/28/2022] Open
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Calabrese EJ, Iavicoli I, Calabrese V, Cory-Slechta DA, Giordano J. Elemental mercury neurotoxicity and clinical recovery of function: A review of findings, and implications for occupational health. ENVIRONMENTAL RESEARCH 2018; 163:134-148. [PMID: 29438899 DOI: 10.1016/j.envres.2018.01.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 01/16/2018] [Accepted: 01/17/2018] [Indexed: 06/08/2023]
Abstract
This paper assessed approximately 30 studies, mostly involving occupationally exposed subjects, concerning the extent to which those who developed elemental mercury (Hg)-induced central and/or peripheral neurotoxicities from chronic or acute exposures recover functionality and/or performance. While some recovery occurred in the vast majority of cases, the extent of such recoveries varied considerably by individual and endpoint. Factors accounting for the extensive inter-individual variation in toxicity and recovery were not specifically assessed such as age, gender, diet, environmental enrichment, chelation strategies and dose-rate. While the data indicate that psychomotor endpoints often show substantial and relatively rapid (i.e., 2-6 months) recovery and that neuropsychological endpoints display slower and less complete recovery, generalizations are difficult due to highly variable study designs, use of different endpoints measured between studies, different Hg exposures based on blood/urine concentrations and Hg dose-rates, the poor capacity for replicating findings due to the unpredictable/episodic nature of harmful exposures to elemental Hg, and the inconsistency of the initiation of studies after induced toxicities and the differing periods of follow up during recovery periods. Finally, there is strikingly limited animal model literature on the topic of recovery/reversibility of elemental Hg toxicity, a factor which significantly contributes to the overall marked uncertainties for predicting the rate and magnitude of recovery and the factors that affect it.
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Affiliation(s)
- Edward J Calabrese
- Department of Environmental Health Sciences, University of Massachusetts, Morrill I, N344, Amherst, MA 01003, USA.
| | - Ivo Iavicoli
- Department of Public Health, University of Naples Federico II, Via S. Pansini 5, Naples 80131, Italy.
| | - Vittorio Calabrese
- Department of Biomed & Biotech Sciences, School of Medicine, University of Catania, Via Santa Sofia 97, Catania 95125, Italy.
| | - Deborah A Cory-Slechta
- Environmental Medicine, Pediatrics & Public Health Sciences, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - James Giordano
- Department of Neurology and Biochemistry, and Neuroethics Studies Program-Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington, D.C. 20057, USA.
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Fields CA, Borak J, Louis ED. Persistence of mercury-induced motor and sensory neurotoxicity: systematic review of workers previously exposed to mercury vapor. Crit Rev Toxicol 2017; 47:845-866. [PMID: 28722535 PMCID: PMC5962347 DOI: 10.1080/10408444.2017.1342599] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 05/16/2017] [Accepted: 06/11/2017] [Indexed: 10/19/2022]
Abstract
Elemental mercury (Hg0) is a well-recognized neurotoxicant, but it is uncertain whether and for how long its neurotoxicity persists. Among studies that evaluated previously-exposed workers, only one examined workers during and also years after exposure had ceased. The objective of this review is to create a series of 'synthetic' longitudinal studies to address the question of persistence of Hg0 neurotoxicity in occupationally exposed workers. We systematically reviewed studies describing objective motor and sensory effects in previously-exposed mercury workers. Data from physical examination (PE), neurobehavioral (NB) tests, and electrophysiological studies (EPS) were extracted into structured tables and examined for their consistency and dose-relatedness and then compared with the corresponding results from studies of currently exposed workers. We identified six cohorts that described neurological findings in 1299 workers, examined an average of 4.8-30 years after the cessation of exposure. Historical group mean UHg levels ranged from 23 to >500 μg/L, with UHg levels >6000 μg/L in some individuals. Overall, few findings were significant; most were inconsistent across the previous-exposure studies, and in comparisons between studies of previously and currently exposed workers. The results of this systematic review indicate that Hg0-related neurotoxic effects detectable on PE, NB testing, and EPS are substantially reversed over time. To the extent that such effects do persist, they are reported principally in workers who have had very high-dose exposures. In addition, based on the limited available data, those effects reported to persist have been described as having little or no functional significance.
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Affiliation(s)
- Cheryl A. Fields
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, Connecticut, USA
| | - Jonathan Borak
- Departments of Medicine and Epidemiology & Public Health, Yale School of Medicine, New Haven, Connecticut, USA
| | - Elan D. Louis
- Department of Neurology, Yale School of Medicine, and Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, Connecticut, USA
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