Import Tolerance 설정을 위한 꽃받침포함 딸기 중 Flonicamid와 대사산물의 잔류성

오영곤 ( Young Goun Oh ),정윤수 ( Yun-Su Jeong ),이동기 ( Dong-gi Lee ),설재웅 ( Jae Ung Seol ),김지명 ( Ji Myung Kim ),이승현 ( Seung-hyun Lee ),조일규 ( Il Kyu Cho ) 한국환경농학회 2021 한국환경농학회 학술대회집 Vol.2021 No.-

Pre-harvest interval and decline pattern of flonicamid, TFNG and TFNA were determined in strawberry with calyx using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The study was carried out to propose import tolerance for export promotion of strawberry to Taiwan by using OECD maximum residue limit (MRL) calculator. The residue field trials for flonicamid (50%, SG, insecticide) were carried out as decline tests in the three independent sites to cultivate strawberry. The flonicamid (50%, SG) of test substance was diluted 10,000 times and the 0.00764 kg a.i./10 a of flonicamid 50% SG was applied for the sites two times at 7-day intervals. Sampling was carried out 0, 1, 3, 5, 7, 14, 21, 28, 35 and 45 days after the final application of flonicamid (50%, SG), and untreated control samples were collected prior to the sampling of treated plots. The residual amount of flonicamid included with TFNG and TFNA presented 0.06∼1.40 mg/kg in site 1 (Sacheon), 0.06∼0.82 mg/kg in site 2 (Gokseong) and 0.18∼1.15 mg/kg in site 3 (Nonsan), respectively, in the strawberry with calyx for three decline test. In cThe import tolerance of flonicamid for strawberry with calyx may be recommended at 3.0 mg/kg in Taiwan by the OECD MRL calculator.

꽃받침포함 딸기 중 Thiacloprid와 Flufenoxuron의 잔류연구

정윤수 ( Yun-Su Jeong ),오영곤 ( Young Goun Oh ),이동기 ( Dong-gi Lee ),설재웅 ( Jae Ung Seol ),김지명 ( Ji Myung Kim ),김원일 ( Won-il Kim ),조일규 ( Il Kyu Cho ) 한국환경농학회 2021 한국환경농학회 학술대회집 Vol.2021 No.-

The persistence pattern of thiacloprid and flufenoxuron were determined in strawberry with calyx using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The study was carried out to propose import tolerance using OECD maximum residue limit (MRL) calculator for export promotion of strawberry with calyx to Taiwan. The residue trials of thiacloprid (10% SC) and flufenoxuron (5% DC) were conducted as decline tests at three independent sites for strawberry. Excellent linearity observed for all of the analytes with determination coefficient (R²)≥0.99. The both LOQ (limit of quantification) of thiacloprid and flufenoxuron were 0.01 mg/kg in strawberry. The recovery rate of thiacloprid presented 76.8∼ 101.4 % in site 1, 83.9 ∼108.6 % in site 2 and 76.1∼101.9 % in site 3, respectively. The recovery rate of flufenoxuron showed 80.2∼98.7 % in site 1, 99.8∼117.4 % in site 2 and 81.1∼ 91.7 % in site 3, respectively. The residual amount of thiacloprid in the strawberry for three decline test were found in the range of 0.44 to 1.11 mg/kg in site 1 (Sacheon), 0.17 to 0.38 mg/kg in site 2 (Gokseong) and 0.19 to 0.39 mg/kg in site 3 (Nonsan). The residual amount of flufenoxuron in the strawberry for three decline test were found in the range of 0.34 to 1.50 mg/kg in site 1 (Sacheon), 0.20 to 0.48 mg/kg in site 2 (Gokseong) and 0.28 to 0.58 mg/kg in site 3 (Nonsan). In conclusion, the both import tolerance for thiacloprid and flufenoxuron in strawberry with calyx were proposed to 2.0 mg/kg in Taiwan.

