• Economic and Environmental Geology
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• v.30 no.3
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• pp.209-222
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• 1997

The Hoenam area, up the Taecheong lake, composed mainly of low grade coal-bearing metapelites within the Ogcheon Supergroup. These coal formations are developed discontinuously several hundred meters and swelling from 10 to 300 cm along the host metapelites. Although the formations have been mined for coal, but already mined out, and the formations were higher content (mean value of 42 samples) of environmental toxic elements as As (13 ppm). Ba (1.81 wt. %), Cd (2 ppm), Cr (188 ppm), Cu (87 ppm), Mo (214 ppm), Pb (25 ppm), Sb (3 ppm), Se (12 ppm), U (55 ppm), V (2124 ppm) and Zn (234 ppm) than the host metapelites and the NASC. The Al, Ti, Mg, K and Na contents in stream sediments derived from the Hando and Bugook mine area were highly concentrations than the samples from the Samseongjeil mine area. The mean value (wt. %) of Fe (10.07), Mn (0.15), Ca (0.84), P (0.18) and Ba (0.77) influenced by the Samseongjeil mine were higher than the other mine drainage sediments. The mean content (ppm) of environmental toxic elements in drainage sediments from the Samseongjeil mine were taken As (2083), Cu (447), Mo (202), Ni (720), Pb (42), U (250), V (1070) and Zn (2632), which are extremely high concentrations against NASC and EPA. Characteristics of elemental behavior and dispersion of the all toxic elements are the same as increased with increasing U, V, and Cu. Rare earth elements in the sediments are enriched with LREE (La, Ce and Nd) from the drainage on strong concentration of toxic elements. The pH of stream water is neutral, but pH of the sediments ranged from 4.92 to 6.93 (mean 6.22), those are slightly acid in the Hando mine area. Major elements in the host rocks at the Hoenam area are mostly depleted especially Ca, excepting Ti and Ba, normalized with NASC. The sediments were highly enriched of Ti, Fe, Mg, Mn and Ba, but depleted of Al, K, Ca, Na and P on the basis of host rocks and NASC. Minor and environmental toxic elements in the host rocks were strongly enriched all elements (As, Cd, Mo, Se, D, V and Zn), excepting Co, Ni and Sr. Enrichment index (mean value) about toxic elements (As, Cr, Cu, Fe, Ni, Pb and Zn) of the sediments in this area have taken 41.35 (Hando mine drainage; 2.73, Samseongjeil mine drainage; 113.14 and Bugook mine drainage; 8.19), those are seriously contaminated by environmental toxic elements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.73-82
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• 2017

In Korea, previous certification of water supply infrastructure was mainly focused on economical and physical aspects. Recently, hygienic safety of water supply service has become a sensitive and important issue to our people for evaluating the water quality with growth of economy and education system. According on water quality in 497 Korean water supply facilities, pH values in the supplied water have ranged between 5.8-8.5. However, little is known about metal leachability at the pH conditions observed in the real water supply systems because a fixed pH condition (pH 7.0) has been used in the current standard method, 'Hygienic Safety Testing Method', in water supply. In this work, we examined the effects on heavy metal leachability with pH differences in the water supply pipes which are typically used in Korea. As a result, the amounts of metal leachability were tended to increase when pH levels were decreased. Especially at pH 5.8, Cu leachability from Cu pipes was found to exceed the public health standard level even after applying a normalization factor (NF) given by the current Korea standard method. The Cr and Cu leached from stainless steel pipes, Cd, Pb, Cu, and Zn from Cu-based pipe fittings, and Zn from Zn-based pipe fittings were exceeded the Korean hygienic safety standards while, after applying the NF, concentrations of the leached metals were satisfied with the current Korean standard. The findings from this work provide implications on the needs of reforming the current hygienic safety standard methodology.

• Analytical Science and Technology
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• v.27 no.2
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• pp.114-120
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• 2014

The aim of this study was to investigate of total ash, acid-insoluble ash and heavy metals content contained in commercial herbal medicines classified by parts used. A total of 1504 samples (84 species) purchased from markets in Seoul, are classified by five kinds of plant parts. The mean of total ash and acidinsoluble ash content (%) were as follows; Herba 9.0, 1.1, Caulis and cortex 6.1, 1.0, Flos fructus and semen 5.1, 0.8, Radix 4.6, 0.7 and Rhizoma 4.3, 0.4. The total amount of individual heavy metals content (mg/kg) (Pb, As, Cd and Hg) was high in Herba 1.13 and decreased in the order of Caulis and cortex 1.07, Rhizoma 0.91 and Radix 0.91, and was low in Flos fructus and semen 0.73. In addition, acid-insoluble ash contents was correlated with the total amount of individual heavy metals (r=0.314) (p<0.01).

