• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.314-334
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• 2013

This study explored an efficient modified Quick, Easy, Cheap, Effective, Rugged and safe (QuEChERS) method combined with liquid chromatography-electrospray ionization with tandem mass spectrometric detection for the analysis of residues of 76 pesticides in brown rice, barley and corn including acidic sulfonylurea herbicides. Formic acid (1%) acid in acetonitrile and dispersive solid phase extractions used for extraction of pesticides and clean-up of the extract respectively. Two fortified spikes at 50 and 200 ng $g^{-1}$ levels were performed for recovery test. Mean recoveries of majority of pesticides at two spike levels ranged from 73.2 to 132.2, 80.9 to 136.8, 66.6 to 143.5 for brown rice, barley and corn respectively with standard error (CV) less than 10%. Good linearity of calibration curves were achieved with $R^2$ > 0.9907 within the observed concentration ranged. The modified method also provided satisfactory results for sulfonylurea herbicides. The method was applied to the determination of residues of target pesticides in real samples. A total of 26 pesticides in 36 out of 98 tasted samples were observed. The highest concentration was observed for tricyclazole at 1.17 mg $kg^{-1}$ in brown rice. This pesticide in two brown rice samples exceeded their MRLs regulated for rice in republic of Korea. Except tricyclazole none of the observed pesticides' concentration was higher than their MRLs. The results reveal that the method is effectively applicable to routine analysis of residues of target pesticides in brown rice, barley and corn.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.6
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• pp.449-456
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• 2022

Recently, fruit farms such as apples tend to have higher productivity and reduce pesticide spraying, and demand in Southeast Asia continues to increase as technology for high-grade work vehicles in the Philippines and Korea's agricultural high-grade work vehicles rise to 3,300mm to 3,800mm, so workers can work at only 4.5m. Therefore, this paper is a study to develop a multi-purpose upright smart high-altitude work vehicle that can secure a work space of more than 7m, up 5.5m, and a structural analysis for design and verification of Multi-purpose Smart Elevation Work Vehicle

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.237-245
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• 2007

We tested for residual pesticide levels in agricultural products purchased from 5 provinces within the middle region of Korea during 2006. A Total of 488 samples of 23 different types of agricultural products were analyzed by GC/MS, GC-NPD, and LC/MS/MS. We used multi-analysis methods to analyze for 231 different pesticide types; a single residual pesticides were detected in 92 samples (18.9%), of which 9 samples (1.9%) exceeded the Korea Maximum Residue Limits (MRLs). we detected pesticide residue in more than 50% of the pepper leaf and welsh onion samples. For the welsh onions, 16 among the 30 analyzed samples contained pesticide residue, and 4 samples exceeded the Korea MRLs. Among the 234 kinds of pesticides we tested for, 42 were detected, and 21 of them were detected more than twice. Six pesticide residue types, including cypermethrin, iprodione, fludioxonil, ethoprophos, flutolanil, and lufenuron, exceeded the MRLs. No residual pesticides were detected in 396 of the samples (81.1%), and the residual pesticide levels in 83 samples (17.0%) were lower than the Korea MRLs, indicating that 98.1% of the samples were relatively safe.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.216-222
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• 2009

The present study aims to monitor pesticide residues in cut flowers collected from the farms and markets. Cut flowers used in this study included rose, lily and chrysanthemum collected from June to September, 2008. Samples were collected once from farms in Hwasung, Goyang (Gyeonggi-do), Inje (Gangwon-do) and thrice from wholesale market in Namdaemunm, Yangjae and Gangnam (Seoul). Total of 24 pesticides (12 fungicides, 11 pesticides and 1 acaricide) were detected from samples collected from farm and total of 64 pesticides (25 fungicides, 36 pesticides, 1 acaricide and 2 fungicides) were detected from samples collected from wholesale market. The highest detection frequency of pesticide from farm was for carbaryl (15%) and for boscalid, fluacrypyrin, fluquinconazole, methomyl, pyraclostrobin, trifloxystrohin (10%), with overall detection of $0.1-36.99\;mg\;kg^{-1}$. While the highest detection frequency of pesticides from wholesale market was for carbaryl, fluquinoconazole and kresoxim-methyl (18.52%), methomyl (16.6%), and methiocarb and thiacloprid (12.96%) with overall detection amount of $0.1-56.2\;mg\;kg^{-1}$. Higher amount of pesticides were detected in leaves than in flowers. Among the pesticides detected, detection frequency of unregistered pesticides for rose, chrysanthemum and lily was 55%, 60% and 63% collected from farms and 47%, 60% and 89% collected from markets, respectively. These pesticides require registration and further monitoring in floricultural crops.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.283-289
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• 2019

