• Carbon letters
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• v.15 no.4
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• pp.238-246
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• 2014

People have been concerned about mercury emissions for decades because of the extreme toxicity, persistence, and bioaccumulation of methyl Hg transformed from emitted Hg. This paper presents an overview of research related to mercury control technology and identifies areas requiring additional research and development. It critically reviews measured mercury emissions progress in the development of promising control technologies. This review provides useful information to scientists and engineers in this field.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3459-3464
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• 2014

Synthesis and structural characterization of mercury(II) halides and perchlorate complexes (1-4) of bis-$OS_2$-macrocycle (L) are reported. L reacts with mercury(II) chloride and bromide to yield an isostructural 2D coordination polymers with type $[Hg(L)X_2]_n$ (1: X = Cl and 2: X = Br). In 1, each Hg atom which lies outside the cavity is six-coordinate with a distorted octahedral geometry, being bound to four adjacent ligands via monodentate Hg-S bonds and two remaining sites are occupied by two terminal chlorido ligands to form a fishnet-like 2D structure. When reacting with mercury(II) iodide, L afforded a 1D coordination polymer $\{[Hg_2(L)I_4]{\cdot}CHCl_3\}_n$ (3) in which each exocyclic Hg atom is four-coordinate, being bound to two sulfur donors from different ligands doubly bridging the ligand molecules in a head-to-tail mode. The coordination sphere in 3 is completed by two iodo terminal ligands, adopting a distorted tetrahedral geometry. On reacting with mercury(II) perchlorate, L forms solvent-coordinated 1D coordination polymer $\{[Hg_2(L)(DMF)_6](ClO_4)_4{\cdot}2DMF\}_n$ (4) instead of the anion-coordination. In 4, the Hg atom is five-coordinate, being bound to two sulfur donors from two different ligands doubly bridging the ligand molecules in a side-by-side mode to form a ribbon-like 1D structure. The three remaining coordination sites in 4 are completed by three DMF molecules in a monodentate manner. Consequently, the different structures and connectivity patterns for the observed exocyclic coordination polymers depending on the anions used are influenced not only by the coordination ability of the anions but also by anion sizes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.675-683
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• 2017

Total mercury (T-Hg) and methyl mercury (MeHg) were determined in marine fisheries (41 species, n=87) commonly consumed in Korea, using a gold amalgamation method and gas chromatography-cold vapor atomic fluorescent spectroscopy, respectively. Concentrations of T-Hg and MeHg in all samples (31 fish, 4 crustaceans, 4 cephalopods, and 2 gastropod species) were in the range of 0.016-0.495 (mean, 0.093) mg/kg-wet and not detected-0.338 (mean, 0.067) mg/kg-wet, respectively. The concentrations of MeHg in marine fisheries were significantly correlated with T-Hg concentrations (P<0.001). The highest mean concentrations of T-Hg and MeHg were found in fish species, followed by crustaceans. The contribution of MeHg to T-Hg was in the range of 64-95% (mean, 83%) in cephalopods, 28-98% (mean, 69%) in fish, and 26-88% (mean, 57%) in crustaceans. The weekly intakes of T-Hg and MeHg by fisheries consumption for the Korean general population were estimated to be 0.463 and $0.338{\mu}g/kg$ body weight/week, respectively. The concentrations and intakes of T-Hg and MeHg were less than the allowable residue levels and in the range of 12 to 17% of the provisional tolerable weekly intake (PTWI) applied in Korea.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.4-15
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• 2005

