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Tenebrio molitor larva (mealworms) has recently attracted attention as a protein source for food and feed. The larva is generally fed with wheat bran, which can be possibly contaminated with glyphosate. To establish food safe standards, a rugged and effective analytical method for glyphosate, aminomethylphosphonic acid, glufosinate, and their metabolites including 3-methylphosphinico-propionic acid, and N-acetyl glufosinate, in mealworms was optimized using liquid chromatography tandem mass spectrometry. An anionic polar pesticide column was used due to its high suitability for glyphosate. Acidified water and acetonitrile were used to extract the target compounds without contribution from various fatty and pigment interferences derived from brownish insects. Seven different clean-up procedures ((1) 50 mg C18 (2) 20 mg C18/Z-sep (3) PRiME hydrophilic-lipophilic balance (HLB) cartridge (4) 75 mg Z-sep, (5) 75 mg Z-sep+, (6) EMR-lipid cartridge, and (7) 50 mg ENVI-Carb) were compared. Due to its simplicity and cost-effectiveness, PRiME HLB was selected for clean-up. The recoveries of the target compounds were ranged from 86 to 96% with

Traditionally in Korea, Protaetia brevitarsis seulensis (white-spotted flower chafer) has been used as a medicine, and recently has attracted increased attention due to its antithrombotic efficacy. Some of spent mushroom compost or fermented oak sawdust, a feedstock for P. brevitarsis, were contaminated with three fungicides, carbendazim, dimethomorph, and fenoxanil, which could be transferred to the insect. This study was aimed to optimize a simple extraction method combined with liquid chromatography tandem mass spectrometry and apply it to the real samples. After the pulverized samples (5 g) were extracted with acetonitrile (10 mL) and formic acid (100 μL), fat and lipids in the samples were slowly precipitated at -20°C for 24 hours. After eight different clean-up methods were investigated, the mixture of 150 mg MgSO4/25 mg PSA/25 mg C18 was selected due to optimal recovery of the target compounds. Recovery (77.9%‒80.8% for carbendazim, 111.2%‒116.7% for dimethomorph, and 111.9%‒112.5% for fenoxanil) was achieved with reasonable relative standard deviation (P. brevitarsis before the medical applications.

A quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was developed and combined with liquid chromatography-tandem mass spectrometry to analyze 12 acidic pesticides in cabbage and spinach. The extraction solvents, phase partition salts and sorbents effect was studied to optimize the method followed by dilution before sample injection. The extraction involved 5% formic acid in acetonitrile, and the liquid-liquid partition was salt-induced. Carbopack Z, a high surface area graphitized carbon black, was a new sorbent used in the clean-up. The results show that Carbopack Z effectively removes interferences with little loss of acidic pesticides. All tested pesticide recoveries were satisfactory when Carbopack Z was combined with C18 in the clean-up at optimized condition. After clean-up, the extract was subjected to 10-fold dilution to sufficiently reduce the matrix effect (20%). The limit of quantification (LOQ) was 1-5 ng/g, and the mean recovery was between 95 and 110% with a relative standard deviation20% (between 2% and 10%) for the spiking of three concentrations: 5, 50, and 500 ng/g. The extract was less pigmented in the modified QuEChERS method than its original version. Thus, the modified method is a useful alternative for investigating the acidic pesticide residues in cabbage and spinach.

An effective analytical method was optimized for residues including chlorpyrifos&ndash, methyl, deltamethrin, fenoxanil, thiobencarb and fludioxonil in mealworms, the larval form of Tenebrio molitor. They are listed for pest control during wheat cultivation and can be found in wheat-bran feed for growing mealworms in South Korea. Analytes were extracted using acetonitrile and salt packet. Four clean-up methods ((1) MgSO4 + 25 mg PSA + 25 mg C18, (2) MgSO4 + 50 mg PSA + 50 mg C18, (3) EMR-lipidTM tube, and (4) 10 mL n-hexane) were investigated and the method (1) was selected due to its robustness. Low-temperature precipitation of fat and proteins improved the recoveries. Recoveries from the Method (1) were satisfying with 70&ndash, 120% with &lt, 20% relative SD at a spiking level of 0.01 mg/kg. With the simultaneous sample preparation, fenoxanil, thiobencarb and fludioxonil were analyzed by liquid chromatography tandem mass spectrometry (LC&ndash, MS/MS) and chlorpyrifos&ndash, methyl and deltamethrin by gas chromatography tandem mass spectrometry (GC&ndash, MS/MS). Quantification limits for LC&ndash, MS/MS and GC&ndash, MS/MS were 0.5 and 2.5 &mu, g/L, respectively. No pesticides of interest were detected in 30 real samples collected across the nation. However, the data can be provided for establishing maximum residue limits for the pesticides in mealworms in response to the positive list system.

