• 대한임상독성학회지
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• 제6권2호
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• pp.83-90
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• 2008

Organophosphate (OP) pesticides are the most common source of human toxicity globally, causing high mortality and morbidity despite the availability of atropine as a specific antidote and oximes to reactivate acetylcholinesterase. The primary toxicity mechanism is inhibition of acetylcholinesterase (AchE), resulting in accumulation of the neurotransmitter, acetylcholine, and abnormal stimulation of acetylcholine receptors. Thus, the symptoms (muscarinic, nicotinic, and central nervous system) result from cholinergic overactivity because of AchE inhibition. OP can also cause rhabdomyolysis, pancreatitis, parotitis, and hepatitis. OP therapy includes decontamination, supportive therapy, and the use of specific antidotes such as atropine and oximes. However, there has been a paucity of controlled trials in humans. Here we evaluated the literature for advances in therapeutic strategies for acute OP poisoning over the last 10 years.

• 대한화학회지
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• 제57권3호
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• pp.382-388
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• 2013

The present paper focuses on the synthesis, characterization and application of nanophotocatalyst for degradation of quinalphos and monocrotophos. Novel heterostructured ZnO/$TiO_2$ photocatalyst ($Z_9T$) was prepared and characterized with X-ray diffraction (XRD), SEM and UV-vis diffuses reflectance spectroscopy. The average crystalline size of synthesized $Z_9T$ was found to be 21.48 nm. The pesticides were degraded in the presence of nanophotocatalysts i.e., $TiO_2$, ZnO, $TiO_2$/ZnO mixed in various proportions and heterostructured nanophotocatalyst synthesized by Sol-Gel method. The batch experiments were performed by adding photocatalyst to 100 ml of pesticide solution and suspension was subjected to irradiation under UV light. In case of mixed catalyst, the maximum degradation of monocrotophos and quinalphos has been observed when ZnO and $TiO_2$ were in the ratio of 7:3 and 8:2 respectively. The degradation efficiency with synthesized heterostructured nanophotocatalyst ($Z_9T$) was found to be comparable with $TiO_2$.

• BioChip Journal
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• 제12권4호
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• pp.326-331
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• 2018

Contamination by pesticides is an everincreasing problem associated with fields of environmental management and healthcare. Accordingly, appropriate treatments are in demand. Pesticide detection methods have been researched extensively, aimed at making the detection convenient, fast, cost-effective, and easy to use. Among the various detecting strategies, paper-based assay is potent for real-time pesticide sensing due to its unique advantages including disposability, light weight, and low cost. In this study, a paper-based sensor for chlorpyrifos, an organophosphate pesticide, has been developed by layering three sheets of patterned plates. In colorimetric quantification of pesticides, the blue color produced by the interaction between acetylcholinesterase and indoxyl acetate is inhibited by the pesticide molecules present in the sample solutions. With the optimized paper-based sensor, the pesticide is sensitively detected (limit of detection =8.60 ppm) within 5min. Furthermore, the shelf life of the device is enhanced to 14 days after from the fabrication, by treating trehalose solution onto the deposited reagents. We expect the paper-based device to be utilized as a first-screening analytic device for water quality monitoring and food analysis.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권6호
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• pp.436-440
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• 2000

Recently, we reported an improved technology for the degradation of organophosphate nerve agents using whole cells of genetically engineered Escherichia coli that anchored and displayed the enzyme organophosphorus hydrolase on the cell surface. In this paper we report the immobilization of these cells on highly porous sintered glass beads and the subsequent application of the immobilized cell in a continuous-flow packed bed bioreactor for the biodetoxification of a widely used insecticide, coumaphos.

