• Korean Journal of Environmental Agriculture
• /
• v.29 no.2
• /
• pp.176-183
• /
• 2010

Endosulfan degrading ability of Klebsiella oxytoca KE-8 immobilized by entrapment with activated carbon was examined. Endosulfan degradation by the immobilized bacterial strains on several different activated carbon based support materials was investigated. Based on results, activated carbon ($8\times30$ mesh) was chosen as a support material. The immobilized Klebsiella oxytoca KE-8 with the cell density of 4 mg $g^{-1}$ (dry weight) degraded 22.18 ug $ml^{-1}$ endosulfan within 5 days at pH 7.0, $30^{\circ}C$ in batch shake flask cultures. Also, we an experimented recycle packed bed column mode and continuous packed bed column mode for endosulfan degradation. Under optimum operation condition, the immobilized cells in a laboratory scale pack bed column with support beads were able to degrade endosulfan completely in defined minimal salt medium at a maximum rate of 129.6 ug $ml^{-1}$ per day. Moreover, the endosulfan degradation activity could be demonstrated at $4^{\circ}C$ for one month without significant decrease in activity. Results of this study suggest that immobilized cells of Klebsiella oxytoca KE-8 might be applicable to endosulfan contaminated site.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.13 no.2
• /
• pp.71-77
• /
• 2015

Purpose: Acute endosulfan poisoning is rare but causes significant morbidity and mortality. The aim of our study is to describe complications and features of seizure and determine factors associated with mortality in acute endosulfan poisoning. Methods: Twenty-eight adult patients with acute endosulfan poisoning admitted to our emergency department during a 15-year period were studied retrospectively. The clinical features of seizure, use of antiepileptic drugs during seizure, and hospital courses were evaluated. Clinical factors between survived group and non-survived group were compared for identification of factors associated with mortality. Results: Of the 28 patients with endosulfan poisoning, 4 patients (14.3%) died and 15 (53.6%) patients developed generalized tonic-clonic seizure. Thirteen patients (46.4%) and 5 patients (17.9%) progressed to status epilepticus (SE) and refractory status epilepticus (RSE), respectively. SE and RSE were associated with mortality. Almost all significant complications including shock, acute renal failure, hepatic toxicity, rhabdomyolysis, and cardiac injury developed in SE and RSE patients. Conclusion: SE and RSE were important contributors to death in endosulfan poisoning. Emergency physicians treating endosulfan poisoning should make an effort not to progress seizure following endosulfan poisoning to SE and RSE using a rapid and aggressive antiepileptic drug.

• Archives of Pharmacal Research
• /
• v.28 no.3
• /
• pp.351-357
• /
• 2005

Endosulfan is one of the organochlorine pesticides, which are well-known endocrine disruptors (EDs), and it acts as an estrogen agonist. Estrogen is a group of hormones that play an important role in mammary gland function and are implicated in mammary carcinogenesis. In the present study, we studied the effects of endosulfan on nodule like alveolar lesion (NLAL) formation in mouse mammary gland development using a mouse mammary gland organ culture (MMOC) system. Although endosulfan-treated mammary glands did not form NLALs, more alveolar buds were formed in this group than in the negative control (vehicle-treated) group. In addition, telomerase reverse transcriptase (TERT) mRNA expression levels were increased in endosulfan-treated mammary glands in a dose-dependent manner. Telomerase can be activated by estrogen, therefore, we examined the effects of endosulfan on telomerase activity, and found that the telomerase activity in estrogen receptor-positive MCF-7 cells was up-regulated by endosulfan treatment. Moreover, this activation was accompanied by the up­regulation of the TERT mRNA expression. Also, transient expression assays using CAT reporter plasm ids containing various fragments of the TERT promoter showed that this imperfect palindromic estrogen-responsive element is almost certainly responsible for the transcriptional activation by endosulfan. These results may help elucidate the endocrine disrupting mechanism of endosulfan.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2002.09a
• /
• pp.187-190
• /
• 2002

