• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.597-608
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• 1994

This study was conducted to evaluate the relationships between the environmental exposure and biological monitoring among workers exposed to metallic mercury We interviewed each workers to get the medical history including previous hazardous occupational history. We measured the respiration rate and tidal volume of each worker in order to calculate the 8-hour inhaled mercury of workers. And we wafted to evaluate the effect of exposure duration to mercury concentrations in blood and urine as biologic exposure indices of metallic mercury. The regression and correlation analysis were done to the relationships of 8-hour inhaled mercury and mercury in blood and urine. The results were as follows; 1. The subjects were 35 fluorescent lamp manufacturing workers. The mean age of subjects was .24.8 years old, and the mean work careers of workers was 1.19 years. 89% of the total was consisted man. 2. The correlation coefficients between 8-hour inhaled mercury and mercury in blood and urine were higher than that of only considered air mercury concentration. 3. The correlation coefficients of 8-hour inhaled mercury and mercury in blood and urine were above 0.9 in workers who had exposed to mercury more than 1 year 4. The R-square value and -value of regression analysis between the 8-hour inhaled mercury and mercury in blood and urine was also higher in workers who had exposed to mercury over 1 year than in workers who had less than 1 year working experience. The important results of this study were that relationships between the 8hr-inhaled mercury and mercury in blood and urine was very high than that with air mercury concentration only. And the results were very apparent when considering workers 1 year or more. Therefore we concluded that the work career and respiratory volume of each individuals should be considered in evaluation the, results of biological monitoring of workers exposed to metallic mercury.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.6
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• pp.413-420
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• 2002

Mercury is one of the most frequently used heavy metal in dental clinic. Mercury poisoning rises up when someone is exposed to mercury chronically. In 1818, Amalgam was used for dental restorative procedure, and after then study about mercury toxicity has begun. Clinical signs of mercury toxicity in oral & maxillofacial area were increases of salivation, metallic taste, swelling and pain of tongue, redness and ulceration of oral mucosa, and increased mobility and loss of teeth. After we injected mercury($HgCl_{2}$) into intraperitoneum of rat, studied about histopathological changes of submandibular gland cell. Experimental group was divided into two groups by amount of mercury. (Group 1 was 0.5mg/Kg of mercury injection, group 2 was 1.0mg/Kg of mercury injection.) 1. After 3days of intraperitoneal injection, black granules were observed at macrophage cell in both group. In group 2, author found hyperchromatism of nucleus, and vacuolization of cellular matrix and nucleus of acinar cell. 2. After 1week of intraperitoneal injection, author found severe vacuolization of nucleus and cellular matrix, and irregular granules around nuclear membrane at mucous cell and serous cell in both group. Vacuolization of nucleus and cellular matrix was seen at duct cell in group 2. 3. After 2weeks of intraperitoneal injection, author could found severe vacuolization of cellular matrix, and sometimes nucleus was positioned in central area of cellular matrix at mucous and serous cell in both group. Vacuolization of nucleus and cellular matrix was found at vascular endothelial cell in group 2. 4. After 4weeks of intraperitoneal injection, destruction and distortion of gland cells were distinct. Vacuolization and destruction of nucleus and cellular matrix was found at duct cell in group 2. After intraperitoneal injection of mercury, we found equanimity of mercury and destruction of cellular matrix at serous cell, mucous cell, and duct cell of submandibular gland. So, we thought that metallic taste of mercury poisoning patient would be due to excretion of saliva containing mercury.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.723-728
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• 1999

Pulmonary embolism from metallic mercury is rare. It may occur after a deliberate intravenous injection of mercury as a suicide gesture, in the presence of drug abuse or severe psychiatric disturbance, with the hope of increasing athletic and sexual performance, and accidentally during right heart catheterization while sampling blood with mercury containing syringes. We have experienced the first case of pulmonary embolism associated with intravenous mercury injection in Korea. The blood mercury level remain elevated within the toxic range to date. This may be due to the continued absorption of embolized mercury. Multifocal areas of patchy perfusion defects are in both upper lung fields on perfusion scan of lung. Few of the abnormalities of respiratory or renal function reported previously were demonstrated. We report the case of a young male patient presenting with a clinical picture of pulmonary embolism, in whom widespread deposit of metallic mercury were demonstrated throughout both lungs and elsewhere in the body.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.917-924
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• 2010

The practicability of transgenic tobacco engineered to express bacterial native mercuric reductase (MerA), responsible for the transport of $Hg^{2+}$ ions into the cell and their reduction to elemental mercury ($Hg^0$), without any codon modification, for phytoremediation of mercury pollution was evaluated. Transgenic tobacco plants reduce mercury ions to the metallic form; take up metallic mercury through their roots; and evolve the less toxic elemental mercury. Transformed tobacco produced a large amount of merA protein in leaves and showed a relatively higher resistance phenotype to $HgCl_2$ than wild type. Results suggest that the integrated merA gene, encoding mercuric reductase, a key enzyme of the bacterial mer operon, was stably integrated into the tobacco genome and translated to active MerA, which catalyzes the bioconversion of toxic $Hg^{2+}$ to the least toxic elemental $Hg^0$, and suggest that MerA is capable of reducing the $Hg^{2+}$, probably via NADPH as an electron donor. The transgenic tobacco expressing merA volatilized significantly more mercury than wild-type plants. This is first time we are reporting the expression of a bacterial native merA gene via the nuclear genome of Nicotiana tabacum, and enhanced mercury volatilization from tobacco transgenics. The study clearly indicates that transgenic tobacco plants are reasonable candidates for the remediation of mercurycontaminated areas.

