• Journal of environmental and Sanitary engineering
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• v.10 no.2
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• pp.59-66
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• 1995

According to the population increase and industrialization, the drinking water source, Han River and other sources, are contaminated by industrial wastewater, domestic sewage, and agricultural discharges. Among the contaminants, and toxic substances, pesticides is most interesting items (or human health Our drinking water has some problems of THMs, Fe, odor, etc., $o many people use groundwater or bottled water. But sometimes there are many reports about groundwater contamination owing to the agricultural chemicals, waste disposal, industrial wastewater. In America, there are about 45,000 groundwave supply company and in korea about 20% of total population are using groundwave as drinking water source. In America, studies about SEE is increasing Instead of liquid- liquid extraction method, because of many advantages of SEE methods. Author tried to investigate SPE methods in the spiked water samples to compare with liquid- liquid extraction method and got the following results. The amount of organic solvents which are used In SPE method is less than 1/10 compared with liquid- liquid method, the analytical duration time is shortened, and the ethyl acetate was good fluent among several organic solvents.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.643-648
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• 2005

The objective of this paper is to analyze the environmental effects by the fertilizer change with wastewater reuse for agriculture. For this research, Lysimeter tests are being implemented to cultivate rice with different levels of fertilizer applications with wastewater irrigation., and to analyze the nutrient loading by wastwater reuse in paddy fields was examined the CREAMS-PADDY model. CREAMS-PADDY model is modified from CREAMS model for considering the hydrologic cycles in paddy field. As a result, in the lysimeter treated by irrigation with wastewater and chemical fertilizer with half of the conventional amount showed generally similar tendency to the control plot. This may require the modifications of standard cultural practices for rice in terms of fertilizer and pesticide applications. However, high concentration of sodium in wastewater might cause damage to physico-chemical properties of paddy soil. And the wastewater reuse effects on nutrient loads were quantitatively analyzed and this results provide the reasonable management for agricultural reuse.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3341-3347
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• 2010

A series of oxazolidinone-based strobilurin analogues were efficiently synthesized by the reaction of 3-(2-bromomethylphenyl) oxazolidin-2-one with 1-substituted phenyl-2H-pyrazolin-3-one. Their structures were confirmed and characterized by $^1H$-NMR, $^{13}C$-NMR, elemental analysis, and mass spectroscopy. In addition, the crystal structure of the target compound 3-(2-((1-phenyl-2H-pyrazol-3-yloxy)methyl)phenyl) oxazolidin-2-one was determined by single crystal X-ray diffraction. The bioassay results of these compounds indicated that some of the oxazolidin-2-one derivatives containing N-substituted phenyl 2H-pyrazol ring exhibited potential in vivo fungicidal activities against M. grisea at the dosage of $1\;g\;L^{-1}$.

• Environmental Analysis Health and Toxicology
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• v.13 no.3_4
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• pp.71-75
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• 1998

Carbendazim, which is widely used fungicide, was investigated for rat hepatocarcinogenesis using a medium-term carcinogenicity bioassay. All rats were initially given a single dose (200mg/kg) of diethylnitrosamine (DEN) i.p. and then, starting 2 weeks later, carbendazim treatment group and positive control group received carbendazim (7 mg/kg/ day) and 2-acetylaminofluorene (2-AAF, 1%), respectively, in the diet for 6 weeks. All rats were subjected to two-thirds partial hepatectomy (PH) at week 3 and sacrificed at week 8. Carcinogenic potential was scored by comparing the number and area per cm$^2$ of induced glutathione-S-transferase placental form (GST-P) positive foci in the liver. Carbendazim had no effect in the increase of body weight, hematological and biochemical values, and the number and area of GST-P positive loci. These results suggest that this bioassay using DEN-PH method can be useful for detection of hepatocarcinogenic potentials of pesticide.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.314-320
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• 2014

