• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.357-366
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• 2011

BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.

• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.902-909
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• 1995

Detection limit as well as calibration curves on organophosphorus pesticide(dimethoate, diazinon, parathion-methyl, fenitrothion, malathion) and BHCs were measured for evaluation of utility on qualitative or quantitative analysis of pesticides with ion Trap mass spectrometer and quadrupole mass spectrometer. As ionization source, EI and CI were adopted for qualitative analysis of pesticides by comparison of each fragmentation pattern. At the same time, the utility as trace analysis techniques through scan or selected ion monitoring(SIM) mode was evaluated. With ion trap for all pesticides, detection limit(DL, 1 ${\mu}L$ injection) on scan mode was ranged 0.008∼0.225 ng at signal to noise ratio 3. With quadrupole DL on scan mode was ranged 0.23∼3.1 ng over 0.032∼0.68 ng on SIM mode. The calibration curve with ion trap generated good linearity over 0.99 as correlation coefficient. As clean up procedure, Bio Beads S-X3 was used for the separation of oils from five organophosphorous pesticides in flour extractant showing more than 80% as recovery at most cases. In case of BHCs in jinseng with Florisil column, the recovery of pesticides has been 60% to 90%.

• KSBB Journal
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• v.24 no.3
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• pp.227-238
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• 2009

In the recent years, some organic toxic chemicals were used for obtaining high-yield productivity in agriculture. The undegraded pesticides may remain in the agricultural foods through atmosphere, water, and soil and cause public health problems to environmental resources and human beings even at very low concentrations. Small amounts of pesticides can affect a central nervous system, resulting in immunogenic diseases, infertility problems, respiratory diseases and born marrow diseases, which can lead even to death. Monitoring of the environmental pesticide is one of the important issues for the human well-being. Several kinds of biosensors have been successfully applied to the detection of agrichemical toxicity. Also, few platforms for biocide detection have been definitely developed for the degradation and reaction of pesticides. Biochip and electrochemistry experiments involve immobilizing a receptor molecule on a solid substrate surface, and monitoring its interaction with an analyze in a sample solution. Furthermore, nanotechnology can be applied to make high-throughput analyses that are smaller, faster and sensitive than conventional assays. Some nanomaterials or nanofabricated surfaces can be coupled to biomolecules and used in antibody-based assays and enzymatic methods for pesticide residues. The operation procedure has become more convenient as it does not require labeling procedure. In this paper, we review the recent advances in agrichemical defection research and also describe the label-free biosensor for pesticides using various useful detection methods.

• Korean Journal of Environmental Agriculture
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• v.41 no.2
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• pp.108-114
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• 2022

BACKGROUND: This study was performed to determine residual characteristics of soil-treated metalaxyl-M and dinotefuran in crown daisy and to evaluate the risks from intake of the residual pesticides in the crop. METHODS AND RESULTS: The pesticide granules were treated in soil on two levels, and the plants samples were collected 51 days after seeding. The analytes were extracted and partitioned using the QuEChERS extraction packet (MgSO₄ 4 g, NaCl 1 g). The quantitative methods for metalaxyl-M and dinotefuran were validated in linearity, accuracy, and precision. Risk assessments of the pesticides were performed using Korea national nutrition statistics 2019. CONCLUSION(S): The residual concentrations of metalaxyl-M in crown daisy were 0.09-0.10 mg/kg (for the treatment at 6 kg/10 a) and 0.17-0.19 mg/kg (12 kg/10 a), respectively. The residual concentrations of dinotefuran in the crop were 0.53-0.75 mg/kg (3 kg/10 a) and 1.17-1.26 mg/kg (6 kg/10 a). The amounts of pesticides were less than MRL (Maximum Residue Limits) according to the Korean MFDS (Ministry of Food and Drug Safety). The HI (Hazard Index) of metalaxyl-M and dinotefuran for consumers was 0.0075% and 0.2250%, respectively. For females in the age between 50-64, the major consumer group, the HIs of the pesticides were <3%. Considering the consumption of crown daisy, they are not considered to be of toxicological concern.

• BioChip Journal
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• v.12 no.4
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• pp.326-331
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• 2018

Contamination by pesticides is an everincreasing problem associated with fields of environmental management and healthcare. Accordingly, appropriate treatments are in demand. Pesticide detection methods have been researched extensively, aimed at making the detection convenient, fast, cost-effective, and easy to use. Among the various detecting strategies, paper-based assay is potent for real-time pesticide sensing due to its unique advantages including disposability, light weight, and low cost. In this study, a paper-based sensor for chlorpyrifos, an organophosphate pesticide, has been developed by layering three sheets of patterned plates. In colorimetric quantification of pesticides, the blue color produced by the interaction between acetylcholinesterase and indoxyl acetate is inhibited by the pesticide molecules present in the sample solutions. With the optimized paper-based sensor, the pesticide is sensitively detected (limit of detection =8.60 ppm) within 5min. Furthermore, the shelf life of the device is enhanced to 14 days after from the fabrication, by treating trehalose solution onto the deposited reagents. We expect the paper-based device to be utilized as a first-screening analytic device for water quality monitoring and food analysis.

