• 월간산업보건
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• no.9 s.245
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• pp.16-19
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• 2008

• The Korean Journal of Pesticide Science
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• v.9 no.3
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• pp.214-220
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• 2005

Initial Risk assessments using physicochemical properties and acute toxicity are conducted to provide information for managers to decide the potential adverse effects and played as a tool for decision-making in development of new substances. In this study, we built initial risk assessment framework and carried out human and ecology initial risk assessment for three different pesticides of captan, glyphosate, and paraquat dichloride to confirm our framework. Two water estimation models of GENEEC (GENeric Estimated Environmental Concentration) and FOCUS (FOrum for the Co-ordination of pesticide models and their USe) were employed for pesticides exposure assessment. Application for paraquat dichloride and glyphosate uses shows very low human and ecology risk. On the other hand, high acute ecological risk was observed from the application for captan. These results showed good agreements with the U.S. EPA RED (Reregistration Eligibility Decision) reports verifying the framework of this study.

• The Korean Journal of Pesticide Science
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• v.17 no.1
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• pp.20-26
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• 2013

This study was carried out of investigate the effect of weed control methods on the growth of 'campbell early' grape at the vineyards which was divided into the 18 zone ($3.5m{\times}5.5m/zone$) in the grape research institute. It's investigated control effects, growth and quantity of grape and dominant weed of July~August by sprayed glufosinate ammonium and paraquat dichloride each 3 times, fabric covering, grass planting (Festuca myuros), mechanical weeding (3 times). The weed showed total of 16 species at the vineyards. Late-May to early growth stage of grape was dominated Chenopodium album and Trifolium repens, but to late growth stage of grape from mid-July was dominated Erigeron canadensis, Echinochloa crus-galli and Chenopodium album. Weed control effect of 10 day after treatment showed fabric covering 100%, grass planting (Festuca myuros L.) 95.3%, mechanical weeding 81.9%, glufosinate ammonium (3 times) 98.1% and paraquat dichloride (3 times) 90.4%, respectively. Growth of grape was higher herbicides treatment and mechanical weeding than others. Yield tended to be higher glufosinate ammonium (3 times) and paraquat dichloride (3 times) each 12.6 kg/tree, 12.3 kg/tree than others.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.283-288
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• 1995

This study was carried out to investigate the toxic action of herbicide, paraquat(1,1'-dimethyl-4,4'-bipyridylium-dichloride), against microorganisms. The toxic effect of paraquat was observed mainly using Escherichia coli(KCTC 1039), as follows; Growth of aerobic microorganisms which comprise 4 strains of bacteria and 2 strains of yeast and 4 strains of mold was inhibited drastically in the presence of 1.0mM paraquat But the growth of anaerobic bacteria was not affected by the chemical. When actively growing cells of E. coli were exposed to the paraquat at the concentration higher than 1.0 mM, they rapidly lost their ability to form colony and clearly formed inhibitory zone by well test More than 50% of the cells were killed by 1.0 mM paraquat treatment, even at immediate addition of paraquat to the medium.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.1-7
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• 2000

The bacterial strain JW-2 which conferred resistance against paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride) was isolated from soil. The strain was identified as an Ochrobactrum anthropi based on its morphological, physiological, biological and fatty acid composition, and was designated as Ochrobactrum anthropi JW-2. We compard paraquat resistance of O. anthropi JW-2 with Escherichia coli J105. In the presence of 100mM paraquat, E. coli JM105 was not grown whereas the growth rate of O. anthropi was about 70% of control. We compared the sensitivity of O. anthropi JW-2 and E. coli J105 to redox-cycling compounds such as paraquat, plumbagin or menadione, which are known to exacebate wuperoxide generation. O. anthropi JW-2 did not show cross-resistance to plumbagin or menadione. superoxide dismutase activity was increased in paraqunt-treated E. coli JM105 while it was not increased in O.anthropi JW-2. These results suggest that the mechanism of paraquat resistance in O.anthropi JW-2 is probably due to selectively decreased permeability toward paraquat by membrane protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.849-855
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• 1994

Actively growin Excherichia coli(KCTC 1039) cells were treated with paraquat (1, 1'-dimethyl-4, 4'-bipyridili-um dichloride) by cultivating them in the presence of 1.0mM paraquat. The treatment was carried out with or without shaking to understand the effect of oxygen on paraquat action to thebacterial superoxide dismutase (SOd). By the treatment with vigorous shaking , population growth of the organism almostly stopped and specific activities of SOD of the cells drastically decreased. On contrast ot it, the herbicide showed only l limited inhibitory action on bacterial growth and SOD activity by stationary treatment. Proteins prepared from parquat-treated cells divided into two peaks by Sephacryl column chormatogrpahy, while proteins from the intact cells formed a single peak. Cytoplasmic proteins and plasma membrane proteins of intact cells formed separated three peaks by Sephadex G-75 column chormatography. respectively. Among them the second peak disappeared by paraquat treatment , while the third peak became more apparent. Fractions from the first and the third peak showed SOD activity. Paraquat was detected from the same fractions.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.1
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• pp.29-38
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• 1999