• Safety and Health at Work
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• 제4권1호
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• pp.1-11
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• 2013

This review surveys the recent literature on the neurodevelopmental impacts of chemical exposures during pregnancy. The review focuses primarily on chemicals of recent concern, including phthalates, bisphenol-A, polybrominated diphenyl ethers, and perfluorinated compounds, but also addresses chemicals with longer histories of investigation, including air pollutants, lead, methylmercury, manganese, arsenic, and organophosphate pesticides. For some chemicals of more recent concern, the available literature does not yet afford strong conclusions about neurodevelopment toxicity. In such cases, points of disagreement among studies are identified and suggestions provided for approaches to resolution of the inconsistencies, including greater standardization of methods for expressing exposure and assessing outcomes.

• Journal of Applied Biological Chemistry
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• 제61권4호
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• pp.411-416
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• 2018

Chlorpyrifos (CPF) is one of the most heavily used organophosphate pesticides and is useful as an insecticide drug. However, CPF also causes toxic effects in nontarget organisms, including humans and animals. Jageum-Jung (JGJ) is a traditional oriental medicine, composed of five specific herbs with antioxidant and hepatoprotective properties, used for detoxification. In the present study, highly concentrated CPF was orally administrated to male Institute of Cancer Research mice to produce acute toxicity, and the protective effects of JGJ administration were investigated through statistical analysis of changes in body and organ weights and serum biochemical parameters. JGJ caused body and organ weights to recover and reduced the levels of serum biochemical parameters indicative of liver damage, such as glutamic oxalate transaminase, glutamic pyruvate transaminase, alkaline phosphatase, lactic dehydrogenase, urea, glucose, total cholesterol, and triglyceride, that had been increased by CPF treatment. Our results demonstrated that JGJ ameliorates the effects of acute chlorpyrifos-induced toxicity. Therefore, JGJ has the potential to be used as a traditional medicine to alleviate insecticide toxicity.

• 대한의생명과학회지
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• 제22권4호
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• pp.140-149
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• 2016

All pesticides must be assessed strictly whether safe or not when agricultural operators are exposed to the pesticides in farmland. A pesticide is commonly regarded as safe when estimated dermal absorption amount is lower than the acceptable operator's exposure level (AOEL). In this study, dermal absorption rate of chlorpyrifos, a widely used organophosphate insecticide, was investigated using rat dermal tissue model. Chlorpyrifos wettable powder solved in water (250, 500 and 2,500 ppm) was applied to freshly excised rat dermal slices ($341{\sim}413{\mu}m$ thickness) on static Franz diffusion cells at $32^{\circ}C$ for 6 hours. After exposure period of 6 hours, and then washing-at residual amount of chlorpyrifos was analyzed in dermal tissues, tape strips, washing solution, washing swabs of receptor bottles and receptor fluids at 1, 2, 4, 8 and 24 hours. Chlorpyrifos was only detected in dermal tissue but not found in receptor fluid at each concentration and time point, and the absorption rate of 250, 500 and 2,500 ppm was 2.36%, 1.96% and 1.69%, respectively. The estimated exposure level of chlorpyrifos was calculated as 0.012 mg/kg bw/day. The health risk for farmers in this condition is a level of concern because the estimated exposure level is 12 times higher than AOEL 0.001 mg/kg bw/day. However, actual health risk will be alleviated than estimated because absorbed chlorpyrifos is not permeated into internal body system and only retained in skin layer.

• Environmental Analysis Health and Toxicology
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• 제25권4호
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• pp.263-271
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• 2010

