• Korean journal of applied entomology
• /
• v.35 no.1
• /
• pp.74-79
• /
• 1996

General esterases were analysed quantitatively and qualitatively to see their role in deltamethrin resistance mechanisms of the diamondback moth, Plutella xylostella L. Selection with 0.1 g of deltamethrin in each generation induced the moth to decrease susceptibility to the insecticide and to increase esterase activities of the fourth instar larvae. Both characters were highly correlated so that the correlation coefficient (r) between LDSo @g) of deltamethrin and esterase activities (~M/min/pg) was 0.9918 (P=0.0082). Nondenaturing PAGE (6%) separated 17 esterase bands from the whole body extracts of the fourth instar larvae. Deltamethrin-selected populations had fewer esterase bands than had the unselected. Four esterase bands (E3, E4, Ell, and E13) were, however, specific to deltamethrin-selected populations.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.1
• /
• pp.55-64
• /
• 2022

BACKGROUND: This study was conducted to evaluate the residual characteristics and safety assessment of αcypermethrin and deltamethrin in minor crops, chives and spring onion cultivated in greenhouse. METHODS AND RESULTS: The insecticides α-cypermethrin 2% EC and deltamethrin 1% EC used in the experiment were diluted 1,000 times and then sprayed on chives and spring onion twice with 1-week intervals at 0, 7, 14, and 21 days before harvest. The residual insecticides were extracted from the minor crops using QuEchERS method and analyzed by GC-MS/MS. The average initial residues of α-cypermethrin and deltamethrin in chives after 21 days decreased from 2.74 to 0.82 mg/kg and 1.12 to 0.16 mg/kg, respectively. Similarly, in spring onion the residues after the same periods decreased from 0.26 to <0.01 mg/kg for α-cypermethrin and from 0.07 to <0.01 mg/kg for deltamethrin. CONCLUSION(S): The PHIs (pre-harvest intervals) for α-cypermethrin and deltamethrin in chives are recommended as 14 days before harvest with twice applications of the pesticides, whereas for α-cypermethrin in spring onion PHI of 7 days before harvest is recommended with 3 times of applications and PHI of 21 days for deltamethrin. The theoretical maximum daily intakes of cypermethrin and deltamethrin were 68.8% and 64.2%, respectively, indicating that residues of both compounds did not pose considerable health risks to consumers.

• Korean Journal of Environmental Agriculture
• /
• v.36 no.4
• /
• pp.293-298
• /
• 2017

BACKGROUND: Pyrethroids (PYRs) are a widely used insecticide in agriculture and household area. In mammals, PYRs such as deltamethrin is metabolized to 3-phenoxybenzoic acid (3-PBA) in liver that is mainly excreted in urine. This study is designed to single exposure of deltamethrin to rats in a dose-dependent manner and identify the correlation between deltamethrin exposure and its metabolite (3-PBA) in urine. METHODS AND RESULTS: Exposure levels of deltamethrin were control (0 mg/kg bw), low (0.0705 mg/kg bw), medium (0.705 mg/kg bw) and high (7.05 mg/kg bw) dose. Low concentration was derived by ussing Korea predictive operator exposure model (KoPOEM). Dermal exposure persisted for 6 h, and urine specimens were collected for 24 h. The urine matrix was removed after a series of procedures and 3-PBA was analyzed by gas chromatography/mass spectrometry. CONCLUSION: There was a strong correlation ($R^2=0.83$) between the amount of oral exposure to delta me thrin and urinary levelof3-PBAexcreted. In dermal exposure groups of deltamethrin except high-dose, also there was a good correlation between urinary 3-PBA and deltamethrin exposure, but not stronger than in oral deltamethrin exposure groups. Based on these results, therefore, the amount of 3-PBA in urine can be used as a good monitoring indicator that reflexing the exposure level of deltamethrin to human body.

• Korean Journal of Environmental Agriculture
• /
• v.32 no.1
• /
• pp.78-83
• /
• 2013

