• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.201-206
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• 2013

The second-order rate constants have been measured spectrophotometrically for the reactions of paraoxon 1 and parathion 2 with a series of alicyclic secondary amines, $OH^-$ and $HOO^-$ ions in $H_2O$ at $25.0{\pm}0.1^{\circ}C$. A linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.40 was obtained for the reactions of 1 with amines and $OH^-$. The reaction has been concluded to proceed through a concerted mechanism. $HOO^-$ deviates positively from the linear Br${\o}$nsted-type plot, implying that the ${\alpha}$-effect is operative. The magnitude of the ${\alpha}$-effect ($k_{HOO^-}/k_{OH^-}$) was found to be ca. 55 for the reaction of 1 and 290 for that of parathion 2, indicating that $HOO^-$ is highly effective in decomposition of the toxic phosphorus compounds although it is over 4 $pK_a$ units less basic than $OH^-$. Among the theories suggested as origins of the ${\alpha}$-effect (e.g., TS stabilization through an intramolecular Hbonding interaction, solvent effect, and polarizability effect), polarizability effect appears to be the most important factor for the ${\alpha}$-effect in this study, since the polarizable $HOO^-$ exhibits a larger ${\alpha}$-effect for the reaction of the more polarizable substrate 2.

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.61-66
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• 1987

1. In the vegetable crops, only MEP and Malathion showed a litte higher positive rate than other pesticides in general. On the other hand, parathion and captan were not detectable at all. 2. In the fruits, pesticides, MEP, PAP and Parathion had a little high positive rate, and Diazinon, and captan were not detectable at all. 3. However, the detected values of the pesticides in the vegetables and fruits were far below from korean tolerances and internationally recommended limits and tolerances, showing only $\frac{1}{3}{\sim}\frac{1}{66}$ and $\frac{1}{8}{\sim}\frac{1}{500}$ of Korean tolerance in vegetables and fruits, respectively.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.12a
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• pp.114-115
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• 2004

• Journal of Environmental Science International
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• v.15 no.3
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• pp.229-236
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• 2006

Organophosphorus pesticides (OPPs) contents in the sewage sludge derived from the residential and industrial areas were determined in order to characterize contemporary organic contamination levels as a part of the ongoing development of the environmentally sound sewage sludge management strategy in Korea. OPPs were extracted from freeze-dried sludges in a ultrasonic extractor. The extracts were cleaned-up by florisil column and subsequently fed into gas chromatograph/nitrogen phosphorus detector (GC/NPD) for determining OPP contents. Diazinon, dimethoate, disulfoton, EPN, malathion, methyl parathion, parathion, phorate and sulfotep were present in the appreciable amount in the domestic sewage sludges. The sum of the 9 OPPs in the sewage sludge varied from 534.8 to 15552.1 ${\mu}g/kg$, dry wt..

• Journal of Food Hygiene and Safety
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• v.9 no.4
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• pp.185-189
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• 1994

This study was to investigate time-dependent degradation process under various pH condition for organophosphorus(org-p) insecticides, namely Demeton-s-methyl, diazinon, Parathion, Phenthoate, and EPN in several waters. They were analysed by GC-FTD according to standard methods for the examination of water and wastewater. In pH=4, diazinon showed disappearance after 14 days in chromatogram. In pH=11, org-p insecticides were almost degradable after 7 days. In this condition, effect of pH on degradation process was greater than of light. In pH=7, org-p insecticides persisted residues after 112 days except Demeton-s-methyl. In BOD5 120, 250 ppm and domestic water, org-p insecticides showed also rapid degradation process.

