• Title/Summary/Keyword: Long-Term Experiment

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The Morphologic Changes by Immunosuppression after Heterotopic Transplantation of the Murine Cryopreserved Trachea: An Animal Model for Obliterative Bronchiolitis (이소 이식된 쥐 기관의 면역억제 및 초냉동 보관에 의한 형태학적 변화: 폐색성 모세기관지염의 연구를 위한 동물 실험 모델)

  • 이창하;성숙환;오미혜
    • Journal of Chest Surgery
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    • v.32 no.3
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    • pp.215-223
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    • 1999
  • Background: The replacement of the narrowed long-segment trachea with various prosthetic materials or tissue grafts remains a difficult and unsolved surgical problem. Homologous cryopreserved tracheal transplantation has been considered to treat the irreversibly-damaged organs, such as in the lung or heart transplantation and also to overcome the limited supply of donor organs. We examined the morphological changes and the immunosuppressive effects of the cryopreserved trachea after the heterotopic transplantation in the rats. Material and Method: Sixty tracheal segments harvested from 30 donor Wistar rats were heterotopically implanted into the peritoneal cavity of 20 recipient Wistar rats and 40 Sprague Dawley rats. The 60 recipient rats were divided into 6 groups(10 rats/ group). In groups I, II, and III, 30 tracheal segments were implanted immediately after the harvesting and in groups IV, V, and VI, the segments were implanted 28 days after the cryopreservation. Groups I and IV were Wistar syngeneic controls. Groups II and V were Sprague Dawley recipients receiving no immunosuppression and Groups III and VI, were Sprague Dawley recipients receiving immunosuppressive agents. At 28 days all rats were sacrificed and the tracheal segments were evaluated grossly and histologically. Result: Immunosuppression of the tracheal segments had a significant influence on the changes of the tracheal lumen and tracheal epithelial cells, irrespective of the cryopreservation of the trachea(p<0.001). In groups III and VI receiving immunosuppressive agents, the tracheal lumen was patent and the normal epithelial cells were observed, however in the other groups not receiving the immunosuppressive agents, there were almost luminal obliteration by the proliferation of the fibrous tissues and a loss of the epithelial cells, the findings were similar to those in the case of obliterative bronchiolitis after a lung and a heart-lung transplantation. Conclusion: With the appropriate immunosuppressive agents, the lumen and the respiratory epithelium of the transplanted tracheal segment were well preserved, even after the cryopreservation of the tracheal segment, which shows the possibility of the long-term preservation and homologous transplantation of the trachea. But fibroproliferative obliteration of the tracheal lumen and the loss of the normal respiratory epithelial cells, characteristic findings of obliterative bronchiolitis, were observed in the groups without the immunosuppression. This experiment using the rat trachea may be useful in studying the pathogenesis, treatment, and prevention of obliterative bronchiolitis after a lung and a heart-lung transplantation.

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Influence of Dissolved Ions on Geochemical Dissolution of Uranium in KURT Granite (KURT 화강암 내 우라늄의 지화학적 용출특성에 미치는 용존이온의 영향)

  • Cho, Wan Hyoung;Baik, Min Hoon;Ryu, Ji-Hun;Lee, Jae Kwang
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.3
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    • pp.281-290
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    • 2018
  • In order to understand the long-term behavior of radionuclides in granite environments, geochemical behavior characteristics of uranium in granitic host rock of KURT (KAERI Underground Research Tunnel) were investigated by dissolution experiment with different reaction time and solutions. In the dissolution experiment, significantly increased dissolution levels of uranium from granite powder samples were identified during the reaction time of 0~10 days for reaction solutions ($UD-CO_3$ and UD-Bg) containing a large amount of $CO_3{^{2-}}$. On the other hand, significantly increased dissolution levels of uranium were also identified for reaction solutions containing Na and Ca after 60 days. Dissolution of uranium continuously increased in reaction solutions of $UD-CO_3$ ($44.61{\mu}g{\cdot}L^{-1}$), UD-Bg ($41.01{\mu}g{\cdot}L^{-1}$), UD-Na ($26.87{\mu}g{\cdot}L^{-1}$), UD-Ca ($20.26{\mu}g{\cdot}L^{-1}$), UD-CaSi ($17.03{\mu}g{\cdot}L^{-1}$), and UD-Si ($10.47{\mu}g{\cdot}L^{-1}$) in the experimental period of ~270 days. However, after day 270, dissolution of uranium showed a decreasing tendency. This is thought to have occurred because existing uranium in granite samples reached the limit of dissolution by interaction with reaction solutions. Concentrations of dissolved uranium and points of maximum concentration value were found to differ depending on the $CO_3{^{2-}}$ presence in the mixed reaction solution and on the geochemical type of the water. It is estimated that differences in the reaction rate between the granite sample and the reaction solution are due to the influence of dissolved ions in the reaction solution.

