• Economic and Environmental Geology
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• v.32 no.4
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• pp.385-398
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• 1999

The Narim gold mine is located approimately 200km southeast of Seoul within the Muju mineralized district of the Sobaegsan gneiss complex, Korea. Environmental geochemistry were undertaken for various kinds of water (surface, ground and mine water) collected of April, September and November in 1998 from the narim mine creek. Hydrogeochemical compositions of water samples are characterized by the relatively significant enrichment of Na+K, alkali ions, $HCO_{3}$, $NO_{3}$, Cl and F in groundwater, wheras the mine and surface waters are relatively enriched in Ca+Mg, hea표 metals and $SO_{4}$. Therefore, the groundwaters belong to the (Na+Ca)-( $HCO_{3}+SO_{4}$) type, respectively. The pH and EC values of the non-mining creek surfers are relatively lower compared with those of the surface water of the mine and ore dump area. The d values ($\delta$D-8$\delta^{18}$O) of all kinds of water from the Narim mine creek are 5.8 to 13.1 The range of $\delta$D and $\delta^{18}$O values (relative to SMOW) are shown in distinct two groups as follows: for the April waters of -64.8 to -67.8$\textperthousand$ and -9.6 to -10.0$\textperthousand$(d value=10.1 to 13.1), and for the November waters of -65.9 to -70.2$\textperthousand$ and -9.3 to -9.6$\textperthousand$ (d value=5.8 to 7.9), respectively. This range variation indicates that two group water were composed of distinct waters with seasonal difference. Geochemical modeling showed that mostly toxic metals (As, Fe, Mn, Ni, Pb, Zn) may exist largery in the from of metal $(M2^+)$ and metal-sulfate $(MSO_4\;^{2-$\mid$),\; and \;SO_4^{2-$\mid$}$ concentration influenced the speciation of heavy metals in the meteoric water. These metals in the groundwater could be formed of $CO_3 \;and \;(OH)_3$ complex ions. Using computer program, saturation index of albite, calcite, dolomite in meteoric water show undersaturated and progreddively evolved toward the saturation state, however, ground and mine water are nearly saturated. The gibbsited water-mineral reaction and stabilities suggest that the weathering of silicate minerals may be stable kaolinite, illite and Nasmectite. The clay minerals will be transformed to more stable kaolinite owing to the contiunous reaction.

• Korean Journal of Soil Science and Fertilizer
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• v.51 no.1
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• pp.35-49
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• 2018

This study was initiated to quantitatively evaluate the effects of five heavy metals (Cd, Cu, Zn, Pb, and Ni) on growth and P removal efficiencies of Pseudomonastaeanensis, known as the phosphorus accumulating microorganism. The heavy metals were added individually and with the binary mixture to the batch culturing system of Pseudomonastaeanensis. $IC_{50}$ and $EC_{50}$ were used to quantitatively evaluate their effects on the growth and phosphorus removal efficiency of Pseudomonas taeanensis in those treatments. Additionally, additive index value method was used to evaluate the interactive effects of heavy metals for Pseudomonas taeanensis in this study. As those heavy metals were singly added to Pseudomonastaeanensis, the greatest inhibitory effect on its growth and P removal efficiency was observed in Cd, whereas, the smallest effect was found in Ni. As the concentrations of all heavy metals added were gradually increased, its growth and P removal efficiency was correspondingly decreased. Specifically, $IC_{50}$ of Pseudomonas taeanensis for Cd, Cu, Zn, Pb, and Ni were $0.44mg\;L^{-1}$, $5.12mg\;L^{-1}$, $7.46mg\;L^{-1}$, $8.37mg\;L^{-1}$ and $14.56mg\;L^{-1}$, respectively. The P removal efficiency of Pseudomonas taeanensis was 81.1%. $EC_{50}$ values of Pseudomonas taeanensis for Cd, Cu, Zn, Pb, and Ni were $0.44mg\;L^{-1}$, $4.08mg\;L^{-1}$, $7.17mg\;L^{-1}$, $8.90mg\;L^{-1}$ and $11.26mg\;L^{-1}$, respectively. In the binary treatments of heavy metals, the lowest $IC_{50}$ and $EC_{50}$ were found in the Cd + Cu treatment, whereas, the highest $IC_{50}$ and $EC_{50}$ were found in the Zn + Pb and Pb + Ni treatments, respectively. Most of the interactive effects for the binary mixture treatments of heavy metals were antagonistic. Based on the results obtained from this study, it appears that they could provide the basic information about the toxic effects of the respective individual and binary treatments of heavy metals on the growth and P removal efficiency of other phosphorus accumulating organisms.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.1-6
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• 2004

Agricultural recycling of livestock wastes by composting has lots of beneficial effects on crop production and soil fertility. Most of composts are made from pig manure and water content controller such as saw dust, bark, rice hulls etc. by aerobic processing. But the insufficient supply of saw dust, bark etc. cause the indiscreet use of industrial waste having heavy metals and toxic synthetic chemicals. This research investigated the present quality status of organic by-product fertilizers, and suggested the way of quality interpretation under the statistical approaches based on median, mean and weighted average value. Since the data of one hundred of samples for heavy metal contents (Cd, Pb, Cu, and Cr) and OM/N showed extremely left-skewed distribution, the median was more useful than the mean in representing the characteristics of distribiition for each items. The weighted average value will be a useful index for the quality based on the total amount of producing.

