• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.549-554
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• 2000

This study was carried out to estimate the contents of trace metals in the fishes and shellfishes available on Korean markets. The maples were digested with acids, then analyzed by ICP (INductively Coupled Plasma Spectrometer) and AAS (Atomic Absorption Spectrometer) for the contents of lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), manganese (Mn) and zinc (Zn). The contents of mercury (Hg) were determined using a mercury analyzer. The contents of trace metals [minimum~ maximum (mean), mg/kg] in fishes were as follows; Hg;0.004~0.500(0.082), Pb;N.D.~ 1.87 (0.29), Cd;N.D. ~0.094 (0.020), As;0.01~5045 (0.84), Cu;0.04~3.74 (0.66), Mn; N.D. ~7.56 (0.57), Zn;0.92~18.33(6.03). Those contents in shellfishes were as follows (mg/kg); Hg;N.D.~0.221 (0.029), Pb;0.01~1.51 (0.38), Cd;0.02~1.93 (0.51), As;0.18~3.07 study showed that trace metal contents in both fishes and shellfishes on our markets of lead, cadmium and mercury from fishes and shellfishes takes about 1~13% of PTWI(Provisional Tolerable Weekly Intakes) that FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.

• Journal of Applied Biological Chemistry
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• v.58 no.1
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• pp.65-74
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• 2015

X-ray absorption fine structure (XAFS) analysis using X-ray absorption spectroscopy is being applied as a state-of-the-art method in a wide range of disciplines. This review article summarizes the overall procedure of XAFS analysis from the preparation of soil samples to the analysis of data in X-ray absorption near edge structure (XANES) region and extended Xray absorption fine structure (EXAFS) region. The previous studies on application of XANES and EXAFS techniques in environmental soil science field are discussed and classified them according to metal(loid)s (As, Cd, Cu, Ni, Pb, and Zn). A significant number of previous studies of XAFS application in the environmental soil science field have focused on the identification of Pb chemical species in soil. Moreover, XANES and EXAFS techniques have been widely used to investigate the contamination source via identification of metal species. Similarly, these techniques were applied to identify the mechanisms of metal stabilization in soil after application of various amendments, phytoremediation, etc.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.205-210
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• 2005

The content of the trace metals in the cultured and wild fishes were determined. The tested fishes were genuin porgy (Pagrus major) and black porgy (Acanthopogrus schlegeli). The samples of the cultured and wild fishes were collected from slices of raw fish in shops, during 2003 to 2004. The samples were digested with acids, then analyzed by ICP (inductively Coupled plasma Spectrometer) and AAS (Automic Absorption Spectrometer) for the content of lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), manganese (Mn) and zinc (Zn). The content of mercury (Hg) was determined using mercury analyzer. The mean contents of trace metals in cultured and wild fish was 0.031,0.047mg/kg far total-mercury,0.321,0.407 for Pb, 0.048,0.063 for Cd, 1.006, 1.132 for As, 0.467,0.806 for Cu, 0.233, 0.293 for Cr, 9.69, 12.20 for Zn,0.798, 0.624 mg/kg far Mn, respectively. The content of all the trace metals except manganese in wild fish was more than that in cultured fish. The highest level of total-mercury, lead, cadmium, zinc, chromium and arsenic in the samples analyzed were all below the quarantine limit of Korean regulation and guideline established by the U.S. Food and Drug Administration f3r human consumption. The level of the trace metals in the samples was negligible, which could be endogenous. Our data obtained in this study showed that the average weekly intakes of lead, cadmium and mercury from cultured and wild fishes takes about $6\∼13\%$ of Un(Provisional Tolerance Weekley Intakes) that FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.535-544
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• 2013

