• Proceedings of the PSK Conference
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• 2002.04a
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• pp.134.1-134.1
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• 2002

• Environmental Analysis Health and Toxicology
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• v.17 no.4
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• pp.325-332
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• 2002

A helper T(Th)1-mediated response is known to enhance cell -mediated immunity, while a Th2-mediated response is associated with the humoral immunity that if elevated IgE levels and eosinophilia. Prostaglandin (PG)E$_2$results in the decreased capability of Iymphocytes to produce Thl cytokines, with a shift toward a Th2 cytokine response. Chlorpyrifos (CPF) has been reported to impair the blastogenesis and response of T Iymphocytes. CPF also induces delayed febrile effects, which results from the activation of COX -PGE$_2$pathway. The purpose of this study is to determine the effort of CPF on the in vitro production of Th cytokines and the role of PGE$_2$on the CPF-induced production of Th cytokines. Splenocytes obtained from male BALB/c mice were pretreated with CPF(0.1, 1, 10 and 100$\mu$M) in the presence of absence of indomethacin or PGE$_2$for 12 h and then were incubated with concanavalin (Con) A for 48 h. These results showed that CPF remarkedly reduced the production of splenic interleukin (IL)-2 and interferon (IFN)-γ in a dose-dependent manner. CPF significantly increased the splenic IL-4 production at low doses (0.1 and 1$\mu$M) but did not affect at high doses (10 and 100 $\mu$M). Indomethacin reduced the CPF-decreased production of IL-2 and IFN-γ in a dose -dependent manner and significantly attenuated the production of IL-4 increased by CPF 0.1 $\mu$M. High dose of CPF significantly reduced the PGE$_2$-decreased production of IL-2 and IFN-γ, while the PGE$_2$- induced production of IL-4 was significantly enhanced by CPF 1 $\mu$M. These findings suggest that CPF nay down-regulate the immune response of Th 1 type by the suppressed production of IL-2 and IFN-γ, with a shift toward a Th2 cytokine response. The CPF-decreased production of Thl cytokines may not be mediated by endogenous PGE$_2$. Also, CPF may attenuate the exogenous PGE$_2$-decreased Th 1 immune response in a dose--dependent manner but may affect dose-independently the PGE$_2$-induced Th2 immune response.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.537-544
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• 2007

This study was carried out to investigate adsorption characteristics of residual pesticides on an adsorbent. $Bauxsol^{TM}$ and mackban-stone as adsorbent were used. Analytical method for residual pesticides was established by GC/NPD and $GC/{\mu}ECD$. Pesticides used in this study were ${\alpha}$-endosulfan, ${\beta}$-endosulfan, pendimethalin and chlorpyrifos-methyl, fenitrothion, and recovery rates were more than 97%. Adsorption rate on an adsorbent was decreased in order of endosulfan, chlorpyrifos-methyl, pendimethalin, fenitrothion. Organochlorine pesticides showed higher removal rate than the other pesticides. $Bauxsol^{TM}$ gave both chemical decomposition and physical adsorption. Mackban-stone gave only physical adsorption on the other hand. The high pH and chloric ions structure of eluted solution have greatly affected at chemical resolution. The removal rate of pesticides was increased due to the physical property of adsorbent, i.e. high porosity. The above adsorbent is to be a candidate to remove residual pesticides in water and pond of links.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.221-231
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• 2018

The susceptibility of the western flower thrips, Frankliniella occidentalis and garden thrips, Frankliniella intonsa was evaluated using 51 commercial insecticides. 15 kinds of insecticides which showed more than 90% mortality against both thrips, F. occidentalis and F. intonsa was selected. Many active ingredients were misused and abused in commercial mixture formulation insecticides. Since the F. intonsa was more susceptible than F. occidentalis, it was considered that both thrips can be controlled by insecticides that showed insecticidal activity on the F. occidentalis. Lethal time ($LT_{50}$ and $LT_{95}$), systemic toxicity and residual toxicity of selected insecticides were compared. Both chlorpyrifos WP and chlorpyrifos + diflubenzuron WP revealed the fastest toxicity within 2 h ($LT_{95}$), while spinetoram WG revealed the slowest toxicity as 62.3 h ($LT_{95}$). Chlorfenapyr SC showed toxicity at foliar and drenching application while spinetoram WG was toxic only in foliar application. Chlorfenapyr SC showed residual effect at 3, 5, 7, 10, 15 days after treatment and both benfuracarb WG and chlorpyrifos WP showed residual effect at 3 days after treatment. As a result of treatment of selected insecticides for field population of F. occidentalis, the population collected from horticultural crops showed lower susceptibility than the population collected from vegetable crops.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.440-445
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• 2010

