• Applied Biological Chemistry
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• v.22 no.4
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• pp.221-226
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• 1979

The soils and plants were sampled from 26 sites of Deogpyeongri, Goisangun, which had been found to be one of the uranium deposit areas. Uranium levels of the samples were determined and the amount of uranium intake by the residents through the food-chains was estimated. The average uranium concentration of Deogpyeongri soils was 15.5ppm with a range of from 4.9 to 43.6ppm showing rather higher values than those of control area, Yangjugun and Icheongun, Gyeonggi-do. The average uranium content of the plant samples from Deogpyeongri was 0.69ppm, about twice the uranium concentration of the control samples. The daily intake of uranium by an adult lived on the agricultural food stuffs produced in Deogpyeongri, was estimated to be about $247{\mu}g$, eqivalent to $0.83{\times}10^{-4}{\mu}Ci$, which is much higher activity compared to the daily intake of uranium by New York citizen, $1.3{\mu}g$. However the calculated uranium level accumulated in the human body of Deogpyeong area was $2.03{\times}10^{-4}{\mu}Ci$ which is still lower than $0.2{\mu}Ci$, the maximum permissible burden in total body recommended by the ICRP.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.114-117
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• 2007

The effects of faecally excreted ivermectin on the survival and growth of the common Korea earthworm Eisenia fetida (Savigny), have been studied in the laboratory. Cow dung was collected 1, 2, 3 and 7 days after ivermectin subcutaneous injection. The mortality of the worms provided with untreated dung was 0% whereas mortality within a week was high as 73.7%, 98.3% in dung which were excreted 1 and 2 days from dosing, respectively. The growth rate of the worms fed dung from 1 day excreted dung from cattle given ivermectin was 75% lower than that recorded on the control. In total number of hatchling earthworm in each treatment, 1 day after treatment produced the lowest compared with untreated control. However, dung from cattle treated with ivermectin did not prevented the rate of hatchling from each cocoon of earthworm. The results show that ivermectin is less toxic to $2^{nd}$ generation of earthworm. We concluded that ivermectin have adverse effects on the survival and growth of E. fetida when exposed through dung under laboratory conditions. This results will be discussed in relation to the effects of anthelmintics on non-target organism in our ecosystem.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.391-395
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• 2018

There is an increasing concern over arsenic (As) contamination of paddy soil and rice with regard to food safety. This study was conducted to investigate total and inorganic As concentration in one hundred husked and polished rice samples collected at the non-contaminated paddy soil in Korea. Arsenic species in rice samples were extracted using 1% nitric acid ($HNO_3$) with a microwave oven and were measured using high performance liquid chromatography coupled with inductively coupled plasma-mass spectrometry. Mean concentrations of total As in husked rice and polished rice were 0.18 and $0.11mg\;kg^{-1}$, respectively. Also, average inorganic As concentrations in husked rice and polished rice were 0.11 and $0.07mg\;kg^{-1}$, respectively. These levels are lower than the standard guideline value 0.35 and $0.2mg\;kg^{-1}$ for inorganic As in husked and polished rice recommended by Codex Committee on Contaminants in Foods and Ministry of Food and Drug Safety, respectively. The mean of the inorganic As ratio for the total amount of As was 0.65 and 0.67 for husked rice and polished rice, respectively, and the range was from 0.08 to 1.0. For health risk assessment, the average value of cancer risk probability was $9.24{\times}10^{-5}$ and ranged from $2.30{\times}10^{-5}$ to $1.90{\times}10^{-5}$. Therefore, human exposure to As through dietary intake of surveyed rice samples might considered to be a low health risk.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.127-134
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• 2010

A study was conducted to determine the effects the of cattle manure application on forage yield, quality and soil in orchard grass pasture at the experimental field of Subtropical Animal Experiment Station, National Institute of Animal Science from 2008 to 2009. The experiment was arranged in a randomized complete block design with three replications. The treatment consisted of chemical fertilizer (CF N-200 kg/ha), cattle manure 50% (basis N, CM50%), CM100% (basis N), CM200% (basis N). The dry matter (DM) yield of CM200% was the highest among the other treatments. CF showed the highest average crude protein (CP) content by 12.4% and CM50% showed the lowest content by 11.0%. Average acid detergent fiber (ADF) and neutral detergent fiber (NDF) content were 30.4 and 69.7% respectively. All treatments have narrow range of total digestibility nutrient (TDN) from 64.0% to 69.1%. But there were big difference between treatment in forage nitrate content. Changes of physical and chemical properties of soils for applications of CF 200% and CM 200% was clearly in cattle manure application. Especially, CM application in pasture increased CF application with respect to soil pH, organic matter (OM), and avaliable phosphorous ($P_2O_5$) contents of soils.