• Korean Journal of Medicinal Crop Science
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• v.28 no.6
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• pp.435-444
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• 2020

Background: As the Positive List System (PLS) is implemented in broad application to agricultural products, attention to the correct use of pesticides is also needed in the production of mulberry leaves and fruit. In this regard, three types of pesticides against mulberry popcorn disease were applied 2 - 3 times both in the field and greenhouses to prepare safety standards. Residual pesticide analysis was conducted on mulberry fruits and leaves. Methods and results: Three pesticieds, thiophanate-methyl, thiophanate-methyl·triflumizole and fluopyram registered as PLS pesticides for mulberry popcorn disease, were sprayed in the Wanju and in Buan regions, after which residual pesticide analysis was conducted using high-performance liquid chromatography (HPLC). As three pesticieds were either undetected or below the permissible level in mulberry fruit, demonstrating that they were suitable for safe spraying. However, 5.6 mg/kg of thiophanate-methyl was detected in the greenhouse after three application, which was slightly above maximum residue limit (MRL). Furthermore the level of thiophanate-methyl·triflumizole was higher than 0.2 mg/kg ("Gwasang No. 2" variety, spraying twice) or similar to 0.09 mg/kg ("Daesim" variety, spraying thrice) the permissible level (0.1T mg/kg) as the thiophanate-methyl was detected in mulberry leaves in the greenhouse. Conclusions: The spraying frequency for controlling mulberry popcorn disease in greenhouses should be limited to two times or less, especially when mulberry leaves are treated with thiophanate-methyl·triflumizole careful consideration is required if the leaves are to be used as food materials.

• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.420-429
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• 2023

GC-MS/MS using liquid-liquid extraction (LLE) and C18 cartridges was used to identify and quantify levels of chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin and permethrin in bulk raw milk. A calibration curve spanning 10 ng/mL to 200 ng/mL was obtained with a satisfactory correlation coefficient of 0.99. The limits of detection (LOD) and limits of quantitation (LOQ) for chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin, and permethrin in the matrix ranged from 0.06 to 1.81 ng/mL and 0.19 to 6.04 ng/mL, respectively. The recoveries of 5 pesticides from spiked samples at 37.5-125 ng/mL ranged from 86.1 to 102.1%. The measurement of uncertainty of the GC-MS/MS method for these five pesticides was developed based on the analytical process and quantification. An analysis method that is easier and faster than the method specified in the Korean food standards codes for analyzing these five pesticides in raw material milk was developed. Moreover, the analytical method for chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin, and permethrin in bulk raw milk by GC-MS/MS was established.

• Toxicological Research
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• v.30 no.3
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• pp.159-168
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• 2014

Pesticides have provided significant benefits including plant disease control and increased crop yields since people developed and utilized them. However, pesticide use is associated with many adverse effects, which necessitate precise toxicological tests and risk assessment. Most of these methods are based on animal studies, but considerations of animal welfare and ethics require the development of alternative methods for the evaluation of pesticide toxicity. Although the usage of laboratory animals is inevitable in scientific evaluation and alternative approaches have limitations in the whole coverage, continuous effort is necessary to minimize animal use and to develop reliable alternative tests for pesticide evaluation. This review discusses alternative approaches for pesticide toxicity tests and hazard evaluation that have been used in peer-reviewed reports and could be applied in future studies based on the critical animal research principles of reduction, replacement, and refinement.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.74-78
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• 2012

Envioronmental concerns by use of chemical pesticides have increased the need for alternative method in the control of plant-parasitic nematodes. Biological control is considered eco-friendly and a promising alternative in pest and disease management. A wide range of organisms are known to be effective in control of plant-parasitic nematodes. Fungal biological control is a hopeful research area and there is constant attention in the use of fungi for the control of nematodes. In this review, plant-parasitic nematodes with reference to soils and biological control and nematophagous fungi are dicussed.

• Journal of Acupuncture Research
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• v.29 no.2
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• pp.9-14
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• 2012

Objectives : This study was designed to evaluate the pesticide residue of herb medicine through high density ozone water cleaning system. Materials and Methods : We purchased ginseng(Panax ginseng) on market and sprayed pesticides (Diazinon) on ginseng. We analyzed pesticide residue according to washing methods(untreated, ozone water cleaning, ultrasonic cleaning, Water cleaning). As a result of each washing methods, in ozone water cleaning method pesticide residue was much less remained than in Ultrasonic Cleaning method and water cleaning method. Conclusions : High density ozone water cleaning is the best method for removing pesticides of herbal medicine.