This study was investigated the change of pesticide residues in young Chinese cabbages andyoung radishes sprayed with pesticides (young Chinese cabbage: diazinon EC, dimethomorph WP andimidacloprid WP, young radish: diazinon EC, imidacloprid WP and procymidone WP) during Kimchipreparation and storage in Kimchi fridge (−1.8 o C) for 67 days. Pesticide residues in young Chinese cabbageswere removed by up to 31~52% through brining and washing, 57~74% through seasoning with ingredients,61~76% through 14 hours storage at room temperature, and 70~82% through storage in Kimchi fridge.Pesticide residues in young radishes were removed by up to 57~85% through seasoning with ingredients,59~86% through 17 hours storage at room temperature, and 74~91% through storage in Kimchi fridge. Itmeans that brining and washing process was more efficient than fermentation process.Key words Pesticide residue, Young Chinese cabbage, Young radish, Kimchi, Reduction 서론 농산물을 재배하는 과정 중에 발생하는 병해충의 방제를위해 살포되는 농약은 농산물의 조리 과정을 통해 잔류량이변화될 수 있다. 다양한 조리 방법 중에서 세척(Krol 등, 2000;Guardia-Rubio 등, 2007; Liang 등, 2012) 및 껍질 벗기기(Awasthi, 1993; Hegazy 등, 1988) 등은 대표적인 잔류농약을 줄이는 조리 방법이다. 그러나 건조(Athanasopoulos 등,2005; Cabras 등, 2005; 남 등, 2007) 또는 끓이기(Bonnechere등, 2012; Elkins 등, 1972; Chavarri 등, 2005; Elkins 등,1989) 등의 조리 방법은 가열에 의해 수분이 감소되므로 농약의성질에따라 잔류농도가 감소되거나 증가한다. 발효과정은 효소가 단백질을 아미노산과 저분자량의 펩타이드로바꾸는 과정으로써(Pardez-Lopez 등, 1991) 발효과정을 통해 잔류농약의 농도가 줄어든다고 알려져 있다(Banna와Kawar, 1982; Abou-Arab, 2002; Ruediger 등, 2005).김치는 우리나라 고유의 대표적인 발효식품으로서 다양한재료에서 유래한 성분과 유산균 및 그 발효 성분으로 인해서 항암 효과, 소화 및 강장 효과, 항당뇨 효과, 성인병 예방효과 등의 기능을 가진 우수한 식품으로 알려져 있다(Park등 2012; Choi 등 2013). 김치 제조에 의한 잔류농약의 변화 연구는 통배추를 이용한 배추김치와 무 김치에 대해 이루어진바 있다(윤 등, 1989; 박 등, 2002; 황 등, 2011). 그러나 하절기에 비닐하우스에서 재배되는 얼갈이 배추와 열무의 경우 재배조건상 병해충 발생이 동절기 배추보다 더 많아 이를 방제하기 위한 농약의 살포가 더 필요하며 비표면