Objectives : The records of 447 pesticide poisoning deaths from the National Forensic Service (NFS) headquarters located in Seoul of Korea from 2005 to 2009 were retrospectively reviewed. Methods : The data of each case were analyzed by using the SPSS program. Results : The mean age was $57.8{\pm}14.8$ years and the range was 16-92 years. The numbers of deaths of males and females were 301 and 134, respectively. The largest number of cases occurred in people aged 50-59 years (n=92, 20.6%) followed by the age groups 40-49 years (n=91, 20.4%), 60-69 years (n=88, 19.7%), and 70-79 years (n=75, 16.8%). The total number of deaths among other age groups (10-19, 20-29, 30-39, 80-89, and 90-99 years) was 73, representing only 16.3%. Of all pesticide poisoning deaths, 96.2% were due to suicide, and 28.4% of the total number who died received medical treatment. The mostfrequent site of ingestion was the person's own residence (n=279, 62.4%). The most common classes of pesticide were bipyridylium herbicide (paraquat, 31.1%), organophosphate insecticide (21.7%), and carbamate insecticide (15.4%). The major pesticides having a high proportion of fatalities were paraquat (31.1%), methomyl (11.4%), glyphosate (9.1%), dichlorvos (5.6%), phosphamidon (4.6%), and methidathion (4.0%). Conclusions : This study showed that poisoning deaths due to pesticides are one of the major public health problems in Korea. Enforcement of regulations and safety education to prevent pesticide poisoning should be carried out by the government.

• 대한임상독성학회지
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• 제16권1호
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• pp.1-8
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• 2018

Purpose: Extremely hazardous pesticides are classified as World Health Organization (WHO) hazard class Ia. However, data describing the clinical course of WHO class Ia OP (organophosphate) poisonings in humans are very scarce. Here, we compare the clinical features of patients who ingested hazard class Ia OPs. Methods: This retrospective observational case study included 75 patients with a history of ingesting ethyl p-nitrophenol thio-benzene phosphonate (EPN), phosphamidon, or terbufos. The patients were divided according to the chemical formulation of the ingested OP. Data regarding mortality and the development of complications were collected and compared among groups. Results: There were no differences in the baseline characteristics and severity scores at presentation between the three groups. No fatalities were observed in the terbufos group. The fatality rates in the EPN and phosphamidon groups were 11.8% and 28.6%, respectively. Patients poisoned with EPN developed respiratory failure later than those poisoned with phosphamidon and also tended to require longer mechanical ventilatory support than phosphamidon patients. The main cause of death was pneumonia in the EPN group and hypotensive shock in the phosphamidon group. Death occurred later in the EPN group than in the phosphamidon group. Conclusion: Even though all three drugs are classified as WHO class Ia OPs (extremely hazardous pesticides), their clinical courses and the related causes of death in humans varied. Their treatment protocols and predicted outcomes should therefore also be different based on the chemical formulation of the OP.

• 농업과학연구
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• 제50권4호
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• pp.941-952
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• 2023

The metabolites of agrichemicals, such as organophosphorus pesticides, are known to be more hazardous than their parent pesticides. 3,5,6-trichloro-2-pyridinol (TCP) is a major degradation product of chlorpyrifos, one of the organophosphate insecticides widely used in agriculture. In vivo or in vitro exposure to chlorpyrifos has been known to interfere with male reproductive functions, leading to reduced fertility in mammals. Therefore, this study was performed to examine the changes in the fertilization competence of boar spermatozoa exposed to TCP. Sperm samples were subjected to varying concentrations of TCP (10, 50, 100, 200 µM) and different periods of incubation. Sperm motility, motion kinematics, viability, acrosome integrity, intracellular reactive oxygen species (ROS) production, and gene expression levels (ODf2, ZPBP2, AKAP3 and AKAP4) were evaluated after exposure of the sperm to TCP. A significant dose-dependent reduction in motility was observed in sperm samples incubated with TCP compared to the controls after both incubation periods. Sperm viability was significantly decreased in samples incubated with 50, 100, and 200 µM TCP in both incubation periods. A significantly lower percentage of normal acrosomes and gene expression levels were observed in sperm samples exposed to 50, 100, and 200 µM TCP after both incubation periods, compared to the controls. There was a significant increase in the ROS production in spermatozoa incubated with 100 - 200 µM TCP after both incubation periods. Consequently, the direct exposure of boar spermatozoa to TCP interferes with sperm functions and leads to decreased fertilization. In order to identify and address the various causes of reproductive decline, the impact of chemical metabolites needs to be discussed in depth.