살균제 Boscalid의 살포방법에 따른 인삼의 부위별 잔류 양상

황정인(Jeong-In Hwang),전영환(Young-Hwan Jeon),김효영(Hyo-Young Kim),김지환(Ji-Hwan Kim),안지운(Ji-Woon Ahn),김기수(Ki-Su Kim),유용만(Yong-Man Yu),김장억(Jang-Eok Kim) 한국농약과학회 2011 농약과학회지 Vol.15 No.4

This study was conducted to identify the residue patterns of fungicide boscalid in ginseng cultivated for 4 or 6 years treated by various spraying methods. The pesticide was sprayed separately on ginseng according to safe use guideline, and the field was divided into three groups and they were traditional, soil and vinyl mulching applications. The maximum residue amounts of boscalid were 0.76 mg/kg in traditional application group, 0.69 mg/kg in soil application group, 0.62 mg/kg in vinyl mulching application group in the whole part of 4 years old ginseng, respectively. These residue levels in ginseng exceeded the maximum residue limit established by Korea Food & Drug Administration, which is 0.3 mg/kg.

전원된 외상성 뇌 손상환자에서 중증도에 따른 일상적인 반복CT의 유용성

황정인 ( Jeong In Hwang ),조진성 ( Jin Seong Cho ),이승철 ( Seung Chul Lee ),이정훈 ( Jeong Hun Lee ) 대한외상학회 2009 大韓外傷學會誌 Vol.22 No.2

Purpose: Patients with traumatic brain injury (TBI) were referred from other hospitals for further management. In addition, patients routinely underwent computed tomography examinations of the head (HCT) in the referral hospitals. The purpose of this study was to evaluate retrospectively the utility of routine HCT scans according to the severity of TBI. Methods: Patients with TBI referred to our hospital between December 2005 and July 2008 were included in this study. We investigated HCT findings, indications for repeat HCT examinations (routine versus a neurological change), and neurosurgical interventions. The head injury severity was divided into three categories according to the Glasgow Coma Scale (GCS) score, including mild, moderate, and severe TBI. The use of neurosurgical interventions between patients who underwent routine HCT scans and patients who underwent HCT scans for a neurological change were compared according to the severity of TBI. Results: A total of 81 patients met the entry criteria for this study. Among these patients, 67%(n=54) of the patients underwent HCT scans on a routine basis, whereas 33%(n=27) of the patients underwent HCT scans for a neurological change. A total of 21 patients showed signs of a worsening condition on the HCT scans. Neurosurgical intervention was required for 23(28.4%) patients. For patients who underwent routine HCT examinations, no patient with mild TBI underwent a neurosurgical intervention. However, one patient with moderate TBI and three(13%) patients with severe TBI underwent neurosurgical interventions. The kappa index, the level of agreement for HCT indications of intervention and referral reasons for intervention, was 0.65 for high hierarchy hospitals and 0.06 for low hierarchy hospitals. Conclusion: Routine serial HCT examinations in the referred hospitals would be useful for patients with severe head injury and for patients from low hierarchy hospitals where no emergency physicians or neurosurgeons are available. (J Korean Soc Traumatol 2009;22:134-41)

토양에 잔류된 살충제 Chlorpyrifos의 오이 흡수이행 및 분포 양상

황정인(Jeong-In Hwang),전상오(Sang-Oh Jeon),이상협(Sang-Hyeob Lee),이성은(Sung-Eun Lee),허장현(Jang-Hyun Hur),김권래(Kwon-Rae Kim),김장억(Jang-Eok Kim) 한국농약과학회 2014 농약과학회지 Vol.18 No.3

