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International Journal of Environmental... Mar 2019Mercury (Hg) has been identified as one of the most toxic nonradioactive materials known to man. Although mercury is a naturally occurring element, anthropogenic mercury... (Review)
Review
Mercury (Hg) has been identified as one of the most toxic nonradioactive materials known to man. Although mercury is a naturally occurring element, anthropogenic mercury is now a major worldwide concern and is an international priority toxic pollutant. It also comprises one of the primary constituents of dental amalgam fillings. Even though dental mercury amalgams have been used for almost two centuries, its safety has never been tested or proven in the United States by any regulatory agency. There has been an ongoing debate regarding the safety of its use since 1845, and many studies conclude that its use exposes patients to troublesome toxicity. In this review, we present in an objective way the danger of dental amalgam to human health based on current knowledge. This dilemma is addressed in terms of an integrated toxicological approach by focusing on four mayor issues to show how these interrelate to create the whole picture: (1) the irrefutable constant release of mercury vapor from dental amalgams which is responsible for individual chronic exposure, (2) the evidence of organic mercury formation from dental amalgam in the oral cavity, (3) the effect of mercury exposure on gene regulation in human cells which supports the intrinsic genetic susceptibility to toxicant and, finally, (4) the availability of recent epidemiological data supporting the link of dental amalgams to diseases such as Alzheimer's and Parkinson.
Topics: Dental Amalgam; Humans; Mercury; United States
PubMed: 30909378
DOI: 10.3390/ijerph16061036 -
Annals of Agricultural and... 2015It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted... (Review)
Review
INTRODUCTION
It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted contaminants and their adverse effect of living organisms has been widely studied in recent decades. Lifestyle and quality of the ambient environment are among these factors which can mainly contribute to the heavy metals exposure in humans.
OBJECTIVE
A review of literature linking heavy metals and the female reproductive system and description of the possible associations with emission and exposure of heavy metals and impairments of female reproductive system according to current knowledge.
RESULTS
The potential health disorders caused by chronic or acute heavy metals toxicity include immunodeficiency, osteoporosis, neurodegeneration and organ failures. Potential linkages of heavy metals concentration found in different human organs and blood with oestrogen-dependent diseases such as breast cancer, endometrial cancer, endometriosis and spontaneous abortions, as well as pre-term deliveries, stillbirths and hypotrophy, have also been reported.
CONCLUSIONS
Environmental deterioration can lead to the elevated risk of human exposure to heavy metals, and consequently, health implications including disturbances in reproduction. It is therefore important to continue the investigations on metal-induced mechanisms of fertility impairment on the genetic, epigenetic and biochemical level.
Topics: Animals; Cadmium; Cricetinae; Environmental Pollutants; Female; Genitalia, Female; Heavy Metal Poisoning; Humans; Lead; Mercury; Metals, Heavy; Mice; Poisoning; Rats; Reproduction
PubMed: 26094520
DOI: 10.5604/12321966.1152077 -
International Journal of Environmental... Jul 2021The intrauterine environment is critical for healthy prenatal growth and affects neonatal survival and later health. Mercury is a toxic metal which can freely cross the... (Review)
Review
The intrauterine environment is critical for healthy prenatal growth and affects neonatal survival and later health. Mercury is a toxic metal which can freely cross the placenta and disrupt a wide range of cellular processes. Many observational studies have investigated mercury exposure and prenatal growth, but no prior review has synthesised this evidence. Four relevant publication databases (Embase, MEDLINE/PubMed, PsycINFO, and Scopus) were systematically searched to identify studies of prenatal mercury exposure and birth weight, birth length, or head circumference. Study quality was assessed using the NIH Quality Assessment Tool, and results synthesised in a narrative review. Twenty-seven studies met the review criteria, these were in 17 countries and used 8 types of mercury biomarker. Studies of birth weight (total = 27) involving populations with high levels of mercury exposure, non-linear methods, or identified as high quality were more likely to report an association with mercury, but overall results were inconsistent. Most studies reported no strong evidence of association between mercury and birth length (n = 14) or head circumference (n = 14). Overall, our review did not identify strong evidence that mercury exposure leads to impaired prenatal growth, although there was some evidence of a negative association of mercury with birth weight.