The objective of this study was to investigate the exposure assessment of Korean consumers toedifenphos and tricyclazole in cattle product fed the rice straw, using a probabilistic approach. We usedtricyclazole and edifenphos residue data in rice straw reported by National Academy of Agricultural Science(NAAS) for the 1998, 1999, 2001 and 2010 monitoring study and National Agricultural Products QualityManagement Service (NAQS) for 2009 monitoring study. The mean exposures of edifenphos and tricyclazole forall of Korean consumers were 0.027% and 0.0006% of ADI and 99% th percentile exposures were 0.034% and0.0007% of ADI respectively. The group of 1~6 years old consumers has the lowest exposure of edifenphos andtricyclazole. The group of 19~29 years old consumers has the highest exposure of edifenphos and tricyclazole.Key words Pesticide residue, Rice straw feed, Cattle by-product, Exposure assessment, Probabilistic approach 서론 볏짚은 우리나라에서 이용되는 가축 조사료의 40~50%를차지하는 작물로 매년 2백만 톤 안팍의 볏짚이 사료용으로이용되고 있다(MAFF, 2010). 볏짚은 쌀을 생산하는 과정에서 나오는 일종의 부산물로 벼의 병해충 방제를 위하여 사용한 농약이 볏짚에 잔류할 수 있다. WHO/FAO에서는1989년부터 식품 중 잔류농약의 오염평가 시 위해성평가기법을 도입하여 노출에 대한 안전성 여부를 판단하고 있다(FAO/WHO, 1997). 국내에서도 이러한 위해성평가기법을도입하여 식품 섭취에 의한 농약의 노출평가들이 보고되고있는데, 대부분이 농산물 섭취에 대한 평가이다(Do 등,2013; Paik 등, 2010). 사료에 대한 평가는 권 등(2000)이 볏짚의 잔류농약 모니터링결과를 농약의 일일섭취허용량과 대비하여 평가한 사례가 있으나 이 경우 볏짚을 섭취하는 소(400 kg)를 대상으로 평가한 것으로 실제 사람이 볏짚을 섭취한 소의 식육을 섭취할 경우에 대한 평가는 이루어진바없다. 농약의 인체에 대한 위해성평가는 해당 농약의 독성자료와 노출자료를 고려하여 유해물질의 유해영향 발생확률을 계산함으로써 평가하는 방법이다(Henry, 1997). 이러한위해성평가는 노출량, 섭취량, 체중 등의 변수를 단일 값만이용하여 평가하는 확정론적 접근법과 모든 변수들을 분포측면에서 고려하여 평가하는 확률적 접근법이 있다. 확정론적 접근법은 평가방법이 간단하고 이해가 쉽다는 이점 때문에 노출수준을 확인하는 일차적인 접근으로 주로 사용되고

Imidacloprid is a systemic insecticide which act as an insect neurotoxin. It used for control of pest such as aphids and other sucking insects in fruits and vegetables. Systemic pesticides move inside a crop following absorption by the plant, and these were converted into a variety of metabolites. Sometimes these metabolites make a problem about safety of agricultural products. So a simultaneous determination method of pesticide and its metabolites is needed, to monitor their presence in agricultural product and study on the fate of pesticide in a plant. This study's aim is to investigate simultaneous analysis method of imidacloprid and its metabolites, imidacloprid guanidine, imidacloprid olefin, imidacloprid urea, and 6-chloronicotinic acid in red pepper using QuEChERS method and LC-MS/MS systems. QuEChERS method was modifed beacuase MgSO salts decreased the recoveries of 6-chloronicotinic acid in extraction procedure. Imidacloprid and its metabolites were extracted by acetonitrile with 1% glacial acetic acid and the extracts were purified through QuEChERS with primary secondary amine (PSA) and C and 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 0.999. Recovery studies were carried out on spiked pepper blank sample at four concentration levels (0.01, 0.04 and 0.1, 0.4 mg/kg). The average recoveries of imidacloprid and its metabolites were in the range of 70~120% with < 20% RSD. This result indicated that the method using QuEChERS and LC-MS/MS was suitable for the simultaneous determination of imidacloprid and its metabolites in red pepper.

