• 한국지하수토양환경학회지:지하수토양환경
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• 제27권3호
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• pp.11-21
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• 2022

The purpose of this study was to evaluate the influences of digestion temperature on the extraction of heavy metals from soil using the standard method established by Korean Ministry of Environment (KMES). A total of 7 heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn) in soil samples were extracted at varying digestion temperatures [(66 ± 2.0)℃, (73 ± 1.9)℃, (80 ± 1.3)℃, (85 ± 1.7)℃, (92 ± 2.0)℃, (98 ± 1.7)℃]. As, Cd, Cu, Pb and Zn concentrations remained relatively constant over the temperature range, but Ni and Cr concentrations greatly varied with the digestion temperature. The extent of variation in extraction efficiencies as compared to the concentration obtained at 66℃ was in following order; Ni (7.09% ~ 35.42%) > Cr (4.79% ~ 25.40%) > Zn (3.99% ~ 17.52%) > Cu (2.22% ~ 19.34%) > As (3.54% ~ 8.26%) > Cd (-5.08% ~ 1.08%) > Pb (-4.71% ~ -1.70%). The accuracy for certified reference materials at the digestion temperature of 80 and 85℃ was 98.7% ~ 105.8%. Therefore, digestion temperature of 80℃ ~ 85℃ is suggested to obtain reliable and reproducible data when the standard method by Korean Ministry of Environment is employed to analyze multiple heavy metal components in soil samples.

• 한국환경보건학회지
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• 제50권1호
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• pp.25-35
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• 2024

Background: There are concerns about the health effects of various environmental pollution exposures among residents living near coal-fired power plants (CFPP). Objectives: This study attempted to compare the concentrations of heavy metals in blood and urine and those of urinary volatile organic compound (VOC) metabolites according to the residential separation distance. Methods: Participants in the study totaled 334 people who have lived for more than 10 years in areas within 10 km of a CFPP. The separation distance was analyzed in quartiles by dividing it into Q1 (88 people), Q2 (89 people), Q3 (89 people), and Q4 (68 people). We explained the purpose of this study to the participants and collected blood and urine after obtaining signatures on a participation agreement. Results: The study participants were 102 males (30.5%) and 232 females (69.5%), with an average age of 71. The average length of residence and distance were 43.8 years and 4,800 meters. The geometric mean concentrations of Pb, Cd, and Hg in blood and As and Cd in urine were respective 1.35 ㎍/dL, 1.43 ㎍/L, 3.16 ㎍/L. They were 167.88 ㎍/g for creatinine and 1.58 ㎍/g creatinine. The metabolite concentrations of VOCs were 50.67 ㎍/g creatinine in t, t-muconic acid (t, t-MA), 10.73 ㎍/g creatinine in benzyl mercapturic acid, 317.05 ㎍/g creatinine in phenylglyoxylic acid, 123.55 ㎍/g creatinine in methylhippuric acid, and 190.82 ㎍/g creatinine in mandelic acid. The concentration of Pb in the blood and Cd and t, t-MA in the urine of residents within affected area of the CFPP showed statistically significant differences among distance groups. Conclusions: The concentration of urinary VOCs metabolites, especially t, t-MA, differed according to the distance groups of residents within the affected area of CFPP (p<0.05).

• Tuberculosis and Respiratory Diseases
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• 제52권1호
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• pp.37-45
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• 2002

