• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.21-27
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• 2012

This research was carried out as a survey on the contents of lead, cadmium, and arsenic in processed foods (milk, vegetable oil, and margarine) in Korea. The limits of quantification (LOQs) were Pb 0.3 ${\mu}g/kg$, Cd 0.15 ${\mu}g/kg$, and As 0.45 ${\mu}g/kg$ for milk and Pb 0.61 ${\mu}g/kg$, Cd 0.31 ${\mu}g/kg$, and As 0.91 ${\mu}g/kg$ for vegetable oil and margarine. The recoveries were 92.6-98.0% for Pb, 91.2-98.9% for Cd, and 97.9-104.7% for As. The average levels of Pb were 2.395 ${\mu}g/kg$ for milk, and 7.656 ${\mu}g/kg$ for vegetable oil. The average levels of Cd were 0.483 ${\mu}g/kg$ for milk, and 0.380 ${\mu}g/kg$ for vegetable oil, and levels of As were 0.781 ${\mu}g/kg$ for milk, and 1.241 ${\mu}g/kg$ for vegetable oil. The results of this study showed that Pb, Cd, and As contents in the whole samples were less than the maximum residual levels in the processed foods that were specified by the Codex standard.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.581-586
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• 2020

In this study, we investigated the illegal hazardous compounds in dietary supplements. We analyzed the contents of anti-obesity drugs, their analogues (orlistat, sibutramine, desmethylsibutramine, didesmethylsibutramine, chlorosibutramine, chlorosipentramine) and three heavy metals (lead (Pb), cadmium (Cd), arsenic (As)) in 62 other processed products (n=32), candies (n=7), weight control foods (n=10) and teas (n=13). Anti-obesity drugs or their analogues were not detected in any of the 62 samples. Three heavy metals (Pb, Cd, As) were detected in the range of ND-0.177 mg/kg, 0.002-0.233 mg/kg and 0.001-0.188 mg/kg in teas, ND-0.370 mg/kg, 0.003-0.057 mg/kg and 0.007-0.120 mg/kg in candies, ND-0.055 mg/kg, 0.012-0.045 mg/kg and 0.010-0.163 mg/kg in weight control foods, respectively. Heavy metals (Pb, Cd, As) were detected in the range of ND-2.324 mg/kg, 0.004-0.936 mg/kg and 0.003-21.247 mg/kg in other processed products that are not regulated by specification standards according to food types. These results show that regulations of heavy metals is required in other processed products for genuine food safety.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.230-234
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• 2011

According to the Codex committee, the maximum allowable level for lead in fruits is 0.1 mg/kg. This survey was conducted as a surveillance program following the establishment of safety guideline for fruits in Korea. Concentrations of lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) were measured in 927 samples using a ICP-MS and a mercury analyzer. The recoveries of microwave digestion method were 86.0-110.4% for Pb, 81.0-104.0% for Cd and 82.0-104.7% for As by standard addition method. The recovery of direct mercury analyzer was 106.5% for Hg. The average levels of Pb in ${\mu}g/kg$ were $10.0{\pm}12.8$ for apple, $8.8{\pm}10.9$ for pear, $4.1{\pm}4.4$ for persimmons, $14.9{\pm}12.3$ for mandarin, $7.1{\pm}6.5$ for orange, $3.1{\pm}3.3$ for banana, $8.8{\pm}8.9$ for kiwi, and $9.3{\pm}9.7$ for mango. The average levels of Cd in ${\mu}g/kg$ were $0.4{\pm}0.3$ for apple, $2.0{\pm}1.6$ for pear, $0.3{\pm}0.3$ for persimmon, $0.1{\pm}0.1$ for mandarin, $0.1{\pm}0.1$ for orange, $1.3{\pm}1.8$ for banana, $0.5{\pm}0.5$ for kiwi, and $0.7{\pm}0.6$ for mango. The average levels of As in ${\mu}g/kg$ were $2.0{\pm}2.1$ for apple, $1.2{\pm}1.3$ for pear, $1.5{\pm}1.2$ for persimmon, $0.8{\pm}0.3$ for mandarin, $1.5{\pm}0.5$ for orange, $1.8{\pm}1.2$ for banana, $1.6{\pm}1.5$ for kiwi, and $1.2{\pm}1.5$ for mango. The average levels of Hg in ${\mu}g/kg$ were $0.5{\pm}0.4$ for apple, $0.3{\pm}0.2$ for pear, $0.2{\pm}0.1$ for persimmon, $0.2{\pm}0.1$ for mandarin, $0.2{\pm}0.1$ for orange, $0.2{\pm}0.0$ for banana, $0.2{\pm}0.2$ for kiwi, and $0.6{\pm}0.2$ for mango. Based on the Korean public nutrition report 2005, these levels (or amounts) are calculated only at 0.17% for Pb, 0.013% for Cd and 0.006% for Hg of those presented in provisional tolerable weekly Intake (PTWI) which has been established by FAO/WHO. Therefore, the levels presented here are presumed to be adequately safe.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.264-270
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• 2021