The uptake and transportation patterns of the residual boscalid and chlorfenapyr were investigated from the soils to Korean cabbages. The recovery rates of the pesticides spiked in the soils and Korean cabbages were 87.5 to 105.2%. Korean cabbages were cultivated in soils treated with two different concentrations of the pesticides as low (3.0 mg/kg) and high (6.0 mg/kg) concentrations in greenhouse for 28 days. The initial level of boscalid was determined as 2.77 and 5.66 mg/kg for the low and high concentration of boscalid-treated soils, respectively. After 28 days of treatment, the residual boscalid in soils decreased to 0.53 and 1.60 mg/kg for the low and high concentration of boscalid-treated soils, respectively, and thus it was reduced to 71.7 to 81.9%. The initial level of chlorfenapyr was determined as 2.38 and 6.43 mg/kg for the low and high concentration of chlorfenapyr-treated soils, respectively. After 28 days of treatment, the residual chlorfenapyr in soils decreased to 1.36 and 2.91 mg/kg for the low and high concentration-treated soils, respectively, and thus it was reduced to 42.9 to 54.8%. The residual pesticide analysis was done with 2 day intervals from 21 days-cultivated Korean cabbages after seeding. Uptake rates of boscalid from the soil to Korean cabbages were 2.4 and 2.2% for the low- and high-concentration of boscalid-treated soil, respectively. However, the uptake rate of chlorfenapyr by the cabbages was 1.5 and 1.3% for the low and high concentration-treated soil, respectively. The uptake rate of chlorfenapyr by the cabbages was lower than that of boscalid. These results showed that the residual pesticides in soil could be absorbed by Korean cabbages depending on their physicochemical properties.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.287-292
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• 2002

To establish effective and safe control method against Phytophthora root rot caused by Phytophthora capsici on tomato in hydroponic culture, three pesticides, oxadixyl copper hydroxide 8% WP, metalaxyl copper oxychloride 15% WP, and dimethomorph. dithianon 38% WP at 4 concentration levels were tested on potato dextrose agar medium inoculated with Phytophthora capsici. All pesticides inhibited mycelial growth, but two pesticides of them, metalaxyl copper oxychloride WP and dimethomorph. dithianon WP, were selected as effective pesticides for the efficacy test in a hydroponic culture. Forty days after transplanting of tomato seedlings, 4 ml of sporangia of P. capsici (about 25 sporangi/ml) per plot was inoculated around tomato plant root, and then 5 days after inoculation, the pesticides diluted at 5,000 times were drenched 1, 2 or 3 times per plot on the culture cube at 15 days interval. Fifteen days after drenching, tomato fruits and hydroponic culture solution were sampled for the analysis of pesticide residues. Dimethomorph was detected 0.001 and 0.003 mg/kg in tomato of the plots sprayed 2 and 3 times with dimethomorph dithianon WP of which detection levels were far below compared with 1.0 mg/kg of the Korean MRL of dimethomorph on tomato. Incidences of Phytophthora root rot were $30.5{\sim}50%$ in the plots drenched at 1 or 2 times with metalaxyl.copper oxychloride WP, and $16.7{\sim}25%$ in the plots treated with dimethomorph dithianon WP. However, there was no incidence of Phytophthora root rot in the plots treated at 3 times with both of pesticides, showing no phytotoxic effect. Based on the results, the drenching of these pesticides on the culture cube could be recommended as a very safe and effective control method for Phytophthora root rot in tomato.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.232-240
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• 2009

The aim of this study was to determine the processing and reduction factors for ginseng and its commodities during ginseng processing to obtain information of pesticide residue in ginseng. For this study, azoxystrobin was used in two field containing 6 years old ginseng plants. Ginsengs were harvested and processed to obtain different commodities (Dried ginseng, red ginseng and ginseng water and alcohol extracts, red ginseng water and alcohol extracts) for pesticide analysis. The amount of residue levels from wonju and icheon for fresh ginseng were 0.05, $0.03\;mg\;kg^{-1}$ dried ginseng were 0.12, $0.14\;mg\;kg^{-1}$, red ginseng were both $0.05\;mg\;kg^{-1}$, ginseng alcohol extract were 0.28, $0.33\;mg\;kg^{-1}$, ginseng water extract were 0.22, $0.16\;mg\;kg^{-1}$, red ginseng alcohol extract were 0.31, $0.20\;mg\;kg^{-1}$ and red ginseng water extract were 0.09, $0.11\;mg\;kg^{-1}$ respectively. These data were under MRLs notified by KFDA. The processing factors for ginseng products were 3.25, 1.34, 7.84, 4.63, 6.15 and 2.56 respectively. The reduction factors for ginseng products were 1.19, 0.51, 3.41, 1.91, 2.74 and 1.00 respectively. These data showed increment during processing which could be due to concentration but considering water contents, residue levels were similar or decreased than the initial residue level during processing.