• Fire Science and Engineering
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• v.15 no.1
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• pp.100-107
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• 2001

A Interior material, a main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Nonetheless, it has been used recklessly with undue attention to its contribution to fire in particular in entertainment occupancy and causes many victims in fire. Therefore, this study attempts to examine the current use of interior material in Korea and find out what to be improved and enhanced in terms of related regulations. Based on the comparison and analysis of the Korea regulation with those of advanced nations, suggestions are made for an effective and efficient improvement and complement to the current system. What can be suggested from this study are as follows. The use of interior material should be controlled under the unified regulation of fire-safety codes. Code should be set up so that the current construction enforcement should be applied in retroactive to those entertainment buildings that obtained a license prior to the implementation of the system certifying that the building is fire-resistant and fire-protective. The legislation should be made to control the fire-protection facilities of small-sized, underground entertainments. It should be obliged to present the blueprint displaying the use of interior material at the time of changing occupancy. Or, it should be compelled to report changes that go way without permit to the administrative office. A compulsory provision should be set up to have a fire-resistant performance to movable furniture. The classification index designating the fire hazard of interior material by flame spread rate and smoke toxicity and its test method should be established.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.52-57
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• 1996

This experiment was carried out to evaluate the effect of sublethal doses of BPMC, etofenprox,and buprofezin on N. lugens. and its predator C. lividipennis. Buprofezin was found to be the most toxic to N. lugens and the most safe to C. lividipennis among the three insecticides, based on LD50 values. Selective toxicity index calculated by dividing LDSo value of C. lividipennis by that of N. lugens indicated that buprofezin was very safe to C. lividipennis, showing selective toxicity of 2703.3. Longevity and fecundity of N. lugens treated with LDIU and LDm of buprofezin and BPMC were not significantly different with those of untreated brown planthoppers. However, egg hatchability' of N. lugens was greatly reduced when treated with LDm of buprofezin, having the highest inhibition rate of 17.7%. Hatchability of eggs from insects treated with BPMC was similar to that of control. The oviposited peak of treated hoppers appeared late as compared to the untreated which showed the peak at early part of the ovipositional period. The longevity and fecundity of C. lividipennis treated with BPMC were significantly reduced as compared with the untreated. Etofenprox also induced fecundity reduction when treated with LDlo, and LDm. However, C. lividipennis treated with sublethal doses of buprofezin showed no redution in logevity and fecundity. From these results, it may be said that buprofezin can be used to control brown planthopper without disrupting of C. lividipennis population in the rice field.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.58-65
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• 1996

This experiment was carried out to evaluate the effect of sublethal doses of BPMC, etofenprox, and buprofezin on N. lugens. and its predator C. lividipennis. Buprofezin was found to be the most toxic to N. lugens and the most safe to C. lividipennis among the three insecticides, based on LD50 values. Selective toxicity index calculated by dividing LDSo value of C. lividipennis by that of N. lugens indicated that buprofezin was very safe to C. lividipennis, showing selective toxicity of 2703.3. Longevity and fecundity of N. lugens treated with LDIU and LDm of buprofezin and BPMC were not significantly different with those of untreated brown planthoppers. However, egg hatchability' of N. lugens was greatly reduced when treated with LDm of buprofezin, having the highest inhibition rate of 17.7%. Hatchability of eggs from insects treated with BPMC was similar to that of control. The oviposited peak of treated hoppers appeared late as compared to the untreated which showed the peak at early part of the ovipositional period. The longevity and fecundity of C. lividipennis treated with BPMC were significantly reduced as compared with the untreated. Etofenprox also induced fecundity reduction when treated with LDlo, and LDm. However, C. lividipennis treated with sublethal doses of buprofezin showed no redution in logevity and fecundity. From these results, it may be said that buprofezin can be used to control brown planthopper without disrupting of C. lividipennis population in the rice field.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.377-382
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• 2011

This test was performed to evaluate the acute oral toxicity and skin irritation of Lamia-Kill$^{(R)}$, disinfectant, containing 20% benzalkonium chloride and 10% citric acid. In acute oral toxicity, Lamia-Kill$^{(R)}$ was orally administered at dose levels of 2,000, 1,000, 500, 250 and 0 mg/kg body weight. After single oral administration to both sexes of SD rats, the rats were observed for 14 days. In primary skin irritation test, New Zealand white rabbits were dermally treated with Lamia-Kill$^{(R)}$ for 24 hr and observed for 3 days. All rats treated with Lamia-Kill$^{(R)}$ were induced no toxic signs in mortalities, clinical findings, body weights and gross findings. Also, the disinfectant did not induce any adverse reactions such as erythema and edema on intact skin sites for the most part rabbits, but on abraded skin sites, some rabbits showed very slight erythema on 24 hr after topical application. With the results of this study, Lamia-Kill$^{(R)}$ have no effect on acute toxicity and side effect in SD rats and was classified as a practically non-irritating material based on the score 0.50 of primary irritation index.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3651-3657
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• 2014

