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“The purpose of this study was to determine the effect of different irrigating solutions on mercury released from dental amalgam. Method and materials: Thirty samples of dental amalgam of similar size were prepared and exposed to a 10-ml solution of either 3% naocl, 17% EDTA, combination of 3% naocl + 17% EDTA solution,2% chlorhexidine, 3% naocl + 2% Chlorhexidine solution, saline solution-control group. For periods of 60 minutes. Mercury concentrations in the solutions were measured by using a cold-vapor atomic absorption Mercury Analyzer System, and the differences between the groups were statistically analyzed. Results-All amalgam samples exposed to 3%naocl , 17% EDTA ,combination of 3% naocl + 17% EDTA , 2% Chlorhexidine solution, 3%naocl + 2%chlorhexidine solution and saline (control) released mercury into solutions. Mercury released was significantly higher in naocl group (3.01) & EDTA + naocl (1.08) as compared to the other test solutions chlorhexidine + naocl (0.6), EDTA (0.29) chlorhexidine (0.24) & saline (0.24) . Chlorhexidine does not show any difference in mercury release with saline (control group).Conclusions. Naocl solutions commonly used for root canal cleaning and shaping cause mercury release from dental Amalgam and may alter its chemo-physical properties as a sealant for root perforations.”

“3923 observations from 2649 dentists were used to perform linear regression using multiple models. Models included individuals with or without imputed BMI, along with either repeated measures or initial observations only. Adjusted covariates included hand temperature, gender, age and BMI. Individuals with rheumatoid arthritis, diabetes, carpal tunnel syndrome (for median nerve models only), or hand temperatures interfering with the accuracy of the instrument were excluded. The main effect of cumulative exposure was found to be significant (p-value <0.05) in median nerve latency and amplitudes but insignificant in ulnar nerve measures. All models but ulnar nerve latency showed a highly significant interaction of cumulative exposure and age (p-value < 0.01).”

“At baseline, individuals with dental amalgam fillings have double the measured urine mercury compared to a control group of persons who have never had amalgam fillings. Removal of amalgam fillings decreases measured urine mercury to levels in persons without amalgam fillings. Although urine mercury levels in our sample are considered by Health Canada to be too low to pose health risks, removal of amalgam fillings reduced the likelihood of self-reported symptom deterioration and increased the likelihood of symptom improvement in comparison to people who retained their amalgam fillings.”

“Mercury (Hg) is neurotoxic, and children may be particularly susceptible to this effect. A current major challenge is identification of children who may be uniquely susceptible to Hg toxicity because of genetic predisposition. We examined the possibility that common genetic variants that are known to affect neurologic functions or Hg handling in adults would modify the adverse neurobehavioral effects of Hg exposure in children. Three hundred thirty subjects who participated as children in the recently completed Casa Pia Clinical Trial of Dental Amalgams in Children were genotyped for 27 variants of 13 genes that are reported to affect neurologic functions and/or Hg disposition in adults. Urinary Hg concentrations, reflecting Hg exposure from any source, served as the Hg exposure index. Regression modeling strategies were employed to evaluate potential associations between allelic status for individual genes or combinations of genes, Hg exposure, and neurobehavioral test outcomes assessed at baseline and for 7 subsequent years during the clinical trial. Among boys, significant modification of Hg effects on neurobehavioral outcomes over a broad range of neurologic domains was observed with variant genotypes for 4 of 13 genes evaluated. Modification of Hg effects on a more limited number of neurobehavioral outcomes was also observed for variants of another 8 genes. Cluster analyses suggested some genes interacting in common processes to affect Hg neurotoxicity. In contrast, significant modification of Hg effects on neurobehavioral functions among girls with the same genotypes was substantially more limited. These observations suggest increased susceptibility to the adverse neurobehavioral effects of Hg among children, particularly boys, with genetic variants that are relatively common to the general human population. These findings advance public health goals to identify factors underlying susceptibility to Hg toxicity and may contribute to strategies for preventing adverse health risks associated with Hg exposure.”