Reductive dechlorination of endosulfans was studied with zero valent metals (ZVMs) and bimetals in aqueous batch reactors. The effect of surfactants was evaluated. Endosulfan was successfully dechlorinated with zero valent iron. However, a bimetal, palladium coated iron (Pd/Fe) showed a highly enhanced reactivity for both endosulfan I and II indicating palladium act as a dechlorination catalyst on the iron. The effect of surfactants on degradation with ZVM has been very controvertible. Variable concentration of a nonionic surfactant, Triton X-100 and an anionic surfactant, SDS were added into the reactor with ZVM. The reaction rates of endosulfan were increased with both surfactants. In the case of Triton X-100, the reaction rate was increased with the increasing surfactant concentration up to 400 mg/L. Addition of small amount of surfactant under the CMC, the reaction rate was increased. However, the enhancing effect was diminished when a higher concentration of surfactant (1,000 mg/L) was used. Current study implicate that the surfactant adsorbed on the metal surface might increase the surface concentration of endosulfan resulting in the increased reaction rate. However, partitioning of endosulfan into the micelle formed at the high concentration of surfactant diminish the enhancing effect by reducing the contact chance between target compound and the metal surface.

• The Korean Journal of Pesticide Science
• /
• v.8 no.4
• /
• pp.280-287
• /
• 2004

We investigated the residual amounts of endosulfan and procymidone taken by vegetables grown in hydroponics culture and field conditions treated with the pesticides in order to evaluate safe cultivation concentration of the pesticides in the vegetables. Endosulfan and procymidone were selected as test pesticides because they have been reported to frequently detect in agricultural products at different concentrations. In hydroponic culture, by Chinese cabbage, procymidone was absorbed 3.8 times higher than endosulfan. The higher the pesticide concentration get, the worse the plant grew. In soil treated with 10 mg/kg of endosulfan, the pesticide absorbed by Leafy radish, Chinese cabbage and radish was less then their MRLs. In case of carlot, the residue level in soil which did not exceed its MRL was 1 mg/kg. The concentrations of procymidone in soil which did not exceed the MRLs in Leafy radish, Chinese cabbage, radish and carrot were 10, 10, 2 and 1 mg/kg, respectively Usually aged endosulfan and procymidone residues were less absorbed into crops than the fresh ones. Chinese cabbage absorbed more endosulfan and pocymidone than leafy radish, radish doing more than carrot.

• Journal of Food Hygiene and Safety
• /
• v.26 no.4
• /
• pp.403-409
• /
• 2011

The removal amount of pesticide residue which were remained in baechu (Chinese cabbage) and perilla leaf were measured during the preparation process of kimchi. The amounts of diazinon, procymidone and endosulfan applied to chinese cabbage were $9.18{\pm}0.03$mg/kg, $22.27{\pm}0.22$ and $10.46{\pm}0.02$ mg/kg respectively. When chinese cabbage was brined with 10% salt solution for 12 hours, the removal rates of three pesticides were 22.5%, 25.3% and 0.6% for diazinon, procymidone and endosulfan, respectively. When chinese cabbage was brined and rinsed 3 times with water, the removal rates of three pesticides were 69.9%, 85.6% and 11.2% for diazinon, procymidone and endosulfan, respectively. When kimchi was prepared and fermented for 28 days at $4^{\circ}C$, the removal rates of three pesticides were 79.4%, 94.4% and 21.0% for diazinon, procymidone and endosulfan, respectively. The relative percentages of removal dose of pesticides during brining were 28.4%, 26.9% and 3.2% for diazinon, procymidone and endosulfan, respectively and which were 59.7%, 63.8% and 50.4% during rinsing and which were 11.9%, 9.3% and 46.4% during fermentation, respectively. The amounts of diazinon, procymidone and endosulfan applied to perilla leaf were $18.11{\pm}0.62$ mg/kg, $31.80{\pm}0.33$ and $12.01{\pm}0.01$ mg/kg, respectively. When perilla leaf was rinsed 3 times with water, the removal rates of three pesticides were 60.5%, 52.0% and 23.7% for diazinon, procymidone and endosulfan, respectively. When perilla leaf was rinsed and brined with 10% salt solution for 14 days, the removal rates of three pesticides were 93.9%, 92.4% and 49.6% for diazinon, procymidone and endosulfan, respectively. The relative percentages of removal dose of pesticides during rinsing were 64.5%, 56.3% and 47.8% for diazinon, procymidone and endosulfan, respectively, and which during brining were 35.5%, 43.7% and 52.2% for diazinon, procymidone and endosulfan, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.26 no.4
• /
• pp.343-350
• /
• 2007

