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Tenebrio molitor larvae (mealworm) is an edible insect and is considered a future food. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a novel method for simultaneous analysis of 353 target analytes was developed and validated. Various sample preparation steps including &ldquo, quick, easy, cheap, effective, rugged, and safe&rdquo, (QuEChERS) extraction conditions, number of acetonitrile-hexane partitions, and dispersive-solid phase extraction (dSPE) sorbents were compared, and the optimal conditions were determined. In the established method, 5 g of homogenized mealworms was extracted with acetonitrile and treated with QuEChERS EN 15662 salts. The crude extract was subjected to three rounds of acetonitrile-hexane partitioning, and the acetonitrile layer was cleaned with C18 dSPE. The final solution was matrix-matched and injected into LC-MS/MS (2 &mu, L). For target analytes, the limits of quantitation (LOQs) were &le, 10 &mu, g/kg, and the correlation coefficient (r2) of calibration was &gt, 0.990. In recovery tests, more than 90% of the pesticides showed an excellent recovery range (70&ndash, 120%) with relative standard deviation (RSD) &le, 20%. For more than 94% of pesticides, a negligible matrix effect (within &plusmn, 20%) was observed. The analytical method was successfully applied and used for the detection of three urea pesticides in 4 of 11 mealworm samples.

The proficiency testing for the residue laboratories of pesticide registration was conducted inorder to improve the reliability and the ability for pesticide residue analysis. On November 2012 the testingwas carried out using the soil collected and kept as the moistened state for five years, which was expected tovery low residue levels of pesticides. The soil was fortified with azoxystrobin, imidacloprid and methabenz-thiazuron in a manner similar to prepare soil samples for indoor soil degradation test, and then sub-sampleswere prepared for the distribution to participants. Some of them were randomly selected for confirm ofhomogeneity and to ensure the stability of samples at room temperature. Samples were consisted of two soilstreated as different levels, one of which was used to the assessment and another used to confirm. In addition,provided three standard solutions, respectively concentration of 10 mg/L, and untreated soil. Forty eightinstitutions submitted results. The medians of results were used as the assigned values for pesticide residues.Fitness for purpose standard deviation of proficiency test was calculated by applying 20% RSD as thecoefficient of variation allowed in the soil residue test. Z-score was applied for evaluation of individualpesticides, and the average of the absolute value of the Z-score for the overall assessment of pesticides.Laboratories evaluated the absolute value of the Z-score less than 2 to fit the case of azoxystrobin were 48,imidacloprid and methabenzthiazuron 46.Key words pesticide, residue analysis, quality assurance, proficiency test

Pesticide is used to protect the crops, but also become a cause of polluting the environment.Perform a risk assessment using physical and chemical properties, environmental fate and toxicity data inorder to determine the pesticide registration. The aquatic model estimates pesticide concentrations in waterbodies that result from pesticide applications to rice paddies and apple orchard. The used models are thePRZM, EXAMS and AGRO shell (PA5), Rice Water Quality Model (RICEWQ) and Screening ConcentrationIn GROund Water (SCI-GROW). The residual concentration of water body was estimated using meteorologicaldata, crop calendar and soil series of Korea. The chosen pesticides were butachlor, carbofuran, iprobenfos andtebuconazole. It has shown the potential that the RICEWQ is possible to predict residue level in water ofbutachlor and iprobenfos, because the maximum value in water monitoring data is lower than the peakconcentration of the model, and the minimum value is lower than the average annual concentration of themodel. But RICEWQ was insufficient to predict exposure concentrations in ground water. The estimatedexposure concentrations of carbofuran in ground water is very higher than in surface water because of its lowsoil adsorption coefficient. Although tebuconazole were not detected in the water monitoring that means verylow concentration, it is possible that the PA5 can be used to predict residue level in water.Key words rice paddies, water model, RICEWQ, SCI-GROW, PA5

