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Torrey EF, Simmons W. Mercury and Parkinson's Disease: Promising Leads, but Research Is Needed. PARKINSON'S DISEASE 2023; 2023:4709322. [PMID: 37744289 PMCID: PMC10517869 DOI: 10.1155/2023/4709322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023]
Abstract
Environmental toxicants are thought to play a major role in the pathogenesis of Parkinson's disease. In reviewing the literature on heavy metals known to be toxicants, we noted several recent studies on mercury suggesting a possible role in the etiology of some cases of this disease. We therefore undertook a review of this association, focusing especially on peer-reviewed articles to avoid the bias inherent in much of the literature regarding mercury. For most people, our contemporary exposure to mercury comes from dental amalgam tooth restorations and from eating fish contaminated with mercury. In both cases, mercury is known to get into the brain in utero and at all ages. It remains in the brain for many years and is known to produce permanent neuropsychological deficits. Mercury toxicity can produce tremors and other Parkinsonian clinical symptoms. It can also produce neurochemical and neuropathological changes similar to those found in Parkinson's disease, including the loss of dopamine neurons, degeneration of tubulin and axons, dysfunction of mitochondria, and the aggregation of alpha-synuclein. Relatively few studies have assessed mercury in parkinsonian patients, but almost all reported a statistically significant association. Published studies suggest some promising leads in the relationship between mercury exposure and Parkinson's disease. However, studies of patients are relatively few, and the need for research is clear. A search of Parkinsonian research studies currently funded by the US National Institutes of Health, Parkinson's Foundation, and the Michael J Fox Foundation yielded no studies on mercury. We believe such studies should be supported.
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Affiliation(s)
- E. Fuller Torrey
- The Stanley Medical Research Institute, 9800 Medical Center, Suite C-050, Rockville, MD 20850, USA
| | - Wendy Simmons
- The Stanley Medical Research Institute, 9800 Medical Center, Suite C-050, Rockville, MD 20850, USA
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Kadry MO, Abdel Megeed RM. Ubiquitous toxicity of Mercuric Chloride in target tissues and organs: Impact of Ubidecarenone and liposomal-Ubidecarenone STAT 5A/ PTEN /PI3K/AKT signaling pathways. J Trace Elem Med Biol 2022; 74:127058. [PMID: 35952450 DOI: 10.1016/j.jtemb.2022.127058] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 06/26/2022] [Accepted: 08/02/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Mercuric chloride (HgCl3) is categorized as class II B hazardous metal that is present in many occupational and environmental conditions. In the meantime, Hg exists in the environment in such an abundant manner, it is virtually impossible for humans to avoid exposure to different forms of Hg. In addition to environmental exposure, individuals may be exposed to Hg from dental amalgams, medicinal treatments and dietary sources. Nevertheless, Liposomal drug delivery system is a promising era in the field of Nano-medicine and have the advantageous of increasing drug bioavailability and retention phenomena in addition to targeting organ for all mentioned the present study was designed to investigate the hypothesis that messenger RNA gene expression of Signal transducer and activator of transcription- 5 A (STAT-5A), Phosphatase and tensin homolog (PTEN), phosphoinositol kinase (PI3K) and alpha serine/threonine-protein kinase (AKT) can trigger HgCl3 induced nephrotoxicity post Ubidecarenone and liposomal Ubidecarenone therapy. METHODS HgCl3 toxicity was induced in rats via a dose of 5 mg/kg BW for one week followed by Ubidecarenone and liposomal Ubidecarenone therapy in a dose of 10 & 3 mg/kg BW for one month, respectively. Then kidney function tests, Glutathione and gene expression for PI3K, AKT, PTEN and STAT-5A was investigated. RESULTS HgCl3 intoxication significantly up regulated PI3K, AKT, PTEN and STAT-5A signaling pathways meanwhile, Ubidecarenone and liposomal- Ubidecarenone treatment significantly reduced PI3K, AKT, PTEN and STAT-5A gene expression post HgCl3 intoxication with the liposomal regimen revealing the most significant impact. Furthermore, renal toxicity was confirmed via monitoring urea and creatinine which were modulated post Ubidecarenone and liposomal-Ubidecarenone treatment. Wide evidence declared that mercuric S-conjugates of small endogenous thiols (such as Hcy, NAC and Cys) are probably the main transportable forms of Hg2+ to the kidneys thus reduced glutathione was investigated which reflected a significant down regulation post Hgcl3 toxicity. CONCLUSION liposomal drug delivery system including liposomal-Ubidecarenone can be considered as a prospective candidate for treating HgCl3 renal toxicity via modulating STAT-5A, PTEN, PI3K and AKT signaling pathways and via increasing retention time, bioavailability, shielding from macrophage recognition and targeting organs.
