• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.8-13
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• 1988

This experiment was conducted to evaluate the effect of polyethylene film(P.E.) mulching on degradation of the soil insecticides, endosulfan(6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), fonofos(O-ethyl S-phenyl ethylphosphonodithioate), and ethorprophos(O-ethyl S, S-dipropyl phosphorodithioate) in red pepper, peanut, and sesame fields. Degradation of endosulfan, fonofos and ethoprophos in the soils under P.E. mulching and non-mulching followed first-order kinetics. The half-lives of fonofos, ethoprophos, ${\alpha}-$ and ${\beta}-endosulfan$ were $19{\sim}21$, $25{\sim}37$, $33{\sim}39$ and $56{\sim}81$ days, respectively. There were few differences in the half-lives of fonofos in either mulching or non-mulching concitions. However, half-lives of α-endosulfan, ethoprophos, and ${\beta}-endosulfan$ were 6, 12 and 25 days longer under P.E. mulching than under non-mulching conditions, respectively. The effect of P.E. mulching on degradation was remarkable for the slower degrading insecticides. Residues of ethoprophos in the harvested sesame under P.E. mulching and non-mulching conditions were 0.024 and 0.074ppm, respectively. Residues of fonofos in the harvested peanuts under P.E. mulching and non-mulching conditions were 0.078 and 0.017ppm, respectively. However, no endosulfan was detected in the harvested red peppers under either condition.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.113-118
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• 1986

After selecting four places in the main shellfish habitat, 118 items of the sample were collected in the mud flat from August to October in 1983, in order to analyze organochlorine pesticide residues by a gas chromatograph equipped with an electron capture detector. The results obtained were summarized as follows; ${\alpha}-BHC,\;{\gamma}-BHC\;&\;PCNB,\;heptachlor,\;{\gamma}-endosulfan,\;{\beta}-endosulfan,$ p, p'-DDE, dieldrin, o, p'-DDT and p, p'-DDT were detected in the range from 2 to 98 percent and their levels of mean residues ranged from trace to 0.041ppm, in the order of ${\gamma}-BHC\;&\;PCNB,\;{\alpha}-BHC,\;heptachlor{\approx}{\alpha}-endosulfan{\approx}p, p`-DDE{\approx}dieldrin{\approx}{\beta}-endosulfan{\approx}$o, p'-DDT, and p, p'-DDT. The mean of total residues in regions was Kangjin(0.058ppm), Kwangyang(0.080ppm), Yoch'on (0.016ppm), and Yonggwang(0.75ppm). ${\gamma}-BHC\;&\;PCNB$ peak were separated by column packed with DC-200. PCNB was identified by making a PCA(pentachloroaniline), the reduced derivative of PCNB, and this confirmed that PCNB residues were detected in the soil sample.

• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.60-67
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• 2011

BACKGROUND: Because dried herbal medicines have many active ingredients, it is not easy to determine the residue amount after extraction, partition and clean up of pesticides from them. Especially, liquid-liquid partition method is consuming many times and solvents. Macroporous diatomaceous earth(MDE) column was used to replace the separatory funnel for liquid-liquid extraction with dichloromethane to analyze the endosulfan and its metabolite. METHODS AND RESULTS: The residue analysis method using MDE column instead of liquid-liquid partition for determining insecticide endosulfan and its metabolite in 4 dried herbal medicines was developed by GC/MS. As a result, the recovery rates of the pesticides in 4 herbal medicines were ranged from 80.3 to 93.5% for ${\alpha}$-endosulfan, from 81.0 to 100.3% for ${\beta}$-endosulfan and from 80.6 to 95.6% for endosulfan sulfate, respectively. The coefficients of variation for triplicate were ranged from 1.1 to 3.4%. CONCLUSION: The improved methods are more ecofriendly, safer, faster and less laborious than conventional method by KFDA.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.460-465
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• 2007

Endosulfan-${\alpha}$ endosulfan-${\beta}$ and endosulfan-sulfate, which are classified as pesticides, were degraded by use of UV energy and ultrasonic irradiation. The degradation residuals were analysed by gas chromatography with an electron capture detector and TOC (total oragnic carbon) analysis. The reactions were conducted in a quartz annular reactor equipped with a low pressure mercury multilamp (8Wx2) and a sonic generator. All the aqueous solutions were concentrated as 10 mg/L initially. Endosulfans were degraded each to result in 48.2% (${\alpha}$), 50.0% (${\beta}$) and 76.5% (sulfate) of removal efficiency by UV energy, and 66.9% (${\alpha}$), 55.8% (${\beta}$) and 72.7% (sulfate) by ultrasonic irradiation, respectively. In contrast to the results of the single-component solutions, degradation of the endosulfan-sulfate was greatly suppressed to result in the lowest degradation rate and removal efficiency in the three-component solutions. This finding suggests that there should be a reversible reaction with a substantially low equilibrium constant between endosulfan-${\alpha}$ or -${\beta}$ and -sulfate in the coexistence of the three endosulfans. TOC data showed the endosulfans were decomposed by 20%~40% toward complete mineralization, producing a quantity of intermediates induced by the radical reactions. We found that all the decay reactions considered in this study nicely fell into pseudo first-order rate.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.203-209
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• 1994

When $^{14}C-{\alpha}-endosulfan$ was incubated with carp liver, kidney and gut preparations, it was metabolized to water soluble and organosoluble metabolites. In an in vitro test, endosulfan was converted to endosulfan ${\alpha}-hydroxyether$ (EHE), endosulfan alcohol (EA) and endosulfan ether (EE). The addition of NADPH resulted in rapid conversion of endosulfan to the metabolites in 105,000 g soluble fraction and microsomes. However, the rate of metabolism of endosulfan in liver, kidney and gut supplemented with NADPH as a cofactor was higher in the 105,000 g soluble fraction than that in the microsomes of carp under incubation conditions. The enzymes probably involved in the metabolism of endosulfan include the glutathione S-transferase (GST) and the mixed function oxidases (MFO), based on the evidence that addition of either GSH or NADPH increased the degradation of endosulfan.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.337-342
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• 2007