In this study, we monitored the residues of organophosphate pesticides (OP) in eight fruitvegetables grown in Korea, and assessed risk levels of acute and chronic exposure of OP through theconsumption of fruit vegetables. Chlorpyrifos, EPN, methidathion and phosphamidon in eight fruit vegetableswere detected in this study. The results of cumulative assessment of national estimated short term intake foracute exposure of OP were due to the following order; eggplant, tomato, squash and cucumber. Totaltheoretical maximum daily intake calculated at first step of chronic exposure assessment for registered OP inKorea was 76.14%, compared with acceptable daily intake ADI) based on chlorpyrifos. In addition, totalnational estimated maximum daily intake calculated at second step of chronic exposure assessment was13.949%, compared with ADI. Third chronic assessment was conducted by probabilistic approach using OPresidues detected in eight fruit vegetables and showed that total exposure risk was very low, corresponding to0.0001% compared to ADI. Based on those finding, the risk of organophosphate pesticides in fruit vegetableswas considered quantitatively negligible. In future, further investigation to expand the target should befollowed to do more accurate and detailed risk assessment.Key words acute and chronic exposure assessment, fruit vegetables, organophosphate pesticide

This study was carried out to investigate the pesticide residue pattern among different leafyvegetables applied with foliar spraying under greenhouse and to check extrapolating from some residue trialdata to other minor crops. Leafy vegetables used in this study were: Mustard greens (Brassica juncea L.),Kale (Brassica oleracea L.), Dacheongchae (a kind of pak-choi (Brassica rapa subsp. chinensis L.)), Leafbroccoli (Brassica oleracea var alboglabra), Perilla leaf (Perilla frutescens (L.) Britton var. Frutescens), Leaflettuce (Lactuca sativa L.), Swiss chard (Beta vulgaris L. subsp. vulgaris) and Red leaf chicory (Cichoriumintybus L. var. foliosum Hegi). These are cultivated all year under indoor or outdoor and cut the leaf fromplant continuously during harvest time. The amounts of pesticide deposit in/on the continuous harvestingleafy vegetables were affected by the ratios of leaf area to weight. Ratio of perilla leaf was the largest amongcrops as 58 cm 2 /g. The residue levels of 7 pesticides in/on perilla leaf were the highest than those of othercrops through the statistical analysis from zero day to fifth day after last application. The representative cropin 8 crops was perilla leaf selected based on the amounts of daily consumption and the high residues. This studysuggest that the continuous harvesting leafy greens should be separated from the one time harvesting leafyvegetables for the pesticide recommendations because of different harvesting habits and pre-harvest intervals.Key words Extrapolation, Perilla leaf, Leafy vegetables, Pesticide residue, Continuous harvesting

Flonicamid was a water-soluble and systemic insecticide. It was applied to control neonicotinod pesticide-resistant cotton aphid in sweet peppers. However, the residue levels of total flonicamid in sweet pepper exported to Japan in 2009 were exceeded the maximum residue limit (MRL). This study was conducted to elucidate residual properties of flonicamid parent compound and its metabolites in sweet peppers. It was carried out to compare the variation of residues in sweet pepper in three different greenhouses for 21 days after 3 times application with 7 days interval. The mean residues were 0.176, 0.152 and 0.108 mg kg and the residue levels in sweet pepper among three greenhouses show significant difference. The maximum residue levels were detected 10 days later after last treatments. The overall residue levels were lower than MRL 2.0 mg kg (by Korea) and 0.4 mg kg (by Japan in 2009 but now revised MRL is 2.0 mg kg ). But the residue level of total flonicamid at the 21th day after 3 times treatment with 7 days interval was 0.429 mg kg restricted by the application of double rate than recommended rate. The amounts of metabolites, TFNA, 4-Trifluoro methyl nicotinic acid and TFNG, N-(4-trifluoro methyl nicotinoyl) glycine were increased while flonicamid parent compound was decreased over time. Therefore the longer trial period should be needed for flonicamid in sweet peppers.