BACKGROUND: This study was performed to investigate the change of deltamethrin residue after spraying for control of hygienic insects in bush of levee at Bansuk-dong stream (A) and Juk-dong ditch (B) in Yuseong, Daejeon. The drop concentrations and disappearance of deltamethrin residue in stream water were determined to evaluate the toxic effects of stream ecosystem. METHODS AND RESULTS: Water samples were collected at 7 points including 0, 5, 10, 20, 40, 70 and 100 m downstream from the deltamethrin spraying point. Water sample was partitioned into dichloromethane, and was determined with GC/${\mu}$-ECD. Limit of Quantitation of deltamethrin was 0.04 ${\mu}g/L$. Recoveries of deltamethrin at two fortification levels of 0.4 and 2.0 ${\mu}g/L$ were $91.57{\pm}3.13%$(n=3) and $94.40{\pm}4.59%$(n=3) in A stream, and $88.24{\pm}3.33%$(n=3) and $85.20{\pm}3.73%$(n=3) in B stream, respectively. Residue of A stream were from <0.04 ${\mu}g/L$ to 0.48 ${\mu}g/L$ and B stream were from 0.08 ${\mu}g/L$ to 14.95 ${\mu}g/L$ under practice application condition. And residues were from <0.04 ${\mu}g/L$ to 0.2 ${\mu}g/L$ in A stream treated deltamethrin with 1.0 mg level at the upper region. CONCLUSION(S): Practice application of deltamethrin for the pest control of waterside was not much shown toxic effect to ecosystem of stream.

• Korean journal of applied entomology
• /
• v.35 no.3
• /
• pp.249-253
• /
• 1996

In the laboratory study, the toxicities of chlorpyrifos-methyl, chlorpyrifos, etofenprox, etofenprox+PAF' and deltamethrin for different larval instars of S. litura decreased significantly as larvae aged. LCso values for chlorpyrifos- methyl and chlorpyrifos increased significantly from 3rd instar larvae, while those for etofenprox+PAP and deltamethrin-increased from 2nd instar larvae. In pot study, no significant differences in control efficacy were observed among each treated plots and over 90% control efficacy at 5 d after treatment was obtained in all of the treated plots, except treatment with deltamethrin. Therefore four insecticides excluding deltamethrin will be effective for controlling S. litura. However, it will be probably important to select appropriate insecticides and decide a proper time of treatment because the developmental stage is a significant factor in deciding insecticide efficacy because various developmental stages of the tobacco cutworm inhibit in fields.

• The Korean Journal of Pesticide Science
• /
• v.5 no.2
• /
• pp.62-66
• /
• 2001

The thirteen commercial insecticides to Lycoriella mali were investigated on their insecticidal activities and mycelial growth of two Letinula edodes strains. For the adults, insecticides showing over 95% insecticidal activity were chlorpyrifos-methyl, fenthion, fenitrothion, benfuracarb, furathiocarb and deltamethrin. For tile larvae, diflubenzuron and cyromazine showed over 90% insecticidal activity. Fenthion, benfuracarb, furathiocarb, deltamethrin, diflubenzuron and cyromazine did not affect the mycelial growth of L. edodes strain, in Imhyup 1 variety. And deltamethrin, diflubenzuron and cyromazine did not affect that in Sanlim-5. Insecticides showing over 80% residual effect for 14 days were benfuracarb to the adults and diflubenzuron and cyromazine to the larvae. Control effect of furathiocarb, fenthion, benfuracarb, deltamethrin, diflubenzuron and cyromazine against larvae of Lycoriella mali showed 90% ten days after application under sawdust cultivation. Among them, benfuracarb, fenthion and furathiocarb revealed excellent control effect against adults. These results indicate that benfuracarb, fenthion, and furathiocarb can be used for the control of Lycoriella mali in the field. However, further studies are needed on the effect of insecticides treatment oil fruit-body yield and chemical residue in the mushroom tissues.

• The Korean Journal of Pesticide Science
• /
• v.17 no.2
• /
• pp.126-132
• /
• 2013

The objectives of this study were to provide the basic data of the residue of deltamethrin in the stream water. Deltamethrin was treated on side of Ban-Suk stream and Juk-Dong ditch for hygienic purpose by air spray. The drift concentration of deltamethrin was investigated with different wind speed condition on Ban-Suk stream (A), and the change of residue with time course on Juck-dong ford (B). Also we found the residual change of deltamethrin until 48 hour in Yu-Seong stream confluence (C) where two streams join. Maximum residues of A were $0.17{\mu}g/L$ (5 min, 200 m) at strong wind speed and $4.42{\mu}g/L$ (0 min, 25 m) at moderate wind speed according to different wind velocity. Residues of B were $0.15{\sim}0.26{\mu}g/L$ (0~480 min) after spraying, and decreased to a non-detected level after 720 min. Residues of C were $0.15{\mu}g/L$ (0 min), $0.11{\mu}g/L$ (1 min) and $0.10{\mu}g/L$ (12 hr) after spraying, and no residues were detected in any other samples. From these results, it is concluded that deltamethrin residues in water should be rapidly diluted into stream water and affected negligible toxic effect to stream ecosystem.

