• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.289-294
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• 2005

The toxic effects of 12 commercially available insecticides on the earthworm, Eisenia fetida (Savigny), were evaluated using artificial soil, surface sprayed soil, immersion, and contact filter tests. The risk to earthworm was assessed by the TER (toxic exposure ratio) value, which was calculated by the formula, TER=NOEC/PEC (predicted environmental concentration). TER was 3 for methomyl SL, 20 for carbaryl WP, 20 for phosphamidon SL, 30 for imidacloprid WP, and 60 for dichlorvos EC the in artificial soil test. At recommended, the earthworm mortality to methomyl SL reached 50% in the surface sprayed soil test, 72% in the immersion test, 30% in the contact filter paper test, whereas that to imidacloprid WP reached 56, 32, and 100 respectively. As a result of the four methods, methomyl SL and imidacloprid WP would be toxic insecticides to earthworm.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.296-300
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• 2004

The rejection properties of 6 aromatic pesticides were evaluated by a continuous flow system equipped with a hollow fiber NF membrane. Different from the separation experiment of batch cell, the rejection and the removal could be calculated exactly because the concentration of feed, permeate and retentate was separately obtained. The lowest and the highest rejection were found in carbaryl(54.8%) and methoxychlor(99.2%), respectively, and the removals were always shown higher than rejections. This may be caused by some reasons such as the solute adsorption on the membrane, the variation of feed concentration. Although molecular weight, molecular width regarded as solute characteristics and log P(n-octanol/water partition coefficient) as hydrophobicity could be applied to explain the rejection property, these factors should be considered together for better analysis. According to the higher relationship between log B(solute permeability) and molecular weight, it was revealed that the solute separation with this membrane was influenced more by molecular weight.

• Korean Journal of Medicinal Crop Science
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• v.8 no.1
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• pp.74-78
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• 2000

This study was carried out to select the effective insecticides for control of Ostrinia furnacalis(Guenee) in Yonchon, northern part of Kyunggi province, where is main producing region of adlay in Korea. The Asian corn borer in adlay field had three generations a year. The first stage of adult activity was higher from late May to middle June, the second from late July to early August and the third late September. Based on difference in control value, the relative ranks of some insecticides were lambda cyhalothrin EC > cartap hydrochloride GR > carbaryl EC. In control value by different application timing of Lambda cyhalothrin EC, yields were significantly different, that is, twice applications on second generation showed the control value of $90.6%{\sim}93.5%$. Unhulled grain yield on Lambda cyhalothrin EC treated plot on second generation was higher than that in untreatred plot by 82%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.405-410
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• 2000

This experiment was conducted to investigate to the degree of damage by stink bugs at the soybean fields of Kyong-buk Agricultural Research and Extension Services from 1997 to 1998. Thirty different soybean varieties including Hwangkeumkong were used. Stink bugs collected in the soybean fields were Riptortus clavatus, Nazara antennata, Piezodorus hybneri, Dolycoris baccarum, and Halyomorpha halys, etc. The damage rates by stink bug were 5.0-12.5% in determinate types and 36.1-50.0% in indeterminate ones, which indicated that stink bugs preferred indeterminate types to determinate ones. The control values to sting bugs by fenitrothion, triaazophos, and carbaryl, were 83.4%, 69.5%, and 87.0%, respectively.

• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.448-456
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• 2012

Thirty-seven carbofuran-degrading bacteria were isolated from agricultural soils, and their genetic and phenotypic characteristics were investigated. The isolates were able to utilize carbofuran as a sole source of carbon and energy. Analysis of the 16S rRNA gene sequence indicated that the isolates were related to members of the genera Rhodococcus, Sphingomonas, and Sphingobium, including new types of carbofuran-degrading bacteria, Bosea and Microbacterium. Among the 37 isolates, 15 different chromosomal DNA patterns were obtained by polymerase chain reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences. Five of the 15 representative isolates were able to degrade carbofuran phenol, fenoxycarb, and carbaryl, in addition to carbofuran. Ten of the 15 representative isolates had 1 to 8 plasmids. Among the 10 plasmid-containing isolates, plasmid-cured strains were obtained from 5 strains. The cured strains could not degrade carbofuran and other pesticides anymore, suggesting that the carbofuran degradative genes were on the plasmid DNAs in these strains. When analyzed with PCR amplification and dot-blot hybridization using the primers targeting for the previously reported carbofuran hydrolase gene (mcd), all of the isolates did not show any positive signals, suggesting that their carbofuran hydrolase genes had no significant sequence homology with the mcd gene.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.108-113
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• 1998