Three kinds of soil surface applied herbicides and three kinds of foliage applied herbicides were used to study weed control effect, appropriate concentration, phyto-toxicity against trees and economical efficiency of weed control on trees, Pinus thunbergii, Picea abies, Chamaecyparis obtusa, Quercus accutissima, and Fraxinus rhynchopylla in a nursery. The results were obtained as follows; 1.The control effect of the soil surface applied herbicides showed that the three herbicides; Alachlor, Pendimenthalin and Simazine were alike in their holding effect of weed development, and the sensibility of weed spp. on the herbicides was different. The mean control effect was 58~89%. 2. The weed control effect of the foliage applied herbicides demonstrated that Paraquat dichloride was the best of 84~95% and followed by Glufosnate ammonium and Glyphosate. Especially when the half of its standard amount was treated, the effect of Paraquat dichloride was higher than the other herbicides. 3. Generally, the weed control effect became better as the concentration of the herbcide getting higher. As the concentration of the herbicide got higher, the restraining effect of weed development was continued for a long time in the soil surface applied herbicides, while the weed control effect appeared earlier in the foliage applied herbicides. 4. As the result of the soil surface treatments, 20% of short seedings of Fraxinus rhychopylla treated with twice amount of standard Alachlor died and the rest seeding showed low growth. In the other treatments, there was neither harmful effect of herbicides on the seedings nor growth decrease of them compared to those weeded by men. 5. When treated with foliage applied herbcides, leaves were partially of and discolorated in most treatments. About 0.4~6.2% of Fraxinus thynchopylla, which had short seedings died, and there was no difference in growth with the other treatments. 6. The herbicides showed better economical efficiency over 68% than weed control by men. Especially, Alachlaor of the soil surface applied herbicides showed the highest efficiency(77.6%), while Paraquat dichloride of the foliage applied herbicides was the best(70.3%)..

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.339-347
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• 1994

This study was carried out to investigate the pathological changes with paraquat(1.1'-dimethyl-4.4'-dipyrildiylium dichloride) administered by intraperitoneally, orally, skin applied in mice, rats and rabbits. Results were obtained as follows; In 2 days after paraquat administration clinical signs anorexia, depression, tachypnea, and tachycardia, respiratory failure, coma and death were observed in mice, rats and rabbits. Compared toxicity of paraquat with mouse were observed toward to paraquat that resistance was strong than rats and rabbits. Also, mortality of skin application were found the low than intraperitoneal and high than oral administration. In the case of gross observation were appear lips moisture in orally administered rats and rabbits by skin application. Lung of all laboratory animals were observed congestion and haemorrhage, swelling or atrophy. In the case of microscopic findings were severe congestion and haemorrhage, interstitial pneumonia of lung. Congestion and haemorrhage of liver, congestion and haemorrhage, renal tubule epithelium necrosis of kidney were observed in mice, rats and rabbits. Skin application group of mice, rats and rabbits showed infiltration of inflammatory cells and folliculitis of epidermis and dermis. Also, in oral administration group showed congestion and haemorrhage, tachment, necrosis of alimentary tract mucosa.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.304-310
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• 2005

This study was carried out to investigate the effect of herbicide paraquat (1,1-dimethyl-4,4-bipyridilium dichloride) on the electron transport system of the cell. When actively growing cells of bacteria were exposed to the 1.0 mM paraquat, more than $50\%$ of the cells were killed at 0 hour. But specific activities of superoxide dismutase (SOD) were not changed at 0 hour of paraquat treatment. Oxido-reductions of NAD (H) by the suspension of bacterial membtane, rat mithochondria and NAD-dependent dehydrogenase were accelerated by paraquat treatment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.59-66
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• 1997

This experiment was conducted at the forage experimental field, College of Agriculture and Life Sciences, Seoul National University, Suweon in 1992 and 1993 to investigate the effects of tillage method-conventional and rotary-till, rye (Secde cereale L.) harvest date-early (April 14) and late (April 26), and rye residue treatmentno paraquat(1, 1-dinethyl-4,4'-bipyridinium dichloride) and paraquat in minimizing the adverse effects of the rye residue on growth and yield of succeeding corn(Zea mays L.). Corn plant height during the growing season was slighly taller with conventional tillage relative to rotary-till when rye was harvested in early and treated by paraquat. Corn LA1 during the growing season was slighly increased when rye was harvested in early and where conventional tillage was used with paraquat treatment. There were no differences in the leaf number and silking dates of corn among the tillage methods, harvest dates of rye and paraquat treatments. The dry matter yield of corn was significantly increased by paraquat treatment when rye was harvest in early, but no differences were found in the dry matter percentage, ear percent to total dry matter, and stover, ear and estimated TDN yields of corn among the treatments.