This study was carried out to investigate the toxicities of five registered insecticides to the Lycorma delicatula nymphs and adults. Insecticidal activities were evaluated by testing systemic and residual effects in the laboratory, and control efficacy in the vineyard. For the 3rd nymphal instars and adults, etofenprox+diazinon, chlorpyrifos, etofenprox, dinotefuran and imidacloprid showed perfect insecticidal activity. The systemic effects of dinotefuran and etofenprox+diazinon on grape roots at half concentration were showed the adult mortality of 82.2% and 84.4%, respectively. Chlorpyrifos at recommended concentration was showed mortality of 86.0%. The leaf systemic effects at recommended and half concentrations of all insecticides except dinotefuran were lower than 65% but the mortality at double concentration of chlorpyrifos, dinotefuran, etofenprox were more than 82%. The residual effect between etofenprox+diazinon and dinotefuran at recommended and double concentrations were 100% at 14 days after treatment, the other insecticides have low efficacy. All the four insecticides showed 87% control value on nymphs in the field test and adults appeared more than 96% control value st and adinotefuran, etofenprox+diazinon, however, the other insecticides decreased to 59.1 % and 61.2%. Therefore, dinotefuran and etofenprox+diazinon showing high systemic effects to roots and long residual effects to leafs have high control efficacies.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.382-390
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• 2008

This study was performed to evaluate the acute toxicity and residual toxicity of the 69 kinds of agrochemicals (41 insecticides, 18 fungicides, and 10 acaricides) against honeybee, Apis mellifera and bumblebee, Bombus terrestris. According to the IOBC standard, the toxicity showed below 30% was classified as non-toxic. Among 41 insecticides, five insecticides (acetamiprid, chlorfenapyr, thiacloprid, milbemectin, and buprofezin+amitraz) against the honeybee; eight insecticides (methomyl, thiodicarb, acetamiprid, chlorfenapyr, thiacloprid, abamectin, spino sad, buprofezin+amitraz) against the bumblebee did not show any toxic effect. Therefore, it thought to being safe. Other 18 fungicides and 10 acaricides were safe against the honeybee and bumblebee. In residual toxicity against the honeybee, eight insecticides (dichlorvos, methomyl, imidachlorprid, emamectin benzoate, spinosad, cartap hydrochloride, chlorfenapyr, and endosulfan) among 41 insecticides tested were safe at three days after treatment; however, sixteen insecticides (dimethoate, fenitrothion, fenthion, methidathion, phenthoate, pyraclofos, fenpropathrin, clothianidin, dinotefuran, thiamethoxam, abamectin, acetamiprid+ethofenprox, acetamiprid+indoxacarb, bifenthrin+imidacloprid, ethofenprox+phenthoate, imidacloprid+methiocarb) still remain high toxicity at eleven days after treatment. Against the bumblebee, residual toxicity showed as safe in seven insecticides (dimethoate, methidation, a-cypermethion, ethofenprox, indoxcarb, chlorpyrifos+a-cypennethrin, esfenvalerate+fenitrochion) at three days after treatment; however, eight insecticides (fenitrothion, pyraclofos, clothianidin, fipronil, acetamiprid+ethofenprox, chlorpyrifos+bifenthrin, ethofenprox+phenthoate, imidacloprid+methiocarb) still showed high toxicity at seven days after treatment. From above results, it will be useful information to select insecticides being safe and effective against the honeybee and bumblebee.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.79-83
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• 1980

The toxicities of some soil insecticides were evaluated in terms of the tolerance to various larval-ins tars of the common cutworm (Agrotis fucosa Butler) using topical application method in the laboratory. $LD_{50}$ values(ug/larva) were determined by the probit analysis and the tolerance-values were obtained with '$LD_{50}$ values for from 2nd-to 6th-instars/$LD_{50}$ values for first-instars.' The relative toxicities of the insecticides were 31so compared with the $LD_{50}$ values for the instars. The degree of tolerance was greatly increased as the larval instar advanced; the ranges of tolerance between the first-and 6th-instar larvae to the insecticides phoxim (Volaton), diazinon, chlorpyrifos (Dursban), carbofuran (Curaterr) and Mocap were 251.6, 126.6, 97.5, 44.3, and 18.7 times, respectively. The average relative toxicities of the insecticides for the instars indicated that the toxicity of phoxim was the greatest and following carbofuran, chlorpyrifos, Mocap and diazinon.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.9-22
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• 2020