• Journal of Korean Society of Forest Science
• /
• v.87 no.4
• /
• pp.571-576
• /
• 1998

Experiments were conducted to evaluate the efficacy of the application of low concentration insecticides by sprinkler system for control of the pine needle gall midge, Thecodiplasis japonensis, by killing the adults emerging and copulating near the ground. For ground spray, 2 insecticides of fenitrothion and deltamethrin, dilutions of $2,000{\times}$ and $3,000{\times}$ deltamethrin, and 3 spray intervals of 1-3 day were tested at the peak time of adult emergence during the day time. The results are as follows ; 1. Ground spray of fenitrothion 50% EC and deltamethrin 1% EC were found to be highly effective for control of the pine needle gall midge. Average gall formation by fenitrothion, deltamethrin and untreated ones were 3.40%, 5.23% and 45.69%, respectively ; control value of both insecticides exceeded 88%. 2. As a ground spray of deltamethrin 1% EC, dilution $2,000{\times}$ was significantly different from $3,000{\times}$ in gall formation rates. Average gall formation of $2,000{\times}$ plots and $3,000{\times}$ treated ones were 5.23% and 18.00% ; control values were 89.44% and 63.66%, respectively. 3. Diurnal treatment of ground spray was found to be highly effective for control of pine needle gall midge. 4. In particular, control by ground application of dilutions $2,000{\times}$ and $3,000{\times}$ of deltamethrin is suggested because it does not have an adverse effect on arthropods of the ground surface such as ants and spiders.

• The Korean Journal of Pesticide Science
• /
• v.12 no.2
• /
• pp.148-154
• /
• 2008

This study was carried out to investigate the residue patterns of two insecticides, lambda-cyhalothrin and deltamethrin, commonly used for lettuce, under greenhouse conditions. The pesticides were sprayed with dilution of recommended and doubled doses onto lettuce. Their detection limits were $0.001\;mg{\cdot}kg^{-1}$ and mean recoveries at the fortification levels of 0.2 and $1.0\;mg{\cdot}kg^{-1}$ were from 101.17 to 104.25 and from 99.70 to 103.77%, respectively. The pesticides were gradually decreased in lettuce with time. Biological half-lives of lambda-cyhalothrin and deltamethrin were 1.7 and 1.4 days at the recommended dose and 1.8 and 1.4 days at the doubled dose, respectively. Initial residue amounts of lambda-cyhalothrin and deltamethrin at the recommended and doubled doses exceeded their MRLs. However, the residue levels of the pesticides in the crop sampled at harvest were less than their MRLs. The ratios of the estimated daily intake (EDI) to acceptable daily intake (ADI) by intake the crop harvested 10 days after spraying were less than 1% of their ADIs.

• Asian Journal of Turfgrass Science
• /
• v.15 no.3
• /
• pp.119-126
• /
• 2001

The susceptibility of Ectinohoplia rufipes, insect pest of landscaping trees in golf courses to registered insecticides in golf courses was investigated. In addition, effect of host plants, Ainus firma, Prunus serrulata var. spontanae, and Osmantus asiaticus on susceptibility of E. rufipes were tested in laboratory with efficacy of some insecticides in laboratory and fields. The insecticides used in experiments were cabaryl 40%+phosalone 20% WP, chlorpyrifos-methyl 25% EC, chlorpyrifos 20% + diflubenzuron 7% n, deltamethrin 1% EC, ethopenprox 8% +diazinon 25% WP, and fenitrothion 50% EC. Mortalities of E.rufipes were 100% except chlorpyrifos-methyl. when A. firma leaves dipped in recommended concentration of given insecticides were supplied as food to adult of E. rufipes. LC$_{50}$s of insecticides were different depending on host plants, that is, those of deltamethrin were 0.21 ppm in Ο. asiaticus, 0.45 ppm in P. serrulata var. spontanae, and 0.77 ppm in A. firma. LC$_{50}$s of fenitrothion were 24.1 ppm, 64.0 ppm, and 11.0 ppm and those of chlorpyrifos-methyl were 97.2 ppm, 40.6 ppm, and 29.6 ppm, respectively. LC$_{50}$ was the lowest in Ο. asiaticus and that of chlorpyrifos-methyl and fenitrothion was the lowest in A. firma. Deltamethrin was the most effective against adult of E. rufipes in field like in laboratory and persisted in two weeks.weeks.