Methylmercury (MeHg) is an environmental pollutant with neurotoxic effects on the central nervous system. The major exposure route of MeHg to humans is via consumption of fish and shellfish which accumulate the chemical through the food web in an aquatic environment. Hair mercury level is an excellent marker for MeHg exposure. We have been conducting a survey on hair mercury contents among general populations from 14 districts to estimate the current Japanese MeHg exposure level. Total mercury levels of all hair samples collected (12923 in total) were analyzed by the oxygen combustion-gold amalgamation method using an atomic absorption mercury detector. Multiple regression analysis revealed that mercury levels were significantly correlated with several covariates, such as sex, age, the amount of daily intake of total fish/shellfish, a preference for certain fish such as tuna or bonito, and artificial waving. The geometric means for the population without artificial waving were 2.47 and 1.65 ${\mu}g/g$ for males (n = 5623) and females (n = 3470), respectively. Hair mercury levels varied with age, and the variations were more significant in males. Since the difference between sexes was not evident at younger ages, some hormonal control might also be involved in the mercury uptake by human hair. The average mercury levels in our hair samples varied among the sampling districts. Tuna is a major carnivorous fish with high mercury accumulations that is often consumed in Japan. The amount of fish consumption and the preference rate far tuna would appear to be responsible far the regional variation in hair mercury levels in Japan. Recently, a provisional tolerable weekly intake (PTWI) of MeHg was revised by 61st JECFA to 1.6 ${\mu}g/kg/week$, which was about half that of the Japanese standard, and corresponded to a hair level of 2.2 ppm. The distribution of hair mercury levels in Japanese populations in the present study indicated that 25% of the Japanese females of child-bearing age were estimated to be exposed to MeHg over the PTWI level. This would reflect the high Japanese consumption of marine products. However, not only mercury contamination, but also the nutritional benefit may have to be considered when discussing the risk involved in the current level of fish and shellfish consumption in Japan.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.5
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• pp.593-596
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• 1996

The encironmental consequences of airborne mercury (Hg) release from waste incineration system are wellperceived. To provide some insights into those phenomena, we have assessed annual emission rates of Hg for several major incineration systems in Korea following the procedures developed abroad. The results of our computation, derived on the basis of dividing the whole amounts of annually incinerated wastes into municipal solid Wastes (MSW), and medical solid wastes (MDW), indicate that the extent of Hg release may be significant nationwide, possibly approaching a few tonnes of Hg per year basis. Knowing that the airborne transport and the resulting deposition of Hg can exert serious pollutions to the aquatic ecosystems, of particular fisheries, we are obliged to establish a stringent measure to confine the amount of Hg released via incineration.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.289-294
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• 1997

The cycles of heavy metals, mercury, lead and cadmium, were investigated on in dynamic grassland ecosystems at a steady state in Zoysia japonica and Miscanthus sinensis in Mt. Kwanak, Korea. Estimates of decay constants of heavy metals based on experimental and methomatical model, were Hg 0.14, Pb 0.17 and Cd 0.41 of Z. japonica grassland, and Hg 0.33, Pb 0.13 and Cd 0.56 of M sinensis grassland. The durations of reaching half of initial amounts in Z. japonica and M. sinensis grassland, were Hg 4.95, Pb 4.07 and Cd 1.69 years, and Hg 2.10, Pb 5.33 and Cd 1.24 years respectively. Times needed for 99% decomposed were longer in Z. japonica than M. sinensis grassland. Decay velocity of constituents of surface soil layers were more rapidly in M. sinensis than Z. japonica grassland. Key words: Cycles of heavy metals, Mercury, Lead, Cadmium, Zoysia japonica. Miscanthus sineusis, Mt. Kwanak, Decay constants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.2
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• pp.144-147
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• 1986

This research is to investigate the changes in Mercury content of fishes, washed with times by the flowing water or immersed into the acetic acid solutions with different densities (1%, 3% and 5%), after contaminating them artificially on purpose, in the solutions with inorganic mercury. The results were summarized as follow: 1. Average values of mercury content in sand-fish and sardine, as a dried ones, which had not been treated by the mercurial solutions, were 0.027 ppm and 0.020 ppm, respectively. 2. According to the changes, with times, in contained by the flowing water, after immersed into 1 ppm $HgCl_2$ solution for 24 hours, The sand-fish washed for 9 minutes had the least of Mercury, which is about 25% of contained quantity of Mercury of those not cleansed. While the sardines cleansed for 3 minutes had the least of Mercury, which is about 77% of contained quantity of Mercury of those not cleansed. 3. According to the changes in contained quantity of the samples treated by the acetic acid solutions with different densities, the sand-fish treated by 3% acetic acid solution had the least value of remains, which was reduced by 64%, in comparision with that of fish cleansed for 1 minute, while the sardines, treated by 1% acetic acid solution had the least amount of remains, which was reduced by 16% in comparision with that of fish, cleansed for 1 minute.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.559-564
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• 2004