Influence of sulfate on the early hydration in the solidification treatment of abandoned mine tailings was characterized. Solidified specimens using hydrated lime as a binder were prepared with various amounts of added $Na_2SO_4$ and different curing days. Unconfined compressive strength measurement, heavy metal leaching test, XRD analysis were performed after 7-, 14- and 28-days curing. According to curing days strength of solidified specimens using only distilled water increased but those with addition of $Na_2SO_4$ decreased. External cracks of specimens developed definitely with increasing $Na_2SO_4$ concentration and curing days. Concentrations of Cu, Cd, Zn, and As in the leached solutions from solidified specimens decreased significantly but Pb was leached readily in cases of hydrated lime dosage more than 10 wt%. Gypsum and $MgSO_4$ were identified in the cracked solidified specimens by XRD analysis, and pillar-shaped crystals of SEM image were identified as gypsum in reference with EDS analysis. Crystallization of sulfate in the process of lime-tailing solidification caused cracking, which should be supplemented for solidification treatment of highly sulfur-contained tailing.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.199-206
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• 2013

The Daehyun gold-silver deposit consists of two hydrothermal quartz veins that fill NE-trending fractures in the Cambro-Ordovician calcitic marble. I have sampled wallrock, hydrothermaly-altered rock and gold-silver ore vein to study the element dispersion and element gain/loss during wallrock alteration. The hydrothermal alteration doesn't remarkably recognized at this deposit and consists of mainly calcite, dolomite, quartz and minor epidote. The ore minerals composed of arsenopyrite, pyrrhotite, pyrite, sphalerite, stannite, chalcopyrite, galena, electrum, native bismuth and silver-bearing mineral. Based on analyzed data, the chemical composition of wallrock consists of mainly $SiO_2$, CaO, $CO_2$ with amounts of $Al_2O_3$, $Fe_2O_3(T)$ and MgO. The contents of $SiO_2$, $Fe_2O_3(T)$, MgO, CaO and $CO_2$ vary significantly with distance from ore vein. The element dispersion doesn't remarkably recognized during wallrock alteration and only occurs near the ore vein margin because of physical and chemical properties of wallrock. Remarkable gain elements during wallrock alteration are $Fe_2O_3(T)$, total S, Ag, As, Bi, Cd, Cu, Ni, Pb, Sb, Sn, W and Zn. Remarkable loss elements are $SiO_2$, MnO, MgO, CaO. $CO_2$ and Sr. Therefore, Our result may be used when geochemical exploration carry out at deposits hosted calcitic marble in the Hwanggangri metallogenic district.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2691-2696
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• 2009

Effects of representative group II and transition metal ions on the stability of the $poly(dA){\cdot}[poly(dT)]_2$ triplex were investigated by the van’t Hoff plot constructed from a thermal melting curve. The transition, $poly(dA){\cdot}[poly(dT)]_2\;{\rightarrow}\;poly(dA){\cdot}poly(dT)\;+\;poly(dT)$, was non-spontaneous with a positive Gibb’s free energy, endothermic (${\Delta}H^{\circ}$ > 0), and had a favorable entropy change (${\Delta}S^{\circ}$ > 0), as seen from the negative slope and positive y-intercept in the van’t Hoff plot. Therefore, the transition is driven by entropy change. The $Mg^{2+}$ ion was the most effective at stabilization of the triplex, with the effect decreasing in the order of $Mg^{2+}\;>\;Ca^{2+}\;>\;Sr^{2+}\;>\;Ba^{2+}$. A similar stabilization effect was found for the duplex to single strand transition: $poly(dA){\cdot}poly(dT)\;+\;poly(dT)\;→\;poly(dA)\;+\;2poly(dT)$, with a larger positive free energy. The transition metal ions, namely $Ni_{2+},\;Cu_{2+},\;and\;Zn_{2+}$, did not exhibit any effect on triplex stabilization, while showing little effect on duplex stabilization. The different effects on triplex stabilization between group II metal ions and the transition metal ions may be attributed to their difference in binding to DNA; transition metals are known to coordinate with DNA components, including phosphate groups, while group II metal ions conceivably bind DNA via electrostatic interactions. The $Cd_{2+}$ ion was an exception, effectively stabilizing the triplex and melting temperature of the third strand dissociation was higher than that observed in the presence of $Mg_{2+}$, even though it is in the same group with $Zn_{2+}$. The detailed behavior of the $Cd_{2+}$ ion is currently under investigation.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.146-154
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• 2015