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1052-1062
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• 2011

Residual of heavy metals originated from abandoned metal mines in agricultural field can cause adverse effect on ecosystem and eventually on human health. For this reason, remediation of heavy metal contaminated agriculture field is a critical issue. In this study, five different amendments, agriculture lime, dolomite, steel slag, zeolite, and compost, were evaluated for stabilization efficiency of heavy metals in agricultural field. Applied mixing ratio of amendments was varied (2% or 6%) depending on properties of amendments. Result showed that soil pH was increased compared to control (6.1-6.7) after mixing with amendments and ordered as dolomite (7.2~8.3) > steel slag (6.7~8.1) > agriculture lime (6.6~7.4) > zeolite (6.2~6.9) > compost (6.1~7.1). Among other amendments, agriculture lime, steel slag, and dolomite showed the highest stabilization efficiency of heavy metals in soil. For Cd, stabilization efficiency was 49~72%, 51~83%, and 0~36% for agriculture lime, steel slag, and dolomite respectively. In case of Pb, 43~64, 37~73%, and 51~73% of stabilization efficiency was observed for agriculture lime, steel slag, and dolomite respectively. However, minimal effect of heavy metal stabilization was observed for zeolite and compost. Based on result of this study, amendments that can increase the soil pH were the most efficient to stabilize heavy metal residuals and can be adapted for remediation purpose in agricultural field.

• Journal of Nutrition and Health
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• v.44 no.6
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• pp.518-526
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• 2011

To determine blood heavy metal concentrations by seafood consumption in Korean adults, blood cadmium, mercury, and lead concentrations in a representative sample of 1,709 Koreans participated in the Fourth Korea National Health and Nutrition Examination Survey (KHANES IV-2) in 2008 were analyzed by age and seafood consumption frequency. The mean blood cadmium, mercury, and lead concentrations were $1.14{\pm}0.73{\mu}g/L$, $5.50{\pm}3.83{\mu}g/L$, and $2.56{\pm}1.22{\mu}g/dL$, respectively. The subjects aged ${\geq}$ 50 years had significantly higher blood cadmium concentrations than the subjects aged 20~39 years. Blood mercury concentrations of the 50's were significantly higher than those of the 20's and 30's (p < 0.05). Approximately, 43% of males and 22% of females had blood mercury concentrations > $5.8{\mu}g/L$ which is a blood mercury level equivalent to the current Reference Dose. Only 2 subjects had lead concentrations > $10{\mu}g/dL$, the standard lead level by the Centers for Disease Control and Prevention, USA. The subjects consuming pollack, mackerel, anchovy, corvina, shellfish, and salted seafood at least once a week had significantly higher mercury concentrations than the subjects consuming those seafoods less than once a month. However, there were no clear relationships between blood cadmium and lead concentrations and seafood consumption frequencies.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.91-96
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• 2012

Objectives: To determine the prevalence of HPV and cervical neoplasia among HIV-infected women in southwestern China. Methods: Cervical cytology, HPV detection by Hybrid Capture-$2^{TM}$ assay, and diagnostic colposcopy were followed by cervical biopsy if indicated. Logistic regression analysis was used to analyze associations between HPV co-infection and cervical intraepithelial neoplasia (CIN), and HIV-related clinical and laboratory parameters. Results: Colposcopic-histopathologically proven CIN2+ lesions were present in 7/83 (8.4%) HIV-infected women. Nearly half (41/83, 43%) were co-infected with carcinogenic HPV genotypes. HPV co-infection was higher in women with colposcopic-histopathologically proven CIN2+ lesions than women with $cells/{\mu}L$ had higher CIN2+ prevalence after adjusting for current ART status and age (adjusted OR: 6.3, 95% CI: 1.1, 36.5). Conclusions: HIV/AIDS care and treatment programs should integrate effective cervical cancer prevention services to mitigate the risk of invasive cervical cancer among HIV-infected women in China.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.41-47
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• 2014

This study was conducted to investigate the content of foreign mineral materials and heavy metals (Pb, As, Cd, Hg) contained in commercial herbal medicines (1504 samples) classified by parts used, and the effect of removing heavy metals by washing treatment (take 50 g of the sample and put 1000 ml of distilled water, shake it gentle by hand for 1 min). The 5% trimmed means of acid-insoluble ash value (%) were as follows; above ground parts (0.76) and underground parts (0.52). Those of the total amount of individual heavy metals value (mg/kg) were as follows; caulis (1.33), flos (1.23), herba (0.91), cortex (0.76), rhizoma (0.73), radix (0.67), semen (0.44) and fructus (0.39). Acid-insoluble ash content was correlated with Pb in herbal medicines of underground parts (r=0.446) (p<0.01). After washing, the removal rate of heavy metals contained in 6 radix herbal medicines shows 33-13% respectively.

