• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.32-39
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• 1999

The following is experimental result of selecting soil bacteria showing toxicity against Root-knot nematode (Meloidogyne hapla). Out of 286 strains isolated from soil, one(NC67) showing toxicity against M.hapla is selected The selected strain(NC67) is identified of B. thuringiensis subsp. indiana. It proved out that the toxic maerial against M. hapla produce by NC67 strain is an exotoxin. The result of examining the existence of the extercellular toxicity product by the toxic strain(NC67) by usign activated carbon column chromatography, Dowex 50W column chromatography and TLC of silical gel etc. proved out that it is a single material.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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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.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.373-377
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• 1995

Four Bacillus thuringiensis isolates obtained from soil samples in Korea produce parasporal inclusions non-toxic to 10 insect species of three orders, Lepidopera, Diptera and Coleoptera. These four isolates are named NTB-1, NTB-2, NTB-3 and NTB-4, respectively. The morphology of parasporal inclusions of four isolates observed by phase contrast- and scanning electron microscope was all ovoid. Characterization of four non-toxic B. thuringiensis isolates was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and restriction endonuclease analysis. The results showed that parasporal inclusion proteins and total plasmid DNA profiles of four isolates are different from other known non-toxic B. thuringiensis strains', suggesting that four isolates are novel.

• Journal of Soil and Groundwater Environment
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• v.22 no.5
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• pp.82-88
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• 2017

Contaminated sediment can be treated in order to reuse the treated sediment. Even though the chemical criteria are satisfied, the treated sediment could still impose toxic effects. Therefore, this study investigated the changes in the ecological toxic effects of the contaminated sediment from the J region in Singapore after treatment. The contaminated sediment was subject to sequential soil washing and thermal treatment, followed by pH neutralization. Toxic effects of the contaminated and treated sediments were determined by using Vibrio fischeri ($Microtox^{(R)}$), Triticum aestivum (wheat), and Eisenia foetida (earthworm). After treatment, the concentrations of total petroleum hydrocarbons and heavy metals were decreased by 98% and 59-93%, respectively, and satisfied the Industrial Maximum Values of the Dutch Standard, which were used as the remedial goal. The bioluminescence reduction of V. fischeri decreased significantly, and the earthworm survival increased from 0% to 90% after treatment. The germination rate increased from $0{\pm}0%$ to $75{\pm}13%$ after treatment, but the treated sediment may need additional treatment such as nutrient addition for better plant growth. Overall, this study showed that the treatment of the contaminated sediment satisfactorily removed mixed contaminants, and this led to reduction in toxic effects, suggesting improved potentials for reuse of the treated sediment.

• Journal of Soil and Groundwater Environment
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• v.23 no.1
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• pp.63-73
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• 2018

Rice is a staple food source in Asian countries. In paddy field, rice plant can take up toxic elements through its roots from contaminated soils, and its leaves and grain can absorb the toxic elements deposited on the soil surface. A totla of 40 soil and polished rice samples were collected around four abandoned metal mines in Korea and analyzed for As, Cd, Cu, Pb and Zn by atomic absorption spectrophotometer (AAS). The average contents of As, Cd, Cu, Pb and Zn in rice grain grown on the contaminated soils were 0.247, 0.174, 4.694, 0.804 and 16.78 mg/kg, respectively. These levels are higher than worldwide average concentrations. Assuming the rice consumption of 169 g/day by overall households in Korea, the estimated daily intakes from the rices were found to be 33, 48, and 63% for As, Cd, and Pb, respectively, of the acceptable daily intake (ADI) suggested by the FAO/WHO Joint Food Additive and Contaminants Committee.

• Korean Journal of Environmental Biology
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• v.29 no.3
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• pp.208-211
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• 2011

The lowest amount of heavy metals was found outside the city (25 km away), the highest amount was found near the thermoelectric power plant, and the average amount was discovered in the central part of the city. The presence of heavy metals in soil samples resulted in reduction of several important soil characteristics (pH, humus content, soil "breathing"). Use of simple and quick methods to examine soil with high heavy metals pollution resulted in the discovery of a pedobiota group, consisting of nematodes, fungi (genus Fusarium) and Protozoa which indicated the toxicity of the Almaty city soils.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.252-254
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• 2004

In the past several years phytoremediation, defined as the use of plants for removing contaminants from media such as soils or water, has attracted a great deal of interest as a potentially useful remediation technology. In this study, we have attempted to asses the effectiveness of phytoremeidation of disel contaminate soils using hybrid poplar species. 3 poplar species had removed disel from soil effectively and toxic effect was also observed over 2500mg/kg disel contaminated soil, which indicating reducing disel removal.

• Economic and Environmental Geology
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• v.31 no.6
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• pp.509-518
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• 1998

Fly ashes have been deposited around Youngwol power plant until electrostatic precipitator was installed in 1981. Fresh fly ash samples from electrostatic precipitator and weathered fly ash from ash disposal site were collected from Youngwol power plant, along with 65 soil samples of nearby area to look into the influence of PFA deposit on the soils in surrounding area. In chemistry, EPA does not contain high level of toxic elements and there is no notable concentration of toxic elements in soil near power plant. Total concentrations of Co, Cr, Cu, V, and Zn are 13 ppm, 89 ppm, 73 ppm, 157 ppm and 57 ppm in PFA. Concentrations of theses elements in ash-rich soils are 15 ppm, 78 ppm, 60 ppm, 133 ppm and 68 ppm, and those in ash-poor soils are 19 ppm, 70 ppm, 38 ppm, 91 ppm and 97 ppm. But these metal elements are highly concentrated in magnetic fractions of EPA (Co, 129 ppm; Cr, 217 ppm; Cu, 210 ppm; V, 197 ppm; Zn 90 ppm). Considering the process of long-term weathering of PFA, potentially toxic substances from the ash could be leached into soils and groundwater.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.318-322
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• 2004

Arsenic is a toxic and carcinogenic metalloid, whose sources in nature include mineral dissolution and volcanic eruption. Abandoned mines and hazardous waste disposal sites are another major source of arsenic contamination of soil and aquatic systems. To predict concentrations of the toxic inorganic arsenic in aqueous phase. the biogeochemical redox processes and transport behavior need to be studied together and be coupled in a reactive transport model. A new reaction module describing the fate and transport of inorganic arsenic species (As(II)), dissolved oxygen, nitrate, ferrous iron, sulfate, and dissolved organic carbon are developed and incorporated into the RT3D code.

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.12-17
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• 2013

Heavy metal contamination of soil and water from industrial sources remains a worldwide environmental concern. Concentrations of toxic metals were measured in soil from banks of the Han and Anyang rivers. Pre-monsoon samples contained the highest heavy metal concentrations (Cu > As > Pb > Cd > $Cr^{6+}$; up to 57.80, 38.23, 25.43, 2.21, 0.32 mg/kg, respectively), but concentrations decreased at all sites during the monsoon and post-monsoon seasons. Higher heavy metal concentrations in pre-monsoon samples may be attributed to dust pollution, especially from roads near the river. A gradual reduction in heavy metal concentrations during the rainy season may be due to washing out. The high concentration of metals could cause health problems, especially in residential areas.