Pesticides were sprayed on perilla leaf and leafy lettuce in a greenhouse and the reduction rate ofpesticide residues on each vegetable by washing were tested. The reduction rate of pesticide residues bywashing for 30 sec~3 min on perilla leaf were 3~63% in tap water, 2~58% in salt water, 6~74% in green teawater, and 8~86% in detergent solution. The detergent solution only showed significant difference inreduction rates compared to the tab water washing. Considering reduction effects of the washing duration, itwas showed that the reduction rates were a pattern of inclining as the duration of washing process increased,but there was no significant difference in the reduction rates except the reduction rates between washing inthe detergent solution for 1 min and 3 min. Comparing washing in flowing tab water and in stagnant tabwater with leafy lettuce, the reduction rate by one time washing were 8~68% in flowing tab water and7~64% in stagnant tab water. The water and the time used in this experiment were 17.5 L, 2.9 min withflowing tab water and 4 L, 1 min with stagnant tab water. The reduction rate by 3 times washing in stagnanttab water were 16.5~76.6%, and the water and the time used were 12 L, 3 min. Therefore, when the waterand the time used to wash vegetables were considered, washing two or three times in stagnant tab watercould be more effective than washing one time in flowing tab water.Key words Pesticide residue, Leafy vegetable, Washing, Reduction

In analyzing pesticide residue, LLE (liquid liquid extraction) is generally applied as one of the existing methods, but needed quite a lot of organic solvents and analytical apparatuses for the sample pre-treatment. In addition to its long analysis time and complex analytical processes, it is required to develop a more rapid and efficient method at present. In order to establish an economic and simple pesticide residue analytical method, this study carried out a comparative experiment on the existing analytical method with a new sample pre-treatment method named QuEChERS (quick, easy, cheap, effective, rugged and safe), which extracts and refines pesticide components by directly adding solid powder into the sample. Both the two analytical methods showed favorable values of correlation coefficient ( > 0.99) of calibration curves. In terms of the detection limit (identification limit), imidacloprid showed 0.02 mg/kg, while the rest of pesticides showed a level around 0.05 mg/kg. The results of this experiment revealed that the recovery of LLE was 92.8-100.9% and the RSD was below 2.5%. On the other hand, the recovery of QuEChERS was 92.2-101.6% and RSD was below 1.9%. As a result of comparing the amount of pesticide residue by the time between the two analytical methods by using Paired t-Test, there was no significant difference between the two analytical methods as the p-value ranged from 0.3148-0.9890. Considering the results of the two methods, the QuEChERS method had similar recovery, compared to the analytical method using the existing LLE, and the analytical time was shortened by about one fourth of that of the existing method. Moreover, since it excludes the use of harmful organic solvents like dichloromethane during the process of extraction, thus leading to protecting experimenters health and remarkably reducing the amount of disused solvents, it is judged as an echo-friendly and economic analytical method.

BACKGROUND: This study was conducted to develop analytical method for picoxystrobin in agricultural commodities using GC/ECD and GC/MS. METHODS AND RESULTS: Each steps of analytical method were optimized for determining picoxystrobin residues in various agricultural commodities. The developed methods include acetone extraction, n-hexane/saline water partition and florisil column chromatography for analysis of all samples (apple, potato, green pepper, hulled rice and soybean), and in addition to these steps, solid phase extraction (SPE) was used for analysis of green pepper and n-hexane/acetonitrile partition was used for analysis of hulled rice and soybean. The instrumental conditions were tested for quantitation in GC/ECD and for confirmation in GC/MS. Recovery was in the range of 86~109% with RSD 10.2% and the quantitation limits (LOQ) of method were 0.025 mg/kg in all agricultural commodities. CONCLUSION: The result showed that the developed method can be used to determine picoxystrobin residue in agricultural commodities.

Association of official agricultural chemists official method was adapted and used to develop analytical method for determination of 76 pesticides residues in persimmon, grape, and pear by concurrent use of liquid chromatography-tandem mass spectrometry. Despite few exceptions in particular matrix, two fortified spiking (100 and 400 ppb) in three matrices gave satisfactory results in terms of accuracy, repeatability, precision, and linearity. Method detection limits (MDLs) were determined using five low spiking and eight replicate samples. MDLs were calculated by multiplying the standard deviation with student t-value 2.998 for n-1 (7) degree of freedom at 99% confident level. limit of quantification were obtained by multiplying standard deviation with 10. Experimental results indicate grape was the most problematic matrix among tested fruits and persimmon the least. Etoxazole is the most problematic pesticide and not applicable in this method. Developed method was successfully applied for the determination of residual pesticides in blindincurred samples.