Egasyn is accessory protein of ${\beta}$-glucuronidase(${\beta}$-G) in the liver microsomes. Liver microsomal ${\beta}$-G is stabilized within the luminal site of the microsomal vesicles by complexation with egasyn which is one of carboxylesterase isozymes. We investigated the effects of organophosphorus compounds(OPs) such as insecticides on the dissociation of egasyn-${\beta}$-glucuronidase(EG) complex. The EG complex was easily dissociated by administration of OPs, i.e., Fenitrothion, EPN, Phenthionate, and bis-p-nitrophenyl phosphate(BNPP), and resulting ${\beta}$-G dissociated was released into blood, leading to the rapid and transient increase of plasma ${\beta}$-G level with a concomitant decrease of liver microsomal ${\beta}$-G level. In a case of phenthionate treatment, less increase in plasma ${\beta}$-G level was observed, as compared with those of other OPs. This may be explained by a fact that phenthionate was easily hydrolyzed by carboxylesterase. Similarly, carbamate insecticides such as Carbaryl caused rapid increase of plasma ${\beta}$-G level. In contrast, no significant increase of plasma ${\beta}$-G level was observed when pyrethroid insecticides were administered to rats. This is due to a fact that pyrethroids such as Phenthrin and Allethrin were easily hydrolyzed by A-esterase as well as carboxylesterase. On the other hand, addition of OPs to the incubation mixture containing liver microsomes caused the release of ${\beta}$-G from microsomes to the medium. From these in vivo and in vitro data, it is concluded that increase of the plasma ${\beta}$-G level after OPs administration is much more sensitive biomarker than cholinesterase inhibition to acute intoxication of OPs and carbamates.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.166-171
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• 1984

The present studies were conducted to investigate the relative toxicity of several insecticides to the rice insect pests and the predatious spider, Pirate subpiraticus. In laboratory test by topical application, BPMC and MIPC for the plant and leafhoppers were toxic to Nilaparvata lugens, but less toxic to Pirata subpiraticus. Other carbamate insecticides such as carbaryl, carbofuran, and MTMC showed highly toxic effect on P. subpiraticus as well as N. lugens. No organophosphates showed selective toxicity to P. subpiraticus. Thiocyclam, effective to Chilo suppressalis and Sesamia inferens, had highly good selective toxicity to P. subpiraticus. In case of insecticides for Nephotettix cincticeps, BPMC only had a little selective toxicity between N. cincticeps and P. subpiraticus. Organophosphate insecticides which had been reported to induce chemical resistance to N. cincticeps showed high $LD_{50}$ value to N. cincticeps. In pot trials, dust formulation was more toxic to P. subpiraticus than emulsifiable concentrate. It was more toxic to P. subpiraticus to increase number. of insecticide application.

• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.25-32
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• 1996