• Journal of environmental and Sanitary engineering
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• v.9 no.2
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• pp.101-109
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• 1994

Acute toxicity of heavy metals( mercury, cadmium lead, chromium and copper ), organophosphours insecticides( EPN, 2, 4- D, and parathion ), and other chemicals( arsenic, cyanide, and phenol ) to Daphnia magna was analyzed. Acute toxicity of heavy metals, organophosphours insecticides and other chemicals on Daphnia magna, LC$_{50}$ was showed 0.07-0.73mg/1, 0.22-1.94mg/t and 1.73-39.92mg/1 respectively. Daphnia magna to most of toxic chemicals was sensitive and then it seems to be useful except phenol in toxic test of water. Toxic chemicals were classified as Group 1 which had a high LC$_{50}$ value and the low increase rate of toxicity according to the increase of concentration, Group 2 which had a high LC$_{50}$ value and the high increase rate of toxicity, Group 3 which had a low LC$_{50}$ value and the low increase rate of toxicity. To Daphnia magna, lead, chromium, EPN, and parathion were included in Group 1; Mercury and copper in Group 2; Arsenic and cadmium in Group 3; Cyanide 2,4- D, and phenol in Group 4.

• Archives of Pharmacal Research
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• v.23 no.3
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• pp.222-225
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• 2000

A series of conformationally controlled 2-PAM derivatives were prepared from 2-acetylpyridine and 2,3-pyrido[b]cycloalkenones in two steps and their reactivities towards parathion poisoned AChE were evaluated. The most planar 2,3-pyrido[b]cyclohexanone oxime methiodide showed an activity comparable to 2-PAM Implying E-syn is that the most active comformation of 2-PAM in the biological system.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.182.1-182.1
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• 2003

• Journal of Food Hygiene and Safety
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• v.3 no.3
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• pp.131-137
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• 1988

A pesticide monitoring survey was undertaken for the both 30 samples of pears and sweet persimmons from chief producing districts in1985 to evaluate pesticide residues in these agrcultural products and also to give basic informations in establishing maximum residue limits. Pesticide residues in pears were detected with fairly low in 7-60% of total samples. Even the maximum residue levels were only in the amount of 1/53-2/3 compared with maximum residue limits established in fruits in Environment Administration, Korea. Most of the residues (71-82%) was remained in peels of pears. Incase of sweet persimmons, captan, captafol, EPN, parathion, and phenthoate residues were also detected with fairly low in 3-20% of total samples. Presently, it is considered that pesticide residues in pears and sweet persimmons may be no harmful levels for food commodities.

• Journal of environmental and Sanitary engineering
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• v.10 no.2
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• pp.46-58
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• 1995

Acute toxicity of heavy metals( Mercury, Cadmium, Lead, Chromium and Copper ), Organophosphorus insecticides( EPN, 2, 4- D, and Parathion ), and other chemicals( Arsenic, Cyanide, and Phenol) to Daphnia magna, and Vibrio fischeri was analysed. Daphnia magna to most toxic chemicals was most sensitive among test organisms alld then Daphnia magna seems to be more useful in toxic test of water. Daphnia magna was more sensitive to heavy metals than insecticides and other chemicals. The sensitivity of Visrio JircAeri to heavy metals was not so different from that to insecticides and the sensitivity to other chemicals was low. Visrio JircAeri appears to be more sensitive to toxic chemicals than Photobacterium phosphoreum, which was compared as recorded values of P.phosphoreum. Toxic chemicals were classified as Group 1 which had a high $EC_{50}$ or $LC_{50}$ value and the low increase rate of toxicity according to the increase of concentration, Group 2 which had a high $EC_{50}$ or $LC_{50}$ value and the high increase rate of toxicity, Group 3 which had a low $EC_{50}$ or $LC_{50}$ value and the high increase rate of toxicity, and Group 4 which had a low $EC_{50}$ or $LC_{50}$ value and the low increase rate of toxicity. To Daphnia magna, Lead, Chromium EPN, and Parathion were included in Group 1 : Mercury and Copper in Group 2 : Arsonic and Cadmium in Group 3 : Cyanide, 2, 4-B, and Phenol in Group 4. To Visrio JircAeri, Lead, Chromiurl 2, 4- D, and Parathion were included in Group 1 : Merecury, Cadmium and Arsenic in Group 2 : Cyanide in Group 3 : EPN, Copper, and Phenol in Group 4.