• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.359-364
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• 2005

Comparison of pesticide residue dissipation in/on cucurbitaceous fruit vegetables applied by foliar spraying under greenhouse was carried out to give information on crop grouping for assessment of pesticide risk. Even though the initial deposit of spayed pesticide on the target vegetables were somewhat different from the varieties, the dissipation patterns of the residues gave a similar tendency. In case sub-groupings of cucurbitaceous fruit vegetables are carefully arranged, the residue data among the vegetables are able to be taken for pre-harvest interval (PHI) settings or food safety assessment.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.354-358
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• 2005

The study was carried out to investigate dissipation pattern of pesticide residue in/on different varieties of lettuce applied with foliar spraying under greenhouse. The initial deposited amount of alpha-cypermethrin and imidacloprid in/on the crop was entirely corresponded with shape of the crop. Dissipation of deposited pesticide residue was supposed to be related with degradation by sunlight and wash off by watering rather than dilution effect by biomass increase. The crop grouping in leaf vegetables has to be carefully considered even in lettuce for dissipation pattern of pesticide residue; head type and leafy type.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.228-235
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• 2014

The residue levels of flonicamid and its metabolites, 4-(trifluoromethyl)nicotinic acid (TFNA) and N-4-(trifluoromethyl)nicotinoyl glycine (TFNG) in sweer pepper were investigated to examine the residual characteristics of analytes for 87 days after pesticide application. The pesticide was applied once at recommended dosage and double dosage by foliar sprays and the samples of fruits and leaves of sweet pepper were collected for each treatment. The residues of flonicamid in all of fruits and leaves decreased gradually over time, while the residue levels of TFNG metabolite exhibited tendency that increased for long periods and thereafter decreased. Total flonicamid residual concentrations containing metabolites residues in fruit samples increased consistently until 30 days post-application and higher residue levels than residues at 1 day post-application were detected from 30 day to 87 day after treatment. The residue pattern observed in fruit could be explained by the movement of TFNG from leaves to fruits of plant. Such residual characteristic was similarly found in samples treated both recommended dosage and double dosage.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.341-348
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• 2016

Residual patterns of fungicides fludioxonil and metconazole applied 2 or 3 times on wheat were investigated with consideration for their distribution rates in each compartment of wheat. Wheat samples collected at harvesting day were divided into three compartments such as grain, hull and straw, and the pesticide residue analysis was individually carried out to such compartments of wheat. The analytical methods of fungicide residues in wheat were acceptable, with recoveries of 84.3 to 113.3% and correlation coefficients of 0.1 to 4.7%. Due to the systemic characteristics, the residual amounts of metconazole in the grain part of wheat were greater as 0.13~0.17 mg/kg than those amounts (0.01-0.03 mg/kg) for fludioxonil. To absolute residue amounts of the fungicides in one wheat plant, their distribution rates in each compartment of wheat were the highest in straws (68.5-70.7%), followed by hulls (29.0-31.0%) and grains (0.2-0.8%).

• The Korean Journal of Pesticide Science
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• v.18 no.2
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• pp.61-68
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• 2014

Dissipation constants and half-lives of acaricides etoxazole and flufenoxuron in apples were calculated to establish their pre-harvest residue limits (PHRLs). The acaricides were sprayed on apples with single and triple doses based on safe use guidelines, and their residual patterns in the apple were interpreted using first order kinetics equation. The residual amounts of acaricides during the experimental period were below their maximum residue limits (MRL) for apple. The dissipation constants of acaricides in the apples were calculated at 0.0788 for etoxazole and 0.0319 for flufenoxuron corresponding to their biological half-lives; 8.8~21.7 days for etoxazole and 21.7~23.1 days for flufenoxuron. The PHRLs of acaricides in the apple showed the residual amounts of etoxazole and flufenoxuron at the harvesting date would be below their MRLs if their residual amounts were less than 0.87 and 0.88 mg/kg, respectively, at 7 days prior to harvesting the apples.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.231-236
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• 2002

We studied the residual patterns of two fungicides, dichlofluanid and iprodione, in cherry tomato greenhouse after applying with the recommended and double dose. Also, the degradation patterns during storage periods of up to ten days were compared between at room temperature (20$^{\circ}C$) and at cold temperature (4$^{\circ}C$). Removal rates of fungicides by washing with tap-water and detergent solution (0.1%, 0.2%) were measured. Half-lives of dichlofluanid and iprodione in greenhouse cherrytomato were 2.2$\sim$3.5 and 3.3$\sim$5.4 days, respectively. During the storage period, the residues were dissipated more slow. Removal rates were 62.8$\sim$80.3% by tap-water, 60.4$\sim$83.1% by 0.1% detergent solution, and 65.3$\sim$77.6% by 0.2% detergent solution. So, we can predict of terminal residues from cultivation period to marketing, storage and consuming.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.230-240
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• 2017

BACKGROUND: To evaluate residues of environmentally concerned pesticides in water system, this monitoring was conducted over three rivers. The residual characteristics and discharging condition of these residues on water system was investigated. METHODS AND RESULTS: Total twenty nine sampling sites were selected through main streams and branch streams of Keum, Mangyung and Dongjin rivers, and the water samples from them were regularly collected one month interval, especially biweekly from May to August in 2002. Of the pesticides monitored, six fungicides which include hexaconazole, isoprothiolane and iprobenfos were detected with frequencies of 0.3-50.9% and in their residue level of $0.1-4.7{\mu}g/L$. Sixteen insecticides which include nine organophosphoruses, three carbamates, endosulfan, cypermethrin, buprofezin and fipronil were detected with frequencies of 0.3-32.5% and in their residue level of $0.01-2.8{\mu}g/L$. Nine herbicides which include alachlor molinate, anilofos, butachlor, dimepiperate, metolachlor, oxadiazon, pretilachlor and thiobencarb were detected with frequencies of 0.8-22.9% and in their residue level of $0.01-9.07{\mu}g/L$. CONCLUSION: Detection frequencies and residue levels of insecticides and herbicides were the highest in waters sampled in May and June. Almost pesticides detected were for the paddy rice and their residue levels were very low to compare with standard values.

• Food Science and Preservation
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• v.14 no.2
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• pp.124-130
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• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.77-83
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• 2013

This study was performed to investigate pre-harvest residue limit (PHRL) in amaranth, to estimate biological half-life of emamectin benzoate and identify the characteristics of the residue. Pesticides of standard and double appplication rate, were sprayed once on amaranth at 0, 1, 2, 3, 5, 7, 10, 14 days before harvest. Amaranth sample was extracted with acetonitrile and partitioned with dichloromethane, and pesticide residues were determined with LC/MS/MS. The limit of detection of emamectin benzoate was 0.01 mg/kg. Recoveries of emamectin benzoate ($B_{1a}$, $B_{1b}$) at two fortification levels of 0.1 and 0.5 mg/kg, $B_{1a}$ were $93.3{\pm}0.7%$ and $93.2{\pm}7.7%$, $B_{1b}$ were $106.6{\pm}1.9%$ and $80.5{\pm}6.6%$, respectively. The biological half-lives of emamectin benzoate were about 2.0 days at standard application rate and 1.7 days at double application rate, respectively. The PHRL of emamectin benzoate were recommended as 0.84 mg/kg for 10 days before harvest.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.366-373
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• 2011

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.