This study was performed to monitor the residual pesticides in agricultural products used in school foodservice in the Gwangju metropolitan area. Risk assessment was also carried out based on the amount of agricultural products consumed. A total of 320 agricultural products supplied to schools in Gwangju were analyzed from 2015 to 2017. The pre-treatment and residual pesticide analysis of these products was conducted in accordance with the second method for multi-residue analysis of pesticides in the Korean food code. The hazard index was calculated by dividing the estimated daily intake (EDI) of pesticides by the acceptable daily intake (ADI). The linearity correlation coefficient for the calibration curve was 0.9923 to 1.0000, LOD 0.004 to 0.019 mg/kg, LOQ 0.012 to 0.057 mg/kg, and recovery was 79.1 to 100.2%. Residual pesticides were detected in 18 (5.6%) of 320 agricultural products used for school foodservice, and one sample of sweet potato stem (0.3%) exceeded the maximum residual limit (MRL). The detection frequency for chili peppers and bell peppers was higher than that for other agricultural products. The frequently-detected pesticides were boscalid and acetamiprid. These results showed that residual pesticide management is needed for chili pepper, bell pepper and sweet potato stem among agricultural products supplied to schools. The hazard index of bifenthrin in sweet potato stem showed the highest (64.18%), and the other pesticides were 0.03-8.23%. These results indicated that agricultural products supplied to schools in Gwangju were safe for consumption. To minimize the intake of residual pesticides, it is necessary to not only thoroughly wash agricultural products but to also ensure the expanded supply of products that are pesticide-free.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.242-256
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• 2012

QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method has been a lot of research for pesticide analysis, because it is very simple and fast. However, this method requires high sensitivity instrument such as LC-MS/MS because of the use of small sample volume and many impurities compared to the conventional method. So, QuEChERS method needs to be modified for using with HPLC and GC-ECD/NPD. The aim of this work was to study the application of the QuEChERS method as well as its modification for the extraction and preconcentration of 5 groups of 61 pesticides from 4 fruits prior to their determination by HPLC-PDA, GC-ECD/NPD, and LC-MS/MS. The method was validated using spiking levels at 0.1 mg/kg (or 0.01 mg/kg) in apple, grapes, pear and persimmon. The average recovery by QuEChERS AOAC Official 2007. 01 version using the LC-MS/MS varied from 71.1127.4% for 61 pesticides. The average recovery rates using modified QuEChERS varied from 70.9~126% for 61 pesticides by HPLC-PDA and GC-ECD/NPD. The results satisfied the criteria of multiple pesticide residue analysis, setting 70~130% for recovery rates and below 30% for CV.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.151-160
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• 2015

This study was conducted to monitor residual pesticides in perilla leaf & lettuce and to assess their risk to human health. The total number of perilla leaf & lettuce were 4,063 and 2,248 respectively and these products were collected at the Garak-dong Agricultural & Marine Products Market sold by auction from 2010 to 2012. Multi-residual analysis of 285 pesticides were performed by GC-ECD, GC-NPD, HPLC-DAD and HPLC-FLD. In perilla leaf, 61 pesticides were detected and detection rate was 20.0%. 28 pesticides were detected in case of lettuce and detection rate was 4.8%. In order to do risk assessment by perilla leaf & lettuce consumption, estimated daily intake of residual pesticides were determined and compared to acceptable daily intake, referring to hazard index (HI values). The range of % HI values of perilla leaf was from 0.000% to 0.049%. The range of % HI values of lettuce was from 0.000% to 0.095%. These results show that the risk caused by pesticide residues in perilla leaf & lettuce intake were very low and these vegetable intake was safe.

• Analytical Science and Technology
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• v.23 no.4
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• pp.395-404
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• 2010

A multi-residual method using gas chromatography coupled with mass spectrometry (GC/MS/ MS) was developed for the analysis of 105 pesticides. This method was tested on lemons, beans and other vegetables. The pretreatment of these pesticides was performed by liquid-liquid partition followed by cleanup with solid phase extraction cartridge (SPE Florisil), after acetonitrile extraction from matrices and sodium chloride (15 g) addition. The recovery ranged from 71.1% to 126.0% except for azinphosmethyl, famoxadone, fenamidone, flufenoxuron and triadimefon in lemons and from 72.5% to 124.5% in bean. In lemon, the limit of detection (LOD) and limit of quantification (LOQ) were 0.001~150 ng/ mL and 0.004~500 ng/mL, respectively.

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.13-18
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• 2013

This study was conducted to monitor residual pesticides in ginseng and balloon flower roots and to assess their risk to human health. All of 112 samples consisted of ginseng and balloon roots were purchased from traditional domestic markets and supermarkets in nine provinces of Korea in 2012. Multi-residue analysis of 122 pesticides was conducted and the analysis was performed by gas chromatography-electron capture detector, gas chromatography- nitrogen/phosphorus detector, and high-performance liquid chromatography. Seven pesticides were detected in 12 root samples and the detection rate was 10.7%. The detected twelve root samples were 10 ginseng root samples and 2 balloon root samples. Pesticides detected in root samples were procymidone, kresoxim-methyl, endosulfan, cypermethrin, tralomethrin, tetraconazole and chlorfluazuron. Among them, two pesticides as tetraconazole in a balloon flower root and cypermethrin in a ginseng root exceeded the recommended maximum residue limit set by Korea Food and Drug Administration. Five pesticides detected from 10 root samples were identified as unregistered pesticides in Korea. In order to do risk assessment with Korean medicinal plant consumption, estimated daily intake of residual pesticides were determined and compared to acceptable daily intake, referring to %ADI values. The range of %ADI values was from 0.006% to 0.333%. Taken together, it demonstrates the pesticides found in the two root samples were below the safety margin, indicating no effect on human health.