The proficiency testing for the residue laboratories of pesticide registration was conducted in order to improve the reliability and the ability for pesticide residue analysis. On October 2011 the testing was carried out using the soil collected and kept as the moistened state for five years, which is expected to very low residue levels of pesticides. The soil was fortified with chlorpyrifos, metolachlor and procymidone in a manner similar to prepare soil sample for indoor soil degradation test, and then sub-samples were prepared for the distribution to participants. Some of them were randomly selected for confirm of homogeneity and to ensure the stability of samples at room temperature. Samples were consisted of two soil treated as different levels, one of which was used to the assesment and another used to confirm. In addition, provide three standard solutions, respectively concentration of 10 mg/L, and untreated soil. Forty seven institutions submitted results. The medians of results were used as the assigned values for pesticide residues. Fitness for purpose standard deviation of proficiency test was calculated by applying 20% RSD as the coefficient of variation allowed in the soil residue test. Z-score was applied for evaluation of individual pesticides, and the average of the absolute value of the Z-score for the overall assessment of pesticides. Laboratories evaluated the absolute value of the Z-score less than 2 to fit the case of chlorpyrifos and procymidone were 44, metolachlor 40.

In order to use in the classification of minor crop for the mutual application of safe use guideline, it was investigated the residue property of fungicide dimethomorph and pyraclostrobin in green onion, a stem-crop. After pesticides were applied 2 times with 1 week interval in that day of harvest, 3 days, 7 days, 10 days and 14 days before harvest, a green onion was harvested. The residue of dimethomorph in a green onion was 26.31 and 39.08 mg/kg in that day of harvest, however, in according to elapse time, it was reduced to 6.86 and 9.34 mg/kg in 14 days before harvest. In case of pyraclostrobin, it was also reduced from 13.46 and 39.08 mg/kg to 3.57 and 5.21 mg/kg. Based on the residue in that day of harvest, the deposit of spray solution in a green onion was calculated. The deposit of spray solution of dimethomorph was 274.35~345.84 mL/kg, in case of pyraclostrobin, it was calculated 213.65~343.33 mL/kg. When the amount of the deposit of both pesticides was compared in a green onion, it was so similar. On the other hand, it was estimated the predicted dissipation curve of pesticides in the green onion during cultivation. The half-life of dimethomorph was 6.95~7.45 days, in case of pyraclostrobin, 7.15~7.45 days. When both pesticides were compared with the residue property, the deposit of spray solution and half-life of dissipation were so similar.

This study was carried out to clarify the effects of the application of pesticide by different spray nozzle types on pesticide residues. The average droplet size and discharge rate were investigated when the manual compressed sprayer with two head disk type nozzle and the knapsack engine powered sprayer with two head fan shape nozzles were used. The fan type nozzles were classified into three types by the number of orifice in the nozzle. Three type nozzles tested were fan with one orifice, fan with two orifices and fan with three orifices. Fan (trade name : D-3) with 2.4 L/min. of the discharge rate and 76 µm of the average droplet size while maintaining constant pressure 1.1 ± 0.2 MPa, and fan D-35 with 2.6 L/min. and 90 µm while maintaining constant pressure 1.0±0.2 MPa were appropriate. The orifice size of D-3 was 0.65 mm length × 0.45 mm width and the orifice size of D-35 was 0.62 mm length × 0.46 mm width. The residue levels of imidacloprid on perilla leaves among four applications by four different nozzles show significantly difference with 5% significance level. The residue levels 3.76~3.92 mg kg �1 by fan or disk type is smaller than 4.52~4.92 mg kg �1 by fan II or fan III. The residue levels of imidacloprid on perilla leaf were different

This study was carried out in order to compare the residue levels of pesticides among lettuce,kale and perilla leaf depending on the morphological characteristics of plant. Residue levels were investigatedat the zero, second, fifth days after last application, 9 species of systemic or non-systemic pesticide weretwice applied with 7 days interval by knapsack power sprayer with 2 heads fan shape nozzle. Ratios of leafarea to weight (cm 2 g -1 ) were 58 of perilla leaf, 27 of lettuce and 23 of kale. Ratios of leaf area to weight ofperilla leaf was 2.1 times higher than that of lettuce. Residue levels of perilla leaf were 1.3 to 2.3 timeshigher than those of lettuce at the day of spraying and 1.3 to 3.3 times higher at the fifth day. Therefore thedifferences of pesticide residues between perilla leaf and lettuce were affected by the ratio of leaf area toweight. Residue levels in lettuce were 2.4 to 7.3 times higher than those in kale at the day of sprayingbecause the adhesive effect of pesticide particles on kale leaf was low.Key words Perilla leaf, Lettuce, Kale, Pesticide, Residue amount

