• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.23-37
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• 2017

Objectives : This study was conducted to evaluate the level of exposure to volatile organic compounds (VOCs) among workers handling rust preventive oils. Methods : A total of 30 bulk samples and 54 personal air samples were collected using diffusive samplers at 22 workplaces handling rust preventive oils in Daegu and Gyongsangbuk-do Province from March to October 2013. We also investigated detailed information on the related work conditions, such as kinds of products, handling methods, local exhaustive ventilation systems, and the status of the wearing personal protective equipment. All bulk samples and air samples were analyzed using gas chromatography mass spectrometry (GC-MS) to identify components to which workers potentially were exposed. Quantitative airborne concentrations of VOCs were confirmed using gas chromatography with flame ionized detectors. Results : In terms of qualitative analyses for the 30 bulk samples, we found carcinogenic, mutagenic and reproductive toxic(CMR) substances such as butane(carcinogenic Group 1A, mutagenic Group 1B), butoxy ethanol(carcinogenic Group 2), cumene (carcinogenic Group 2), ethyl benzene(carcinogenic Group 2), methyl isobutyl ketone(carcinogenic Group 2) and toluene (reproductive toxic, Group 2). As a result of full-shift based personal air samples, eight substances such as n-hexane, n-heptane, octane, nonane, decane, toluene, ethyl benzene and xylene were detected. Among them, n-hexane and n-heptane were detected in all of 54 air samples with $13.13mg/m^3$ and $8.61mg/m^3$ of maximum concentration, respectively. The level of airborne concentration from all of samples were bellow the occupational exposure limit in Korea. Conclusions : Based on the results of this study, workers handling rust preventive oils could be exposed to CMR substances contained in rust preventive oils and n-hexane and n-heptane were found as the most frequent sources of VOC exposure.

• Journal of Preventive Medicine and Public Health
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• v.41 no.6
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• pp.397-406
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• 2008

This paper reviews the published literature that is concerned with color vision impairment from industrial and environmental exposure to neurotoxic substances, and we evaluated whether testing for color vision impairment could be an affordable procedure for assessing these neurotoxic effects. In general, most cases of congenital color vision impairment are red-green, and blue-yellow impairment is extremely rare. However, most of the acquired color vision impairment that is related to age, alcohol or environmental factors is blue-yellow impairment. Therefore, many studies have been performed to identify this relationship between exposure to neurotoxic substances, such as organic solvents and heavy metals, and the prevalence of blue-yellow color vision impairment. The test for color vision impairment is known to be very sensitive to the early signs of nervous system dysfunction and this can be useful for making the early diagnosis of neurotoxic effects from exposure to very low concentrations of toxic substances.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.135-136
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• 2020

Recently, there is a problem that is most important in constructing buildings and building materials. It is a harmful substance generated in buildings. These harmful substances are CO₂, radon and formaldehyde, volatile organic compounds generated from building materials. These are bad for the human body, may have a negative effect and cause large illnesses such as cancer. Recently built apartments have a high density, so there is a problem that harmful substances do not escape well. As a result, people's interest in indoor air quality is growing and in order to solve this problem and various researches are being conducted on the materials used for concrete pouring to find out how much the materials used adsorb harmful substances. this study uses carbon black as a material that can adsorb these harmful substances. The purpose of this study is to measure the bending strength, compressive strength, and to determine whether the paste containing carbon black can improve indoor air quality.

• Journal of Environmental Policy
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• v.13 no.2
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• pp.65-98
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• 2014

Plastics of the marine environment are broken gradually down into smaller particles by chemical weathering, called "microplastic". Microplastics absorb organic pollutants that are persistent bioaccumulative substances. If marine animals ingested microplastic added to contaminant, it will lead to a bioaccumation through the food web. It eventually destroy health of marine environment and is harmful to marine top predators including humans. Also, Microplastics can impact marine animals by leaching the endocrine disruptor in microplastic itself as well as playing an adsorbent role of organic pollutants. Persistent and bioaccumulative substances in Korea have been regulated in terms of chemical risk but existing regulations largely have been limited in land-based source management of microplastic. Thus, the harmful impact will be increased whether the microplastics absorbed contaminants. To prevent risk of persistent bioaccumulative substances, this study suggests the following: (1) the strict management of microplastic by designating the hazardous substances, (2) expand the use of biodegradable plastic, (3) the effort for reuse and recycle, (4) the expand of microplastic clean-up programs.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.289-298
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• 1987