• Journal of Mushroom
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• v.15 no.4
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• pp.183-189
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• 2017

This study investigated the synergistic effect of single inoculation and co-inoculation of phosphate-solubilizing bacteria (PSB) Burkholderia metallica JH-7 and Burkholderia contaminans JH-15. Phosphate-solubilizing abilities of these strains were assessed by measuring phosphorus content in culture media that were singly inoculated or co-inoculated with these strains for 7 days. B. metallica JH-7 was found to release the highest content of soluble phosphorus ($140.80{\mu}g\;mL^{-1}$ ) into the medium, followed by single inoculation of B. contaminans JH-15 ($135.95{\mu}g\;mL^{-1}$ ) and co-inoculation of two strains ($134.84{\mu}g\;mL^{-1}$ ). The highest pH reduction, organic acid production, and glucose consumption were observed in the medium inoculated with B. metallica JH-7 alone compared with that in the medium co-inoculated with both the strains. Results of a plant growth promotion bioassay showed 17.4% and 7.48% higher leaf and root growth, respectively, in romaine lettuce inoculated with B. metallica JH-7 alone than in romaine lettuce inoculated with a control strain. However, no significant difference was observed between single inoculation and co-inoculation of these strains with respect to phosphorus release and plant growth. Although the results of the present study did not show the synergistic effect of phosphate solubilization by the PSB strains examined, these results indicate that treatment with PSB exerts a beneficial effect on crop growth.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.69-75
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• 2006

Improper disposal of petroleum and spills from underground storage tanks have created large areas with highly toxic contamination of the soil and groundwater. Methyl tert-butyl ether (MTBE) is widely used as a fuel additive because of its advantageous properties of increasing the octane value and reducing carbon monoxide and hydrocarbon exhausts. However, MTBE is categorized as a possible human carcinogen. This research investigated the Modified Photo-Fenton system which is based on the Modified Fenton reaction and UV light irradiation. The Modified Fenton reaction is effective for MTBE degradation near a neutral pH, using the ferric ion complex composed of a ferric ion and environmentally friendly organic chelating agents. This research was intended to treat high concentrations of MTBE; thus, 1,000 mg/L MTBE was chosen. The objectives of this research are to find the optimal reaction conditions and to elucidate the kinetic and mechanism of MTBE degradation by the Modified Photo-Fenton reaction. Based on the results of experiments, citrate was chosen among eight chelating agents as the candidate for the Modified Photo-Fenton reaction because it has a relatively higher final pH and MTBE removal efficiency than the others, and it has a relatively low toxicity and is rapidly biodegradable. MTBE degradation was found to follow pseudo-first-order kinetics. Under the optimum conditions, [$Fe^{3+}$] : [Citrate] = 1 mM: 4 mM, 3% $H_2O_2$, 17.4 kWh/L UV dose, and initial pH 6.0, the 1000 ppm MTBE was degraded by 86.75% within 6 hours and 99.99% within 16 hours. The final pH value was 6.02. The degradation mechanism of MTBE by the Modified Photo-Fenton Reaction included two diverse pathways and tert-butyl formate (TBF) was identified to be the major degradation intermediate. Attributed to the high solubility, stability, and reactivity of the ferric-citrate complexes in the near neutral condition, this Modified Photo-Fenton reaction is a promising treatment process for high concentrations of MTBE under or near a neutral pH.

• Journal of Animal Environmental Science
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• v.1 no.2
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• pp.117-124
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• 1995