Domestic railway industry has grown in numbers, scale of railway ndustrial and operation because was focused on an environmentally sustainable transportation. However, it is not enough to treat and prevent heavy metals which occur as the railway operation increases. The heavy metals occurred when the operating railway and it will be flow into water system with rainfall effluent during rainfall. will flow out along with the rainfall effluent when rainfall comes. In case of a railway bridge, In particular, heavy metals were flow into the water system without any treatment from railway bridges where located nearby rivers and lakes. So, rainfall effluent from railway facilities was occurred pollution of water system. For the prevent of heavy metal runoff during rainfall, the adsorptivity of material in railway roadbed is important.In this study, adsorptivity of gravel which is main gravel and blast-furnace slag were conducted adsorption test and deducted Freundlich's and Langmuir's isothermal adsorption equations. Safety as railway subbase course material was evaluated using modeling. As a result, absorption amount of slag, Cd and Cu, was shown higher than gravel and Pb along with Zn showed higher absorption amount of gravel. However, absorption amount of slag was shown higher than gravel used as railway subbase course material as time passes by. Absorption features had more suitable determination coefficient of heavy metals in warm absorption type such as Langnmuir compared to warm absorption type like Freundlich. To add, they showed less transformation by about 10% compared to gravel in safety evaluation through modeling. This is a railway subbase course material that prevents water outflow of heavy metal thus we can know slag is needed to be used.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1158-1167
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• 2000

To produce ${\beta}-cyclodextrin({\beta}-CD)$, a cyclodextrin glucanotransferase(CGTase) producing Aspergillus sp. CC-2-1 was isolated from soil. The enzyme was purified and its enzymological characteristics were investigated. It was found that production of CGTase reached to the maximum when the wheat bran medium containing 0.1% albumin, 2% $(NH_4)_2S_2O_8$, 2% soluble starch and 0.2% $KH_2PO_4$ was cultured for 5 days at $37^{\circ}C$. The purity of CGTase was increased by 13.14 folds after DEAE-cellulose ion exchange chromatography and Sephadex G-100, G-150 gel filtration and the specific activity was 172.14 unit/mg. Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. The molecular weight of CGTase was estimated to be 27,800 by Sephadex G-100 gel filtration and SDS-polyacrylamide gel electrophoresis. The optimum pH and temperature for the CGTase activity were 9.0 and $80^{\circ}C$, respectively. The enzyme was stable in pH $8.0{\sim}11.0$ at $60{\sim}80^{\circ}C$. The activity of purified enzyme was activated by $K^+,\;Cu^{2+}$ and $Zn^{2+}$. The activity of the CGTase was inhibited by the treatment with 2,4-dinitrophenol and iodine. The result suggests that the purified enzyme has phenolic hydroxyl group of tyrosine, histidine imidazole group and terminal amino group at active site. The reaction of this enzyme followed typical Michaelis-Menten kinetics with the $K_m$ value of 18.182 g/L with the $V_{max}$ of 188.68 ${\mu}mole/min$. The activation energy for the CGTase was calculated by Arrhenius equation was 1.548 kcal/mol.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.665-676
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• 2003

To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

• Clinical and Experimental Pediatrics
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• v.49 no.1
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• pp.18-23
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• 2006

Purpose : The reliability of hair mineral analyses regarding nutritional status, environmental exposure or diseases is controversial. The aim of this study was to determine the normal reference range of hair mineral concentration of Korean children. Methods : We examined hair mineral concentrations of 223 children(3-12 yrs old, 110 boys, 113 girls, mean age $8.8{\pm}2.2$ yrs old) living in the northern area of Seoul. The trace elements including six toxic elements(Al, As, Cd, Ba, Hg, Pb) and 11 nutritional elements(Na, Mg, P, K, Ca, Cr, Mn, Fe, Cu, Zn, Se) were analyzed by inductive coupled plasma mass spectrometry(ICP-MS). Results : The mean concentrations of Ca and Mg were higher in girls than in boys. The mean concentrations of Cd, Pb and Cr were higher in boys than girls. The Zn, Ca, Mg, Cu and Hg levels in hair samples were positively correlated with increasing age. The Zn levels of the Korean children's hair samples appear to be lower than that of other countries' reference values. Conclusion : There are considerable differences in hair mineral concentrations by age, sex and race. Additional research is needed to establish Korean reference values, and to evaluate the usefulness of hair mineral analyses as a screening tool for nutrition- and environment-related childhood diseases.