• Journal of Soil and Groundwater Environment
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• v.11 no.4
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• pp.18-24
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• 2006

The possibility of multiresidue analysis of 24 pesticides out of 30 residual pesticides which are subjected to test in the golf courses was examined. The utility of multiresidue method for pesticide residue test was evaluated by recovery test through a standard addition method of pesticides in water, soil, and lawn grass. The experimental results of the recovery test for individual pesticides are as follows : The number of pesticide of which average recovery rate was over 70% regardless of media was 16 pesticides. These pesticides were composed of 8 organophosphorus pesticides (chlorpyrifos, chlorpyrifosmethyl, diazinon, EPN, fenitrothion, phenthoate, phosalone, and toclofos-methyl). 4-organochlorinated pesticides (daconil, captan, endosulfan, and tetradifon), 2-pyrethroid pesticides(fenpropathrin, lambda-cyhalothrin) and 2 other pesticides (bromopropylate, pendimethalin). On the other hand, in case of dicofol, average recovery rate was over 70% for water and lawn grass but only 53.3% for soil. Therefore, the multiresidue method applied in this experiment is not appropriate for analysis of dicofol in soil. Furthermore, among 7 pesticides, 2 pesticides(amitraz and pyraclofos) showed that theirs average recovery rate deviated from criteria($70{\sim}130%$) in almost ail media, while 5 pesticides(bensulide, deltamethrin, iprodione, phosphamidon and tralomethlin) were not detected from all media by GC/NPD or GC/ECD.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.311-315
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• 2005

The simultaneous or consecutive product analysis is needed for quality control because the various items are produced in pesticide manufacturer. This study was conducted to establish a multi-pesticide analysis making possible to analyze several active ingredients with one injection of mixed active ingredients under same instrument-condition in the cause of quality control with accuracy and speed. The test was conducted with 3 pesticides, iprobenfos 17%GR, isoprothiolane 12%GR, tebufenozide 20%SC and performed by GLC and HPLC. With the GLC method, 2 active ingredients of iprobenfos and isoprothiolane were analyzed but tebufenozide was not detective simultaneously. With the HPLC method, all of the active ingredients in those three pesticides were simultaneously analyzed in this study.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.104-127
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• 2016

A new analytical method has been developed to determine 320 pesticides in apple and rice. The extraction of pesticides was carried out based on QuEChERS sample extraction, and determination was performed using LC-MS/MS and GC-MS/MS. 320 pesticides were selected for experiments. 251 and 110 pesticides among them were analysed by LC-MS/MS and GC-MS/MS, respectively. 41 pesticides of them were analyzed by both GC-MS/MS and LC-MS/MS. Among pesticides analysed by LC, 242 pesticides (96% of total number) in apple and 237 pesticides (94% of total number) in rice showed recoveries in the range of 70~120% with RSD ${\leq}20%$. In case of pesticides analyzed by GC-MS/MS, 103 pesticides (94% of total number) in apple and 83 pesticides (76% of total number) in rice were successfully validated. These results indicated that LC-MS/MS and GC-MS/MS analysis with the QuEChERS sample preparation can be partly applied to multi-residue pesticides in agricultural products.

• 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.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.304-307
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• 2005

Multiresidue method was set up for the simultaneous determination of various residual pesticides in potatoes and carrots, which was analyzed by gas chromatography-electron capture detector/nitrogen phosphorus detector. Method consisted with acetone/acetonitrile (9 : 1) extraction and dichloromethane partition, followed by florisil cartridge purification with hexane/dichloromethane/acetonitrile (50 : 45 ; 5) elution. Among 197 pesticides (194 kinds) spiked to food materials, 143 and 155 pesticides were recovered over 70% on potatoes and carrots, respectively. Nineteen pesticides including bromacil, cyproconazole, were not detected in water and sample matrices. Matrix components may affect the low detections of 25 pesticides such as benfuracarb, bitertanol from potatoes and 16 pesticides such as bitertanol, carbosulfan from Carrots. Some pesticides including dichlobenil, fluoroimide and iprodione were highly detected from one or both matrices even though they were not detected from water.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.162-167
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• 2013