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Affiliation(s)
- Mai O Kadry
- National Research Center, Therapeutic Chemistry Department, Al Bhoouth Street, Cairo, Egypt.
| | - Rehab M Abdel Megeed
- National Research Center, Therapeutic Chemistry Department, Al Bhoouth Street, Cairo, Egypt
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Spiller HA, Hays HL, Casavant MJ. Rethinking treatment of mercury poisoning: the roles of selenium, acetylcysteine, and thiol chelators in the treatment of mercury poisoning: a narrative review. TOXICOLOGY COMMUNICATIONS 2021. [DOI: 10.1080/24734306.2020.1870077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Affiliation(s)
- Henry A. Spiller
- Central Ohio Poison Center, Nationwide Children’s Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Hannah L. Hays
- Central Ohio Poison Center, Nationwide Children’s Hospital, Columbus, OH, USA
- Departments of Emergency Medicine and Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Marcel J. Casavant
- Central Ohio Poison Center, Nationwide Children’s Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
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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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Abstract
Although there has been an increased interest on premature ejaculation in the recent years, our understanding regarding the disorders of retrograde ejaculation, painful ejaculation and hematospermia remain limited. All three of these conditions require a keen clinical acumen and willingness to engage in thinking outside of the standard established treatment paradigm. The development of novel investigational techniques and treatments has led to progress in the management of these conditions symptoms; however, the literature almost uniformly is limited to small series and rare randomised trials. Further investigation and randomised controlled trials are needed for progress in these often challenging cases.
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Mechanisms involved in the transport of mercuric ions in target tissues. Arch Toxicol 2016; 91:63-81. [PMID: 27422290 DOI: 10.1007/s00204-016-1803-y] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 07/07/2016] [Indexed: 01/16/2023]
Abstract
Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells.
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Lucchini RG, Hashim D. Tremor secondary to neurotoxic exposure: mercury, lead, solvents, pesticides. HANDBOOK OF CLINICAL NEUROLOGY 2015; 131:241-249. [PMID: 26563793 DOI: 10.1016/b978-0-444-62627-1.00014-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Lead, mercury, solvents, and pesticide exposures are common in certain occupations and may cause nervous system dysfunction. Tremors may be the herald manifestation among a constellation of acute toxicity signs and symptoms. However, since tremors may also be the only sign on clinical presentation and since tremors also occur in other diseases, relating tremors to a specific occupational exposure can be challenging. Diagnosis of tremor etiology must be based on other findings on physical exam, laboratory results, and/or imaging. Discerning whether the tremor resulted from the occupational environment versus other etiologies requires knowledge of potential exposure sources, additional detail in history taking, and support of other health and industrial professionals. Reduction or removal from the exposure source remains the key first step in treating patients suffering from tremor that had resulted from occupational exposure toxicity.
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Affiliation(s)
- Roberto G Lucchini
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Unit of Occupational Medicine, Department of Medical Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy.
| | - Dana Hashim
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Abstract
Of the known elements, nearly 80% are either metals or metalloids. The highly reactive nature of most metals result in their forming complexes with other compounds such oxygen, sulfide and chloride. Although this reactivity is the primary means by which they are toxic, many metals, in trace amounts, are vital to normal physiological processes; examples include iron in oxygen transport, manganese and selenium in antioxidant defense and zinc in metabolism. With these essential metals toxicity occurs when concentrations are either too low or too high. For some metals there are no physiological concentrations that are beneficial; as such these metals only have the potential to cause toxicity. This chapter focuses on four of these: arsenic, mercury, lead and thallium.
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Bridges CC, Zalups RK. Transport of inorganic mercury and methylmercury in target tissues and organs. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2010; 13:385-410. [PMID: 20582853 PMCID: PMC6943924 DOI: 10.1080/10937401003673750] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Owing to the prevalence of mercury in the environment, the risk of human exposure to this toxic metal continues to increase. Following exposure to mercury, this metal accumulates in numerous organs, including brain, intestine, kidneys, liver, and placenta. Although a number of mechanisms for the transport of mercuric ions into target organs were proposed in recent years, these mechanisms have not been characterized completely. This review summarizes the current literature related to the transport of inorganic and organic forms of mercury in various tissues and organs. This review identifies known mechanisms of mercury transport and provides information on additional mechanisms that may potentially play a role in the transport of mercuric ions into target cells.
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Affiliation(s)
- Christy C Bridges
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia 31207, USA.