Korean Ocean Forecasting System: Present and Future (한국의 해양예측, 오늘과 내일)

  • Kim, Young Ho;Choi, Byoung-Ju;Lee, Jun-Soo;Byun, Do-Seong;Kang, Kiryong;Kim, Young-Gyu;Cho, Yang-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.2
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    • pp.89-103
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    • 2013
  • National demands for the ocean forecasting system have been increased to support economic activity and national safety including search and rescue, maritime defense, fisheries, port management, leisure activities and marine transportation. Further, the ocean forecasting has been regarded as one of the key components to improve the weather and climate forecasting. Due to the national demands as well as improvement of the technology, the ocean forecasting systems have been established among advanced countries since late 1990. Global Ocean Data Assimilation Experiment (GODAE) significantly contributed to the achievement and world-wide spreading of ocean forecasting systems. Four stages of GODAE were summarized. Goal, vision, development history and research on ocean forecasting system of the advanced countries such as USA, France, UK, Italy, Norway, Australia, Japan, China, who operationally use the systems, were examined and compared. Strategies of the successfully established ocean forecasting systems can be summarized as follows: First, concentration of the national ability is required to establish successful operational ocean forecasting system. Second, newly developed technologies were shared with other countries and they achieved mutual and cooperative development through the international program. Third, each participating organization has devoted to its own task according to its role. In Korean society, demands on the ocean forecasting system have been also extended. Present status on development of the ocean forecasting system and long-term plan of KMA (Korea Meteorological Administration), KHOA (Korea Hydrographic and Oceanographic Administration), NFRDI (National Fisheries Research & Development Institute), ADD (Agency for Defense Development) were surveyed. From the history of the pre-established systems in other countries, the cooperation among the relevant Korean organizations is essential to establish the accurate and successful ocean forecasting system, and they can form a consortium. Through the cooperation, we can (1) set up high-quality ocean forecasting models and systems, (2) efficiently invest and distribute financial resources without duplicate investment, (3) overcome lack of manpower for the development. At present stage, it is strongly requested to concentrate national resources on developing a large-scale operational Korea Ocean Forecasting System which can produce open boundary and initial conditions for local ocean and climate forecasting models. Once the system is established, each organization can modify the system for its own specialized purpose. In addition, we can contribute to the international ocean prediction community.

Emergences of LH Surge Affected by Different Progesterone Levels in Ovariectomized Goats (난소제거된 염소에서 Progesterone 농도의 영향에 의한 LH surge 분비에 미치는 영향)

  • Kim, Seung-Joon
    • Journal of Veterinary Clinics
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    • v.31 no.1
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    • pp.19-24
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    • 2014
  • The purpose of the present study was to determine the priming effects of progesterone that affect the emergence of LH surge mode secretion by three different progesterone levels. In previous studies, we have shown that LH surge occurred in follicular levels of progesterone, whereas there was no surge mode secretion of LH and FSH in either the subluteal or luteal levels of progesterone. In this study, the hypothesis was that the priming effects of progesterone on the timing of the LH surge induced by exogenous estradiol are same between subluteal and luteal levels of progesterone. Long-term ovariectomized Shiba goats that had received implants of estradiol capsules (Day 0) and three different progesterone silastic packet inducing follicular, subluteal and luteal levels of progesterone were divided into three groups such as non-P, low-P and high-P group. Blood samples were collected daily throughout the experiment for the analysis of gonadal steroid hormone levels. On Day 7, all devices of progesterone packets were removed but estradiol capsules were maintained during the experiment, and blood samples were collected at 1 hr interval for 12 h from the time of progesterone removals to determine peripheral changes of estradiol and progesterone concentration. Then all animals were infused estradiol on the Day 7 after 13 h from the removals of progesterone devices with a peristaltic pump into jugular vein at a rate of 3 ${\mu}g/h$ for 36 h. For analysis of peripheral LH and estradiol concentration, blood samples were collected via another jugular vein at 2 h intervals for 52 h (from 4 h before the start of estradiol infusion to 48 h after the start of estradiol infusion). In all animals of the three groups treated with estradiol infusion, an LH surge was expressed but the peak time of LH surge was different. This time interval from estradiol infusion until the peak of LH surge was gradually and significantly extended by the different levels of progesterone treated before estradiol infusions in the three groups.