An analytical method for the simultaneous determination of pencycuron in agricultural products was established by using GC-NPD. The method was validated through the guidelines of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision. The calibration curve of pencycuron was linear over the concentration range of 0.02-2 mg/kg with correlation coefficient of above 0.9999. The limits of detection and quantification were 0.005 and 0.02 mg/kg. Mean recoveries of pencycuron for each sample were 79.6-107.5% at the level of 0.02 mg/kg and 86.4-112.1% at the level of 0.2 mg/kg and 84.0- 104.9% at the level of 1 mg/kg. Relative standard deviation (RSD) in recoveries were all less than 5%. The intra- and inter-day precision (RSD) were 1.6-3.0% and 5.3-11.5%, respectively. The result of validation indicated that this method was accurate and sensitive assay.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.473-474
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• 2006

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.192-200
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• 2009

Soil testing is one of the best management practices for sustainable agriculture. Recently, as increasing soil testing needs, simplification of soil analytical procedure has been required. To determine recommendable multi-element extractant, the soil testing results of available phosphate and exchangeable cations between the conventional methods (Lancaster and 1M $NH_4OAc) and multi-element extraction methods such as Mehlich III, Modified Morgan and Kelowna methods were compared. There were highly significant correlation between the conventional methods and multi-element extraction methods (Mehlich III, Modified Morgan and Kelowna) for available phosphate and exchangeable K, Ca, Mg and Na. The coefficients of determination ($R^2) between available phosphate extracted by Lancaster method and multielement extraction methods were in the order of Mehlich III ($0.979^{***}$) > Kelowna ($0.977^{***}$) > Modified(Mod.). Morgan ($0.553^{***}$). For exchangeable cations, there were highly significant correlations between 1M $NH_4OAc method and Mehlich III, Mod. Morgan and Kelowna. However, exchangeable K, Ca and Mg by Mehlich III method were more highly correlated with conventional method than other methods. Therefore, Mehlich III extraction method could be recommended as a single extractant for simultaneous measurement using ICP in the analysis of avaliable phosphate and exchangeable cations.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.278-295
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• 2014

Fast and accurate multi-residue pesticides inspecting method needs in Agro-Fishery Products Inspection Center. So, We tried to seek the optimum method using GC-TOF/MS, GC-ECD, GC-NPD after QuEChERS sample preparation. In GC-TOF/MS, 138 kinds of pesticide were spiked at 0.3 and $0.5{\mu}g/g$for the identification and quantification in lettuce sample. Recoveries of 77 pesticides were between 70 and 130% with RSD (relative standard deviation lower than 20% at $0.3{\mu}g/g$. In GC-ECD, NPD, 146 kinds of pesticide were spiked for the identification and quantification in lettuce. Recoveries of 61 species were between 70 and 130% with lower than 20%. These results indicated that GC-TOF/MS, GC-ECD, NPD analysis with the QuEChERS sample preparation can be partly applied to multi-residue pesticides in vegetables.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.296-313
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• 2014

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) multiresidue method was developed for the simultaneous analysis of 124 pesticides in soil by LC-MS. The procedure involved liquid extraction of soil immersed with 0.2N $NH_4Cl$ by acetonitrile with 1% acetic acid, followed by anhydrous $MgSO_4$ and sodium acetate, and dispersive SPE cleanup with $MgSO_4$, primary secondary amine (PSA) and $C_{18}$. The extracts were analyzed with LC-MS/MS in ESI positive mode. Standard calibration curves were made by matrix matched standards and their correlation coefficients were higher than 0.99. Recovery studies for the validation were carried out using two type soils, loam and sandy loam, at four concentration levels (0.005, 0.01, 0.02, and 0.1 mg/kg). The recoveries of pesticides were in the range of 70-120% with < 20% RSD except 4 pesticides, Benfuracarb, Ethiofencarb, Pymetrozine, and Pyrethrin. This result indicated that the method using QuEChERS and LC-MS/MS could be applied for the simultaneous determination of pesticide residues in soils.