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Echeverria D, Woods JS, Heyer NJ, Rohlman DS, Farin FM, Bittner AC, Li T, Garabedian C. Chronic low-level mercury exposure, BDNF polymorphism, and associations with cognitive and motor function. Neurotoxicol Teratol 2009; 27:781-96. [PMID: 16301096 DOI: 10.1016/j.ntt.2005.08.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Revised: 08/22/2005] [Accepted: 08/22/2005] [Indexed: 11/27/2022]
Abstract
Potential cognitive and motor effects from exposure to elemental mercury (Hg(0)) were examined in the presence and absence of a polymorphism (Val66Met) in brain-derived neurotrophic factor (BDNF). A group of 194 male dentists (DDs) and 233 female dental assistants (DAs) were occupationally exposed to mercury and had no history of kidney or nervous system disorders. Acute exposure was measured using spot urinary Hg (HgU) concentrations (average 3.32 and 1.98 microg/l, respectively) and indices of chronic occupational exposure (26.3 and 14.9 years, respectively, weighted for historical exposures). The BDNF status was 68% and 66% wild type, 26% and 30% single substitution, and 5% and 4% full mutation for DDs and DAs, respectively. DDs and DAs were evaluated separately. Regression analyses controlled for age, premorbid intelligence, alcohol consumption, and education. Statistically significant adverse associations with HgU (p<.05) were found for nine measures among DDs (Digit Span (Forward), Digit and Spatial Span(Backward), Visual Reproduction, Finger Tapping(Dominant, Alternate, and Alternate Partialed), Hand Steadiness, and Tracking), and eight measures among DAs (Digit Span(Forward), Visual Reproduction, Pattern Discrimination(Rate), Symbol Digit(Rate), Trailmaking B, Finger Tapping(Dominant and Alternate Partialed), and Hand Steadiness). The BDNF status was associated with four measures in DDs and three measures in DAs. Joint effects were found for Finger Tapping(Alternate and Alternate Partialed) in DDs and Hand Steadiness and Trailmaking B in DAs. Joint effects were additive in all cases. Performance on verbal intelligence and reaction time were not associated with either HgU or BDNF status. A test of threshold effect for the association of Hand Steadiness with HgU demonstrated no lower boundary in both DDs and DAs. No associations were observed with estimates of chronic mercury exposure. Our findings are applicable to exposure levels of the general population and identify a potentially vulnerable group with a BDNF polymorphism.
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Affiliation(s)
- Diana Echeverria
- Battelle Centers for Public Health Research and Evaluation, Seattle, WA 98109, USA.
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Affiliation(s)
- John W Osborne
- University of Colorado, Health Sciences Center, Denver, CO, USA
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Haas NS, Shih R, Gochfeld M. A patient with postoperative mercury contamination of the peritoneum. JOURNAL OF TOXICOLOGY. CLINICAL TOXICOLOGY 2003; 41:175-80. [PMID: 12733856 DOI: 10.1081/clt-120019134] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
CASE REPORT Peritoneal exposure to mercury has been rarely reported and long-term consequences of this type of exposure have not been documented. We report the clinical course of a patient who has survived almost eight years with a massive intraperitoneal load of mercury. She has suffered formication, pruritus, fatigue, irritiability, insomnia, alopecia, dizziness, a gait disturbance, loss of balance and multiple falls, abdominal pain, choking, and headaches. Two courses of chelation with dimercaptosuccinic acid using the standard protocol were undertaken, resulting in increased daily excretion, but without demonstrable objective or subjective benefit or lasting effect. She had multiple medical problems before the mercury intoxication, which complicates the attribution of all her problems to mercury intoxication. It is of particular interest that the patient survived and did not suffer any marked cognitive deterioration. She died in 2002 shortly after being diagnosed with lung cancer and declaring that she would fight it. Phasing out of mercury-weighted tubes is recommended.
