• Analytical Science and Technology
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• v.32 no.6
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• pp.233-242
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• 2019

Substance identification is the first step of the REACH registration. It is essential in terms of Classification, Labelling and Packaging (CLP) regulation and because even trace amounts of impurities or additives can affect the classification. In this study, a scheme for the screening, quantification, and interpretation of trace amounts of hazardous inorganic substances is proposed to detect the presence of more than 0.1% hazardous inorganic substances that have been affecting the hazard classification. An exemplary list of hazardous inorganic substances was created from the substances of very high concern (SVHCs) in REACH. Among 201 SVHCs, there were 67 inorganic SVHCs containing at least one or ~2-3 heavy metals, such as As, Cd, Co, Cr, Pb, Sb, and Sn, in their molecular formula. The inorganic SVHCs are listed in excel format with a search function for these heavy metals so that the hazardous inorganic substances, including each heavy metal and the calculated ratio of its atomic weight to molecular weight of the hazardous inorganic substance containing it, can be searched. The case study was conducted to confirm the validity of the established scheme with zinc oxide (ZnO). In a substance that is made of ZnO, Pb was screened by XRF analysis and measured to be 0.04% (w/w) by ICP-OES analysis. After referring to the list, the presence of Pb was interpreted just as an impurity, but not as an impurity relevant for the classification. Future studies are needed to expand on this exemplary list of hazardous inorganic substances using proper regulatory data sources.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.163-168
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• 2006

In order to develop the deep ocean water, we performed to study the characteristics of vertical distribution of dissolved trace metals(Cd, Co, Cu, Ni, Pb, Zn) from Apr. to Oct., 2005 in the East Sea. Total six sampling sites were selected in Gangwon-Do and Gyeongsanbuk-Do. Accuracy of the analytical procedures was assessed by the SRM(CASS-4) for dissolved metals in seawater. The mean recoveries of CASS-4 ranged from 89.4% for Co to 99.8% for Cd. In this study, the dissolved metal concentrations varied with space, time and element. The metal concentrations showed wide range in the surface. Cd, Ni and Zn showed a nutrient-type profile with surface depletion and enrichment at depth. However, Co, Cu and Pb were irregular in the vertical distribution. All metal concentrations studied in this study are lower than the criteria of Korean drinking water.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.112-127
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• 1997

The purpose of this study is to get optimum operating factors of Upflow Anaerobic Sludge Blanket (UASB) reactor by introducing methods that make it to reduce inhibition possible in each process wastewater treatment. The used substrates, concentrated corn starch liquid (CSL) wastewater, modified starch, filtering and decoloring wastewater, ion refining wastewater, and mixed wastewater including modified starch and not including modified starch, are generated from molasses process. The seeding sludge is the digested sludge that had been applied to molasses wastewater. Batch test to reduce the inhibition factors that might be existed in each wastewater was examined. Based on the this test, the optimum operating factors according to alkalinity and pH variation was studied through the continuous test using three 5.5 L UASB reactor. The first reactor added $NaHCO_3$ to control alkalinity. The hydraulic retention time (HRT) reduced to 8 hours and the organic loading rate increased gradually. The second reactor changed the pH of influent from 7.0 to 6.0 using NaOH. The third reactor was operated without changes to compare the above two reactors. As the result, the inhibition in concentrated CSL wastewater was removed by adding iron (II). When trace metals were added to mixed wastewater not including modified starch, the digestability by gas production rate increased to more fifty percentage than mixed wastewater that was not adding the trace metals. The reason that the inhibition did not decreased in spite of adding trace metals and nutrients was influenced by high concentration generated during the acid fermentation. The UASB reactors using the mixed wastewater with the most effective performance were operated as 500 mg/L as $CaCO_3$ alkalinity and 6.0 pH at steady state, and at this time, the gas production rates were 283 and 311mL gas/g $COD_{added}$. The COD removal rates were 84.7 and 86.3%, respectively.

• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.603-610
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• 2008

A mathematical model was developed to understand how the presence of plants affects vertical profiles of electron acceptors, their reduced species, and trace metals in the wetland sediments. The model accounted for biodegradation of organic matter utilizing sequential electron acceptors and subsequent chemical reactions using stoichiometric relationship. These biogeochemical reactions were affected by the combined effects of oxygen release and evapotranspiration driven by wetland plants. The measured data showed that $SO_4{^{2-}}$ concentrations increased at the beginning of the growing season and then gradually decreased. Based on the measured data, it was hypothesized that the limitation of the solid phase sulfide in direct contact with the roots may result in the gradual decrease of $SO_4{^{2-}}$ concentrations. With the dynamic formulation for the limitation of the solid phase sulfide, model simulated time variable sulfate profiles using published model parameters. Oxygen release from roots produced divalent metal species (i.e. $Cd^{2+}$) as well as oxidized sulfur species (i.e. $SO_4{^{2-}}$) in the sediment pore water. Evapotranspiration-induced advection increased flux of divalent metal species from the overlying water column into the rhizosphere. The increased divalent metal species were converted to the metal sulfide with sufficient FeS around the rhizosphere, which contributed to the decrease of bioavailability and toxicity of divalent metal activity in the pore water. Since the divalent metal activity is a good predictor of the metal bioavailability, this model with a proper simulation of solid phase sulfide plays an essential role to predict the dynamics of trace metals in the wetland sediments.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.209-218
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• 2000

This study was conducted to determine the content of trace metals in crops cultivated in Han-riverside, Anyang stream, Tan stream, and Jungryang stream. Trace metals (Pb, Cr, Cd, Fe, Zn, Cu, Hg) were detected in 36 crops, 285 samples by Atomic Absorption Spectrophotometer and Mercury Analyzer. The average concentration of trace metals in crop samples was in the order of Fe (34.592 ppm)>Mn (11.071 ppm)$\geq$Zn(8.853 ppm)>Cu(1.795 ppm)>Cr(0.237 ppm)>Pb(0.100 ppm)>Cd(0.011 ppm)>Hg(0.003 ppm). In crop samples, the contents of Fe, Cu, Mn, and Zn, which ranges were 0.004-203.083 ppm, 0.017~22.727 ppm, 0.000~74.373 ppm, 0.080~37.166 ppm, respectively, were relatively higher than those of Pb, Cd, Cr, and Hg, which ranges were 0.000~0.654 ppm, 0.000~0.270 ppm, 0.000~l.229 ppm, 0.000~0.037 ppm, respectively. The concentration of trace metals in crop samples was in the order of leafy vegetables > stem vegetables > root vegetables > fruity vegetables. In the root vegetables, such as radish, the content of Pb was leaf(0.055 ppm)>root(0.035 ppm), that of Cr, leaf (0.118 ppm)>root(0.031 ppm), that of Cd, leaf(0.004 ppm)>root(0.001 ppm), that of Hg, leaf(0.004 ppm)>root(0.001 ppm). As the results, it could be thought that root is the organ which doesn't accumulate the heavy metal ions, but absorb them.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.223-230
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• 2003

This study was conducted to estimate the contents of 6 trace metals in potatoes and root vegetables purchased in wholesale market in the Seoul region, specifically, Cu. As, Zn, Pb, Cd and Hg. The minimum and maximum results obtained for each metal are summarized as follows for potatoes; Cu : 0.094∼0.344, As : N.D∼0.070, Zn : 0.247∼1.547, Pb : N.D∼0.268, Cd : N.D∼0.005, Hg : 0.001∼0.027, and for root vegetables; Cu : 0.021∼0.510, As : 0.004∼0.045, Zn : 0.143∼3.137, Pb : N.D∼0.372, Cd : N.D∼0.009, Hg : 0.001∼0.195. The daily intakes of trace metals from potatoes and root vegetables were estimated on the basis of the daily intake of these foods by Koreans, which were 0.073∼22.253 and 0.567∼156.219$\mu\textrm{g}$ from potatoes and root vegetables, respectively. The weekly intakes of trace metals were 0.009∼2.596 and 0.066∼18.224$\mu\textrm{g}$ for potatoes and root vegetables, respectively. The weekly intakes of trace metals for potatoes and root vegetables were very much lower than the PTWI(provisional tolerable weekly intake), enough to be within a safe range.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.155-163
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• 2014

