• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.1
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• pp.51-60
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• 2018

Objectives: Currently, there is only limited knowledge regarding the hazard of low-level exposure to CMR materials in workplaces. To overcome this limitation, a reference concentration for workers($RfC_w$) from among the risk assessment tools proposed by the US EPA is widely used to set a provisional workplace exposure level(PWEL) for CMR materials for which there are no established Korea Occupational Exposure Limits(KOELs) or subjective chemicals for work environment measurements as regulated by Korea Ministry of Employment and Labor(KMOEL). A simple European calculator of derived no effect level(SECO-DNEL) as proposed by REACH can also be used in place of $RfC_w$ to set the PWEL for chemicals. This study was performed to test the acceptability of using SECO-DNEL as an alternative to $RfC_w$ when setting a PWEL for low-level exposures. Methods: The $RfC_w$ and DNEL for the five CMR materials of dinitrogen oxide, catechol, 2-phenoxy ethanol, carbitol, and carbon black were calculated using the dose-response assessments of the US EPA for $RfC_w$ and REACH guidance for SECO-DNEL, respectively. They were compared using paired t-tests to determine the statistical differences between them. Results: For the five chemicals, the $RfC_w$ were 2.53 ppm, 0.10 ppm, 1.73 ppm, 1.66 ppm, and $0.05mg/m^3$, respectively, while the SECO-DNEL were 2.01 ppm, 0.11 ppm, 1.83 ppm, 1.77 ppm, $0.14mg/m^3$, respectively. There was no statistically significant difference between $RfC_w$ and SECO-DNEL. Conclusions: This study suggests that the SECO-DNEL could be applied in place of $RfC_w$ to set a PWEL for low-level exposure to chemicals, especially CMR materials. To further ensure the reliability of SECO-DNEL as an alternative tool, more chemicals should be applied for calculation and comparison with $RfC_w$.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.280-289
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• 2019

5-hydroxymethylfurfural (HMF) and its derivatives, 2,5-furandicarboxylic acid (FDCA) or 2,5-diformylfuran (DFF), are regarded as the "sleeping giants" owing to their wide range of applications and a good alternative source for the production of significant chemicals in almost all kind of industries. This mini-review briefly covers the aspects related to the syntheses, transformation, and applications for the biomass-derived platform chemicals from past to most recent. Many scientific efforts have continuously been made to find out the environmental benign applicable ways in order to achieve the full advantage of these renewable materials because of not only to protect the globe but also shield the future of new generations. One of the best solutions could be the development and utilization of platform chemicals from the natural biomass.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.3
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• pp.193-202
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• 2009

This study was done to assess an alternative method as a replacement of in vivo phototoxicity test. The human fibroblasts were exposed to several phototoxic chemicals (promethazine, chlorpromazine chlortetracycline, 8-methoxypsoralen, neutral red, bithionol) and non-phototoxic materials (cinnamic aldehyde, p-aminobenzoic acid, sodium lauryl sulfate, L-cysteine). The cell viability was measured by neutral red uptake (NRU) assay. The results of the NRU phototoxicity (PT) assay showed a close agreement with in vivo test except bithionol. We also have tested the cosmetic ingredients including $Medimin^{(R)}$ A, $Medimin^{(R)}$ D, $LG^{(R)}$ 106W, $Phytoclear^{(R)}$ EL-1, Carex humilis L. extract, Canna indica L. extract, Salvia miltiorrhira Bunge extract, $Parsol^{(R)}$ MCX and $Parsol^{(R)}$ 1789. Most materials except Salvia miltiorrhira Bunge extract did not show any phototoxicity.

• Carbon letters
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• v.1 no.3_4
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• pp.154-157
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• 2001

Composite adsorbents were prepared by mixing water plant sludge with phenolic resin having the ratio of 1 : 1, 1 : 2, and 1 : 3 respectively, curing from $100^{\circ}C$ to $170^{\circ}C$ under $N_2$ atmosphere, and then activating with $N_2$ at $700^{\circ}C$. Thermal property, specific surface area and morphology of the composite adsorbents as well as their precursors were measured by TGA, BET and SEM respectively. Removal efficiency of the composite adsorbents to ${NH_4}^+$ and TOC was compared with those of commercial zeolite and activated carbon. The adsorbents presented very promising TOC removal efficiency of 98%, which was identical level to that of commercial activated carbon while they displayed removal efficiency, only 32%, of ${NH_4}^+$. Therefore, this composite adsorbent considered as the alternative material of commercial activated carbon, used as an expensive removal agent of organic substances and THM in water treatment plant and it also suggested a possibility of practical application in other processes.