“The effects of human exposure to mercury (Hg) and its compounds in Europe have been the focus of numerous studies that differed in their design, including recruiting different population groups at different levels of exposure and using different protocols and recruitment strategies. The objective of the present study was to review current studies of Hg exposure in Europe, taking into account the potential routes of Hg exposure, actual Hg exposure levels assessed by different biomarkers, and the effects of Hg to Europeans. All published studies from 2000 onward were reviewed, and exposure and effects studies were compared with known Hg levels in environmental compartments by mapping the various population groups studied and taking into account known sources of Hg. A study of the spatial distribution trends confirmed that the highest exposure levels to Hg, mostly as methylmercury (MeHg), are found in coastal populations, which consume more fish than inland populations. Fewer studies addressed exposure to elemental Hg through inhalation of Hg in air and inorganic Hg in food, particularly in highly contaminated areas. Overall, at the currently low exposure levels of Hg prevalently found in Europe, further studies are needed to confirm the risk to European populations, taking into consideration exposure to various Hg compounds and mixtures of stressors with similar end-points, nutritional status, and a detailed understanding of Hg in fish present in European markets.”

“The mercurial forms [inorganic divalent mercury, Hg(II) and methylmercury, CH₃Hg] produce neurological and immune effects as well as hematological and renal alterations. The main route of exposure is through the diet. Consequently, the gastrointestinal mucosa is exposed to these mercurial forms, though the potential toxic effects upon the mucosa are not clear. The present study evaluates the toxicity of Hg(II) and CH₃Hg (0.1–2 mg/L) in an intestinal epithelium model using the differentiated and undifferentiated human Caco-2 cell line.”

“Mercury exposure in pregnancy has been associated with both pregnancy complications and developmental problems in infants. Apart from industrial accidents and contaminated food, mercury exposure is likely to arise from predatory fish consumption, environmental contamination and dental amalgam restorations placed before or during pregnancy. It would be prudent to recommend that pregnant women avoid these potential problems and minimize any risk. The available literature indicates a linear relationship with mercury levels and IQ deficit, and therefore a safe limit of mercury cannot be calculated.”

“Extensive amalgam restorations can be replaced with a variety of treatment options. This clinical study indicates that in such cases directly applied resin based composites offer a reliable and low-cost treatment option, even if dentin is stained by amalgam corrosion products.”

“Geometric means (GM) of whole blood lead (B-Pb), cadmium (B-Cd) and mercury (B-Hg) levelswere 25.3μg/l, 0.55μg/l and 0.21μg/l, respectively. No age-related differences were found for B-Pb and B-Cd levels but a negative correlation with age was observed for B-Hg levels (p=0.04). B-Pb levels in men were significantly higher than in women (GM 29.9μg/l vs. 24.1μg/l). B-Cd was significantly higher in women (GM 0.57μg/l) than in men (0.50μg/l) (p=0.007) and in smokers (GM 1.29μg/l) than in nonsmokers (GM 0.53μg/l) (p=<0.001) and in seniors from Prague (GM 0.60μg/l) compared to those from Teplice (GM 0.43μg/l) (p=<0.001). Seniors with a history of chronic kidney disease, stroke and those using psycho-pharmaceuticals had higher B-Pb levels (p=0.008, 0.04 and 0.05, resp.), seniors diagnosed with atherosclerosis had higher B-Cd levels (p=0.002) and seniors using psycho-pharmaceuticals had higher B-Hg levels (p=0.07). B-Hg levels were also positively correlated with blood albumin levels (p=0.015).”

“Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urinary concentration is a good indicator of poisoning of elemental and inorganic mercury, but organic mercury (e.g. methyl mercury) can be detected easily in feces. Gold nanoparticles (AuNPs) are a rapid, cheap and sensitive method for detection of thymine bound mercuric ions. Silver nanoparticles are used as a sensitive detector of low concentration Hg2+ ions in homogeneous aqueous solutions. Besides supportive therapy, British anti lewisite, dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA. succimer) and dimercaptopropanesulfoxid acid (DMPS) are currently used as chelating agents in mercury poisoning. Natural biologic scavengers such as algae, azolla and other aquatic plants possess the ability to uptake mercury traces from the environment.”