Fate of acetamiprid and imidacloprid aerially sprayed to control pine wood nematode (Bursaphelenchus xylophilus) were studied in a forest of Haman area. Acetamiprid 20% SL or imidacloprid 20% DC were diluted 100 times and applied two times as rate of 50 L/ha using an aircraft of Bell 206 L helicopter. Average acetamiprid deposits on forest floor ranged from 2 to 4% of standard aerial application rate. Following to the second application, acetamiprid deposits in the pine needle ranged 1.8~8.5 mg/kg and then gradually decreased to 1.2~2.1 mg/kg after 48 days. Deposits on the plant washed off by rainfall and reached to soil surface was ca. 17% of the application rate. All of acetamiprid on the ground resided in the forest floor covering the soil surface, where acetamiprid residues were decreased to a quarter at 48 days after the second application, but they were not detected in soil beneath it. And the only low level of acetamiprid residues, 0.0003 mg/L, was detected in the reservoir nearby the experimental forest on the day of aerial application. The acetamiprid detection was presumably due to spray drift. And average imidacloprid deposits on forest floor ranged from 1 to 3% of standard aerial application rate. Following to the second application, imidacloprid deposits in the pine needle analysed very low concentration of 0.1 mg/kg, but the amount of imidacloprid in wash-off in standard and two-fold treatment were ca. 8% and 4% of the application rate, respectively. Most of imidacloprid on the ground also resided in the forest floor, where imidacloprid residues were decreased to a twentieth at 111 days after the second application, and they were detected below 0.5% of the application rate in sol beneath it. And the low level of imidacloprid, 0.0003~0.0017 mg/L, were detected in the streams in the experimental forest. It was not to the level of contamination concerns.

In order to use in the classification of minor crop for the mutual application of safe use guideline, it was compared a green onion with a scallion on the residue property of insecticide bifenthrin and chlorfenapyr. After pesticides were applied 2 times with 1 week interval in that day of harvest, 3 days, 7 days, 10 days and 14 days before harvest, vegetables were harvested, and the residue of pesticides was investigated. Base on the residue in that day of harvest, the deposit of spray solution in vegetables was calculated. The deposit of spray solution of bifenthrin was 123.0 mL/kg in a green onion, and 74 mL/kg in a scallion. In case of chlorfenapyr, it was calculated 126.5 mL/kg in a green onion, and 70.0 mL/kg in a scallion. When the amount of the deposit of both pesticides was compared a green onion with a scallion, it was higher in a green onion. On the other hand, it was estimated the predicted dissipation curve of pesticides in a green onion and a scallion during cultivation. The dissipation curve of bifenthrin was y = 1.0334 e�0.0602x (R 2 = 0.8606) in a green onion, and y = 0.7693 e �0.1823x (R 2 = 0.9756) in a scallion. In case of chlorfenapyr, it was y = 2.2603 e �0.0519x (R 2 = 0.9043) in a green onion, and y = 1.2940 e �0.1051x (R 2 = 0.9782) in a scallion. The half-life of bifenthrin was 11.51 days in a green onion, and 3.80 days in a scallion, respectively. Also, it was estimated half-life in chlorfenapyr, it was 13.35 days in a green onion, and 6.59 days in a scallion, respectively. The half-life of both pesticides in a green onion was longer than in a scallion. When both vegetables were compared with the residue property, the deposit of spray solution and half-life of dissipation in a green onion were more than those in a scallion.

This study was carried out to clarify effects of field location and sprayer on the level of pesticide residue in chilli peppers. As confirmed by statistical analysis, the residue levels in green pepper among three greenhouses did not show significant difference at the first day after spraying with the same engine sprayer and nozzle. But the residue levels in green peppers collected from the exposed outside of crop were 2 times higher than those from the hidden inside. The sampling site was one of variation elements of pesticide residue. The residue levels after application by knapsack engine powered sprayer were 1.7 times higher than those by manual compressed sprayer. As the spraying pressure of the engine power sprayer is 2 times higher than the commonly used pressure of the manual compressed sprayer, the pressure of the sprayer and nozzles were considered to affect on the residue levels in peppers.

