• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.225-232
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• 2015

A liquid chromatography-electrospray ionization-tandem mass spectrometry method (LC-ESI-MS/MS) was used for determining seven pesticides (2,4-dichlorophenoxyacetic acid, methomyl, aldicarb, 2-methyl- 4-chlorophenoxy- acetic acid, molinate, carbaryl and carbofuran) and two synthetic materials (quinoline and bisphenol-A) in surface water. The analytes were extracted using solid-phase extraction (SPE). The eluate was concentrated by nitrogen gas. 100 microliters of 30% (v/v) methanol aqueous solution were used to dissolve the residue and an aliquot of the reconstituted solution was directly injected into LC-ESI-MS/MS after the filtration using 0.2 μm polytetrafluoroethylene (PTFE) syringe filter. Under the established condition, the calibration curves of the analytes were linear with correlation coefficients of above 0.997. The quantification limit was 0.002~0.011 μg/L and the relative standard deviations were less than 16.4%. In addition, accuracy was in the range of 84~107% and the recoveries were values between 56.2 and 98.6%. In this study, the developed method was applied to the analysis of real surface water samples.

• Membrane Journal
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• v.17 no.2
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• pp.99-111
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• 2007

It is impossible to remove toxic organic substances that are recognized as a cancer caused suspicious element in drinking water using the conventional water purification method. This study introduces groundwater into a reaction chamber as an effective amount of water to process this water using a mixed method of AOP oxidation and M/F membrane and purifies it as a desirable level by artificially mixing such toxic substances in order to effectively process the water. Based on this fact, this study configures an optimal operation condition. The VOCs existed in toxic substances was investigated as a term of phenol and toluene, and agricultural chemicals were also investigated as a term of parathion, diazinon and carbaryl. The experiment applied in this study was performed using a single and composite soolution. In the operation condition applied to fully dissolve and remove such substances, the amount of $H_2O_2$ injected in the process was 150 mL of a fixed quantity, the value of pH was configured as $5.5{\sim}6.0$, the temperature was controlled as a range of $12{\sim}16^{\circ}C$, the dissolved amount of ozone was applied more than 5.0 mg/L, the reaction time was determined as an optimal condition, such as $30{\sim}40$ minutes, and the segregation membrane in the same reactor was determined for acquire water drinking of large quantity using a pore size of $0.45{\mu}m$ M/F membrane.

• Journal of Food Hygiene and Safety
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• v.2 no.3
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• pp.121-136
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• 1987

As a part of continuing monitoring program since 1983, a study on pesticide residues on Korean agricultural products has been conducted to offer the tolerance of pesticide residues suiting Korean reality. The samples used in this experiment were collected from four areas in five provinces of Korea. The residue, levels of organochlorine pesticide (two kinds), organophosphoric pesticide (eight kinds) and carbamate pesticide (three kinds) on lettuce, garland chrysanthemum, radish Korean, potato, egg plant, green onion, persimmon and sweet potato, and the residue levels of captan and captafol on tomato, green pepper fresh, apple, peach, soybean, cucumber and cabbage Korean were determined by GC-NPD and ECD.

• Herbal Formula Science
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• v.24 no.2
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• pp.80-99
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• 2016

Objectives : Instrumental chemical analysis was utilized to investigate the effect of Add-Omit-Saenghyeoryunbu-eum(AO-SHU) on diabetic treatment. One of the most exciting, yet also controversial, arguments is the safety and biological mechanisms of the natural medicine on human body. Therefore, the aim of this study is to provide a better understanding on bioactive chemical components, hazards of heavy metal contamination and biological mechanism of the diabetic medicine composed of 12 different natural herbs. Methods : To study bioactive compound and metallic component in the diabetic medicine in detail, LC-MS/MS (Liquid Chromatography-Mass/Mass), GC (Gas Chromatography) and ICP (Inductively Coupled Plasma) were utilized to characterize the extract of the diabetic medicine and the result was compared with 18 marker substances selected from literature survey. In addition, in vitro assay experiments including GPR 119 activity and human DGAT-1 inhibition, and OGTT (Oral Glucose Tolerance Test) were performed to verify the effectiveness of this medicine on diabetic treatment. Results : Out of 18 marker substances, 9 bioactive compounds were identified from LC-MS/MS analysis which include Citruline, Catalpol, Berberine, Ginsenoside Rb1, Ginsenoside Rg1, Oleanolic acid, β-Sitosterol, Mangiferin, and Schizandrin. ICP study on 245 residual pesticides revealed that 239 species were not detected but 6 species, Dimethomorph, Trifloxystrobin, Pyraclostrobin, Isoprocarb, Carbaryl and Flubendiamide, while the amounts are trace levels, below permitted concentrations. The biological activity was observed in vitro assay and Oral Glucose Tolerance Test(OGTT), which are consistent with a preliminary clinical test result, a drop in blood sugar level after taking this herbal medicine. Conclusions : Instrumental chemical analysis using LC-MS/MS, GC, and ICP was conducted successfully to identify bioactive compounds in AO-SHU for the treatment of diabetes, finding 9 bioactive compounds. Furthermore, in vitro assay experiments and OGTT show that AO-SHU has its biological activities, which imply that it can be a candidate for the future diabetes remedy.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.85-97
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• 2012

The monitoring of pesticide residues was performed on 33 fruit commodities collected in Gyeonggi-do, Korea from 2006 to 2010. Pesticide residues were detected in 431 samples (16.8%) of total 2,558 samples and violated in 12 samples (0.5%). Annual detection rate showed 6.9%~19.4% with the rate of violation of 0.3%~0.9%. Twenty three samples (69.7%) of 33 commodities were detected and 4 samples (12.1%) were violated. Eight pesticides (EPN, dicofol, carbaryl, procymidone, methidathion, prothiofos, fenitrothion and phenthoate) were violated and 62 pesticides were detected. Chloropyrifos was detected most frequently. The rate of detection and violation of citrus fruits in fruits showed the highest level. Organophosphorus pesticides (35%) and insecticide (57%) were detected most frequently. The hazard index (%ADI) of chronic dietary risk assessment by deterministic approach showed that the lower limit value and upper limit value for the whole population were 0.0000~0.7526 and 0.0000~1.3237 respectively. For the only consumer group, the lower limit value and upper limit value were 0.0006~9.7801 and 0.0058~15.9258 respectively. Therefore the hazard index for the whole population and the only consumer group were evaluated as a safe level.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.441-452
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• 2011

This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.141-147
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• 2008

Globally Harmonized System (GHS) for classification and labelling will provide an internationally agreed hazard classification system of chemical products and for communication of those hazards. This study aimed for establishment of the oral acute toxic class (ATC) method and application of GHS on pesticides. The ATC method was developed for determining $LD_{50}$ estimates of chemical substances with significantly fewer animals than needed when applying conventional $LD_{50}$ tests. We carried out $LD_{50}$ test and ATC test on 13 pesticides, Although methidathion EC and parathion-ethyl EC showed significantly different in $LD_{50}$ values between $LD_{50}$ test and ATC method, there are no difference in toxicity class by GHS. Both tests on the other pesticides showed almost equal results and toxicity class by GHS. Therefore, this study indicated high possibility of application of ATC method and GHS on pesticides.