Topics: Biomarkers; Birth Weight; Diagnostic Tests, Routine; Female; Humans; Infant, Newborn; Maternal Exposure; Mercury; Placenta; Pregnancy
PubMed: 34281082
DOI: 10.3390/ijerph18137140 -
The Science of the Total Environment Sep 2022Global anthropogenic and legacy mercury (Hg) emissions are the main sources of Arctic Hg contamination, primarily transported there via the atmosphere. This review... (Review)
Review
Global anthropogenic and legacy mercury (Hg) emissions are the main sources of Arctic Hg contamination, primarily transported there via the atmosphere. This review summarizes the state of knowledge of the global anthropogenic sources of Hg emissions, and examines recent changes and source attribution of Hg transport and deposition to the Arctic using models. Estimated global anthropogenic Hg emissions to the atmosphere for 2015 were ~2220 Mg, ~20% higher than 2010. Global anthropogenic, legacy and geogenic Hg emissions were, respectively, responsible for 32%, 64% (wildfires: 6-10%) and 4% of the annual Arctic Hg deposition. Relative contributions to Arctic deposition of anthropogenic origin was dominated by sources in East Asia (32%), Commonwealth of Independent States (12%), and Africa (12%). Model results exhibit significant spatiotemporal variations in Arctic anthropogenic Hg deposition fluxes, driven by regional differences in Hg air transport routes, surface and precipitation uptake rates, and inter-seasonal differences in atmospheric circulation and deposition pathways. Model simulations reveal that changes in meteorology are having a profound impact on contemporary atmospheric Hg in the Arctic. Reversal of North Atlantic Oscillation phase from strongly negative in 2010 to positive in 2015, associated with lower temperature and more sea ice in the Canadian Arctic, Greenland and surrounding ocean, resulted in enhanced production of bromine species and Hg(0) oxidation and lower evasion of Hg(0) from ocean waters in 2015. This led to increased Hg(II) (and its deposition) and reduced Hg(0) air concentrations in these regions in line with High Arctic observations. However, combined changes in meteorology and anthropogenic emissions led to overall elevated modeled Arctic air Hg(0) levels in 2015 compared to 2010 contrary to observed declines at most monitoring sites, likely due to uncertainties in anthropogenic emission speciation, wildfire emissions and model representations of air-surface Hg fluxes.
Topics: Air Pollutants; Arctic Regions; Canada; Environmental Monitoring; Mercury
PubMed: 35623517
DOI: 10.1016/j.scitotenv.2022.156213 -
Journal of Trace Elements in Medicine... Sep 2016The brain pathology in autism spectrum disorders (ASD) indicates marked and ongoing inflammatory reactivity with concomitant neuronal damage. These findings are... (Review)
Review
The brain pathology in autism spectrum disorders (ASD) indicates marked and ongoing inflammatory reactivity with concomitant neuronal damage. These findings are suggestive of neuronal insult as a result of external factors, rather than some type of developmental mishap. Various xenobiotics have been suggested as possible causes of this pathology. In a recent review, the top ten environmental compounds suspected of causing autism and learning disabilities were listed and they included: lead, methyl-mercury, polychorinated biphenyls, organophosphate pesticides, organochlorine pesticides, endocrine disruptors, automotive exhaust, polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers, and perfluorinated compounds. This current review, however, will focus specifically on mercury exposure and ASD by conducting a comprehensive literature search of original studies in humans that examine the potential relationship between mercury and ASD, categorizing, summarizing, and discussing the published research that addresses this topic. This review found 91 studies that examine the potential relationship between mercury and ASD from 1999 to February 2016. Of these studies, the vast majority (74%) suggest that mercury is a risk factor for ASD, revealing both direct and indirect effects. The preponderance of the evidence indicates that mercury exposure is causal and/or contributory in ASD.