• Food Science and Preservation
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• v.24 no.6
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• pp.802-812
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• 2017

This study was conducted to investigate the quality properties depending on the cultivation methods (general, organic, pesticide-free) of yuza and its various parts (peel, pulp, seed). The contents of hesperidin were the highest in yuza feel grown by pesticide-free method (13.23 mg/g). The contents of naringin presented a higher content in the peel, especially which of the general (4.62 mg/g) showed the highest value. Vitamin C analysis showed the highest content in the peel, significantly varied according to the cultivation method and various parts (p<0.05). Vitamin C value was significantly highest in organic peel, which was 770.02 mg/100 g, whereas among the peel, the pulp and the seed were it the lowest in the seed. The content of total polyphenols were the highest in general peel (0.85 mg/g). Flavonoid content of pesticide-free seed was significantly higher than those of the other yuja samples which was 0.89 mg/g (p<0.05). The DPPH radical scavenging activity was relatively more active in the peel among the above-mentioned three parts, especially the pesticide-free peel was most active, which was 73.94%. The ABTS radical scavenging activity of organic peel was significantly active among the samples, which was 84.47% (p<0.05). Based on these results, it can be said that yuja has variety of useful components in the pulp and the seed as well as the peel: and thus it's hight recommended to develop more varied yuja products.

• The Korean Journal of Pesticide Science
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• v.15 no.1
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• pp.36-47
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• 2011

This study was performed to investigate the contaminated status of endocrine disruptor-suspected pesticides in agricultural products distributed in northern Seoul in 20l0. We analyzed 33 kinds of pesticides by multiresidue analysis method in 3,081 samples. Twelve pesticidcs were detected 600 times and violated 22 times from the agricultural products. The highest frequency of detection was procymidone and that of violation was endosulfan. The highest rates of detection divided violation times as diazinon. In agricultural products, 466 samples had pesticide residues and 22 samples violated the maximum residue limits (MRLs). Agricultural products were also classified by type and red pepper powder belonged to the others was the highest detection rate at 70.7%, fruiting vegetables 35.3%, tea leaves 23.6%, stalk and stem vegetables 21.2%, fruits 14.6% and leafy vegetables 11.2%. The rates of violation sample were stalk and stem vegetables 1.1%, leafy vegetables 1.0% and roots and tubers 0.4%. Leek was to be managed primarily because it had the high detection and violation ratio and was detected together several pesticides.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.634-640
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• 2016

The objective of this study was to evaluate the effectiveness of using HR-GC/MS for the rapid screening of dieldrin residues in soils. Persistent organic pollutants (POPs) of organochlorine pesticides such as dieldrin, were analyzed in sedimentary rock and granite rock collected from greenhouses, Niigata, Japan. Dieldrin remains in Japanese farming soils, more than 40 years after their use as insecticides was prohibited. The averages in soil moisture ranged from 2.79% to 7.20% in soils derived from sedimentary rock and from 25.59% to 31.40% in soils derived from granite rock. Mean concentrations of dieldrin residues in sedimentary rock and granite rock were $39.7ng\;g^{-1}$ and $40.51ng\;g^{-1}$, respectively. Dieldrin residue was detected at a slightly higher concentration in granite rock than sedimentary rock samples. There was no consistency between the two soils or between surface and subsurface soils. The coefficients of variation of the two soils were 10.6% and 8.7%, respectively. These results suggest that our high-resolution mass spectrometry detector (HR-GC/MS) is effective at analyzing residual organochlorine pesticides in soil. In order to increase the precision and sensitivity for chemical analysis of POPs, high-resolution gas chromatography coupled with a HR-GC/MS is highly recommended.