• Korean journal of applied entomology
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• v.44 no.2
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• pp.97-108
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• 2005

Samples of water, soil, and sediment were taken from 10 streams near Andong, Korea in May 2004. To assess the degree of environmental pollution of each stream, chemical pollutants such as total notrogen (T-N), total phosphorus (T-P), chemical oxygen demand (COD), heavy metals, organophosphorus pesticides, organochlorine pesticides, and dioxin-like PCB congeners were analyzed by standard process tests or U.S. EPA methods. In addition, biomarkers originated from insect immune systems of beet armyworm, Spodoptera exigua, were used to analysis of the environmental samples. Except Waya-chun stream showing T-N content of 9.12 mg/L, most streams were contaminated with relatively low levels of overall pollutants in terms of T-N, T-P, and COD, compared to their acceptable environmental levels designated by the Ministry of Environment. Contents of Pb and Cd in samples of each stream were much lower than environmentally permissible levels. However, several times higherconcentrations of Pb and Cd were found in locations at Mi-chun, Kilan-chun, and Hyunha-chun streams, in comparison with other streams. Diazinon, parathion, and phenthoate compounds among organophosphorus pesticides were detected as concentrations of 0.19, 0.40, and $1.13\;{\mu}g/g$, respectively, from soil sample collected in the vicinity of Mi-chun stream. On the other hand, 16 organochlorine pesticides and 12 dioxin-like PCB congeners, known as endocrine disrupting chemicals, selected in this study were not found above the limit of detection. Biomarker analyses using insect immune responses indicated that Waya-chun stream was suspected as exposure to environmental pollutants. Limitation and compensation of both environmental analysis techniques are discussed.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.7-17
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• 1972

Samples of 13 vegetables were collected, between 14 July and 6 August, 1971, from 15 markets located in 12 different cities and analyzed for Heptachlor residues by gas liquid chromatograph. The residue concentrations of Heptachlor and its epoxide were estimated separately, at a sensitivity level of 0.001 p.p.m., to produce Heptachlor residues on the fresh weight basis. The Heptachlor residues in or on the crops analyzed, including three staple vegetables, potatoe, radish and chinese cabbage, were found fairly low and are far lower than the residue tolerences for respective vegetables recommended jointly by FAO and WHO of the United Nations.

• Applied Biological Chemistry
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• v.17 no.3
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• pp.177-183
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• 1974

One hundred and twenty-five samples comprising thirteen vegetables harvested in 1971 were collected and subjected to GLC analysis, for ${\alpha}-and\;{\gamma}-BHC$ residues, using ECD. Heavy dependence on the technical BHC, instead of Lindane, was amply reflected on the BHC residues-residues of ${\alpha}-BHC$, depending on the vegetables, amounted to $2{\sim}7$ times that of ${\gamma}-BHC$. In spite of extensive contamination by the BHC isomers, residue levels of ${\gamma}-BHC$ were less than 0.015 ppm in all vegetables and were far less than the tolerence limit of $0{\sim}3.0ppm$ recommended jointly by the FAO and WHO.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.299-306
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• 1984

The influences of applications of organochlorine insecticide (HCH: Hexachlorocyclohexane, 10 ppm), fungicide (TPN: Tetrachloroisophthalonitrile, 40 ppm) and manure ($3Kg/m^2$) each or together on changes in soil microflora for consecutive years were investigated in the experimental field plots. The insecticide had a little effect on soil microbial numbers. In particular, the number of total bacteria, Gram-negative bacteria and fungi were gradually increased at the latter stage of the consecutive application, but the number of sporeforming bacteria reduced. The fungicide reduced the counts of sporeforming bacteria, actinomycetes and fungi respectively, whereas increased prominently the counts of total bacteria and Gram-negative bacteria. TPN-resistant bacteria, particulary TPN-resistant Gram-negative bacteria were gradually accumulated by the long-term application of TPN, and further the number of TPN-resistant total bacteria and the of TPN-resistant Gram-negative bacteria correlated fairly well during all the period. The influences of combined applications of both HCH and TPN on the number of soil microorganisms were equal to the respective sums of the effects of single application of each pesticide. The combined application of manure and these pesticides elevated the increasing extents of microbial numbers, while weakened the detrimental efforts of these pesticides on microbial numbers. These data suggest that the long-term application of these materials have resulted in the remarkable changes of composition of soil microflora.