In this study we investigated the elution level of lead (Pb), cadmium (Cd), arsenic (As), zinc (Zn), nickel (Ni), antimony (Sb), germanium (Ge), aluminum (Al) and hexavalent chromium (Cr⁶⁺) from 69 home-cooking utensils into a food stimulants. The results of migration testing according to the Korea standards and specifications for utensils, containers and packages showed values the allowable migrantion limits. Al was detected in all 7 utensil materials with the average concentration ranging from 0.002-5.989 mg/L. According to the migration conditions for (180℃, 30 min), the average concentration of Al in paper was 7.2 times higher than 25℃, 10 min (P<0.05). The results of migration testing at 180℃, 30 min were also below the allowable migrantion limits. When comparing with the provisional tolerable weekly intake (PTWI) of Al, the estimated weekly intakes (EWI) accounted for 0.000-0.045% for Al.

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.166-172
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• 2022

This study evaluated the migrant and residue tests of lead (Pb), cadmium (Cd), nickel (Ni), arsenic (As), and antimony (Sb) in 70 tumbler samples. The migration levels of hazardous metals in all the samples were within the migration limits outlined in the Korean standards and specifications for utensils, containers, and packages. Moreover, in all the tumbler samples, only Ni was detected in 0.5% citric acid solution of a food stimulant. The maximum level of Ni 0.0144 mg/L was 14.4% of the migrant specification (not more than 0.1 mg/L), which was relatively safe. The 0.5% citric acid solution was eluted at 4℃, 70℃, and 100℃ for 30 min, and only Ni was detected while testing for migration levels according to the temperature variations; all temperature conditions conformed to the standards. The level of Ni migration increased significantly with increasing migration temperature. Regarding the residue level outside the paint-coated tumbler samples, the Pb level was found to range from N.D. to 20638.1323 mg/kg. The risk of Ni was further estimated to be at a safe level of 0.00 to 0.01% compared to the %TDI as a result.

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.45-49
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• 2013

This study aimed to determine heavy metal contents in sesame oil samples produced in Korea through microwave-assisted acid digestion without using an emulsifier. Three heavy metal, cadmium (Cd), lead (Pb) and arsenic (As) in twelve sesame oil samples were determined by ICP-MS. The validation of analysis method was checked by standard addition method (10 and $100{\mu}g/kg$). As a result, linearity ($R^2$) was above 0.999 and RSDs were lower than 4%. The recovery of Cd, Pb and As ranged between 98.5-101.6%, 100.3-101.3%, and 102.1-111.2%, respectively. The detected ranges in sesame oil samples were as follows; N.D. to $0.109{\mu}g/g$ for Cd, 0.014 to $0.200{\mu}g/g$ for Pb and 0.014 to $0.125{\mu}g/g$ for As, respectively. Therefore, sesame seeds and products grown in heavy metal-polluted regions which are used as food should be given priority attention and consideration.

• Restorative Dentistry and Endodontics
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• v.39 no.2
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• pp.89-94
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• 2014

Objectives: The aim of this study was to evaluate the cytotoxicity, setting time and compressive strength of MTA and two novel tricalcium silicate-based endodontic materials, Bioaggregate (BA) and Biodentine (BD). Materials and Methods: Cytotoxicity was evaluated by using a 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide (XTT) assay. Measurements of 9 heavy metals (arsenic, cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc) were performed by inductively coupled plasma-mass spectrometry (ICP-MS) of leachates obtained by soaking the materials in distilled water. Setting time and compressive strength tests were performed following ISO requirements. Results: BA had comparable cell viability to MTA, whereas the cell viability of BD was significantly lower than that of MTA. The ICP-MS analysis revealed that BD released significantly higher amount of 5 heavy metals (arsenic, copper, iron, manganese, and zinc) than MTA and BA. The setting time of BD was significantly shorter than that of MTA and BA, and the compressive strength of BA was significantly lower than that of MTA and BD. Conclusions: BA and BD were biocompatible, and they did not show any cytotoxic effects on human periodontal ligament fibroblasts. BA showed comparable cytotoxicity to MTA but inferior physical properties. BD had somewhat higher cytotoxicity but superior physical properties than MTA.