Development Strategy for New Climate Change Scenarios based on RCP (온실가스 시나리오 RCP에 대한 새로운 기후변화 시나리오 개발 전략)

  • Baek, Hee-Jeong;Cho, ChunHo;Kwon, Won-Tae;Kim, Seong-Kyoun;Cho, Joo-Young;Kim, Yeongsin
    • Journal of Climate Change Research
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    • v.2 no.1
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    • pp.55-68
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    • 2011
  • The Intergovernmental Panel on Climate Change(IPCC) has identified the causes of climate change and come up with measures to address it at the global level. Its key component of the work involves developing and assessing future climate change scenarios. The IPCC Expert Meeting in September 2007 identified a new greenhouse gas concentration scenario "Representative Concentration Pathway(RCP)" and established the framework and development schedules for Climate Modeling (CM), Integrated Assessment Modeling(IAM), Impact Adaptation Vulnerability(IAV) community for the fifth IPCC Assessment Reports while 130 researchers and users took part in. The CM community at the IPCC Expert Meeting in September 2008, agreed on a new set of coordinated climate model experiments, the phase five of the Coupled Model Intercomparison Project(CMIP5), which consists of more than 30 standardized experiment protocols for the shortterm and long-term time scales, in order to enhance understanding on climate change for the IPCC AR5 and to develop climate change scenarios and to address major issues raised at the IPCC AR4. Since early 2009, fourteen countries including the Korea have been carrying out CMIP5-related projects. Withe increasing interest on climate change, in 2009 the COdinated Regional Downscaling EXperiment(CORDEX) has been launched to generate regional and local level information on climate change. The National Institute of Meteorological Research(NIMR) under the Korea Meteorological Administration (KMA) has contributed to the IPCC AR4 by developing climate change scenarios based on IPCC SRES using ECHO-G and embarked on crafting national scenarios for climate change as well as RCP-based global ones by engaging in international projects such as CMIP5 and CORDEX. NIMR/KMA will make a contribution to drawing the IPCC AR5 and will develop national climate change scenarios reflecting geographical factors, local climate characteristics and user needs and provide them to national IAV and IAM communites to assess future regional climate impacts and take action.

Beneficial Effects of Water Extracts of Scutellariae Radix on Immune Function in Mice Fed Alcohol (알코올 섭취한 생쥐에서 황금(黃芩) 열수추출물이 생쥐의 면역기능에 미치는 영향)

  • Lee, In-Seok;Kang, Kyoung-Lan;Choue, Ryo-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.5
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    • pp.536-542
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    • 2006
  • High fat diet and chronic alcohol consumption cause hyperlipidemia, steatohepatitis and in some cases, cirrhosis. But the detailed mechanisms are not known. Scutellariae Radix (SR) has been known to have hepatoprotective effects. The aim of this study was, therefore, to determine whether SR water extract (100 mg/kg) could affect immune function in mice abused by long-term alcohol consumption (feed 25% ethanol in water for 1 month, ad libitum) with high fat diet (40% fat of total calorie). Mice received either a regular diet (RD, AIN 93) or a high fat diet (HD); high fat diet group were divided into ethanol group (HED) or ethanol with SR water extract group (HEDS). Food consumption was measured daily and body weights recorded weekly throughout the experiment. Immunological parameters (Ig A, Ig E, TNF-$\alpha$, IFN-$\gamma$, IL-$1{\beta}$) were measured from the serum and the supernatant of spleen lymphocytes from the all groups. The concentration of serum Ig A, Ig E and cytokines were significantly higher in the alcohol consumed groups. Also the concentration of supernatant of spleen lymphocytes, Ig A, Ig E, cytokines were significantly higher in the ethanol consumption groups. Otherwise, HEDS group were significantly lower than HED group. These results suggest that SR water extract may improve the haptic immune function in mice fed high fat diet with alcohol.