Total concentration and chemical speciation of trace metals (Cu, Pb, Zn, Cd, and Ni) were determined to evaluate pollution level and potential ecological risk in surface sediments of the Masan Bay. The results showed that the trace metal concentrations, except for Ni, were high in the inner Masan Bay. Based on the chemical speciation of metals in sediments, the percentage of total concentrations of Cd and Pb in non-residual fraction was 92% and 88%, respectively, indicating that these metals originated mainly from anthropogenic sources. However, Ni (70%) was dominant in residual fraction. Pollution load index (PLI) and ecological risk index (ERI) values in the inner bay indicate the presence of anthropogenic pollution and considerable-moderate ecological risk, respectively. Ecological index (Ei) value for Cd was high at most stations in the Masan Bay, and Cd content was the highest in acid soluble fraction, which presents the highest ecological risk. The results obtained in this study indicate that Cd presents a high potential ecological risk to benthic biota in the Masan Bay.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.169-179
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• 2011

To investigate the controlling factor and accumulation of trace metal concentrations in Chun-su Bay sediments, grain-size, specific surface area, organic carbon content, calcium carbonate content, and concentration of Al, Fe, Na, K, Mg, Ca, Ti, Mn, P, S, Ba, Sr, Li, Co, Cr, Ni, Cu, Zn, As, Cd, Cs, Sc, V, Sn were analyzed. Controlling factors of metals were quartz-dilution, calcium carbonate and coarse sand or K-feldspar. Although the distribution of V, Co, Cr, Ni, Cu, Zn, Sn, and Cd concentration was explained by grain-size effiect, Mn and As showed the similar importance of grain-size effect and coarse sand or K-feldspar factors. By virtue of enrichment factor and 1 M HCl experiment, there were little enrichment in all the trace metals in bay sediments, which were explained well by geochemical properties of sediments. Since the concentration levels of As in coarse sand were high as much as those in fine-grained sediments and it was combined with Mn oxide (1 M HCl leached) and K-feldspar (residual), it was suggested that when the enrichment of As in sediments would be assessed, it is necessary to separate the coarse sand from bulk sediments or to use only sediments with higher than 10% in < $16{\mu}m$ fraction.

• Korean Journal of Veterinary Service
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• v.22 no.1
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• pp.1-7
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• 1999

This study was performed to investigate the contents of the heavy metals such as cadmium(Cd), copper(Cu), iron(Fe), lead(Pb) and zinc(Zn) in meat and meat products. For this experiment, each 20 samples of beef and pork were collected at slaughterhouse in Seoul areas and 45 samples of meat products(ham, sausage, processed meat and seasoned meat) were purchased from commercial food markets. The contents of the heavy metals was determined by atomic absorption spectrophotometry from Jan. to Nov. In 1998. The results obtained were summarized as follows ; 1. In Korean native beef, mean values of the heavy metals(mg/kg) were Pb : 0.14$\pm$0.10, Cd : 0.07$\pm$0.02, Cu : 1.73$\pm$0.95, Zn : 42.82$\pm$8.17 and Fe : 67.43$\pm$24.18, respectively. 2. In imported beef, mean values of the heavy metals(mg/kg) were Pb : 0.03$\pm$0.08, Cd : 0.06$\pm$0.02, Cu : 1.41$\pm$0.62, Zn : 42.93$\pm$4.95 and Fe : 40.06$\pm$12.77, respectively. 3. In pork, mean values of the heavy metals(mg/kg) were Pb : not detected, Cd : 0.09$\pm$0.02, Cu : 1.08$\pm$0.23, Zn : 19.49$\pm$6.02 and Fe : 30.21$\pm$10.51, respectively. 4. In ham, mean values of the heavy metals(mg/kg) were Pb : trace, Cd : trace, Cu . 1.19$\pm$0.46, Zn : 13.58$\pm$4.99 and Fe : 31.43$\pm$11.74, respectively. 5. In sausage, mean values of the heavy metals(mg/kg) were Pb : 0.15$\pm$0.34, Cd : 0.08$\pm$0.05, Cu : 1.15$\pm$0.46, Zn : 13.70$\pm$7.13 and Fe . 27.28$\pm$15.05, respectively. 6. In processed meat, mean values of the heavy metals(mg/kg) were Pb : 0.08$\pm$0.13, Cd : 0.09$\pm$0.04, Cu : 1.28$\pm$0.60, Zn : 14.72$\pm$7.09 and Fe : 24.04$\pm$10.33, respectively. 7 In seasoned meat, mean values of the heavy metals(mg/kg) were Pb : 1.05$\pm$2.21, Cd : 0.13$\pm$0.03, Cu : 1.06$\pm$0.16, Zn : 17.53$\pm$8.72 and Fe : 26.76$\pm$9.02, respectively.

• 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.