• The Journal of Korean Society for School & Community Health Education
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• v.22 no.4
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• pp.49-60
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• 2021

Objectives: Laboratories have various latent physical, chemical, biological, and ergonomical factors according to the diversification and fusion of research and development activities. This study aims to investigate the chemical exposure concentrations of college laboratories and evaluate their health risks, and use them as basic data to promote the health of college students. Methods: The sampling and analysis of harmful chemicals in the air in laboratories were performed using Method 1500 of the U.S. National Institute for Occupational Safety and Health (NIOSH)의 Method 1500. The harmful chemicals in the laboratories were divided into carcinogenic and non-carcinogenic chemicals. Risk assessment was performed using the cancer risk (CR) for carcinogenic chemicals and using the hazard index (HI) for non-carcinogenic chemicals. Results: The harmful chemicals in college laboratories consisted of acetone, diethyl ether, methylene chloride, n-hexane, ethyl acetate, chloroform, tetrahydrofuran, toluene, and xylenes. They showed the highest concentrations in laboratories A (acetone 0.001~2.34ppm), B (chloroform 0.95~6.35ppm), C (diethyl ether 0.08~8.68ppm), and D (acetone 0.07~14.96ppm). The risk assessment result for non-carcinogenic chemicals showed that the HI of methylene chloride was 2.052 for men and 2.333 for women, the HI of N-hexane was 4.442 for men and 5.05 for women. Thus, the HI values were higher than 1. The risk of carcinogenic chemicals is determined by an excess cancer risk (ECR) value of 1.0×10^-5, which means that one in 100,000 people has a cancer risk. The ECRs of chloroform exceeded 1.0×10^-5 for both men and women, indicating the possibility of cancer risk. Conclusion: College laboratories showed the possibility of non-carcinogenic health risks for methylene chloride, n-hexane, tetrahydrofuran (THF), toluene, and xylenes, and carcinogenic health risks for chloroform, methylene chloride. However, this study used the maximum values of measurements to determine the worst case, and assumed that the subjects were exposed to the corresponding concentrations continuously for 8 hours per day for 300 days per year. In consideration of the nature of laboratory environment in which people are intermittently exposed, rather than continuously, to the chemicals, the results of this study has an element of overestimation.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.81-106
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• 1998

This study aims to point out what is the basic idea and principle of weed control in or-ganic farming. The korean organic agriculture gets a point in dispute on weed control, be-cause 1) they do not practice the Basic Standard of IFOAM and FAO/WHO Codex Guidelines(draft), and 2) Korean organic farming is defined quite differently from internationally recognized core aspects for organic agriculture. Organic farming, in Korea, is taken to mean just the replacement of chemical fertilizer by organic manure and a-voidance of agricultural chemicals without practicing on rotation, cropping system and so on. As a consequence, organic farmers in Korea are suffering from hard labor to control the weed. In the paper it is discussed on organical weed control method which are required in the Basic Standard of IFOAM and guidelined in the Organic Production Principles of FAO/WHO Codex draft, and furthermore the single or combination effect of those method are also discussed. In conclusion it is suggest the necessity, purpose, and effect of the introduction of the basic stan-dard to korean organic agriculture including organical weed control.

• Fire Science and Engineering
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• v.28 no.5
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• pp.71-79
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• 2014

This study was performed to test the combustive properties of Medium Density Fibreboards (MDFs) treated with chemicals of the bis-(dimethylaminomethyl) phosphinic acid (DMDAP), N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (DMDEDAP), piperazinomethyl-bis-phosphonic acid (PIPEABP), and methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP). MDFs were painted in three times with 15 wt% solution of the bis-(dimethylaminomethyl) phosphinic acid and alkylenediaminoalkyl-bis-phosphonic acids at the room temperature, respectively. After drying MDF treated with chemicals, combustive properties and volatile organic compounds (VOCs) contents were examined by the cone calorimeter (ISO 5660-1), test for flame retardant (NEMA Notice No. 2012034), and gas chromatography (KS M ISO 11890-2), respectively. It was indicated that the MDFs treated with chemicals showed the longer time to combustion time (CT) = (442~492) s than that of virgin plate by reducing the burning rate except for CT treated with DMDAP. In adition, the MDFs treated with chemicals showed both of the higher char area (44.33~61.33) kg/kg and char length (10.33~11.67) cm than those of virgin plate. Especially, the MDFs treated with chemicals showed the higher mean volatile organic compounds (VOCs) (0.188~0.333) g/L than that of virgin plate within the prescribed limits. Thus, It is supposed that the combustion- retardation properties were improved by the partial due to the treated chemicals in the virgin MDF.

• Analytical Science and Technology
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• v.26 no.1
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• pp.80-85
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• 2013

The sixty nine accident preparedness substances (APS) having high probability of chemical accident are controlled under the Toxic Chemicals Control Act (TCCA). Around the world, there has been a growing interest in the analysis of chemical warfare agent (CWAs). When a chemical accident occurs, it is generally required to detect and identify APS. However, the quantitative analytical data remain limited in Korea. In this study, an analytical method using GC/MS for volatile organic chemicals was established and a quantitative analysis method was studied. The calibration curve for 25 chemicals were obtained and 21 chemicals showed higher coefficient of determination ($r^2$ >0.998).

