• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.04a
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• pp.342-347
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• 1999

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.139-142
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• 1998

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.04a
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• pp.358-360
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• 1999

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2001.06a
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• pp.104-104
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• 2001

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.163-167
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• 2002

$TiO_2$ 고정화 지지체를 이용한 유기인계농약의 광분해에 대한 연구 결과 다음과 같은 결론을 얻을 수 있었다. Chlorpyrifos의 광분해 제거효율을 초기 pH 9에서는 반응시간 200분만에 완전 분해되었으며, 초기 pH 7, 5에서는 각각 반응시간 240분, 260분만에 완전히 분해되었다. 또한 Diazinon인 경우 초기 pH 9에서는 반응시간 200분만에 완전 분해되었으며, 초기 pH 7, 5에서는 각각 반응시간 220분, 240분만에 완전히 분해되었다. Chlorphyrifos와 Diazinon은 pH가 증가할수록 즉 산성에서 염기성쪽로 갈수록 반응속도가 증가하는 것을 볼 수 있었다.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.21-26
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• 2001

Risk assessment traditionally are conducted on individual chemicals; however, humans are exposed to multiple chemicals in daily life. The organophosphorus (OP) pesticides are considered in a single risk assessment because they act by a common mechanism of toxicity, and there is likely to be expose to multiple OP pesticides simultaneously or sequentially. The OP pesticides act by inhibiting the enzyme acetylcholinesterasc (AChE) and have available extensive database. AChE is widely distributed throughout the body, most importantly in the nervous system. Inhibition of AChE results in accumulation of acetylcholine in the nervous system that results in clinical signs of cholinergic toxicity, including increased salivation and lacrimation, nausea and vomiting, muscle fasciculation, lethargy and fatigue, among others. To conduct an exposure assessment for pesticides in the diet, we need to know the food consumption patterns of the populations, and the pesticide residue levels in the foods that are consumed. This study was conducted to identify cumulative dietary risk due to multiple OP pesticides that can be exposed through various foods. Total 22 food samples including cereals, vegetables and fruits were collected randomly two times from food markets in several sites (4 cities). The subjected foods were selected by regarding of highly consumed foods to general Korean people. The 12 OP pesticides including Acephate, Azinphos-methyl, Chlorpyrifos, and Diazinon were monitored. For the exposure assessment, general adult group of 60 kg body weight was regarded as target population and food consumption data suggested by Lee et al. (2000) were used as consumed value of individual food. Analyses of samples for OP pesticides have been carried out according to the multiclass multiresidue analysis method and acephate and methamidophos analysis method of Korea Food Code. In general the levels of OP pesticides found in the food samples were very low or not detected.

• Journal of the Korean Chemical Society
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• v.43 no.6
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• pp.663-669
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• 1999

For determination of separated pesticides by using GC and HPLC, liquid-liquid extraction(LLE) and solid phase extraction(SPE) have been carried out to separate and concentrate the organophophorous pesticides such as Diazinon, Fenitrothion, Phosmet, Phosalon and EPN in environmental water samples. ln determination of pesticides by HPLC/UV, SPE has resulted in higher recovery and more precision than LLE, while in determination of pesticides by GC/FPD, vice versa. HPLC/UV after the pretreatment process of sample by solid phase extraction (SPE-HPLC/UV) has suggested the possibility of determination of pesticides ppb level. ln comparison of detection limit, both SPE-HPLC/UV and LLE-GC/FPD are reasonably suitable for analysis of residue pesticides. ln the respect of the rapidity and the solvent required, SPE-HPLC/UV method has proven to be superior to LLE-GC/FPD.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.265-272
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• 2002

This study was carried out with the detection for multiresidue of the organophosphorus pesticides such as malathion, parathion. diazinon, and carbamate pesticide such as carbaryl, by enzyme-inhibition method. The acetylcholinesterase (AChE) and cholinesterase (ChE) activities in chicken brain determined by the Ellman's method were 166.6 and 5.8 $\mu$mol/min/g protein, and in chicken plasma were 23.1 and 8.3 $\mu$mol/min/g protein, respectively. The optimum pH of AChE and ChE was 8.2 and 7.8, respectively. The Km of AChE and ChE was 0.034 and 0.045 mM, respectively. I$\_$50/ for AChE and ChE by some organophosphorus was 55.82 and 99.42 mg/L of malathion, 31.16 and 29.13 mg/L of parathion, and 17.89 and 19.62 mg/L of diazinon, respectively. I$\_$50/ for AChE and ChE by carbaryl of carbamate was 0.10 and 0.05 mg/L, respectively. The 0.07 mg/L of drinking water advisory level for carbaryl could be detected with I$\_$50/ of AChE and ChE. Enzyme-Inhibition (EI) method with AChE and ChE was used the multiresidue method to detect the 1 mg/L of the carbamate pesticides.

• The Korean Journal of Pesticide Science
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• v.18 no.1
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• pp.41-47
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• 2014

This study was performed to evaluate the exposure level of organophosphorus and pyrethroid pesticide to floriculture workers and florists. The urinary dialkylphosphates, metabolites of organophosphorus insecticides, including dimethylphosphate (DMP), diethylphosphate (DEP), dimethylthiophosphate (DMTP), diethylthiophosphate(DETP) and pyrethroids of metabolites, cis/trans DCCA, DBCA, and 3-PBA were analysed to evaluate the exposure of organophosphorus and pyrethroid pesticide to floriculture workers and florists. The concentration of DMP is highest in floriculture workers. but the concentration of DETP is highest in retail florist. The concentration of 3-PBA is highest in floriculture workers. The amount of organophosphorus and pyrethroid pesticide expusure is highest in flower workers, wholesale florist and retail florists are followed. The management for reducing pesticide exposure to floriculture workers and wholesale florist is required.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.269-276
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• 2019

A colorimetric rapid detection method based on acetylcholinesterase (AChE) was developed for the analysis of organophosphorus (OP) and carbamate (CB) pesticides. The AChE catalyzes acetylthiocholine into thiocholine having (-) and (+) charges, and the (+) charge results in gold nanoparticle (GNP) aggregation. The in-activation of AChE by OP and CB has been well known. In order to optimize the colorimetric method, optimal dilution times of commercial serum containing AChE, diameter of GNP, and concentration of acetylthiocholine were tested as a key parameter. The colorimetric detection limits of the method were 7.5 ng/mL for both dimethyl amine and carbofuran pesticides in 60% ethanol. No cross-reaction to other chemicals, such as aflatoxin B1 and ochratoxin A, which can be contaminated with pesticides in agricultural products, was observed. Recoveries from lettuce, sesame leaf, and cabbage lettuce spiked with known concentrations of dimethyl amine and carbofuran were found to be ranged from 83.85 to 133.16%. These results indicated that the colorimetric rapid method based on AChE can be a useful tool for the sensitive, specific, rapid, and accurate detection of OP and CB pesticides in fresh vegetables.