This study was conducted to investigate the presence of biologically active substances such as phenolic acids, fatty acids and organic acids in the medical plants like Kalopanax pictum and Acanthopanacis cortex. Alcohol extracts of K. pictum and A. cortex showed complete inhibition of lettuce seed germination, indicating that these plants contained the biologically active substances. Eleven phenolic acids including protocatechuic acid were identified from K. pictum and A. cortex by GLC, and the contents of total phenolic acid were 1.7917mg/g in K. pictum, and 0.9567mg/g in A. cortex. Polyphenols such as neochlorogenic acid, chi orogenic acid, scopoletin, rutin and kaempferolglycoside which were not detected by GLC were anayzed by HPLC, and among phenolic acids indentified chi orogenic acid seemed to be the major acid in both K. pictum and A. cortex presented in amount of 23.7 and 13.0ppm, respectively. K. pictum contained 5.26mg/g of fatty acids and 27.69mg/g of organic acids, and A. cortex possessed 3.22mg/g of fatty acids and 9.80mg/g of organic acids, linoleic and oxalic acid appeared to be the major fatty and organic acids, representing more than 50% of total fatty acids and 80% of total organic acids.

• Analytical Science and Technology
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• v.24 no.5
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• pp.395-400
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• 2011

This study has been carried out in order to effectively manage three groups of unregulated hazardous organic substances (PCDD/DFs, PAHs, PCBs) in South Korea. The investigated substances have been analyzed according to the test methods for hazardous substances in specified wastes provided by the National Institute of Environmental Research, Korea. Total contents of the organic compounds have been determined for hazardous wastes from three major industrial categories (paint, iron removal, steelmaking), such as waste organic solvent, waste paint or dust. By investigating the waste samples for 7 PAHs using GC/MSD, Naphthalene has been detected (N.D~1631.33 mg/kg). The highest Naphthalene concentration, which exceeded the korean marine dumping waste standard, was found in waste organic solvents and waste paints. Although a content analysis of 7 PCB isomers has been conducted, none of these compounds was detected. The analysis of PCDD/DFs has revealed that all samples meet the criterion for low POP content defined in the technical guidelines developed under the Basel Convention. The PCDD/DFs content in dust samples deriving from 10 manufacturing processes (billet, bloom) was determined to be in the range of N.D~5.66 ng I-TEQ/g waste.

• Journal of Korean Society on Water Environment
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• v.30 no.2
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• pp.175-183
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• 2014

The influence of temperature on the treatment efficiency of chlorinated organic substances contained in groundwater by permeable reactive barrier which is composed of $Fe^{\circ}$ has been investigated by constructing the Pourbaix diagrams for Fe-$H_2O$ system at different temperatures based on thermodynamic estimation. In aerobic condition, the equilibrium potentials for $Fe^{\circ}/Fe^{2+}$ and $Fe^{2+}/Fe^{3+}$ were observed to increase, therefore, the dechlorination reaction for organic pollutants by $Fe^{\circ}$ was considered to decline with temperature due to the diminished oxidation of reactive barrier. The result for the variations of the ionization fraction of $Fe^{2+}$ and $Fe^{3+}$ ion in the pH range of 0 ~ 2.5 obtained by employing Visual MINTEQ program showed that the ionization fraction of $Fe^{2+}$ increased with pH, however, that of $Fe^{3+}$ decreased symmetrically and the extent of the variation of ionization fraction for both ions was raised as temperature rises. The equilibrium pH for $Fe^{3+}/Fe(OH)_3$ was examined to decrease with temperature so that the treatment efficiency of chlorinated organic substance was expected to decrease with temperature due to the enhanced formation of passivating film in aerobic condition. The change of the reactivity of a specific chemical species with temperature was defined quantitatively based on the area of its stable region in Pourbaix diagram and depending on this the reactivity of $Fe^{3+}$ was shown to decrease with temperature, however, that of $Fe(OH)_3$ was decreased monotonously as temperature is raised for $Fe^{3+}/Fe(OH)_3$ equilibrium system. In anaerobic condition, the equilibrium potential for $Fe^{\circ}/Fe^{2+}$ was observed to rise and the equilibrium pH for $Fe^{2+}/Fe(OH)_2$ were examined to decrease as temperature increases, therefore, similar to that for aerobic condition the efficiency of the dechlorination reaction for organic substances was considered to be diminished when temperature rises because of the reduced oxidation of $Fe^{\circ}$ and increased formation of $Fe(OH)_2$ passivating film.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.4
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• pp.481-491
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• 2022