• Journal of Microbiology and Biotechnology
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• v.5 no.2
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• pp.68-73
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• 1995

Pseudomonas sp. P20 was shown to be capable of degrading biphenyl and 4-chlorobiphenyl (4CB) to produce the corresponding benzoic acids wnich were not further degraded. But the potential of the strain for biodegradation of 4CB was shown to be excellent. The pcbA, B, C and D genes responsible for the aromatic ring-cleavage of biphenyl and 4CB degradation were cloned from the chromosomal DNA of the strain. In this study, the pebC and D genes specifying degradation of 2, 3-dihydroxybiphenyl (2, 3-DHBP) produced from biphenyl by the pebAB-encoded enzymes were cloned by using pBluescript SK(＋) as a vector. From the pCK102 (9.3 kb) containing pebC and D genes, pCK1022 inserted with a EcoRI-HindIII DNA fragment (4.1 kb) carrying pebC and D and a pCK1092 inserted with EcoRI-XbaI fragment (1.95 kb) carrying pebC were constructed. The expression of pcbC and D' in E. coli CK102 and pebC in E. coli CK1092 was examined by gas chromatography and UV-vis spectrophotometry. 2.3-dihydroxybiphenyl was readily degraded to produce meta-cleavage product (MCP) by E. coli CK102 after incubation for 10 min, and then only benzoic acid(BA) was detected in the 24-h old culture. The MCP was detected in E. coli CK1022 containing pebC and 0 genes (by the resting cells assay) for up to 3 h after incubation and then diminished completely in 8 h, whereas the MCP accumulated in the E. coli CK1092 culture even after 6 h of incubation. The 2, 3-DHBP dioxygenases (product of pebC gene) produced by E. coli CK1, CK102, CK1023, and CK1092 strains were measured by native PAGE analysis to be about 250 kDa in molecular weight, which were about same as those of Pseudomonas sp. DJ-12, P. pseudoa1caligenes KF707, and P. putida OU83.

• Polymer(Korea)
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• v.34 no.1
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• pp.69-73
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• 2010

Effects of reaction time and temperature on the isomerization and dehydrobromination reactions of brominated butyl rubber were investigated. The structural composition of brominated butyl rubber was determined by Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy($^1H$-NMR), Density functional theory (DFT) was used to study on the isomerization and dehydrobromination mechanisms of model compounds. The geometries for model compounds of 3-bromo-5,5,7,7-tetramethyl-2(2',2',4',4'-tetramethyl)pentyl-1-octylene (3BrOE), 1-bromo-5,5,7,7-tetramethyl-2(2',2',4',4'-tetramethyl)pentyl-2-octylene (1Br2OE) and 5,5,7,7-tetramethyl-2(2',2', 4',4'-tetramethyl)pentyl-1,3-octadiene (CD) had been optimized by using density functional theory at B3LYP/3-21G and B3LYP/6-31G levels. The predicted energy of 3BrOE lies higher than that of 1Br2OE which suggests that 1Br2OE configuration is more stable than the 3BrOE configuration. Compared with the energy barrier, the pathway of dehydrobromination is less competitive than that of isomerization. This is qualitatively consistent with the experimental results.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.478-483
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• 2010

This study was conducted to investigate the physico-chemical properties of Schizandra chinensis Baillon orchard soils located in Jangsu-gun, Jeollabuk-do. Surface (0 to 10 cm) soils were collected from 200 experimental sites located at Jangsu-eup (53 site), Gyenam-myeon (31), Chunchun-myeon (73), Janggye-myeon (12), Bunyam-myeon (31). The soil texture was mostly loamy sand, and the mean values of degree of soil aggregate and soil porosity were 33.1 and 59.9%, respectively. The pH, EC, total-N, available-P, soil organic matter, and cation exchange capacity of the soils were $5.51{\pm}0.54$, $290{\pm}139{\mu}S\;cm^{-1}$, $946.3{\pm}65.5mg\;kg^{-1}$, $319.6{\pm}29.2mg\;kg^{-1}$, $29.0{\pm}13.9g\;kg^{-1}$ and $4.11{\pm}0.34cmol_c\;kg^{-1}$, respectively. The concentrations of Pb, Cd, Cu and Zn were $3.48{\pm}0.55$, $0.09{\pm}0.04$, $6.90{\pm}0.91$ and $97.7{\pm}42.2mg\;kg^{-1}$, respectively. The presented data can be utilized in better managing Schizandra chinensis Baillon orchard soils in the studied areas.