• Journal of Life Science
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• v.32 no.10
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• pp.771-777
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• 2022

Dopaminergic (DA) cell death in Parkinson's disease (PD) has been attributed to multiple, distinct genetic and environmental factors. In rare familial PD loss of parkin function mutations play a key role in nigral DA neuron-specific pathogenesis primarily via endoplasmic reticulum (ER) stress. In more prevalent sporadic PD, environmental exposure to pesticides has a significant epidemiological role. However, it is largely unknown how environmental exposure to xenobiotics is etiologically linked with the known etiology in familial PD. In the present study biochemical evidence for a common pathogenic mechanism between sporadic and familial PD has been identified employing the recently characterized mesencephalic DA cell line, N27-A. Dieldrin, an organochlorine pesticide epidemiologically implicated in sporadic PD, induced the markers of ER stress response such as a chaperone BiP/Grp78, heme oxygenase-1 and especially, parkin. Accordingly, dieldrin activated the ER resident Caspase-12, a mediator of ER stress-specific apoptosis, during cell death of N27-A cells. Of great interest the dieldrin-induced DA neuronal cell death was synergistically rescued by the overexpression of ER resident neuroprotective proteins, parkin and Bcl-2. The present findings implicate that accumulation of ER stress could be one of common pathogenic mechanisms in idiopathic and familial PD, and some ER proteins, such as parkin and Bcl-2 may effectively attenuate ER stress-mediated N27-A DA cell death.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.210-214
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• 2003

Pesticide residues in some vegetables collected at Noeun wholesale market in Daejeon were surveyed and assessed their risk. In 100 samples, the detection rate of pesticide was 46.0% and the rate exceed MRL was 6.0%. Commodities showing high detection rate were lettuce(85.0%), perilla leaf(80.0%) and cucumber(60.0%). Dicarboximide, organochlorine, and azole fungicides and organophosphorus and pyrethroid insecticides were detected. Detection frequency of pesticide was in the order of procymidone, chlorpyrifos, chlorothalonil, cypermethrin and EPN. When the estimated intake amount of the pesticides were compared with ADI to assess their risk, bitertanol, triflumizole and iprobenphos in perilla leaf were higher rate than the other vegetables. However the total amounts of intake of pesticides were estimated to less than 0.46% of ADI.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.306-312
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• 1978

Residue levels of an organochlorine insecticide, BHC, were determined for brown rice samples produced in Korea by collection and field experiments to obtain the following results. 1) Residue levels of total BHC in 112 samples (an Indica type variety Tongil) produced in 1976 and collected from 9 provinces in proportion to the production level of rice ranged from 0.0010 to 0.0762 ppm, the average being 0.0061 ppm. 2) The residue levels in samples from Jeonbook, Kyongnam and Choongnam provinces were higher than the average for whole samples. BHC isomers were found in the order of ${\alpha}>{\gamma}>{\beta}>{\delta}$ isomers, and the detection frequency by range were 89.3% below 0.01 ppm, 9.8% for $0.01{\sim}0.05{\;}ppm$ and 0.9% for $0.05{\sim}0.10{\;}ppm$. 3) In field experiments according to conventional agronomical practices, the brown rice samples after spraying of BHC at the first generation time of rice stem borer (4 kg of 6% granular formulation/10 a paddy field) showed a little higher residue level than control samples, but not more than 0.035 ppm, whereas samples after spraying at the second generation time (3 kg/10 a) contained in the range of $0.04{\sim}0.19\;ppm$.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.25-32
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• 1970