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Affiliation(s)
- Nelson S Haas
- North Country Occupational Medicine, Newport, Vermont, USA
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Bluhm R, Branch RA. Clinical problems interpreting mercury levels. Experience from mercury exposed chloralkali workers. Int Arch Occup Environ Health 1996; 68:421-4. [PMID: 8891779 DOI: 10.1007/bf00377863] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- R Bluhm
- OccuPatient Medical Services, Nashville, TN 37227-1356, USA
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Bohets HH, Van Thielen MN, Van der Biest I, Van Landeghem GF, D'Haese PC, Nouwen EJ, De Broe ME, Dierickx PJ. Cytotoxicity of mercury compounds in LLC-PK1, MDCK and human proximal tubular cells. Kidney Int 1995; 47:395-403. [PMID: 7723229 DOI: 10.1038/ki.1995.52] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Six mercury compounds [HgCl2 (MC), Hg(CH3COO)2 (MA), Hg(NO3)2 (MN), C2H5HgSC6H4COONa (EMT), C6H5HgOCOCH3 (PMA) and CH3CIHg (MMC)] were studied using two kidney cell lines (MDCK and LLC-PK1), primary cultures of human proximal tubular cells (hPTC) and nonrenal cell lines (SAOS and Hep G2). Cell damage was measured with four different tests: neutral red uptake, mitochondrial dehydrogenase activity (MTT conversion), thymidine incorporation and protein content. Relative toxicity was established by the determination of the concentration of test compound inducing a 50% reduction of the parameter considered (EC50 value). Two groups could be distinguished: PMA, EMT and MMC are one order of magnitude more toxic than MC, MN and MA. Cellular uptake was measured by the HPLC-hybrid generation AAS after 24 hours treatment with 1.5 microM MC, MMC, PMA or EMT in MDCK cells, revealing Hg concentrations of 42.8 +/- 2.5 ng/mg protein for MC, 596.9 +/- 87.8 ng/mg protein for MMC, 269.8 +/- 75.7 ng/mg protein for PMA and of 115.9 +/- 25.2 ng/mg protein for EMT. Cytotoxicity was positively correlated with cellular uptake. The effect of the cellular GSH content on the toxicity of mercury was studied using the GSH synthesis inhibitor L-buthionine sulfoximine (BSO). In all cases an enhanced cytotoxicity was observed after BSO treatment. 2-Oxo-4-thiazolidine carboxylic acid (OTC) was used as a substrate for the GSH synthesis. Although OTC did not enhance the GSH content, the cytotoxicity of MC, MN and MA decreased significantly, no changes were observed for the other mercurials.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H H Bohets
- Division of Toxicology, Instituut voor Hygiëne en Epidemiologie, Brussels, Belgium
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Abstract
This review aims at discussing the questions raised by the hydrocarbon-related chronic nephropathy and its possible consequence, the hydrocarbon-related chronic renal failure. It has been attempted to adopt the point of view of the clinician. Therefore, the most important part of the review is devoted to a presentation and an analysis of the available data on humans. The main features of the available studies on human subjects are presented, their conclusions discussed in the light of the possible methodological flaws, and practical conclusions drawn. After a discussion of the main difficulties encountered for selecting the suitable exposure indicator, the studies are discussed in order of decreasing quality of the study design (cohort, case-control, cross-sectional studies, and the case reports). It is concluded that a great deal of controversies about chronic hydrocarbon-related nephropathy is explained by differences in the study design and that hydrocarbon-induced nephropathy is probably more than a mere hypothesis, although a causal relationship has not yet been proven. Finally, some practical consequences for dealing with a hydrocarbon-exposed patient diagnosed with a kidney disease and the need for further research are discussed.
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Affiliation(s)
- P Hotz
- Institut für Sozial und Präventivmedizin, Zürich, Switzerland
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Bluhm RE, Bobbitt RG, Welch LW, Wood AJ, Bonfiglio JF, Sarzen C, Heath AJ, Branch RA. Elemental mercury vapour toxicity, treatment, and prognosis after acute, intensive exposure in chloralkali plant workers. Part I: History, neuropsychological findings and chelator effects. Hum Exp Toxicol 1992; 11:201-10. [PMID: 1352115 DOI: 10.1177/096032719201100308] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mercury poisoning occurred after the acute, prolonged exposure of 53 construction workers to elemental mercury. Of those exposed, 26 were evaluated by clinical examination and tests of neuropsychological function. Patients received treatment with chelation therapy in the first weeks after exposure. Eleven of the patients with the highest mercury levels were followed in detail over an extended period. Observations included the evaluation of subjective symptoms of distress, using the 'Symptom Check List 90-Revised' (SCL-90R) and tests of visual-motor function such as 'Trailmaking Parts A and B', 'Finger Tapping', 'Stroop Colour Word Test' and 'Grooved Pegboard.' On day 85 +/- 11 (mean +/- s.d.) after exposure, these 11 men again received either 2,3-dimercaptosuccinic acid (DMSA) or N-acetyl-D, L-penicillamine (NAP) in a short-term study designed to compare the potential to mobilize mercury and the incidence of drug-induced toxicity of these two chelating agents. Rapidly resolving metal fume fever was the earliest manifestation of symptoms. CNS symptoms and abnormal performance on neuropsychological tests persisted over the prolonged period of follow-up. There were significant correlations between neuropsychological tests and indices of mercury exposure. Serial mercury in the blood and urine verified the long half-life and large volume of distribution of mercury. Chelation therapy with both drugs resulted in the mobilization of a small fraction of the total estimated body mercury. However, DMSA was able to increase the excretion of mercury to a greater extent than NAP. These observations demonstrate that acute exposure to elemental mercury and its vapour induces acute, inorganic mercury toxicity and causes long-term, probably irreversible, neurological sequelae.
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Affiliation(s)
- R E Bluhm
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232-6602
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