The transfer pattern of chlorpyrifos present in soil to cucumber plants were assessed and reported with plant growth, concentration dependency, and duration. Cucumber seedlings cultivated in a growth chamber for 30 days and a greenhouse for 120 days. Weight and length of cucumbers cultivated in the chamber increased with the increasing time, while the uptake of chlorpyrifos by cucumber increased a period from 0 to 15 days and decreased after 15 days. Uptake rates of chlorpyrifos into a cucumber plant were 1.0~1.3% to initial amounts treated with 20 and 40 mg/kg to soil. Most chlorpyrifos residues were detected in root, followed by stem and leaf. Results of the greenhouse test showed that chlorpyrifos amounts in cucumber fruits were present less than LOQ (0.02 mg/kg), and chlorpyrifos was mainly found in the root of the cucumber plant. Chlorpyrifos absorbed in a cucumber under greenhouse condition was smaller than that in chamber condition as 0.03~0.04%. Degradation patterns of chlorpyrifos in soils were similar during indoor and outdoor tests with half-lives of 25.8~73.0 days. These results may be useful for establishing the management strategy of residual pesticides in soil environment.

다공성 규조토 컬럼을 이용한 한약재 중 잔류농약 분석법 개선

황정인(Jeong-In Hwang),전영환(Young-Hwan Jeon),김효영(Hyo-Young Kim),김지환(Ji-Hwan Kim),안지운(Ji-Woon Ahn),석다롱(Da-Rong Seok),이윤정(Yoon-Jeong Lee),박주영(Ju-Young Park),김도훈(Do-Hoon Kim),김장억(Jang-Eok Kim) 한국농약과학회 2011 농약과학회지 Vol.15 No.2

The official analytical method of residue pesticides in herbal medicines by KFDA cannot be applied to all of the pesticides and herbal medicines because of various active materials in herbal medicines and various physicochemical properties of pesticides. Moreover, liquid-liquid partition uses harmful solvents such as methylene chloride and is consuming a lot of time and effort. In order to improve the problems, we have studied for the availability of the analytical method applying the macroporous diatomaceous earth (MDE) column instead of liquid-liquid partition to simultaneously analyze five pesticides in two dried herbal medicines The results showed that the recovery rates of acetamiprid and azoxystrobin in Astragalus root by GC/ECD ranged from 89.6 to 94.1%, from 86.8 to 94.4%, respectively, and those of bifenthrin, chlorfenapyr, chlorpyrifos in Cnidii Rhizoma by GC/MS ranged from 83.6 to 88.4%, from 77.4 to 83.8%, from 82.6 to 84.3%, respectively. Also, the coefficients of variation (CV) for triplication ranged from 0.5 to 1.7%. The results satisfied the criteria of residue pesticide analysis, setting 70~120% for the recovery rate and below 10% for the coefficient of variation. The improved methods are safer to residue pesticide analysts, faster and less laborious than the KFDA official method.

03 구두발표 : 구두발표(OA) - 농업환경 및 토양,수질 분야 ; OA-02 : 토성이 다른 토양 중 Endosulfan 이성질체의 잔류양상 예측

황정인 ( Jeong In Hwang ),전상오 ( Sang Oh Jeon ),이상협 ( Sang Hyeob Lee ),강민수 ( Min Su Kang ),정혜현 ( Hye Hyun Jung ),곽세연 ( Se Yeon Kwak ),이성은 ( Sung Eun Lee ),김장억 ( Jang Eok Kim ) 한국환경농학회 2015 한국환경농학회 학술대회집 Vol.2015 No.-

Pesticides persisted in soil environment may be subjected to the unexpected uptake by plant root. As these absorbed pesticides can result eventually in safety problems to agricultural products, it is required to predict the plant uptake extent of soil-persisting pesticides inadvance. One of the previous prediction methods is to assess the uptake extent using a mathematical model. When developing the plant uptake model of soil-persisting pesticides, adsorption and dissipation interactions between pesticides and soil may be parameters that play major roles in determining the uptake extent into plant. With considerations of parameters relative to these interactions, we developed a chemical-specific residue (CSR) model, Ce(t)=C0·(1/2)t/T/Kd, in order to predict the residual patterns of endosulfan isomers ( - and  -) in soils containing different organic matter contents. The adsorption (Kd) and dissipation (T) parameters were obtained from indoor experiments, and the applicability of CSR model was assessed by comparing between experimental measurements and modeled estimates. The Kd and T values were significantly varied depending on organic matter contents in the tested soils. For the low organic matter-containing soil, the Kd and T values of the  -isomer were 50.2 mL g-1 and 16 d, respectively; the values of the  -isomer were 54.4 mL g-1 and 231 d, respectively. On the other hand, for the high organic matter-containing soil, the Kd values were 377.4 mL g-1 for the  -isomer and 407.4 mL g-1 for the  -isomer, and the T values for the  - and  -isomers were 139 and 347 d, respectively. Using these parameter values, the modeled values were in good agreement with the measured values with standard errors of less than 23.5%. Therefore, the developed CSR model may be used as a tool for predicting the residual amount of endosulfan in soil.