Utilization of Wood Chips for Disposing of Swine Manure (목질칩의 축분뇨 정화재로의 이용)

  • Choi, In-Gyu
    • Korean Journal of Environmental Agriculture
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    • v.20 no.4
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    • pp.203-210
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    • 2001
  • In order to environmentally use wood chips manufactured from low valued forest resources by forest tendering, wood chips were used for the evaluation on chips characteristics, decomposition capability of organic wastes, and field experiment and determination of conditions for decomposer. Bioclusters manufactured by Cryptomeria japonica, commercially available wood chips in Japan, showed higher pore ratio, water reservation and water resistance, and higher cellulose content with lower hot water solubles than domestic wood chips. The useful size of wood chips for swine manure decomposition was 10 (length) ${\times}$ 5 (width) ${\times}$ 2 (thickness) mm, and cellulose contents and alkali solubles of Pinus densiflora and Populus tomentiglandulosa were similar to those of bioclusters. According to the decomposition ratio depending on wood species, it was ordered as Pinus densiflora > Pinus koraiensis > Cryptomeria japonica. The swine manure decomposition ratio depending on treatment hours by Pinus koraiensis was constant with the ratio of 15 to 16 g per hour by 1 kg of chip, indicating of daily swine decomposition amount of 390 kg by 1 ton of chips which was equal to the amount of daily swine manure production by 70 swines. Analyzing by long term used wood chips during 40 days treatment, the treated wood chips characteristically showed stable total nitrogen content, suitable pH, high accumulation of inorganic contents such as calcium, phosphorus, potassium and sodium, and no odor. During winter, the inner temperature of decomposer was kept at $43^{\circ}C$, but air bubble was occurred due to high pH and viscosity of swine manure. The most appropriate mixing ratio between wood chips and swine manure was 1 versus 2 or 3, and at more than ratio 1 versus 3, ammonia gas was caused because of anaerobic fermentation status by high moisture content of wood chips. The mixing interval of decomposer was 3 mins. per hour for the best swine decomposition.

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Acute and Chronic Toxicity of Phenol to Mysid, Archaeomysis kokuboi (곤쟁이, Archaeomysis kokuboi에 미치는 phenol의 급성 및 만성독성)

  • KIM Jeong-Seon;CHIN Pyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.1
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    • pp.87-97
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    • 1995
  • Acute and chronic toxicity of phenol on the mortality, long-term survival and respiration rates of the mysid, Archaeomysis kokuboi adult and juvenile were examined. This experiment was condurted by static bioassay procedure with the different salinity at $25^{\circ}C$ In lethal test, the test animals were exposed to 6 different phenol concentrations to determine $LC_{50}$ and I$LT_{50}$ (median lethal concentration and time) values. The $LC_{50}$ values with the exposure time for the mysid adult ranged from 31.31ppm to 1.49ppm phenol and for the mysid juvenile ranged from 6.90ppm to 0.26ppm in all experimental groups. Mortality was increased with the decrease of salinity, The $96hr-LC_{50}$ values at 16, 24 and $32\%o$ salinity for the mysid adult were 1.49, 2.71 and 4.53ppm phenol, white the values for the mysid juvenile were 0.26, 0.56 and 0.71ppm, respectively. The ratios of $96hr-LC_{50}$ values for the mysid adult to those for the mysid juvenile at 16, 24 and $32\%p$ salinity were 5.73, 4.84 and 6.38, respectively. The mysid juveniles were more sensitive to phenol than the mysid adults. Compared $LT_{50}$ values for the mysid adult with those for the mysid juvenile, the $LT_{50}$ values for the mysid adult ranged from 384.7 to 29.0 hours at 1.7-127ppm phenol concentrations and for the mysid juvenile ranged from 132.2 to 18.7 hours at 0.5~6.Oppm phenol concentrations. The lowest $LT_{50}$ values for the mysid adult and juvenile were showed at the combination of the highest experimental concentration of phenol and the lowest experimental salinity. The mysid juveniles showed lower $LT_{50}$ values than those of adults. The chronic effects of phenol on the mysid at the sublethal effective concentration of phenol were lower in the $32\%o$ salinitr group than 16 or $24\%o$ salinity groups. Oxygen consumption rates of the mysid adult were decreased with the increase of phenol concentration and exposure time, and decreased significantly in lower salinity at the same concentration or phenol.

