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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

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

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

A series of monitoring studies were carried out to evaluate the residue level of pesticides in different native soils from 1999 to 2006. The nation-wide collection of soil samples from paddy, greenhouse, upland and orchard, were analyzed by GLC (ECD or NPD) and GC/MS. The results obtained are summarized as follows; out of 14 pesticides detected from paddy soils in 1999, the highest residue level was 0.25 mg kg , and the frequency was 21.7% as butachlor, 20.0% as isoprothiolane, and 16.7% as iprobenfos. In 2003, 7 pesticides were detected and their frequencies were 0~36.0%; the frequency was 36.0% as isoprothiolane and 33.3% as oxadiazon. In the year 2000, 57 pesticides in the greenhouse soil samples were detected with the highest frequency of 65.3%. Of the pesticides detected, endosulfan and procymidone showed the frequency of 65.3 and 50.0%, respectively. In 2004, 19 pesticides were detected from greenhouse soils, and their frequencies and residue levels were decreased. Endosulfan and procymidone showed high detection frequencies and concentrations of 21.3 and 9.3% and 0.76 and 0.31 mg kg , respectively. In 2001, a total of 25 pesticides were detected through monitoring in 170 upland soils and the highest residue level was 2.24 mg kg . The detection frequencies showed the range of 0~53.5%. Especially, endosulfan showed the highest frequency of 53.5%. Residue levels and frequencies of pesticide in the year 2005 were almost the same compared with that of the year 2001. As a result of monitoring in 150 orchard soils in 2002, 26 pesticides were detected and the highest residue level was 1.43 mg kg . Of them, the frequency of endosulfan showed the highest as 45.3%. In 2006, 20 pesticides were detected in orchard soils. The frequency of total endosulfan was the highest as 5.3% but was lower than that of the year 2002.

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

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.

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 conducted for the establishment of the analytical method of pesticide residues in rice straw for 9 pesticides; etofenprox, tricyclazole, diazinon, edifenphos, propiconazole, carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran and for the monitoring of these pesticides in rice straw for livestock feed in Korea. These pesticides were classified into 4 groups according to analytical instrument condition. Group 1 (HPLC-UVD1) included tricyclazole and etofenprox while group 2 (HPLC-UVD2) included propiconazole and edifenphos. Group 3 (HPLC-FLD) included carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran. Group 4 (GC-NPD) included Diazinon. The dried rice straw samples were extracted with acetone and purified by liquid-liquid partition and solid phase extraction (SPE): Combination of Florisil SPE and amino-propyl SPE was used for group 1 and group 2, amino-propyl SPE for group 3, and Florisil SPE was for group 4. Recovery was in the ranged 70~110% and the limits of quantitation (LOQ) were lower than the half of maximum residue limits. Therefore this method was proved to be efficient for monitoring of these pesticides residue in rice straw. A total of 18 rice straw samples from 6 provinces in Korea in 2010 were analyzed using established method and, only 3-keto carbofuran was detected in one sample at concentration of 0.04 mg/kg. Key ward Rice straw, Pesticide residue, Analytical method, Monitoring

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