토양잔류 농약의 식물흡수에 대한 모델예측 및 관리전략

황정인 ( Jeong-in Hwang ),김장억 ( Jang-eok Kim ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

재배환경 중 작물에 살포된 농약은 직접 또는 간접적으로 토양에 떨어져 잔류할 수 있고, 잔류된 농약의 일부는 작물체로 흡수되어 잔류문제를 야기할 수 있다. 하지만 토양 중 잔류농약의 기준설정과 관리방안에 대한 연구는 여전히 미미한 실정이다. 본 연구에서는 토양잔류 농약의 식물흡수예측 모델식을 개발하고 예측된 결과를 이용하여 토양 중 잔류농약에 대한 관리기준을 제시하고자 하였다. 개발된 모델식의 적용성은 유기염소계 살충제 엔도설판의 α 및 β 이성질체를 대상으로 상추에 대한 흡수이행 실험을 실시하여 얻은 실험값을 모델식을 이용한 예측값과 통계적으로 비교함으로써 평가되었다. 그 결과, 개발된 모델식에 대한 적용성은 β 이성질체에 대해 39.2%의 편차를 보이며 양호하였으나 α 이성질체에 대해서는 176.3%의 상당한 편차를 보이며 낮았다. 또 한 예측된 결과로부터 제시된 상추재배 토양 중 엔도설판의 관리기준은 1.6 mg kg-1이었으나, 토양 중 생성되는 주요 대사체인 엔도설판 sulfate를 고려하여 더 낮은 농도에서 기준이 설정되어야 했다. 한편, 토양 중 잔류하는 엔도설판의 근원적인 제거를 위해 zero-valent iron (ZVI)과 ascorbic acid (AA)를 이용한 화학적인 토양복원기술도 개발하였다. 수중 분해시험을 통해 가장 효과적인 엔도설판 분해시스템(AA/ZVI/H2O2 시스템)을 조사하고 이 시스템을 토양에 적용한 결과, 엔도설판의 분해율은 α 이성질체에 대해 64.0%, β 이성질체에 대해 66.2%로 나타났으며 분해 반감기 또 한 2.7~2.8일으로 상당히 빨랐다. 전체적으로 이 연구에서 개발된 식물흡수예측 모델식과 화학적인 토양복원기술은 토양잔류 농약의 식물흡수에 대한 사전관리 방안으로 고려될 수 있었다. Most of pesticides deposited on soils either after direct or foliar spraying could be persisted in the soil, and a portion of their residues may result in the plant uptake via root. Although the plant uptake of pesticides from soil can contribute to safety problems for final agricultural products, there are no assessment tools and standards for managing the pesticide residues in soils. In this study, we developed a mathematical model for predicting theoretically the plant uptake of pesticide residues from soil and suggested a management standard for pesticide residue in soil based on the modeled results. An accuracy of the developed model was assessed by statistically comparing the modeled values with the values measured in the uptake experiments of α- and β-isomers of endosulfan (ED) by lettuce grown on ED-treated soils. As a result, the developed model was available for β-ED with the deviation of 39.2%, but not for α-ED with high deviation of 176.3%. Based on the modeled values, the management standard for ED in lettuce-cultivating soil was proposed at concentration of 1.6 mg kg-1. However, this standard concentration should be established lower than 1.6 mg kg-1 due to the consideration of toxic metabolite ED-sulfate produced with the degradation of isomers. On the other hand, we developed a chemical remediation technology to remove fundamentally the ED isomers from soil. Through aqueous degradation experiment, we found that the use of combined reagents of zero-valent iron (ZVI), ascorbic acid (AA), and H2O2 was the most effective system for the degradation of ED isomers in water, and this system was applied to remove the isomers in soil. By the use of AA/ZVI/H2O2 system, the degradation rates of α- and β-ED in soil were 64.0 and 66.2%, respectively, and their degradation half-lives were short at 2.7~2.8 d. In conclusion, overall results in this study suggest that technologies such as theoretical model prediction and chemical soil remediation could be used as advanced management strategies to prevent previously the undesirable plant uptake of pesticide residues from soil.