The Bioconcentration factor(BCF) is used as an important criterion in the risk assessment of environmental contaminants. Also it can be used as indicator of biomagnification of environmentally hazardous chemicals through food-chain as well as a tool for ranking the bioconcentration potential of the chemicals in the environment. This paper reports the measured BCF value on carbofuran in Carassius auratus(goldfish), under steady state, and examined corelation between the BCF value and the depuration rate constant. Carassius auratus(goldfish) was chosen as test organism and test periods were 1-day, 3-day and 5-day. Experimental concentrations were 0.05, 0.10 and 0.50 ppm. Carbofuran in fish tissue and in test water was extracted with n-hexane and acetonitril. GC-ECD was used to detect and quantitate carbofuran. The depuration rate of carbofuran from the whole body of goldfish is determined over the 24-h period after treatment. The obtained results were as follows: 1. It was possible to determine short term BCFs of carbofuran through relatively simple procedure in environmental concentrations. 2. $BCF_1$ of carbofuran in concentration of 0.05, 0.10 and 0.50 ppm were 1.66, 1.64 0.61, $BCF_3$ were 2.08, 2.14, 0.66 and $BCF_5$ were 2.21, 2.57, 0.86, respectively. 3. Carbofuran concentration in fish extract was increased as increasing test concentration and prolonging test period, but $BCF_s$ in concentration of 0.50 ppm was greately decreased. 4. Determined deputation rate constants of carbofuran in concentration of 0.05, 0.10, 0.50 ppm were 0.076, 0.082 and 0.089, respectively. 5. It is considered that great decrease of $BCF_s$ in concentration of 0.50 ppm is due to high water solubility and stability of carbofuran in testwater. 6. It is suggested that low BCF of carbofuran is due to its relatively high water solubility and depuration rate, compared to BPMC, carbaryl and chlorothalonil.

• Journal of Korean Society on Water Environment
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• v.23 no.2
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• pp.193-200
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• 2007

The AOPs research defined by creating a sufficient amount of OH radicals from the dissolution of organic materials through photoxidation and research for a complete elimination of residual organic materials by membrane are actively ongoing. This research focuses on the hybrid processing of AOPs and M/F membrane to dissolve and eliminate organic chemicals in drinking water which are suspected of carcinogens. For this purpose, underground water was used as a source of drinking water for the hybrid processing of AOPs oxidation and M/F membrane, and a pilot plant test device was installed indoor. Carcinogenic chemicals of VOCs and pesticide were artificially mixed with the drinking water, which was then diluted close to natural water in order to examine treatment efficiency and draw optimal operation conditions. The samples used for this experiment include four chemicals phenol, chloroform, in VOCs and parathion, carbaryl in pesticide. As a result of the experiments conducted with simple, and compound solutions, the conditions to sufficiently dissolve and eliminate carcinogenic chemicals from the hybrid processing of where carcinogens were artificially added are : (hydrogen peroxide) prescribed solution 100 mg/L under pH 5.5~6.0, and the temperature $12{\sim}16^{\circ}C$, at the normal temperature and pressure. $d-O_3$ volume of 5.0 ppm and above and 30-40 minutes of reaction time are most appropriate and using MF/UF for membrane was ideal.

• Korean Journal of Environmental Agriculture
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• v.34 no.4
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• pp.274-281
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• 2015

BACKGROUND: A lasting release of low levels of persistence chemicals including pesticides and pharmaceuticals into river has a bad influence on aquatic ecosystems and humans. The present study monitored pesticide residues in the Yeongsan and Seomjin river basins and their tributaries as a fundamental study for water quality standard of pesticides.METHODS AND RESULTS: Nine pesticides(aldicarb, carbaryl, carbofuran, chlorpyrifos, 2,4-D, MCPA, methomyl, metolachlor, and molinate) were determined from water samples using SPE-Oasis HLB(pH 2) and LC/MS/MS. Validation of the method was conducted through matrix-matched internal calibration curve, method detection limit(MDL), limit of quantification(LOQ), accuracy, precision, and recovery. MDLs of all pesticides satisfied the GV/10 values. Linearity(r²) was 0.9965- 0.9999, and a percentage of accuracy, precision, and recovery was 89.4-113.6%, 3.1-14.0%, and 90.8-106.2%, respectively. All pesticides exclusive of aldicarb were determined in the river samples, and there was a connection between the positive monitoring results and agricultural use of the pesticides.CONCLUSION: Monitoring outcomes of the present study implied that pesticides were a possible non-point pollutant source in the Yeongsan and Seomjin river basins and tributaries. Therefore, it is required to produce and accumulate more monitoring results on pesticides in river waters to set water quality standards, finally to preserve aquatic ecosystems.