The effects of intra-peritoneal injection of inorganic mercury on haemato-logical parameters and hepatic oxidative stress enzyme activities were studied in common carp, Cyprinus carpio. The fish were injected thrice intra-peritoneally with mercuric chloride TEX>$(5,\;10mg\;Hg\;kg\;b.W.^{-1})$. After exposure of three different mercury concentrations a physiological stress response was exerted on C. carpio by causing changes in the blood status such as erythropenia in blood and oxidative stress in liver. Red blood cell counts, hemoglobin concentration and hematocrit level were reduced in most cases by inorganic mercury. Remarkable low level of serum chloride, calcium and osmolality were also observed in the mercury- exposed fish. However, serum magnesium and phosphate were not altered by exposure to mercury. An increased activity of hepatic glutathione peroxidase was observed in the lowest treatment group of carp $(1mg\;Hg\;mg\;b.w.^{-1})$, hence, hepatic catalase and glutathione peroxidase of carp exposed to higher concentration of mercury $(5,\;10mg\;Hg\;kg\;b.W.^{-1})$ showed significant reduction in such activities.

• YAKHAK HOEJI
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• v.26 no.4
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• pp.253-256
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• 1982

The organ distribution of mercury was examined in the rat after oral administration of a single dose of red mercuric sulfide (15mg Hg/kg). The concentration of total mercury in the organs and blood after 2, 4, 6, 8, 12, 24 and 72 hours of administration was determined by Quartz Tube Combustion-Gold Amalgamation Method. It was found that the maximal concentration of total mercury was in the kidneys and muscle within 24 hours and in the brain, heart, liver and blood within 48 hours. The descending order of the maximal organ and blood concentration was: kidneys(1.08ppm)>blood> muscle>heart>liver>brain. The accumulation states of total mercury in the rat organs were investigated by continuous administration of red mercuric sulfide (5mg Hg/kg/day) for 15 days. The mercury concentration increased progressively throughout the experimental period and the descending order of the highest level of mercury after 15 days was: kidneys (1.55ppm)>blood>liver. The concentration of alkyl mercury in brain, liver and kidneys also was measured after 7 and 15 days of consecutive administration of red mercuric sulfide (5mg Hg/kg/day). The concentration in the Kidneys and the liver was very low, but was significantly different from control group. The concentration in the brain was extremely low and was not significantly different from control group.

• Journal of the Korean earth science society
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• v.24 no.1
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• pp.1-6
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• 2003

In this work, the present concentration levels of total gaseous mercury (TGM) are compared among three East Asian countries, Korea, China, and Japan. Comparison of Hg distribution patterns was made by selecting representative figures for each type of land use among those three countries. The results of the analysis indicate that Hg concentrations within a country can fall into a wide range due probably to the diversity of source processes. It is seen that the urban areas of China and Japan generally exhibit large spatial variability with notably high Hg levels (above 10 ng m$^{-3}$), compared to their Korean counterparts. Although the presence of high Hg levels in Chinese locations can be accounted for by the major man-made source processes (e.g., the use of coal), the causes of unexpectedly high Hg data in Japanese sites appear to be rather complicated. The Hg concentration levels in relatively remote locations however show much reduced values, above 3 ng m$^{-3}$, which is still higher than the typical background concentrations of 1 to 2 ng m$^{-3}$ in Europe or America. Considering that the presence of unusually high Hg levels in urban areas of Asia is the consequence of man-made activities, the prevalence of excessively high Hg values in certain regions of the Asian continent needs further research to accurately assess the fundamental picture of Hg geochemistry in the East Asia.