This article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography (GC and LC) coupled to mass spectrometry (MS) for detection. The sample preparation approach is known as QuEChERS, which stands for "quick, easy, cheap, effective, rugged and safe". The three compared versions were based on the original unbuffered method, which was first published in 2003, and two interlaboratory validated versions: AOAC Official Method 2007.01, which uses acetate buffering, and European Committee for Standardization (CEN) Standard Method EN 15662, which calls for citrate buffering. LC-MS/MS and GC-MS analyses using each method were tested from 50 to 1000ng/g in apple-blueberry sauce, peas and limes spiked with 32 representative pesticides. As expected, the results were excellent (overall average of 98% recoveries with 10% RSD) using all 3 versions, except the unbuffered method gave somewhat lower recoveries for the few pH-dependent pesticides. The different methods worked equally well for all matrices tested with equivalent amounts of matrix co-extractives measured, matrix effects on quantification and chemical noise from matrix in the chromatographic backgrounds. The acetate-buffered version gave higher and more consistent recoveries for pymetrozine than the other versions in all 3 matrices and for thiabendazole in limes. None of the versions consistently worked well for chlorothalonil, folpet or tolylfluanid in peas, but the acetate-buffered method gave better results for screening of those pesticides. Also, due to the recent shortage in acetonitrile (MeCN), ethyl acetate (EtOAc) was evaluated as a substitute solvent in the acetate-buffered QuEChERS version, but it generally led to less clean extracts and lower recoveries of pymetrozine, thiabendazole, acephate, methamidophos, omethoate and dimethoate. In summary, the acetate-buffered version of QuEChERS using MeCN exhibited advantages compared to the other tested methods in the study.

In April of 2003, the gray mold disease caused by Botrytis cinerea was occured in zinnia seedlings grown in greenhouse at Gyeongsangnam-do Agricultural Research and Extension Services, and farmer`s nursery. The symptoms of infected plants were started with water-soaking lesions in flower bud, leaves and stems. The lesions gradually expanded and infected plants became withered and discolored to gray or dark from the tip. The conidia and mycelia of the pathogen were appeared on flowers, leaves and stem. The conidia were gray, 1-celled, mostly ellipsoid or ovoid in shape and were 516 48 in size. Conidiophores were 1228 in size. The pathogenic fungi formed sclerotia abundantly on potato dextrose agar. The optimum temperature for sclerotial formation was . Pathogenicity of the causal organism was proved according to Koch`s postulate. The causal organism was identified as Botrytis cinerea Persoon: Fries based on mycological characteristics. This is the first report on gray mold of Zinnia elegans caused by Botrytis cinerea in Korea.

In April of 2003 to 2004, the gray mold disease caused by Botrytis cinerea on Hypericum ascyron was occurred in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services, at Hamyang-gun in Korea. The disease symptoms were started with water-soaking lesions in stem and the infected plants became withered, discolored and died. The conidia and mycelia of the pathogen appeared on stems of infected plants. The conidia were 1-celled and mostly ellipsoid or ovoid in shape and their color was light gray. The size of conidia was and that of conidiophores was respectively. The pathogen formed sclerotia abundantly on potato-dextrose agar. The optimum temperature for sclerotial formation was . Pathogenicity of the causal organism was proved according to Koch`s postulate. The causal organism was identified as Botrytis cinerea based on mycological characteristics. This is the first report on gray mold of H. ascyron caused by B. cinerea in Korea.