Topics: Autistic Disorder; Environmental Exposure; Humans; Mercury; Mercury Poisoning; Risk Factors
PubMed: 27473827
DOI: 10.1016/j.jtemb.2016.06.002 -
Frontiers in Bioscience (Elite Edition) Jan 2018Mercury intoxication is a serious public health problem and a worldwide concern. The Minamata Convention on Mercury has been signed by 128 countries and endorsed by the... (Review)
Review
Mercury intoxication is a serious public health problem and a worldwide concern. The Minamata Convention on Mercury has been signed by 128 countries and endorsed by the World Health Organization with the recommendation of promoting the management of epidemiological information. The Central Nervous System is the main target organ for mercury. Symptoms of intoxication include altered motor coordination, visual and tactile dysfunction and paralysis, caused by neurodegeneration with a key role for oxidative damage. Recently, some studies have demonstrated a correlation between mercury intoxication and isoforms of apolipoprotein E (ApoE). In this review, epidemiological data and hypotheses about the possible molecular mechanisms underlying the association between ApoE and mercury intoxication are assessed. Based on the evidence and the neuropathological changes that the presence of ApoE4 and mercury neurotoxicity have in common, we propose a convergent action of both factors. ApoE4 seems to potentiate the damage caused by mercury. Increased knowledge of this interaction using epidemiological and pre-clinical studies is essential to improve prevention strategies to adequately manage intoxicated patients.
Topics: Apolipoproteins E; Humans; Mercury Poisoning; Neurodegenerative Diseases
PubMed: 28930615
DOI: 10.2741/e819 -
Nihon Eiseigaku Zasshi. Japanese... 2018Mercury and its compounds are classified into three main groups: metallic mercury (Hg), inorganic mercury (Hg), and organic mercury (methyl mercury: CHHg, etc.).... (Review)
Review
Mercury and its compounds are classified into three main groups: metallic mercury (Hg), inorganic mercury (Hg), and organic mercury (methyl mercury: CHHg, etc.). Metallic mercury is the only metal that is liquid at ambient temperature and normal pressure, which readily forms an amalgam with other metals. Therefore, mercury has long been used for refining various metals, and mercury amalgam has been used for dental treatment. Mercury has also been used in measuring instruments such as thermometers, barometers and blood pressure monitors, as well as electric appliances such as lighting equipment and dry batteries. Large amounts of metallic mercury are still used in other countries as a catalyst in the production of caustic soda by electrolysis. In addition, mercury compounds have been used in various chemicals such as mercurochrome, agricultural chemicals, and mildew-proofing agents. However, the use of mercury has also caused health problems for people. Minamata disease in Japan is a typical example. Also, since mercury is highly volatile, it is discharged as a product of industrial activities or derived from volcanoes, and it has been concluded on the basis of the findings of the United Nations Environment Program (UNEP) that it is circulating globally. Therefore, with the aim of establishing an internationally legally binding treaty for the regulation of mercury use to reduce risk, an intergovernmental negotiating committee was established in 2009. Japan actively contributed to this negotiation owing to its experience with Minamata disease, which led to the Convention on the regulation of mercury use being discharged as the "Minamata Convention on Mercury" and the treaty came into force on August 16, 2017. In this review, we introduce 1) the Global Mercury Assessment by UNEP; 2) mercury kinetics, exposure assessment and toxicity of different chemical forms; 3) large-scale epidemics of methylmercury poisoning; 4) methylmercury exposure assessment and health survey in whale-eating populations; 5) elemental mercury exposure assessment and health survey of mercury mine workers in China.
Topics: Animals; Environmental Exposure; Environmental Pollutants; Fishes; Global Health; Humans; Mercury Compounds; Mercury Poisoning, Nervous System; Methylmercury Compounds; Occupational Exposure; Risk Assessment
PubMed: 30270289
DOI: 10.1265/jjh.73.258 -
Bosnian Journal of Basic Medical... Jun 2021Mercury is a toxic substance that is commonly used in skin lightening products. Various effects on humans have been observed, which affect both users and non-users. Many... (Review)
Review
Mercury is a toxic substance that is commonly used in skin lightening products. Various effects on humans have been observed, which affect both users and non-users. Many studies reported delayed diagnosis and treatment, even after weeks of hospitalization. The possible reasons are non-specific clinical manifestation and lack of awareness and knowledge regarding chronic mercury intoxication secondary to skin lightening products. A thorough history of mercury exposure is crucial. Physical assessment and relevant supporting tests are indicated to establish a diagnosis. Blood and urine mercury levels are an essential examination for diagnosis and monitoring of the progress and response to treatment. The primary treatment is the discontinuation of the skin lightening products. Chelation therapy is not mandatory and is usually indicated for symptomatic patients. The prognosis depends on the duration of the product use, concentration of mercury in the skin product, and the severity of clinical presentation.