연구배경 : 미만성 범세기관지염은 임상적으로 기침, 객담 및 노작성 호흡곤란을 특징으로 하며 기관지확장증으로 진행하는 만성 염증성 폐질환이다. 기관지확장증의 발생 기전은 정액 과다분비 및 배상세포의 이형성과 동반된 염증성 매개물질에 의해 조절되며 이 과정에서 epidermal growth factor receptor (EGFR)가 관여하는 것으로 알려져 있다. 미만성 범세기관지염 환자에서의 배상세포의 이형성과 EGFR의 발현, 호중구에 의한 염증성 매개물질 사이의 연관을 살펴보았다. 방 법 : 13명의 미만성 범세기관지염 환자군과 6명의 정상 대조군을 대상으로 점액 과다분비에 대한 EGFR의 역할을 보기 위해 alcian blue/periodic acid(AB/PAS) 염색과 MUC5AC, EGFR, CD16 면역 조직 화학 염색을 시행하였다. 결 과 : 미만성 범세기관지염 환자군의 AB/PAS 염색과 MUC5AC 염색 정도는 $8.31{\pm}3.36%$, $11.46{\pm}4.68%$ 이었고, 정상 대조군의 AB/PAS 염색과 MUC5AC 염색은 $50.5{\pm}5/77%$, $53.3%{\pm}6.67%$로 정상 대조군에서 환자군에 비해 유의하게 높았다(p<0.05). EGFR의 발현은 환자군에서는 $9.54{\pm}4.95%$이었으나 정상 대조군에서는 전혀 나타나지 않았다. 호중구 침윤은 환자군에서 $71.92{\pm}3.71$HPF 이었고, 정상 대조군에서는 $45.0{\pm}5.73$/HPF로 환자군에서 정상 대조군에 비해 유의하게 높았다(p=0.002). 결 론 : 미만성 범세기관지염에서 EGFR의 발현이 점액 과다 분비와 배상세포의 이형성 및 호중구성 염증과 연관을 보이는 것으로 사료된다.

• 한국환경보건학회지
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• 제33권6호
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• pp.502-505
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• 2007

To estimate the soil quality of Miryang area, soil analysis were conducted according to the city and out of city of soil expenses at according to analysis components and heavy metal pollution of irradiation sampling sites. The through soil components the principal element about the 71% $SiO_2\;and\;Al_2O_3$, the pH of field area near the city center was lower than that of the other field area, which indicated that this acidification was probably attributed to the acid rain caused by the traffic exhaust gas such as $SO_x\;and\;NO_x$. Acidification was more severe in the field area than in the farming land. The concentration of five heavy metals such as Cu, Cd, Pb, As and Cr were found to be lower than the standard of soil pollution. An assessment using the SPI(Soil Pollution Index), which was developed to estimate an overall soil quality, was performed. Each SPS(Soil Pollution Score) were evaluated with the results of the data from this study. The soil quality of most area of Miryang land was determined to Class 1, which indicated that the soil was healthy.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.45-50
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• 2000

We have investigated the influence of columnar defects (CD) on the vortex dynamics in pristine and iodine-intercalated Bi$_2$Sr$_2$CaCu$_2$O$_{8+{\delta}} single crystals from do SQUID magnetization measurements. Especially, the temperature dependence of the irreversibility fields, H$_{irr}$(T), were studied. Anisotropy ratio ${\gamma}$, estimated from the fitting to the 2-dimensional melting model (A. Schilling et al., Phys. Rev. Lett. 71 1899 (1993)) in higher fields than the matching field B$_{\phi}$ at low temperature region, turns out to be decreased by the iodine-intercalation and additionally by the heavy-ion irradiation.

• 한국환경농학회지
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• 제31권2호
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• pp.97-103
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• 2012

BACKGROUND: Metal mines were actively developed in the early twentieth century in Korea; however, most of these mines were closed and abandoned without proper management. Therefore, toxic metal contamination in the vicinity of Korean abandoned metal mines has been reported. A risk assessment for these metals was performed for residents near by abandoned Sanyang metal mine. METHODS AND RESULTS: Soil and groundwater samples were collected from May to October 2007 around the mine. After pretreatment of these samples, metal concentrations were measured and then a risk assessment was performed using the Korean soil-contamination risk assessment guidelines. Cancer risk was the highest from inhalation of Pb-contaminated soil, followed in descending order by As-contaminated soil inhalation and water ingestion. The sum of carcinogenic risks was $3.35{\times}10^{-3}$. The noncarcinogenic risk was observed for inhalation of Hg-contaminated soil (5.71). CONCLUSION: Inhalation of soil in dust was the principal pathway to cause the health risk and most of the risk was attributed to As, Pb,Cd, and Hg contamination.