Hepatocellular carcinoma (HCC) has a relatively higher incidence in many countries of Asia. Globally, HCC has a high fatality rate and short survival. Epirubicin, a doxorubicin analogue, may be administered alone or in combination with other agents to treat primary liver cancer and metastatic diseases. However, the toxic effects of epirubicin to normal tissues and cells have been one of the major obstacles to successful cancer chemotherapy. Here, we investigated the effects of epirubicin in combination with kappa-selenocarrageenan on mice with H22 implanted tumors and HepG-2 cell proliferation, immune organ index, morphology, cell cycle and related protein expressions in vivo and in vitro with sequential drug exposure. The inhibitory rate of tumor growth in vivo was calculated. Drug sensitivity was measured by MTT assay, and the King's principle was used to evaluate the interaction of drug combination. Morphological changes were observed by fluorescent microscopy. Cell cycle changes were analyzed by flow cytometry. Expression of cyclin A, Cdc25A and Cdk2 were detected by Western blotting. In vivo results demonstrated that the inhibitory rate of EPI combined with KSC was higher than that of KSC or EPI alone, and the Q value indicated an additive effect. In addition, KSC could significantly raise the thymus and spleen indices of mice with H22 implanted tumors. In the drug sensitivity assay in vitro, exposure to KSC and EPI simultaneously was more effective than exposure sequentially in HepG-2 cells, while exposure to KSC prior to EPI was more effective than exposure to EPI prior to KSC. Q values showed an additive effect in the simultaneous group and antagonistic effects in the sequential groups. Morphological analysis showed similar results to the drug sensitivity assay. Cell cycle analysis revealed that exposure to KSC or EPI alone arrested the cells in S phase in HepG-2 cells, exposure to KSC and EPI simultaneously caused accumulation in the S phase, an effect caused by either KSC or EPI. Expression of cyclin A, Cdc25A and Cdk2 protein was down-regulated following exposure to KSC and EPI alone or in combination, exposure to KSC and EPI simultaneously resulting in the lowest values. Taken together, our findings suggest that KSC in combination with EPI might have potential as a new therapeutic regimen against HCC.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.497-507
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• 2011

This research studied human health risk assessment of benzene from industrial complexes of Chungcheong Province (Seosan industrial complex) and Jeonla Province (Iksan industrial complex and Yeosoo industrial complex). The residents near the industrial complexes areas can be often exposed to volatile organic compounds (e.g., benzene, toluene, xylenes) through a number of exposure pathways, including inhalation of the organic pollutant via various environmental matrices (air, water and soil), contaminated water, and soil intake. Benzene is well known to be a common carcinogenic and toxic compound that is produced from industrial and oil refinery complexes. In this study, a number of samples from water, air, and soil were taken from the residential settings and public school zones located near the industrial complex sites. Based on the carcinogenic risk assessment, the risk estimates were slightly above $10{\times}10^{-6}$ at all three industrial sites. According to deterministic risk assessment, inhalation was the most important route. The distribution of benzene in the environment would be dependent on vapor pressure, and the physical property influencing the extent of the potential risks. Non-carcinogenic risk assessment of benzene shows that the values of Hazard Index(HI) were much lower than 1.0 at all industrial complexes. Therefore, benzene was not a cause of concern in terms of non-carcinogenic risk posed to the residents near the sites. When compared to probabilistic risk assessment, the CTE(central tendency exposure) cancer risk values of deterministic risk assessment were close to the mean values predicted by the probabilistic risk assessment. The RME(reasonable maximum exposure) values fell within the range of 95% to 99.9% estimated by the probabilistic risk assessment. Since the values of carcinogenic risk assessment were higher than $10{\times}10^{-6}$, further detailed monitoring and refined risk assessment for benzene may be warranted to estimate more reliable and potential inhalation risks to receptors near the industrial complexes.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.2
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• pp.68-74
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• 2009

Polycyclic aromatic hydrocarbons (PAHs), one of ubiquitous organic pollutants in marine environments, are major toxic components of petroleum and are produced during the incomplete combustion of organic materials. As shipyards are located inside of natural or artificial semi-enclosed bay, even a relatively weak environmental disturbance by ship-building activity can cause severe damage to marine ecosystem in the bay. Many studies of pollution in shipyard area have been focused on the antifouling agent, like tributyltin. This study aimed to investigate the effect of ship-building activity on PAH contamination. Total PAHs concentration was higher nearby and inside shipyard area than outside, implying that shipyard could be one of major source area of PAH contamination to pose harmful effects to surrounding environments. Through PAH profile and source recognition index, the source of PAHs inputs in this area was estimated to originate from both petrogenic and pyrogenic origin. PAH levels showed a significant correlation with total butyltins, indicating that ship-building activity influenced PAH concentration and distribution. Vertical distribution of PAHs historically confirmed the correlation between shipbuilding activity and PAHs contamination.