This study was designed to use the safety management data for residual pesticides in imported banana based on the investigation of pesticide residue detection of agricultural products with different origins in the Republic of Korea. From the USA, EU, UK, Japan and Korea from 2007 to 2018, the results of banana residue pesticides were summarized into detected pesticides, number of inspections, number of pesticide detection cases, and the amount of detected pesticide residue. A total of 109 pesticides were detected for the pesticide residue and pesticide detection rate was 4.58% in 206,894 cases. The detection rate was ranged within 10.62-24.62% for chlorpyrifos, imazalil, methyl-bromide, azoxystrobin, carbendazim, pretilachlor and thiabendazole. Among them, chlorpyrifos was detected most often followed by imazalil, azoxystrobin, thiabendazole, bifenthrin and carbendazim. According to the results of monitoring data for bananas in EU, Japan, USA, UK and Korea, the kinds of detected pesticides were 85, 57, 23, 18 and 8, respectively. Azoxystrobin, bifenthrin and chloropyrifos were found in monitoring data of all countries. Fourteen and twelve pesticides were detected in bananas from Costa Rica and Ecuador, respectively. Imazalil and thiabendazole were detected in 16 and 11 origins, respectively. Myclobutanil and iprodione were detected in four and two countries, respectively. In bananas from Costa Rica, azoxystrobin and bifenthrin were detected 11.8 and 9.8%, respectively, and the detection rate of azoxystrobin was 19% in bananas from Colombia. Chlorpyrifos was detected 22.7, 13.3 and 10.8% in bananas from Belize, Colombia and Costa Rica respectively. Myclobutanil was detected in bananas from Colombia and Costa Rica with the rate of 17.9 and 10.4%, respectively.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.239-246
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• 1993

In order to clarify the possible contamination of rice straw used as a crude feed for livestock, Korean native cattle and cow, by pesticides, the samples collected from 21 sites in Korea were analyzed by a multiresidue method for 10 pesticides with GLC to obtain the following results. 1. Detection limits were 0.001ppm in butachlor, 0.002ppm in chlorpyrifos, 0.003ppm in BPMC, pirimiphos-methyl and diazinon, 0.004ppm in fenitrothion, 0.005ppm in phenthoate, 0.009ppm in IBP, 0.015ppm in carbofuran, and 0.03ppm in carbaryl. 2. In recovery tests, 73-101% of the pesticides applied were recovered, the recovery being low in carbofuran and chlorpyrifos. 3. Butachlor, 2-chloroacetanilide herbicide, and BPMC, carbaryl, and carbofuran, carbamate insecticides, were not detected in any sample. 4. In organophosphorus insecticides, the amounts of fenitrothion in sample No. 1, 2, 4, 5, 7, 12, 20 and 21 were in the range of 0.01-0.05ppm, those of phenthoate detected in sample No. 10 and 12 were 0.4 and 0.17ppm, respectively, and those of IBP in all samples, with the exception of sample No. 7, 12, 16, 17, 20, and 21, were in the range of 0.01-0.20ppm. The residues of chlorpyrifos, diazinon, and pirimiphos-methyl were not detected.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.91-99
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• 2010

Two pesticides commonly used in spinach were subjected to a field residue trial to ensure safety of terminal residues in the harvest. The residual patterns of two pesticides, which were Azoxystrobin and chlorpyrifos were examined after applying with the recommended dose and their $DT_{50}$ were calculated. Also degradation patterns of pesticides at storage $4^{\circ}C$ were compared to those at $20^{\circ}C$, and removal rates of pesticides by washing spinach with water were measured. Biological half-lives of azoxystrobin and chlorpyrifos were 3.2~3.8 and 3.8~4.7 days, respectively. During the storage period, the degradation patterns were appeared more obviously at $20^{\circ}C$ than $4^{\circ}C$. Removal rates of azoxystrobin and chlorpyrifos were 9.6~90.0% and 17.7~85.8% by various washing methods.