• Journal of Oral Medicine and Pain
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• v.9 no.1
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• pp.29-33
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• 1984

Dental mercury was injected accidentally to left upper buccal mucosa of a 16-year-old girl by charlatan in order to anesthetize a tooth for extraction; thereafter,injected elemental mercury was almost removed by drug adimnistration and surgical operations.One year have passed, still, there are many scaffered small radiopaque white globular cimages in dental, maxillo-facial, and chest radiographs. Redish swollen gingiva and mobility of left upper central incisor which is adjacent to mercury injection site are oral manifestations in this mercury poisoning case. Recently, the patient complains of metallic taste, gastric discomfort and abdominal pain which are thought to be symptoms of mercury poisoning, but there seems to be no serious sequelae now.

• Journal of Preventive Medicine and Public Health
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• v.45 no.6
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• pp.344-352
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• 2012

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety.

• Safety and Health at Work
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• v.2 no.2
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• pp.176-182
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• 2011

Objectives: Previous investigations have presented some evidence of late cognitive effects in dental personnel exposed to metallic mercury. We wanted to examine if Norwegian dentists have an increased prevalence of symptoms consistent with neurological and/or cognitive malfunction. Methods: The study group consisted of 406 dentists from central Norway and 217 controls from the general population, all under the age of 70. They had responded to a standardised postal questionnaire (Euroquest) inquiring about seven symptoms in regard to neurology, psychosomatics, memory, concentration, mood, sleep disturbances, and fatigue. A score was calculated for each symptom based on 4 to 15 single questions scored on a scale from 1 (seldom or never) to 4 (very often). Results: The dentists and controls had a participation rate of 57.2 % and 42.9 % respectively. The dentists reported no more cognitive symptoms than the controls, with low average symptom scores from 1.16 for neurological symptoms in males to 1.73 for fatigue in females. Corresponding figures for the controls were 1.22 and 1.77. There were a total of 1.2 % of the dentists and 1.8 % of the controls who reported having three or more of the seven symptoms "often" or more frequently. Conclusion: Norwegian dentists do not report more cognitive and neurological symptoms than controls from the general population.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2678-2683
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• 2007

The interaction between metal molecules and liquid metal molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand behaviors of the cluster on metallic surface in collision process. Lennard-Jones potential had been used as intermolecular potential, and only attraction 때 d repulsion had been used for the behavior of the cluster on the metal surface. As results, the behavior of the cluster was so much influenced by the cluster of liquid metal temperature and function of molecules forces, such as attraction and repulsion, in the collision progress. These results of simulation will be the foundation for the micro fabrication manufacturing by using spray application technology.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.215-224
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• 1989

Electrochemical reductions of $trans-[Co(en)_2X_2](ClO_4)_n$ (where X is cyanide, nitrite, ammonia, and isothiocyanate) were investigated by cyclic voltammetry and polarography at mercury and glassy carbon electrode. $trans-[Co(en)_2(CN)_2]ClO_4$ was reduced to Co(II) complex followed by adsorption to the mercury electrode. Cyanide ion was not released from the reduced Co(II) complex but the cyanide and (en) were released after the reduction to metallic cobalt. The other complexes except $trans-[Co(en)_2(CN)_2]ClO_4$ were reduced to cobalt(II) complexes followed by release of monodendate ligand, and (en) was released at the reduction step to metallic cobalt. $trans-[Co(en)_2(NO_2)_2]ClO_4$ was reduced to cobalt(Ⅱ) complex, and $NO_2^-$ ion was released followed by electroreduction through ECE mechanism at pH 2. On glassy carbon electrode, all complexes of Co(III) were reduced to Co(II) complexes with irreversible one-electron diffusion controlled reaction in which (en) was not released at this step. Increasing absorption wave number of complexes caused to negative shift of peak potential.

• Conservation Science in Museum
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• v.3
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• pp.65-69
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• 2001

Scientific analysis are carried on gilded ornamental shoes, which have been excavated from tomb No 1. and No 4. in Beopcheon-ri, Wonju dated from Baekje Period. This object is a very important because it provides valuable information on the development of metal-making techniques of that period. Thus, this article illustrates the investigation conducted to reveal how the object was created using what materials and techniques. Instead of the spikes-attached to the bottom plate of the object-that couldn't be sampled, a sample of a decorative rivet showing a similar structure to the spikes-attached to the other parts of the shoes-was prepared for a cross-section examination. Using radiography and microscopes, it was found that the head of a spike was placed and then punched to the gilded plate, so it can be held to the shoes. Under the SEM-EDS, the cross-section of the rivet shows that the gilding layer was applied before the attachment of the rivets. It also shows that the gilding layer is distributed unevenly and there are empty spaces indicating amalgam gilding was employed. This was confirmed as Mercury was detected on the SEM-EDS analysis of the object. The examination of the microstructure of the plate using the SEM-EDS revealed that the object is made of a single copper alloy plate with recrystallized twining and non-metallic white inclusions, which found to be lead in this case.