This study investigates the characteristics of the GAC adsorption behavior during the operation of a multi-stage cross-flow filtration and GAC adsorption process for the purpose of devising an advanced treatment of combined sewer overflows (CSOs) and evaluates the regeneration efficiency of spent GAC that has reached the design breakpoint. During the filtration process, suspended substances are easily removed, but dissolved organic substances are not removed, necessitating a process capable of removing dissolved organic substances for the advanced treatment of CSOs. In general, GAC adsorption has been applied under low-concentration organic conditions, such as for water purification and tertiary treatments of sewage, and has rarely been applied under conditions with high organic concentrations, such as with sewage or CSOs. Accordingly, this study will provide a new and interesting experience. Also in this study, the continuous operation and breakthrough characteristics of GAC according to the strength of the inflow organic matter were investigated, electrochemical regeneration was applied to the used GAC, and the regeneration efficiency was evaluated through desorption and re-adsorption tests. The results showed that the breakthrough period was 21 days under high concentration conditions, 28 days at medium concentrations, and 32 days under low concentration conditions. The desorption of adsorbed organic matter through electrolysis occurred in the range of 188 to 609 mgCOD/L depending on the electrolysis conditions, and the effect of the electrolyte type led to the finding that NaOH was slightly higher than H₂O₂.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.488-499
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• 2019

Objectives: This study was conducted to identify the characterization of organics solvent exposure among painting workers in the shipbuilding painting process, especially for their daily variations(within worker variance). Methods: Charcoal passive dosimeters were worn throughout each work shift for 20 days for five painting workers from October 19 to November 26, 2015. A total of 100 samples were collected, analyzed and compared with statutory workplace environmental measurements. Results: The geometric mean(GM) and geometric standard deviation(GSD) of mixed organic solvent(six substances) exposure index(EI) for the 100 samples were 0.42 and 4.42 respectively. The median and range of GSD for within worker EI representing five workers' daily EI variation is 3.72 and 2.63 ~ 5.20, respectively, which is classified as a very large variation(GSD>3). We were able to divide the painting process into two similar exposure groups(SEGs), Touch-up and Spray. Spray painting workers were much more exposed to organic solvent than Touch-up painting workers(GM=0.71 vs. 0.19), but less variably (GSD=3.64 vs. 4.10). xylene is the substance to which the workers were most exposed(GM=16.19 ppm, GSD=4.36), and the exposure characteristics of six substances including xylene is similar to those of EI. Conclusions: The daily variation of organic solvent exposure in the shipbuilding painting process is so high that statutory Assessment of Reliability of Work Environment Monitoring needs to be conducted with statistically sufficient number of samples and evidence.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.755-764
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• 2000

Fate and transport of hydrophobic organic contaminants can be influenced by naturally-existing humic substances and surfactants applied to wash polluted soils in the subsurface environment. The objective of this paper is to study the solubility enhancement of four PAHs (polycyclic aromatic hydrocarbon) and p,p'-DDT in humic acid and surfactant solutions. As the number of aromatic ring is increased, the extent of solubility enhancement of PAHs by humic acid increased. Although the hydrophobicity of p,p'-DDT was the largest among five organic compounds used, the extent of solubility enhancement of p,p'-DDT by humic acid was lower than that of pyrene. In case of anionic surfactants, the extent of the increased solubility of five organic compounds by SDS and SDDBS was increased linearly, but the extent of the increased solubility of p,p'-DDT by MADS-12 was lower than that of perylene.