A new polymeric Fe(II) chloride complex, [FeCl2(OPMe3)]∞ (1), has been synthesized from the reaction of stoichiometric quantities of FeCl3, Fe and OPMe3 (2:1:3) in THF. Use of a 2:1:6 ratio in the above reaction gives instead the mononuclear complex FeCl2(OPMe3)2 (2). The structure of the polymer consists of infinite chains of FeCl2(OPMe3) units, where each Fe atom is linked by four bridging chlorine atoms to two other Fe atoms. The arrangement of the four chlorine atoms and one OPMe3 molecule around the iron atom results in a trigonal bipyramidal coordination geometry. Complex 2 has tetrahedral geometry. The magnitudes of the magnetic moments for 1 and 2 at room temperature are 4.90 and 5.51 BM, respectively, indicative of high spin Fe2+. In 1, two different Fe…Fe distances 3.560(0) and 3.688(0) A alternate along the chain, the FeCl bond distances are in the range 2.35–2.60 A, the FeO distance is 1.954(2) A and the PO distance is 1.513(2) A. In 2, the FeCl distances average to 2.291(4) A, the average FeO and PO distances are 1.994(2) and 1.504(1) A, respectively. Crystallographic data: 1, monoclinic, space group P21/n, a=6.810(2), b=12.943(5), c=9.645(2) A, β=100.224(2)°, V=836.6(11) A3, Z=4, R=O.041 (Rw=0.058) for 101 parameters and 1665 unique data having Fo2>3σ(Fo2). 2, orthorhombic, space group P212121, a=11.270(3), b=12.011(2), c=10.811(2) A, V=1463.5(5) A3, Z=4, R=0.052 (Rw=0.064) for 142 parameters and 1356 unique data having Fo2>3σ(Fo2).

A new polynuclear compound of Fe(II) chloride with oxygen donor ligands has been isolated as a colorless crystalline solid, Fe4Cl8(THF)6 (1), by the reaction of FeCl3 and Fe in THF. 1 consists of centrosymmetric, tetranuclear molecules with two different types of Fe atoms, two (Fe(1) and Fe(1)′) in trigonal bipyramidal environments and the others (Fe(2) and Fe(2)′) in octahedral environments. Each trigonal bipyramidally coordinated iron atom is linked through doubly- and triply-shared chlorine atoms to an iron atom in an octahedral environment. The magnetic moment of 1, per iron atom, at room temperature is 5.40 BM, which is a reasonable value for high spin Fe2+. The Fe…Fe distances are 3.656(1) and 3.750(1) A for Fe(1)…Fe(2) and Fe(2)…Fe(2)′, respectively. The order of FeCl distances, Fe(μ3-Cl)>Fe(μ2-Cl)>FeClt is as expected. The FeClt distance is 2.244(1) ]A, the Fe(μ2-Cl) distances are 2.355(1)–2.488(2) A and the Fe(μ3-Cl) distances are 2.506(1)–2.737(1) A. The average FeO distance is 2.135(9) A. Crystallographic data: 1, triclinic, space group P 1 , a = 10.607(2), b = 10.993(3), c = 10.038(2) A, α = 111.84(3)°, β = 98.28(3)°, γ = 63.18(3) °, V = 969.2(6) A3, Z = 1, R = 0.048 (Rw = 0.069) for 188 parameters and 2616 unique data having Fo2>3σ(Fo2).

Leung and colleagues have revealed a five-dimensional structure of social axioms across individuals from five cultural groups. The present research was designed to reveal the culture level factor structure of social axioms and its correlates across 41 nations. An ecological factor analysis on the 60 items of the Social Axioms Survey extracted two factors: Dynamic Externality correlates with value measures tapping collectivism, hierarchy, and conservatism and with national indices indicative of lower social development. Societal Cynicism is less strongly and broadly correlated with previous values measures or other national indices and seems to define a novel cultural syndrome. Its national correlates suggest that it taps the cognitive component of a cultural constellation labeled maleficence, a cultural syndrome associated with a general mistrust of social systems and other people. Discussion focused on the meaning of these national level factors of beliefs and on their relationships with individual level factors of belief derived from the same data set., (undefined)

[Fe(Cl) 3 (C 4 H 8 O)] cristallise dans P2 1 /m avec a=6,288, b=10,360, c=7,477 A, β=106,05 o , Z=2; affinement jusqu'a R=0,051. Cette structure est de type tetraedrique, avec un miroir plan contenant l'un du chlore, le fer et l'oxygene du cycle furane. La distance Fe−Cl moyenne est de 2,154 A et les angles Cl−Fe−Cl et O−Fe−Cl sont respectivement de 112,6 et 106,7 o