Diquat Dibromide 토양광분해성

조일규 ( Il Kyu Cho ),설재웅 ( Jae Ung Seol ),오영곤 ( Young Goun Oh ),김지명 ( Ji Myung Kim ),서민경 ( Min Kyeong Shu ),윤중식 ( Jung-sik Yoon ) 한국환경농학회 2018 한국환경농학회 학술대회집 Vol.2018 No.-

Diquat dibromide (1,1'-ethylene-2,2'-bipyridyldiylium dibromide) causes injury to only the parts of the plant to which it is applied. However, it may be fatal to humans if swallowed and inhaled even though it is used to desiccate potato vines and seed crops. Photodegradation of diquat dibromide can be an important factor to remove it in environment. The aim of this study is to understand photodegradation pattern of diquat dibromide in the soils. The photodegradation trial has been performed in compliance with the method (OPPTS 835.2410 photodegradation on soil EPA fate, transport and transformation test guidelines) with the upland soils of Yongin and Chungju in Korea. This study indicated that the main photolytic-metabolites of TOPPS and diquat monopyridone were detected below the detection of limit (0.01 mg/kg) by using the LC-TriQ-MS/MS under the 300 nm of artificial light condition. The half-life (DT50) of diquat dibromide during the soil photolysis showed 43.9 and 22.4 days at the Yongin-upland soil that was applied with 35 mg/kg and 90 mg/kg of diquat dibromide, repectively. On the other hand, the DT50 of diquat dibromode in the Chungju-upland soil were 23.3 and 25.3 days at the 35 mg/kg and the 90 mg/kg of diquat dibromide-treated soil, respectively.

사토양와 양토 재배 후작물 중 Diquat dibromide의 약해와 전이

조일규 ( Il Kyu Cho ),양해룡 ( Hae-Ryong Yang ),설재웅 ( Jae Ung Seol ),오영곤 ( Young Goun Oh ),이동기 ( Dong-gi Lee ),김지명 ( Ji Myung Kim ),김원일 ( Won-il Kim ) 한국환경농학회 2021 한국환경농학회 학술대회집 Vol.2021 No.-

Diquat dibromide (1,1’-ethylene-2,2’-bipyridyldiylium dibromide) is known as a fast-acting nonselective herbicide and plant growth regulator. This agrochemical causes injury to the parts of the plant to which it is applied. However, it may be fatal to humans if swallowed and inhaled even though it is used to desiccate potato vines and seed crops. This study was carried out to understand the safety of the following crops such as pepper, radish, lettuce and corn through phytotoxicity and residual evaluation in the unintentional contamination of the higher residual diquat dibromide. The diquat dibromide was analyzed by using the LC-TriQ-MS/MS. The diquat dibromide was determined after 30 days of crop cultivation in soil which had been applied with 35 and 90 mg/kg of diquat dibromide. The diquat dibromide remained 26.3∼28.1 and 70.9∼75.8 mg/kg at the 35 mg/kg and 90 mg/kg of diquat dibromide-treated soil, respectively. This result indicated that diquat dibromide did not convert to other metabolites and resided mostly in the soil during crop cultivation even though it was partially decomposed. In addition, the diquat dibromide were found around 0.01 mg/kg and below the detection of limit (0.01 mg/kg) in the 47 day-elapsed pepper and radish as well as 30 day-elapsed lettuce and corn cultivating in sandy loam and loam soil which were treated with 90 mg/kg of diquat dibromide.

미생물제(Rhodococcus sp. 3-2) 처리에 따른 토양 중 카벤다짐의 분해효과

연제형 ( Jehyeong Yeon ),김현수 ( Hyeon-su Kim ),안재형 ( Jae-hyung Ahn ),한귀환 ( Gui Hwan Han ),오영곤 ( Young Goun Oh ),조일규 ( Il Kyu Cho ),박인철 ( In-cheol Park ) 한국환경농학회 2021 한국환경농학회지 Vol.40 No.4

BACKGROUND: The fungicide of benomyl, a benzimidazole group, has been commonly used for pesticides against fungal diseases in the world. However, benomyl is rapidly hydrolyzed in the environment after using to control plant diseases and has adverse effects by generating carbendazim, which is toxic to plants, humans, and the environment. METHODS AND RESULTS: In this study, the decomposition effect of carbendazim, a degradation product of benomyl was conducted in pot and field after making a prototype of benomyl-degrading microbial agent (BDMA). We found that the carbendazim-degrading microbial agent (CDMA) (10⁵, 10⁶, and 10⁷ cfu/g soil) decomposed carbendazim by 50% or more in all the treatments, compared to the untreated control in the pot tests after four weeks. The effect of 100% decomposition of carbendazim was observed at 7 days after treatment, when the prototype of BDMA was apllied at 10-folds dilution in the field. The decomposition effect at more than 60% and plant growth promoting effect were observed after 7 days of the treatment, compared with the untreated group in the second field experiment,treated with commercially available concentrations of 500-folds and 1,000-folds. CONCLUSION(S): These results might represent that the BDMA would decompose carbendazim effectively, a decomposition product of the fungicide benomyl, remaining in agricultural area, and it could be utilized practically by using a low dilution rate.