토양잔류 농약의 무 흡수양상 및 토양 안전관리기준 설정

황정인 ( Jeong-in Hwang ),곽세연 ( Se-yeon Kwak ),이상협 ( Sang-hyeob Lee ),강민수 ( Min-su Kang ),류준상 ( Jun-sang Ryu ),강자군 ( Ja-gun Kang ),정혜현 ( Hye-hyeon Jung ),홍성현 ( Sung-hyeon Hong ),김장억 ( Jang-eok Kim ) 한국환경농학회 2016 한국환경농학회지 Vol.35 No.4

BACKGROUND: Uptake patterns of α-, β-isomers and sulfate metabolite of endosulfan (ED) by radishes grown in treated soils with ED concentrations of 2 and 10 mg/kg were investigated to establish soil management guidelines for ensuring the safety of radishes from ED residues. METHODS AND RESULTS: All samples of soils and radish plants separated into shoot and root parts were analyzed for ED residues using a gas-chromatography mass spectrophotometer, and the results were used to calculate the bioconcentration factor (BCF), indicating the ratio of ED concentrations between radishes and soils. During the experimental period, uptake and distribution rates of ED-sulfate in radishes were the highest, followed by α- and β-ED. The BCF values to initial ED concentrations in soils were greater for root parts (0.0077 to 0.2345) than for shoot parts (0.0002 to 0.0429) and used to obtain regression equations by time. Long-term BCFs estimated by the obtained equations (R² of 0.86 to 1.00) were evaluated with the maximum residue limit (0.1 mg/kg) of ED for radishes, in order to suggest safe management guidelines of ED for radish-cultivating soils. CONCLUSION: Suggested guidelines showed the significant dependency on duration for radish cultivation and exposed concentration of ED in soil.

구두발표(OC)-농업화학 및 생태,식품분야 : OC-01 ; 토양잔류 Endosulfan의 오이유묘 중 흡수이행량 조사

황정인 ( Jeong In Hwang ),전영환 ( Young Hwan Jeon ),전상오 ( Sang Oh Jeon ),이상협 ( Sang Hyeob Lee ),이성은 ( Sung Eun Lee ),김장억 ( Jang Eok Kim ) 한국환경농학회 2014 한국환경농학회 학술대회집 Vol.2014 No.-

Distribution of organochlorine insecticide, endosulfan isomers (α- and β-) and their metabolite (-sulfate) absorbed from soil into cucumber plug seedling was investigated in relation with passed time, treated amount, and plant growth. Cucumber plants were sampled with corresponding soils at 15 and 30 days after transplanting, and their weight and length were measured in each part such as root, stem, leaf, and fruit. The length and weight of plant parts showed increasing tendencies during the experimental period. The residual amounts of endosulfan isomers in soil were continuously declined, while endosulfan-sulfate was slightly produced. The amounts of endosulfan isomers absorbed into plants were increased by 10 days; however, after the time, the amounts were insignificantly decreased. The absorbed amounts of endosulfan isomers from soil were ranged from 0.4 % to 1.1 %, and 3.4∼4.6 % of the produced metabolite were subjected to plant uptake. Distribution of endosulfan (α-, β-, and -sulfate) was the greatest in root throughout the experimental period, whereas that in stem, leaf, and fruit was varied with the passed time. The residual amount of β-endosulfan in a cucumber plant was dominantly great, followed by α-endosulfan and endosulfan-sulfate. Consequently, it is most likely that endosulfan isomers and their metabolite could be absorbed by cucumber root and be transferred to subsequent parts such as stem, leaf, and fruit.

