• Analytical Science and Technology
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• v.34 no.1
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• pp.1-8
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• 2021

An analytical method was developed and optimized for the quantification of a plant growth regulator, 2,6-diisopropylnaphthalene (2,6-DIPN), in agricultural products using gas chromatography-tandem mass spectrometry. The samples were extracted, partitioned, and were purified using a Florisil® cartridge. To validate the analytical method, its specificity, linearity, limit of detection (LOD) and limit of quantification (LOQ) of the instrument, LOQ of the analytical method (MLOQ), accuracy, and repeatability were considered. The method displayed excellent results during validation, and is suitable for the determination and quantification of the low residual levels of the analyte in the agricultural samples. All of the results with the optimized method were satisfactory and within the criteria ranges requested in the Codex Alimentarius Commission guidelines and the Ministry of Food and Drug Safety guidelines for pesticide residue analysis. The developed method is simple and accurate and can be used as a basis for safety management of 2,6-DIPN.

• Journal of Environmental Science International
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• v.19 no.8
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• pp.941-949
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• 2010

The three electrode system was used to detect the pesticide fenitrothion ($C_9H_{12}NO_5PS$. MW=277.24) using cyclic voltammetry (CV) and square wave anodic stripping voltammetry (SWASV). The working electrode was mercury immobilized on a carbon nanotube paste electrode (Hg-CNTPE). At the optimized condition, the limit of detection (LoD) was 0.6 ppt ($2.16{\times}10^{-12}\;M$), and the relative standard deviation was 0.035% (n=15). And there is more sensitive in detecting fenitrothion than common type carbon nanotube paste electrode. When it was implanted into the brain of live fish (carp), the existence of fenitrothion was measured without any destruction or damage of tissue.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.19-23
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• 2001

This study was conducted to monitor the residue of the herbicide butachlor in major crops. The residue monitoring covered 106 samples of rice, barley, garlic, onion, and strawberry colledted from markets of intensive cultivation area including Kwangju, Daegu, and Pusan. The residue levels in 27 sample of polished rice produced by applying the herbicide were below the detection limits adopted analytical method. The residue levels in 21 sample of garlic, 18 sample of onion, and 18 sample of strawberry which were succeeding crops after paddy rice were also below the detection limits. In consequent, all the samples resulted safe status in terms of the butachlor residue level in agricultural produce.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1325-1330
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• 2008

This study was carried out with the detection for multiresidue of the carbamate pesticide such as carbaryl and cabofuran by enzyme-inhibition method. The check time for determination of acetylcholinesterase(AChE) activity was selected at 60 sec. The AChE activity in chicken brain determined by the Ellman's method was $162{\mu}$mol/min/g protein. $I_{50}$ for AChE by carbamate pesticide with wet kit was 0.169mg/L of carbaryl and 0.089mg/L of cabofuran, respectively. The incubation time for enzyme kit with substrate kit was 30min for determination of AChE activity. Enzyme kit with substrate kit was stable at $4^{\circ}C\;and\;25^{\circ}C$ for 5 days. Limit detection concentration of carbaryl with dry kit for AChE was 0.05mg/L. The dry kit such as wet kit applied Enzyme-Inhibition(EI) method with AChE was confirmed the multi residue method to detect the carbamate pesticides.

• Journal of Food Hygiene and Safety
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• v.20 no.3
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• pp.165-174
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• 2005

This survey was conducted to monitor the current status of pesticide residues in agricultural products collected in wholesale markets and big retailers in Gwangju, in 2004. A total of 751 samples was analyzed by multiresidue method. Vegetables and fruits accounted for the largest proportion of the commodities analyzed and those two commodity groups comprised 604 $(80\%)\;and\;83\;(11\%)$ of the total number of 751 samples. Of these 751 samples, 112 samples $(14.9\%)$ had pesticide residues and 29 samples $(3.9\%)$ had violative residues. The detection rate was the highest $25\%$ in January and the lowest $9.5\%$ in June. The violation rate was the highest $7.0\%$ in March and the lowest $0\%$ in April. The violation rate in wholesale products was higher than that in big retailer products, $5.8\%$ verses $3.5\%$. And of 112 samples with pesticide residues, the agricultural product in which the pesticide residues were the most flequently detected was perilla leaf $(17.9\%)$ followed by korean lettuce $(16.1\%)$, spinach $(8.0\%)$ and korean cabbage $(5.4\%)$ and among 112 samples, 22 samples $(20\%)$ had more than one pesticide. Procymidone $(20.3\%)$, endosulfan $(18.2\%)$, dimethomorph $(13.3\%)$, chlorpyrifos $(7.7\%)$ and azoxystrobin $(6.3\%)$ were the most frequently found in agricultural product analyzed.

• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.311-322
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• 2003

This study was carried out to investigate the 106 kinds of pesticide residues in agricultural products (n=3,614) by GC, for the northern area of Seoul from March (1999) to December (2000). The detection rate of pesticide residues in samples was 5.0% (mean =2.86$\pm$7.22 mg/kg, n=180). The order of the agricultural products in which pesticide residues were detected was korean lettuce > perilla leaf, pepper > chinese cabbage > leek > spinach. The percentage of the agricultural products in excess of MRL was 2.0% (n=73). The agricultural products in excess of MRL were korean lettuce (n=15), perilla leaf(n=13), leek (n=6), spinach (n=6), pepper (n=5), chwinamul (n=5), etc. The order of the pesticide residues which were detected in agricultural products was procymidone endosulfan chlorpyrifos vinclozolin chlorothalonil and diazinon. The average residual values of procymidone, endosulfan, chlorpyrifos, vinclozolin, chlorpyrifos, and diazinon were 4.07, 1.24, 1.27, 2.83, 17.71 and 1.48 respectively. The pesticide residues in excess of MRL were chlorpyrifos (n=19), endosulfan (n=12), procymidone(n=), vinclozolin (n=6), etc, and the measured concentration ranges of chlorpyrifos, endosulfan, procymidone, vinclozolin, pyrazophos, diazinon and EPN were 0.03-6.72, 0.18-5.8, 2.0-60.8, 1.70-20.33, 0.26-1.21. 0.59-4.3 and 0.28-4.19 respectively.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.133-147
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• 2009

In order to develop the simultaneous analytical method for pesticide residues which ones in soil are rapidly and inexpensively measured by, many analytical methods for individual pesticide residue and several methods for multi-pesticide residues in agricultural commodities and food were reviewed. Various gas chromatographic conditions and pre-treatment procedures were intensively investigated and modified. And then new optimum procedure was established and its proficiency was validated. The response on detectors of simultaneous determination of 180 pesticides out of pesticides used in Korea was tested. The number of pesticides that their limits of detection (LOD) equal or lower than $0.05\;mg\;kg^{-1}$ were 137 pesticides on ECD, 170 pesticides on NPD and 179 pesticides on ECD/NPD integrated. The retention times of most pesticides ranged appropriately between 10 minutes and 40 minutes in the proposed chromatographic conditions. But about 90 pesticides eluded between 20 minutes and 30 minutes and so they were not resolved enough. In partition with dichloromethane, ethyl acetate/hexane (1:1) and ethyl acetate, number of pesticides whose extraction efficiency ranged from 70% to 120%, were 163, 154 and 147, respectively.

• Journal of Food Hygiene and Safety
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• v.38 no.4
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• pp.202-210
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• 2023

To analyze the pesticide residues in commercial bee pollen products in South Korea, 61 samples were collected and screened for 339 pesticides. Results revealed that approximately 34% (>LOQ) of samples were contaminated with at least one pesticide. The pesticide residue detection rates of domestic and imported samples were 31% and 44%, respectively. Furthermore, the pesticide residue detection rate of online distribution (60%) was higher than that of offline distribution (27%). Fifteen pesticides were discovered in bee pollen, and pendimethalin, chlorfenvinphos, chlorpyrifos, and fluazinam were detected in 7, 6, 3, and 2 order of frequency, respectively. Even though its concentration was low, chlorfenvinphos which is banned in food crops in the United States, European Union, and Korea, was detected in bee pollen samples commonly. Therefore, continuous investigation of pesticide residues in bee pollen products and their acceptance criteria is required for safety.

• 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.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.441-452
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• 2011

This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.