• Journal of environmental and Sanitary engineering
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• v.17 no.4
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• pp.39-46
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• 2002

The purpose of this research was to get an alternative idea about the situation and problems of domestic pest control company We performed a questionnaire survey of 105 companies to find the situation and problems of pest control companies with and with out lincensed sanitarians. The investigation revealed the following issues and the conclusions summarized. 1. Companies with lincensed sanitarians have shown to put forth hygenic safety(62%) as first priority as to companies without sanitarians neglect hygenic safety and rank financial benefit(40%) as their priority. 2. Companies with lincensed sanitarians have directions on its use of pesticides but the companies without inspectors rely only on field experiences. 3. Companies with lincensed sanitarians are known to use the safety equipment. To the contrary, companies without sanitarians worked without the proper safety equipment safety gear. 4. Companies with sanitarians been regularly received educational Programs on chemicals used in the pest control. And then companies without did not have my other educational programs for chemicals they used.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.194-194
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• 2001

Preclinical test methods for allergenic potential chemicals has been widely used to assess human risks and has been developed. Recently, the murine local lymph node assay (LLNA) has been proposed as a prospective method to identify contact allergens and to replace conventional the guinea pig maximization test (GPMT). The objective of this study was to establish LLNA and to evaluate allergenicity of chemicals by LLNA. (omitted)

• Journal of Forest and Environmental Science
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• v.25 no.3
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• pp.147-155
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• 2009

Higher plants provide valuable genetic assay systems for screening and monitoring environmental pollutants. They are now recognized as excellent indicators of mutagenic effects of environmental chemicals and are applicable for the detection of environmental mutagens both indoor and outdoor. 2,4-dichlorophenoxyacetic acid (2,4-D) is a herbicide commonly used in agriculture. The residues of 2,4-D are present in air, water, soil and edible plants. It constitutes a real hazard to the public health because it's wide spread use in agriculture. Genotoxic effects of 2,4-D on plant cells and potential of higher plants as a biomonitoring system for detecting chemical mutagens are evaluated. It is recommended that higher plant systems have been accepted by regulatory authorities as an alternative biomonitoring system for the detection of possible genetic damage resulting from pollution and the use of environmental chemicals.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1117-1123
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• 2019

Control of pine wilt disease, which is caused by pine wilt nematode Bursaphelenchus xylophilus, is heavily dependent on the use of chemicals such as abamectin. Although such chemicals are highly effective, demands for alternatives that are derived preferentially from natural sources, are increasing out of environmental concerns. One of the challenges to discovery of alternative control agents is lack of fast and efficient screening method that can be used in a high-throughput manner. Here we described the development of colorimetric assay for the rapid and accurate screening of candidate nematicidal compounds/biologics targeting B. xylophilus. Contrary to the conventional method, which relies on laborious visual inspection and counting of nematode population under microscope, our method utilizes a redox dye that changes its color in response to metabolic activity of nematode population in a given sample. In this work, we optimized parameters of our colorimetric assay including number of nematodes and amount of redox dye, and tested applicability of our assay for screening of chemicals and biologics. We demonstrated that our colorimetric assay can be applied to rapid and accurate quantification of nematode viability/mortality in a nematode population treated with candidate chemicals/biologics. Application of our method would facilitate high-throughput endeavors aiming at finding environment-friendly control agents for deadly disease of pine trees.

• Applied Microscopy
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• v.50
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• pp.10.1-10.6
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• 2020

Plant specimens for scanning electron microscopy (SEM) are commonly treated using standard protocols. Conventional fixatives consist of toxic chemicals such as glutaraldehyde, paraformaldehyde, and osmium tetroxide. In 1996, methanol fixation was reported as a rapid alternative to the standard protocols. If specimens are immersed in methanol for 30 s or longer and critical-point dried, they appear to be comparable in preservation quality to those treated with the chemical fixatives. A modified version that consists of methanol fixation and ethanol dehydration was effective at preserving the tissue morphology and dimensions. These solvent-based fixation and dehydration protocols are regarded as rapid and simple alternatives to standard protocols for SEM of plants.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.51-57
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• 2002

Cyanogenic glycosides are secondary plant metabolites that are known as plant defense chemicals. They are found in cassava, bamboo, flax, and other plants. In this paper, the role of cyanogenic glycosides, their characteristics, and their interactions with insects are discussed. Previous and current research in our laboratory found that several natural and synthetic cyanohydrins were effective against stored-product insects as fumigants. Due to their insecticidal activity to insects, cyanohydrins can be used as an alternative fumigant and also as soil fumigants. Risk assessment, however, should be done to account for possible environmental problems, non-target wildlife effects, and human health effects.