The characteristics of chlorpyrifos was studied to clarify the effect of the cultivation season,spray intervals, spray volume and concentration on residues in chilli and sweet peppers cultivated undergreenhouse condition. Residue levels of chlorpyrifos detected in chilli pepper fruit cultivated were 1.5 to 2.7times higher in winter(February-March) than those in summer(June-July). During winter season residue levelsof chlorpyrifos in chilli peppers were 6.9~3.2 times higher than those in sweet peppers for 10 days after 3times application with 7 days interval. Residue levels in chilli pepper were from 2.070 mg/kg at 1 day to0.929 mg/kg at 10 day, while those in sweet pepper were from 0.302 mg/kg to 0.291 mg/kg. Residue levels insweet pepper to which are 3 times applied with 7 days interval were from 0.302 mg/kg at 1 day to 0.291 mg/kg at 7 day, and the residue levels in sweet pepper which are 3 times applied with 3 days interval were from0.498 mg/kg at 1 day to 0.470 mg/kg at 7 day. Residue levels of chlorpyrifos in the sweet peppers applied bydouble concentration were 2.5 times higher than those sprayed by normal standard amounts diluted in doublevolume. Key words Chlorpyrifos, Sweet pepper, Chilli pepper, Pesticide residue

Department of Agro-Food Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, KoreaIn order to use in the classification of minor crop for the mutual application of safe use guideline, it was investigated the residue property of fungicide boscalid and fludioxonil at the same time harvest leafy-vegetables, such as spinach, ulgaribaechu, vitaminchae and cheongkyungchae. After pesticides were applied 2 times with 1 week interval in that day of harvest, 2 days, 5 days and 7 days before harvest, vegetables were harvested, and the residue of pesticides was investigated. Base on the residue in that day of harvest, the deposit of spray solution in vegetables was calculated. The deposit of spray solution of boscalid was 253.9 mL/kg in spinach, 83.0 mL/kg in ulgaribaechu, 97.8 mL/kg in vitaminchae, and 88.3 mL/kg in cheongkyungchae, respectively. In case of fludioxonil, it was calculated 157.6 mL/kg in spinach, 67.6 mL/kg in ulgaribaechu, 64.8 mL/kg in vitaminchae, and 66.6 mL/kg in cheongkyungchae, respectively. When the amount of the deposit of both pesticides was compared in leafy-vegetables, it was the highest in the spinach. On the other hand, it was estimated the predicted dissipation curve of pesticides in leafy-vegetables during cultivation. The half-life of boscalid was 5.9 days in spinach, 7.4 days in ulgaribaechu, 4.6 days in vitaminchae, and 4.3 days in cheongkyungchae, respectively. Also, it was estimated half-life in fludioxonil, it was 3.0 days in spinach, 4.0 days in ulgaribaechu, 3.2 days in vitaminchae, and 3.5 days in cheongkyungchae, respectively. The half-life was the longest in the ulgaribaechu. When both pesticides were compared with the residue property, the deposit of spray solution and half-life of dissipation of boscalid were more than those of fludioxonil.Key words Boscalid, Fludioxonil, At the same time harvest leafy-vegetables, Deposit of spray solution, Half-lifeAbstract

Ponticulothrips diospyrosi Haga et Okajima has several characteristic features of damage, such as leaf rolling and dotted scars on fruit skin. The objectives of this study were to find out the optimum timing and frequency of insecticide application to reduce this damage. The effect of spraying twice at a 7-day interval before adult immigration was tested. The efficacy of the insecticide was delayed by the favorable microhabitat produced by adults and offspring within damaged leaf. Twice spraying in 2005 was effective in reducing the number of surviving insects and damaged leaves 1 month later. The time of adult immigration was coincident with the growth of persimmon shoots to 2 cm approximately, or the stage of four to five leaves, on April 22. Spraying three times in 2006 was the most effective, starting the first spray at the five to six leaf stage, immediately before immigration, and the second 9 days later (on immigration), and the third after the flowers faded. By using this control regime, no leaves were damaged, and residues of thiamethoxam and its metabolite were trace levelled when they were analysed by HPLC in late October. The growers could obtain the highest portion of marketable fruits, > 99%, yielding an acceptable net income.