This study was carried out to investigate the effect of depth of sawdust bedding and ground material in dairy cattle barn. Treatment included the concrete floor with a 10cm or 30cm sawdust and the earth floor with a 30cm sawdust. Eighteen cows were assigned to 3 pens with 16.5㎥/head bedding area. The results obtained were as follows : 1. The temperature of sawdust bed was highest in the earth floor with 30cm sawdust, and the moisture content of sawdust bed was highest in the concrete floor with 10cm sawdust bed. 2. Cows defecate feces 9.2, 8.7 and 9.3 times a day in 10cm sawdust on concrete floor(10S+C), 30cm sawdust on concrete floor(30S+C) and 30cm sawdust on non concrete floor(30S+ NC) respectively. In average, they excreta 9.1 times/day(85.8%) in the sawdust beds and 1.5 times/day(14.2%) in the feeding alley. 3. The ratio of daily water amount deposited vapor to total water amount deposited in sawdust beds was 74.0%, 61.5% and 47.1% in 10S+C, 30S+C and 30S+NC respectively. 4. N.P.K contents in the sawdust beds were higher for 10S+C compared with other treatments. 5. When 30cm of sawdust was applied on the earth ground NO$_3$-N contents in the sawdust bed was 37.7, 14.1 and 15.0ppm in depth of 30, 60 and 90cm under the ground, respectively, indicating some possibility of water pollution.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.14-21
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• 2015

To determine residual characteristics of azoxystrobin in ginseng under different cultivation conditions such as use of straw mat on cultivation soil and filling gap between ginseng stem and soil surface and also to elucidate its approximate behavior after spraying, 20% azoxystrobin suspension concentrate solution was sprayed 4 times onto 5-year-old ginseng with 10 days interval at a application rate of about 200 L/10 a and then residues in samples were analyzed. The residue level was lower in case of use of straw mat and filling the gap with soil than in case of no use of straw mat and no filling the gap, representing that use of straw mat and filling the gap with soil were contributed to decrease of pesticide residues in ginseng. A large portion of the test pesticide distributed onto ginseng leaf with a higher specific surface area. The amounts of azoxystrobin residues decreased in ginseng leaf, while increased on soil surface, as close to harvest. About 0.1% of azoxystrobin sprayed was distributed in ginseng root and 12.7-20.4% (mean 16.6%) of azoxystrobin could be decreased for dietary intake by removing of rhizome from ginseng root before intake.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.335-343
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• 2003

An experiment was conducted to investigate types of injury inflicted by the stone leek leafminer, Liriomyza chinensis Kato (Diptera: Agromyzidae) on welsh onion. A feeding scar made by an adult female was a hole round in shape, with diameter of 0.08 mm and 0.48 mm in lesion, resulting in a white spot, many of which often form vertical dotted lines on a leaf. Egg spots were oval with 0.1 ${\times}$0.14 mm in size, one or several of which often form a V-shape in group. Feeding by adults began immediately after emergence and was very active from 4th to 5th day. Oviposition was done from 2nd to 6th day after emergence. In both feeding and oviposition, they were more active in the day time. Larvae after emergence crawled up the leaf at first, and then moved up and down to feed on mesophyll. When in high density, they feed on leaf from leaf tip to bottom, and let the leaf die. Area of damage per one larva was calculated as 72.1 $\textrm{mm}^2$. The aged larvae escaped from the leaf in early morning, usually between 5 and 7 am. Most pupation sites were distributed near plants,5cm in soil depth and within 10 cm away from the plant. Pupae of L. chinensis overwintered 10cm below soil surface and emerged from early May to late June the next year Adults then moved to welsh onions near over wintering sites, nursery, transplanted, and levee.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.779-784
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• 2003

Nitrate a common component of man's chemical environment, is present in foods either naturally or in an additive introduced during processing of foods. Nitrate level of foods have been found depending on nitrosation of soils and other various environmental factors. Therefore data on nitrate contents of foods reported in other countries can not be adapted to Korean foods. Also data on nitrate levels of Korean foods available were reported 10 years ago, which would be assumed to differ from those of foods currently consuming by Koreans. The present study was attempted to determine nitrate contEnts of common foods. Based on National Nutrition Survey Report 143 food items out of 14 food groups were selected for this study Nitrate levels of common foods used in the study were from N.D (not detected) to 6733.33 mg/kg foods. Mean nitrate levels of food groups 27.2 mg/kg of cereal and grain products, 78.1 mg/kg in potatoes and potato products, 8.3 mg/kg in legumes and their products N.D of seeds and nuts, 1012.1 mg/kg of vegetables and their products,76.3 mg/kg fungi and mushrooms 42.2 mg/kg fruits,34.5 mg/kg of meat, poultry and their products,0 mg/kg in eggs, 23.9 mg/kg in fish, shellfishes and their products,23.0 mg/kg in seaweeds, 7.7 mg/kg milk and dairy products, 26.3 mg/kg in seasonings, 68.0 mg/kg in others.