• Elastomers and Composites
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• v.35 no.1
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• pp.12-18
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• 2000

With growing concerns of environment and due to strengthening the government regulations on volatile organic compounds(VOC) the coatings industries are developing new technologies to reduce the amount of VOC released from coatings. In this study. a water soluble curing agent of amino-epoxy adduct was synthesized and its structure was identified by FT-IR, GPC and TG/DTA. The mechanical properties of the new curing agent in combination of KER-828 and KER-500 were investigated respectively. As an experimental result, the drying time of KER-828 was faster than that of KER-500 but the adhesion and impact strength of KER-500 was better than that of KER-828.

• Journal of Korean Society of Water and Wastewater
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• v.7 no.2
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• pp.9-23
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• 1993

Emission of hazardous and volatile organic chemicals from solid waste landfill site was become to important issue because of environmental pollution and health risk by such chemicals. Laboratory batch and continuous experiments were conducted respectively to elucidate isothermal sorption behaviors and transport phenomena(by gas through unsaturated solid waste layer) in wet solid waste-gas system. Source separated and size reduced refuse(bulky waste) and incinerated ash were used after controlling water content, and trichloroethylene(TCE) was chosen among many such chemicals because of it's generality among those man-created pollutants. Isothermal TCE sorption equilibria wet solid waste-gas system can be described in linear equation and partition coefficient in this system can be estimated approximately by the simple equation derived from schematic structure of the system. Transport equation modified by instantaneous equilibrium sorption fraction and kinetic sorption rate(overall mass transfer capacity coefficient) simulated well the column experiment results.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.343-353
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• 2016

Oligochaetes distribute widely in freshwater ecosystem, and some species are used as bioindicators for water quality assessment because they are tolerant to organic enrichment. They are acknowledged for potential for environmental health recovery of organic polluted environment. There are a lot of studies on ecology and toxicity assessment using oligochaetes in aquatic environment. In this study, we reviewed literature on ecotoxicology of aquatic oligochaetes. We searched literature from a database 'google scholar' by using keywords such as aquatic, oligochaete, and toxicity. The literature were summarized according to publication years, species, test methods, and chemicals. We obtained 133 articles published from 1953 to 2015 from the database. Among them, 58 papers(43.6% of total) have been published in 1990s. Three species(Lumnbriculus variegatus, Tubifex tubifex, and Limnodrilus hoffmeisteri) have been used most frequently in the study. Different species displayed different toxicological responses to different toxic chemicals. The results on the ecotoxicological study with aquatic oligochaetes revealed the possibility of the development for early warning system using aquatic oligochaetes to monitor aquatic ecosystem disturbance.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.1-12
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• 2019

Objective: Significant concerns have been raised over chemical exposure and potential health risks such as increased cancer mortality among laboratory workers. The aim of this study was to investigate the overall exposure and unit task exposure levels of researchers in organic synthesis laboratories at universities. Methods: Seventy-seven personal Time-weighted average(TWA) samples and 139 task-based samples from four organic synthesis laboratories at two universities were collected over three days. The concentrations of acetone, chloroform, dichloromethane(DCM), diethyl ether, ethyl acetate, n-hexane, tetrahydrofuran(THF), benzene, toluene, and xylene were determined using the GC-FID. Results: The most frequently used chemicals in the laboratories were acetone, DCM, n-hexane, methanol, and THF. Carcinogens such as benzene, chloroform, and DCM were used in one or more laboratories. The TWA full-shift exposures of researchers to acetone was the highest(ND-59.3 ppm). Benzene was observed above the occupational exposure limit in 18-40% of the samples. The levels of exposure to organic solvents were statistically different by task(p<0.05), while washing task was the highest. Washing was not perceived as a part of the real lab tasks. Rather it was considered as simple dish-washing or experimental preparation and performed in an open sink where exposure to organic solvents was unavoidable. TWAs and task-based concentrations were compared by substance, which suggests that TWA-based assessment could not reflect short-term and high concentration exposures. Conclusions: Laboratory workers may be exposed to various organic solvents at levels of concern. TWA-based measurement alone cannot guarantee holistic exposure assessment among lab workers as their exposures are very dependent on their tasks. Further investigation and characterization for specific tasks and overall chronic exposures will help protect lab workers from unnecessary exposure to chemicals while they perform research.

• Journal of Environmental Health Sciences
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• v.31 no.3
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• pp.207-214
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• 2005

Many Japanese today are suffering from health disorders related to their living environment, such as allergies and hypersensitivity to chemical substances. The Sick House/Building Syndrome has been a serious problem since 1996, due to low level exposure to hazardous chemicals such as formaldehyde and volatile organic compounds (VOCs) emitted in airtight houses. This paper aims to show current status of the syndrome in Japan and practical researches to promote prevention of, and improvement to indoor air pollution due to chemicals.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.143-167
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• 2005

Many Japanese today are suffering from health disorders related to their living environment, such as allergies and hypersensitivity to chemical substances. The Sick House/Building Syndrome has been a serious problem since 1996, due to low level exposure to hazardous chemicals such as formaldehyde and volatile organic compounds (VOCs) emitted in airtight houses. This paper aims to show current status of the syndrome in Japan and practical researches to promote prevention of, and improvement to indoor air pollution due to chemicals.