Topics: Algorithms; Chelation Therapy; Cosmetics; Humans; Mercury Poisoning; Skin Pigmentation
PubMed: 32415819
DOI: 10.17305/bjbms.2020.4759 -
Journal of Environmental and Public... 2020This report synthesizes and evaluates published scientific literature on the environmental occurrence and biomagnification of mercury with emphasis on the San Francisco... (Review)
Review
This report synthesizes and evaluates published scientific literature on the environmental occurrence and biomagnification of mercury with emphasis on the San Francisco Bay Area (SFBA), California. Mercury forms various compounds, well known for their toxicity in humans and environmental ecosystems. Elemental mercury is transported and distributed by air, water, and sediments. Through the metabolic processes of algae and bacteria, mercury is converted into organic compounds, such as methylmercury (MeHg), which then bioaccumulates up through trophic levels. In fish, it is found primarily in skeletal muscle, while in humans, the primary target organs are the brain and kidneys. Health concerns exist regarding bioaccumulation of mercury in humans. This paper reviews the known anthropogenic sources of mercury contamination, including atmospheric deposition through aerial transport from coal burning power plants, cement production, and residual contaminants of mercury from gold mining, as well as mercury-containing waste from silver amalgams emitted from dental offices into waterways. Although tools exist for measuring mercury levels in hair, breast milk, urine, blood, and feces in humans, current diagnostic tools are inadequate in measuring total mercury load, including deposited mercury in tissues. Additionally, insufficient attention is being paid to potential synergistic impacts of mercury interaction with multipliers such as lead, cadmium, and aluminum. We provide specific data on methylmercury concentrations at different trophic levels, followed by recommendations for reducing the level of mercury in the SFBA in order to protect the health of humans and other species.
Topics: Animals; Ecosystem; Environmental Monitoring; Environmental Pollutants; Humans; Mercury; Mercury Poisoning; Metals, Heavy; Methylmercury Compounds; San Francisco
PubMed: 33014081
DOI: 10.1155/2020/8184614 -
Current Environmental Health Reports Sep 2015Mercury affects the nervous system and has been implicated in altering heart rhythm and function. We sought to better define its role in modulating heart rate... (Review)
Review
BACKGROUND
Mercury affects the nervous system and has been implicated in altering heart rhythm and function. We sought to better define its role in modulating heart rate variability, a well-known marker of cardiac autonomic function.
DESIGN
This is a systematic review study.
METHODS
We searched PubMed, Embase, TOXLINE, and DART databases without language restriction. We report findings as a qualitative systematic review because heterogeneity in study design and assessment of exposures and outcomes across studies, as well as other methodological limitations of the literature, precluded a quantitative meta-analysis.
RESULTS
We identified 12 studies of mercury exposure and heart rate variability in human populations (ten studies involving primarily environmental methylmercury exposure and two studies involving occupational exposure to inorganic mercury) conducted in Japan, the Faroe Islands, Canada, Korea, French Polynesia, Finland, and Egypt. The association of prenatal mercury exposure with lower high-frequency band scores (thought to reflect parasympathetic activity) in several studies, in particular the inverse association of cord blood mercury levels with the coefficient of variation of the R-R intervals and with low-frequency and high-frequency bands at 14 years of age in the Faroe Islands birth cohort study, suggests that early mercury exposure could have a long-lasting effect on cardiac parasympathetic activity. Studies with later environmental exposures to mercury in children or in adults were heterogeneous and did not show consistent associations.
CONCLUSIONS
The evidence was too limited to draw firm causal inferences. Additional research is needed to elucidate the effects of mercury on cardiac autonomic function, particularly as early-life exposures might have lasting impacts on cardiac parasympathetic function.
Topics: Adolescent; Adult; Autonomic Nervous System; Child; Environmental Exposure; Female; Heart; Heart Rate; Humans; Male; Mercury; Mercury Poisoning, Nervous System; Occupational Exposure; Pregnancy; Prenatal Exposure Delayed Effects
PubMed: 26231507
DOI: 10.1007/s40572-015-0053-0