Three different experiments were carried out to investigate the runoff and erosion losses of endosulfan from sloped-field by rainfall. The mobility of endosulfan and which phase it was transported by were examined in adsorption study, the influence of rainfall pattern and slope degree on the pesticide loss were evaluated in simulated rainfall study, and the pesticide losses from soybean-grown field comparing with bare soil were measured in field lysimeter study. Adsorption parameter (K) of endosulfan ranged from 77 to 131 by adsorption method and K values by the desorption method were higher than those by the adsorption method. By the SSLRC's classification for pesticide mobility endosulfan was classified as non-mobile class ($K_{oc}>4,000$). Runoff and erosion loss of endosulfan by three rainfall scenarios ranged from 3.4 to 5.6%and from 4.4 to 15.6%of the amount treated. Endosulfan residues were mainly remained at the top 5 cm of soil depth after the simulated rainfall study. Pesticide loss in case of 30%-slope degree ranged from 0.6 to 0.9 times higher than those in case of 10%-slope degree. The difference of pesticide runoff loss was related with its concentration in runoff water and the difference of pesticide erosion loss would related closely with the quantity of soil eroded. Endosulfan losses from a series of lysimeter plots in sloped land by rainfall ranged from 5 to 35% of the amount treated. The erosion rate of endosulfan from soybean-plots was 66% of that from bare soil plots. The effect of slope conditions was not great for runoff loss, but was great for erosion loss as increasing to maximum $4{\sim}12$ times with slope degree and slope length. The peak runoff concentration of endosulfan in soybean-plots and bare soil plots ranged from 8 to 10 and from 7 to $9{\mu}gL^{-1}$ on nine plots with different slope degree and slope length. Therefore the difference of the peak runoff concentrations between bare soil plots and soybean-plots were not great.

• Korean Journal of Environmental Agriculture
• /
• v.20 no.5
• /
• pp.305-309
• /
• 2001

Thirty-day-old rice seedlings, IR-20 variety were transplanted into the experimental plots and were sprayed with endosulfan (35% EC) after 52 days at the rate of 0.64 kg a.i/ha. Residues of endosulfan in the plant, soil, and water were found to decrease steadily upto 15 days. A second application of the pesticide was made on the 31st day and the plant was harvested on 56th day after the first application. The residue level on hay and grains was 0.7 ${\mu}g/g$. This level is seven times higher than FAO/WHO-prescribed tolerance level of 0.1 ${\mu}g/g$. Metabolites of endosulfan were traced out in plants, soil, and water during the pre- and post-harvest period.

• The Korean Journal of Pesticide Science
• /
• v.15 no.2
• /
• pp.160-165
• /
• 2011

Monitoring of pesticide residues were conducted at three sites in the Southern Area of Seoul, Korea (Gang-nam, Gang-dong and Song-pa). We measured pesticide residues within soil samples using multi-pesticide residues analysis. Samples were collected at the three sites with 60 sampling spots. The amount of pesticide residues in the soil samples were as follows [(minimum-maximum), mg/kg] endosulfan 0.002-0.999, procymidone 0.002-1.200, diazinon 0.003-0.024, metalaxyl 0.012-0.075. In soil treated with 0.445 mg/kg of endosulfan, the pesticide absorbed by chamnamul, was 0.157 mg/kg (Absorption rate : 35.3%). However, in soil treated with 0.358 mg/kg of endosulfan, the pesticide absorbed by lettuce, was 0.004 mg/kg (Absorption rate : 1.1%).

• The Korean Journal of Pesticide Science
• /
• v.16 no.2
• /
• pp.145-150
• /
• 2012

This study was carried out to investigate the degradation of six residual pesticides (${\alpha}$- and ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole, EPN) in red pepper powder after ultraviolet (UV) irradiation. The residual ratio of pesticides after 365 nm irradiation which distance is 20 cm and irradiation time is 5 minutes were 73.4, 69.6, 60.8, 92.7, 73.8 and 90.5% in ${\alpha}$-Endosulfan, ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole and EPN, respectively. The residual ratio of pesticides after 254 nm irradiation which distance is 5 cm and irradiation time is 36 hours were 74.6, 64.5, 71.1, 79.1, 79.4 and 64.7% in ${\alpha}$-Endosulfan, ${\beta}$-Endosulfan, Cypermethrin, Fenitrothion, Hexaconazole and EPN, respectively.