This experiment was conducted to find out the simultaneous control effect of granulated insecticides on the several major rice insect pests in Korea. The granulated insecticides used were Terracur P$5\%$ (one of the phosphoric insecticides), Lebaycid $5\%$, and Sang-gamma (gamma-BHC) $6\%$. Those insecticides were broadcasted by hand on the paddy field at the ratio of 3kg. in June and 4kg. in August per 10 a, and the date of insecticidal application was based on the maximum moth occurrence of the rice stem borer in 1969. The rice insect pests tested in this study were rice stem borer (Chilo suppressalis W.), green rice leafhopper (Nephotettix bipunctatus cincticeps U.), smiller brown planthopper (Laodelphax striatellus F.), and white back planthopper (Sogotella furcifera H.). For the study of residual effectiveness of the insecticides, the rice stem borer larvae just hatched from the eggs were installed on the sheath of rice plants collected from the paddy field after insecticidal treatment, and the mortality was made at 48 hours after installation. High mortality was observed in Terracur P and Sang-gamma treatments and low mortality in Lebaycid treatment. The duration of residual effects giving about 50% mortality was about 14 days in Sang-gamma and about 6 days in Terracur P treatments. The study on the effectiveness of the insecticides to the rice stem borer in the paddy field was made by the number of dead blades and white heads of the rice plants injured by the larvae, and the number of survival larvae in the straws after crop harvest. The order of insecticidal effectiveness to the rice stem borer was Terracur P=Sang-gamm>Lebaycid. The study on the effectiveness of the insecticides to the leafhoppers and planthoppers in the paddy field was made by the population density by sweeping (5 times) at the given day intervals after treatments. Terracur P was highly effective for the control of the green rice leafhoppers and Lebaycid was moderately effective, but Sang-gamma seemed not to be effective. The effectiveness of the insecticides tested to the planthoppers was not clear, and it seemed to related with the low insect population density. Study on the determination of proper timing of insecticidal application was not also made clear, and it seemed to be short in the range of day intervals in the insecticidal application. For the study on the control effects of the rice insect pests, rice yield per 100 hills per plot was observed. There was no statistically significant difference among the treatments in rice yields, but the order of yield (Terracur P>Sang-gamma>Lebaycid>Control) was paralleled with the tends of control effects above mentioned. In a view point of simultaneous control of the rice stem borers and green rice leafhoppers by the application of granulated insecticides, Terracur P and Lebaycid were more effective than Sang-gamma which have been used.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.114-121
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• 2007

The purpose of this study was to investigate 253 kinds of pesticide residues in 58 commercial dried agricultural products in Seoul. The determinations of the pesticide residues were performed using multiresidue methods and were carried out by a gas chromatography-nitrogen phosphorus detector (GC-NPD), an electron capture detector ($GC-{\mu}ECD$), a mass spectrometry detector (GC-MSD) and high performance liquid chromatography-ultraviolet detector (HPLC-UV), and a fluorescence detector (HPLC-FLD). The pesticide residue detection rate in the commercial dried agricultural products was 24.1% (14 of 58 samples). Twelve pesticide residues without maximum residue limits (MRLs) were detected. In the vegetable groups, the frequency of pesticide residues was found to be in the increasing order of dried fruiting vegetables > dried leafy vegetables > dried stalk and stem vegetables. The pesticides used on dried red pepper in the dried fruiting vegetables were varied (7 kinds) and numerous (4 of 8 samples). The pesticide types detected in the commercial dried agricultural products were in the order of pyrethroid > organochloride > organophosphorus and insecticide > fungicide > herbicide ${\cdot}$ nematicide. The primary pyrethroid pesticide detected was cypermethrin. According to the producing areas of products, large numbers of pesticide residues were found in the order of Korea, China, North Korea, USA, and Vietnam.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.8-13
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• 1988

This experiment was conducted to evaluate the effect of polyethylene film(P.E.) mulching on degradation of the soil insecticides, endosulfan(6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), fonofos(O-ethyl S-phenyl ethylphosphonodithioate), and ethorprophos(O-ethyl S, S-dipropyl phosphorodithioate) in red pepper, peanut, and sesame fields. Degradation of endosulfan, fonofos and ethoprophos in the soils under P.E. mulching and non-mulching followed first-order kinetics. The half-lives of fonofos, ethoprophos, ${\alpha}-$ and ${\beta}-endosulfan$ were $19{\sim}21$, $25{\sim}37$, $33{\sim}39$ and $56{\sim}81$ days, respectively. There were few differences in the half-lives of fonofos in either mulching or non-mulching concitions. However, half-lives of α-endosulfan, ethoprophos, and ${\beta}-endosulfan$ were 6, 12 and 25 days longer under P.E. mulching than under non-mulching conditions, respectively. The effect of P.E. mulching on degradation was remarkable for the slower degrading insecticides. Residues of ethoprophos in the harvested sesame under P.E. mulching and non-mulching conditions were 0.024 and 0.074ppm, respectively. Residues of fonofos in the harvested peanuts under P.E. mulching and non-mulching conditions were 0.078 and 0.017ppm, respectively. However, no endosulfan was detected in the harvested red peppers under either condition.