• Environmental Analysis Health and Toxicology
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• 제16권1호
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• pp.35-41
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• 2001

Barley or corn tea, which is usually prepared with municipal chlorinated tap water, is commonly consumed by the public as a substitute for the supplied water itself. This is because most people believe that harmful organic and inorganic compounds can be removed from the tap water by the adsorption mechanism during the tea preparation. In this study, three kinds of commercial grain tea materials-roasted barley grains, a tea bag containing barley grain pieces, and roasted corn grains-were tested for metal removal by preparing 1 liter of tea with deionized/distilled water according the manufacturer's recommended preparation procedures, assuming that the water is contaminated with eight selected metals at levels of 50$\mu\textrm{g}$/l. Of the tested teas, barley tea prepared with roasted grains showed the highest removal efficiency for Cu, As, Ni, Co, Pb, and Cd, ranging from 48 to 71%, followed by corn tea with roasted grains and barley tea with a tea bag. Cr was nearly maintained at the initial concentration in all kinds of tea. The Mn levels. however, were elevated during the tea preparation, particularly in both barley teas, probably because the metal was extracted into the water from the tea materials without significant adsorption. Therefore, it should be considered in the ingestion exposure analysis for metals that their concentrations are altered during the tea preparation with roasted barley or corn grain materials.

• Journal of Ginseng Research
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• 제34권3호
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• pp.219-226
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• 2010

In the present study, we investigated whether a gross deletion in the nef gene ($g{\Delta}nef$) is induced by Korean red ginseng (KRG) intake. Ten patients were treated with KRG powder for 3 years in the absence of antiretroviral drug therapy. On average, $3,555{\pm}1,042\;g$ KRG was administered per person over $36.1{\pm}2.4$ months. There was a mild decrease in CD4 T cell count ($75{\pm}110/{\mu}L$) over the $36.1{\pm}2.4$ months (p = 0.059). We obtained 355 nef amplicons using 71 peripheral blood mononuclear cell samples over a 3-year period. All ten patients exhibited g${\Delta}$nef (range, 3.2 to 45.9%). At baseline, 3 of 78 amplicons (3.8%) exhibited $g{\Delta}nef$, whereas 18.8% (52/277) revealed $g{\Delta}nef$ during KRG-intake (p<0.001). The proportion of $g{\Delta}nef$ was significantly correlated with monthly dose of KRG (r=0.89, p<0.001). The median time for first detection of $g{\Delta}nef$ was 13 months. In conclusion, our data show that $g{\Delta}nef$ is inducible by KRG intake and its proportion is dependent on the duration of KRG intake and dose of KRG.

• 한국전기전자재료학회논문지
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• 제24권9호
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• pp.760-765
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• 2011

Znic sulfide (ZnS) thin films were deposited on glass substrates by radio frequency magnetron sputtering. The substrate temperature varied from room temperature (RT) to $500^{\circ}C$. The structural and optical properties of ZnS films were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive analysis of X-ray (EDAX) and UV-visible transmission spectra. The XRD analyses reveal that ZnS films have cubic structures with (111) preferential orientation, whereas the diffraction patterns sharpen with the increase in substrate temperatures. The FESEM images indicate that ZnS films deposited at $400^{\circ}C$ have nano-sized grains with a grain size of ~ 67 nm. Then films exhibit relatively high transmittance of 80% in the visible region, with an energy band gap of 3.71 eV. One obvious result is that the energy band gap of the film increases with increasing the substrate temperatures.

• 한국농공학회논문집
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• 제47권1호
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• pp.71-77
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• 2005

Recycling of reclaimed concrete (RC) is very important in the management of construction and demolition wastes. Most of RC is utilized for land-filling after crushing in this country. In this study, a series of elution experiments were conducted to investigate the type and amount of pollutants released from the crushed RC. Most water quality parameters including heavy metals and some organic compounds were below standards for drinking water. Some of heavy metals such as As, Cd, Pb, Hg were detected in 0.5 N H2S04 solution after 24-hour immersing RC, which was conducted for evaluating a long term release effect. The concentration of the heavy metals were higher than the drinking water standards. The results also showed significant adsorption of heavy metals by crushed Re. Potential risks, based on the result of this study were not high in using crushed RC for land-filling. Appropriate management of RC would reduce the risk, for example the separation of hazardous materials from construction wastes. Long term evaluations for the sites of land filled with RC would be required to assess the environmental impacts.