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Effects of Fermented Soybean Extracts and Rain-shelter System on Growth and Disease Occurrence of 'Niitaka' Pear (발효 콩 추출물과 비가림 시설이 '신고' 배나무의 생육과 병해충 발생에 미치는 영향)

  • Lim, Kyeong-Ho;Kim, Byeong-Sam;Kim, Deok-Hyeon;Son, Jang-Hwan;Park, Shin;Cho, Dong-Ho;Jung, Seok-Kyu;Choi, Hyun-Sug
    • Korean Journal of Organic Agriculture
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    • v.24 no.3
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    • pp.557-570
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    • 2016
  • Growth of 6-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees and control of insect and disease occurrences were compared between fermented soybean extracts and rain-shelter system for two years. Foliar application of fermented soybean extracts was applied at 6 times as a pre-experiment in the open-field in 2013, with a rain-shelter system in 2014. Fermented soybean extract treatment increased foliar concentrations of approximately 0.46% T-N, 0.17% K, 0.19% Ca, and 0.06% Mg in 2013 compared to the control, with similar macro-nutrients between the control and soybean extract treatment observed in 2014. Rain-shelter system increased foliar concentrations of T-N, Ca, and Mg compared to the open-field. There were no significantly different between the control and soybean extract treatment for number of leaves per fruit, leaf dry weight, phytotoxicity, and completed shoot growth on August during the two years. Rain-shelter system increased leaf dry weight and did not affect phytotoxicity in the leaves. Fruit quality parameters were mostly similar to control and soybean extract treatment for two years, with higher fruit firmness observed for soybean extract treatment. Rain-shelter system advanced 4 days of harvest dates, and increased approximately 7.0 ton fruit yield per ha, 20 g mean fruit weight, and fruit soluble solid contents compared to open-field in 2014. Soybean extract treatment little suppressed occurrence of disease and insect on the leaves and fruits in both years. Rain-shelter system increased occurrence of Venturia nashicola on the leaves and to 63.8% of Gymnosporangium asiaticum on the fruits in 2014. Strong winds and storms in May elevated relative humidity in the rain-shelter system and caused high infection of the disease occurrence, requiring for an additional green control method. Soybean extract treatment little affected tree growth and would have initiated for a long-term study to evaluate tree physiological characteristics. Rain-shelter system improved fruit productivity and advanced harvest dates, which could have been more effective facility at a Thanks Giving Day between middle and end of September.

Availability of Heavy Metals in Soils with Different Characteristics and Controversial Points for Analytical Methods of Soil Contamination in Korea (토양특성별 중금속 유효도와 토양오염 평가방법의 개선점)

  • Jung, Goo-Bok;Kim, Won-Il;Lee, Jong-Sik;Shin, Joung-Du;Kim, Jin-Ho;Yun, Sun-Gang
    • Korean Journal of Environmental Agriculture
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    • v.24 no.2
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    • pp.106-116
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    • 2005
  • This experiment was conducted to investigate available extraction capacity and potential mobility of heavy metal according to the distribution property and contamination level of heavy metals in soils and to suggest a reform measure of soil environment assessment methodology applied with soil quality and the official soil heavy metal test methods in domestic and foreign countries. The soils were collected from the natural forest paddy with long-term application of same type fertilizer, and paddies near metal mine and industrial complex. The post-treatment methods of soil were partial extraction, acid digestion and sequential extraction methods. For the heavy metal contents with different soil properties, it was shown that their natural forest and paddy soil were slightly low and similar to the general paddy soil, while their paddies near metal mine and industrial complex were higher than the standard level of Soil Environment Protection Act. Heavy metal concentrations in the soils with different soil properties had difference between $HNO_3\;and\;HNO_3+HCl$ extractant by US-EPA 3051a method. There were highly significant positive relationships in both two methods. It was appeared that the higher extractable concentration ratio with 0.1N-HCl to total heavy metal content with $HNO_3+HCl$ extractant the greater total heavy metal content. There were highly significant positive correlationship between total heavy metal content and extractable content with 0.1N-HCl. For extractable capacity of soil extractable solution compared to the total heavy metal content it was appeared that it extractable method with 0.1N-HCl was higher than those with EDTA and DTPA. In extractable ratio with 0.1N-HCl in the contaminated paddy soils near mine and industrial complex, it was shown that the lower soil pH, the higher total heavy metal content. The order of a potential mobility coefficient by distribution of heavy metal content with ie different typies in the soil was Cd>Ni>Zn>Cu>Pb. It could be known that contamination characteristics of heavy metals with different types of soils were affected by different heavy metal components, contamination degree and soil chemical properties, and heavy metal concentration with different extractable methods had great variations with adjacent environment. To be compared with assessment methodology of soil environment impact at domestic and foreign countries with our results, it might be considered that there was necessary to make a single analysis method based on total heavy metal content with environmental overloading concept because of various analysis methods for total heavy metal content and present analysis method with great variation according to soil environment. In spite of showing higher concentration of heavy metal with acidic digestion than the extractable method, it might be considered that there is need to be adjusted the national standard of soil heavy metal contamination.