• Journal of the Korean earth science society
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• v.37 no.4
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• pp.211-217
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• 2016

There have been found mine tailings, wastes, and mining drainage scattered in the area of Nakdong River due to the improper maintenance of the abandoned mines. These contaminants can flow into rivers during the heavy rain periods in summer. Along the study area beginning Seokpo-myeon, Bonghwa-gun of Gyeongsangbuk-do untill Dosan-myeon, Andong-si, there are one hundred five mines including sixty metalliferous mines and forty-five nonmetal mines, which can adversely affect the adjacent rivers. To verify the contamination, we collected sediments, seepage water and surface water for a year both in rainy season and dry season. This study found that sediments, containing high concentrations of heavy metals caused by mining activities, are dispersed throughout the entire river basin (68 sample points with pollution index, based on the concentration of trace element, (PI) >10 among the total of 101 samples). The results of river water analysis indicated the increased concentrations of arsenic and cadmium at branches from Seungbu, Sambo, Okbang and Janggun mine, which concerns that the river water may be contaminated by mining drainage and tailing sediments. However, it is difficult to sort out the exact sources of contamination in sediments and waters only by using the chemical compositions. Thus the control of mining pollution is challenging. To prevent water from being contaminated by mining activities, we should be able to divide inflow rates from each origin of the mines. Therefore, there should be a continued study about how to trace the source of contaminants from mining activities by analyzing stable isotopes.

• Journal of the Korean GEO-environmental Society
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• v.7 no.1
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• pp.41-53
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• 2006

In this study, estimation of nonlinear adsorption isotherms(Langmuir & Freundlich adsorption isotherm) and advection-dispersion model parameters was conducted using genetic algorithm(GA) for Zn and Cd adsorption. Estimated parameters of nonlinear adsorption isotherms, which were obtained from the optimization process using genetic algorithm(GA), are nearly same with the parameters obtained from a linearization process of the nonlinear isotherms. Estimated effective diffusion coefficients, which were obtained from a finite element analysis of the advection-dispersion model and an optimization procedure using the genetic algorithm, for the metals were approximately in the order of $10^{-7}cm^2/s$ which could be obtained based on the linear distribution coefficient. The effective diffusion coefficients based on the nonlinear retardation factors were in the range of $10^{-6}{\sim}10^{-5}cm^2/s$. As a result, the correlation coefficient obtained between the measured and calculated concentration was over 0.9 which means that the genetic algorithm should be successfully applied to estimate the unknown parameters of the nonlinear adsorption isotherms and advection-dispersion model.

• Economic and Environmental Geology
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• v.38 no.2 s.171
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• pp.135-142
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• 2005

In order to investigate the contamination level and seasonal variation of heavy metals and evaluate the bioavailability of toxic elements, environmental geochemical survey was undertaken at the Dogok Au-Ag-Cu mine area. The main pollution sources in the area were suggested as tailings, mine waste materials and mine water. Elevated levels of $140{\cal}mg/{\cal}kg{\;}As,{\;}107{\cal}mg/{\cal}kg{\;}Cd,{\;} 3017{\cal}mg/{\cal}kg{\;}Cu,{\;}12926{\cal}mg/{\cal}kg{\;}Pb,{\;}9094{\cal}mg/{\cal}kg$ Zn(before rainy season) were found in mine tailings. Concentrations of heavy metals in farmland soils exceeded normal level in nature soil (Bowen, 1979). The highest level of heavy metals was found in water samples near the mine tailing dumps regarded as a main pollution source of toxic elements in the area. These concentrations decreased to downstream due to the effect of dilution. From the results of sequential extraction analyses for tailings and soils, non-residual forms of heavy metals were found, which indicate the contamination to be progressing by continuing weathering and oxidation. Cadmium and Zn would be of the highest mobility in all samples. The bioavailability of Cd, Cu, Zn and As using SBET analysis from paddy soils was $53.3{\%},{\;}46.5{\%},{\;}41.0{\%}$ and $37.0\%$, respectively. The farmland soil sample(S3) showed the highest total concentration and bioavailability of heavy metals.