To obtain the data on the risk assessment of residue levels of organophosphorus and organochlorine pesticides in fresh ginseng and red ginseng extract, the residual pesticides in samples are surveyed with GC-NPD and GC-ECD for quantitative analysis and GC-MSD for qualitative analysis. The residual organophosphorus pesticides, such as diazinon, pyrimethanil, tolclofos-methyl, metalaxyl, diethofencarb, parathion, cyprodinil, tolylfluanid and kresoxim-methyl, are not detected in fresh ginseng from Punggi. The residual organophosphorus pesticides except tolclofos-methyl are not detected in fresh ginseng from Sangju. Average amount of tolclofos-methyl in fresh ginseng from Sangju are $0.054{\pm}0.008\;mg/kg$, representing $18{\pm}2%$ of MRL of 0.03 mg/kg on fresh ginseng in Korea. The residual organochlorine pesticides, such as BHC isomer, DDT isomer, aldrin, azoxystrobin, captan, cypermethrin, deltamethrin, dieldrin, difenoconazole, endosulfan-sulfate, endrin, fenhexamid, quintozene, ${\alpha}$-endosulfan and ${\beta}$-endosulfan, are not detected in fresh ginseng from Punggi and Sangju. The residual organophosphorus and organochlorine pesticides in red ginseng extract from Punggi and Sangju are not detected.

• 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.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.502-506
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• 2011

Most countries have the legislation and regulation for POPs control in food. In here, we studied the quantitative analysis of 24 organochlorine POPs (${\alpha}$-HCH 1, ${\beta}$-HCH 2, ${\gamma}$-HCH 3, ${\delta}$-HCH 4, trans-chlrodane 5, 2,4'-DDE 6, ${\alpha}$-endosulfan 7, cis-chlordane 8, 2,4'-DDD 9, endrin 10, ${\beta}$-endosulfan 11, 2,4'-DDT 12, endosulfan sulfate 13, HCB 14, aldrin 15, trans-nonachlor 16, 4,4'-DDE 17, dieldrin 18, 4,4'-DDD 19, cis-nonachlor 20, 4,4'-DDT 21, heptachlor 22, heptachlor epoxide 23 and mirex 24) with GC-ECD. The retention time of analytes were ranged between 19.18 min and 34.69 min, and their peak intervals were over 0.05 min at least. LOQs were ranged 0.003 ~ 0.033 ng/g, and their recovery rates were showed 60.9 ~ 120.8% on the 0.1 ng/g concentration of 24 organochlorine POPs. All tested 30 sundried salts were collected on Korean retailed market, and any analyte was not found in all the samples on LOQ levels.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.291-294
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• 2015

Persistent organic pollutants (POPs) including banned organochlorine pesticides, are found in Korean agricultural environments. Their translocation from agricultural environment to major crops has been reported. In this study, the POPs in 15 different agricultural waters of the Chungchung Province were monitored and all samples were prepared, followed by liquid-liquid fractionation and column chromatography prior to analysis using gas chromatography. Among pesticide-originated persistent organic pollutants, ${\alpha}$-endosulfan was determined in the range of 0.01 to 1.13 ng/mL. ${\beta}$-Endosulfan was determined in the range of 0.01 to 0.55 ng/mL, and endosulfan sulfate was ranged from 0.13 to 1.13 ng/mL. The total sum of endosulfans reached the range of 0.38 to 1.18 ng/mL. Three pesticides being used currently were also found in samples as 2.03-2.05 ng/mL for triadimefon, 0.26-0.33 ng/mL for tolyfluanid, and 1.34-3.85 ng/mL for chlorpyrifos. Taken together, endosulfans were introduced in the agricultural waters and their fates need continuous monitoring.

• Journal of Environmental Science International
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• v.14 no.2
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• pp.193-199
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• 2005

To obtain the residual organochlorine pesticides in the ginseng, the methods of multi-analysis for BHC's isomer, DDT's isomer and other organochlorine pesticides by GC-ECD are surveyed. The relative retention time for $\alpha-BHC,\;\beta-BHC,\;\delta-BHC\;and\;\gamma-BHC$ is 1.000, 1.025, 1.034 and 1.056, respectively. The relative retention time for o,p-DDE, p,p-DDE, o,o-DDD, o,p-DDT, o,p-DDD, and p,p-DDT is 1.199, 1.230, 1.242, 1.286, 1.329 and 1.333, respectively. The BHC isomers, DDT's isomer and other organochlorine pesticides are separated with multianalysis condition. The qualified defection concentration for $\alpha-BHC$, Quintozene, Aldrin, Captan, $\alpha-Endosulfan$, and Dieldrin is 0.95ng/g, 0.27ng/g, 1.04ng/g, 0.63ng/g, 0.55ng/g and 0.62ng/g, respectively. The qualified defection concentration for Fenhexamid, Endrin, $\beta-Endosulfan$, o,p-DDT, Endosulfan-sulfate is 5.71ng/g, 0.61ng/g, 0.48ng/g, 0.44ng/g and 0.51ng/g, respectively. BHC, Aldrin, Dieldrin, Endrin and DDT, which were Korea Food & Drug Administration advisory pesticides, are not detected in soil environment. Also it's residual organochlorine pesticides are not polluted in the ginseng on Sangju Korea.