구두 발표 : 구두발표(OC) - 농업화학 및 생태,식품분야 ; 토양 유기물 함량에 따른 유기염소계 살충제 Endosulfan의 흡착 특성

황정인 ( Jeong In Hwang ),전영환 ( Young Hwan Jeon ),김정민 ( Jung Min Kim ),석다롱 ( Da Rong Seok ),이은향 ( Eun Hyang Lee ),전상오 ( Sang Oh Jeon ),이성은 ( Sung Eun Lee ),김장억 ( Jang Eok Kim ) 한국환경농학회 2013 한국환경농학회 학술대회집 Vol.2013 No.-

A study on fate and behavior of endosulfan, which is an organochlorine insecticide detected mainly in Korean soil, is important due to its toxicity and persistence in soil environment. To estimate isotherms for the adsorption of endosulfan isomers (α-, β-) and their metabolite (-sulfate) in soil, their adsorption amounts were investigated in various soils containing different organic matter contents. The tested soils were collected at Ansim and Gunwi, and some of them were prepared as organic matter-removed (OMR) samples using H2O2. As time-dependent adsorbed amounts of endosulfan reached to their equilibrium after 6 h in Ansim, Gunwi and OMR Ansim soils, OMR Gunwi soil did not adsorb the pesticide within 24 h. The adsorption isotherms of endosulfan isomers and their metabolite fitted to Freundlich adsorption isotherms for three equilibrated soil samples. The correlation coefficients (R2) of the isotherms were greater than 0.964. Freundlich adsorption coefficient (Kf) ranged from 8.66 to 19.20 for α-endosulfan, from 7.08 to 20.49 for β-endosulfan and from 8.62 to 17.98 for endosulfan-sulfate, respectively. The difference of Kf values of endosulfan indicated that the adsorption amount of endosulfan was dependent on the contents of organic matter. Therefore, the behavior of endosulfan in soil environment is definitely affected by the amount of organic matters in soil.

농식품 환경 분야(PF) : PF-13 ; 두 지역에서 재배된 배 중 Fenitrothion과 Myclobutanil의 잔류 패턴

전상오 ( Sang Oh Jeon ),황정인 ( Jeong In Hwang ),전영환 ( Young Hwan Jeon ),이상협 ( Sang Hyup Lee ),김장억 ( Jang Eok Kim ) 한국환경농학회 2014 한국환경농학회 학술대회집 Vol.2014 No.-

It is important to investigate biological half-lives (t1/2) of pesticides for predicting their residual amounts at harvest time. In this study, dissipation patterns of fenitrothion and myclobutanil were studied in two pear orchards, Yeongcheon (YC) and Gyungju (GJ), and pre-harvest residue limits (PHRLs) for the pesticides in pears were calculated using their half-lives. The residual amount of fenitrothion in YC pear at the harvest time slightly exceeded its maximum residue limits (MRLs) which is 0.20 mg/kg, whereas that in GJ pear was below MRLs. In case of myclobutanil, the residual amounts were below MRLs in pears of both regions. The dissipation constants of fenitrothion in YC and GJ pears were 0.055 (t1/2 = 12.6 days) and 0.040 (t1/2 = 17.3 days), respectively, and those of myclobutanil were 0.025 (t1/2 = 12.6 days) and 0.097 (t1/2 = 17.3 days), respectively. According to the calculated PHRLs, if the residual amounts of fenitrothion and myclobutanil in pears were 0.48~0.67 mg/kg and 1.20~ 1.69 mg/kg, respectively, at 10 days prior to the harvest, their residue amounts in pears at the harvest time would be below the MRLs.