• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.21-26
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• 2019

Objective: The aim of this study is to analyze an excess trend for domestic permissible exposure limit of trichloroethylene based on previous literature review. Materials and Methods: The research object is a trichloroethylene among 13 chemical substances regulated with PEL(Permissible Exposure Limit) in Occupational Safety and Health Act. The information utilized from this study is the work environment measurement data from 2004 to 2013. The highest level among concentration data measured at various workplaces was selected as a representative value through data process. N.D. (Not Detected) data was considered as 1/2 of LOD(Limit Of Detection). Results: Among work environment measurement data between 2004 and 2013, the highest number of excess workplace and excess rate(24 sites & 1.15%) was observed in 2008's data when applying the PEL(50 ppm) of trichloroethylene. When they are compared with the ACGIH's TLV-TWA(10 ppm), 2008's data showed the highest number of excess workplace and excess rate(175 sites & 8.37%). The number of excess workplace and excess rate related to PEL of trichloroethylene showed increase trend in 2005 but tended to decrease after 2008. Conclusions: Based on the results obtained from this study, the exposure level of trichloroethylene in case of domestic workers is not considered as a safe phase regardless of the year of work environment measurement year. Thus, a strictly preventive management in workplace should be provided for reducing exposure level of trichloroethylene.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1035-1040
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• 1999

Photocatalytic degradation of trichloroethylene has been carried out with UV-illuminated $TiO_2$-coated pyrex reactor in gas phase. Three commercial $TiO_2$ oxides were used as catalysts. The effect of reaction conditions, initial concentration of trichloroethylene, concentration of oxidant and light intensity on the photocatalytic activity were examined. Anatase-type catalyst showed higher activity than rutile-type, but P-25 catalyst showed the highest activity. The degradation rate increased with the decrease of flow rate and initial trichloroethylene concentration. It was preferable to use air as an oxidant. In addition, reactants with the water vapor decreased the activity and the degradation rate increased with the increase of light intensity, but it was very low with solar light. Photocatalytic deactivation was not observed at low concentration of trichloroethylene.

• Journal of Life Science
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• v.12 no.5
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• pp.561-565
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• 2002

Pseudomonas sp. EL-041 was previously isolated from phenol-acclimated activated sludge. This bacterium was capable of degrading phenol and cometabolizing trichloroethylene (TCE). In this study, we report the identification of trichloroethylene- degrading enzyme in Pseudomonas sp. EL-041 by the investigation of enzyme activity and DNA sequencing of specific phenol oxygenase gene. As the results of experiment, trichloroethylene-degrading enzyme in Pseudomonas sp. EL-041 was monooxygenase and suspected to phenol hydroxylase.

• Toxicological Research
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• v.28 no.3
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• pp.173-178
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• 2012

This study investigated the human health risks of trichloroethylene from Industrial Complex A. The excessive carcinogenic risks for central tendency exposure were $1.40{\times}10^{-5}$ for male and female residents in the vicinity of Industrial Complex A. The excessive cancers risk for reasonable maximum exposure were $2.88{\times}10^{-5}$ and $1.97{\times}10^{-5}$ for males and females, respectively. These values indicate that there are potential cancer risks for exposure to these concentrations. The hazard index for central tendency exposure to trichloroethylene was 1.71 for male and female residents. The hazard indexes for reasonable maximum exposure were 3.27 and 2.41 for males and females, respectively. These values were over one, which is equivalent to the threshold value. This result showed that adverse cancer and non-cancer health effects may occur and that some risk management of trichloroethylene from Industrial Complex A was needed.

• Bioindustry News
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• v.13 no.2
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• pp.18-29
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• 2000

• Clean Technology
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• v.8 no.2
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• pp.93-99
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• 2002

Adsorption dynamics for toluene and trichloroethylene with an isothermal fixed bed of activated carbon fiber were investigated. Equilibrium isotherms were measured by a static method for toluene and trichloroethylene onto activated carbon fiber at temperatures of 298, 323, and 348 K and pressure up to 3 kPa for toluene and 6 kPa for trichloroethylene, respectively. These results were correlated by the Toth equation. And dynamic experiments in an isothermal condition of 298 K were examined. Breakthrough curves reflected the effects of the experimental variables such as partial pressures for adsorbate and interstitial bulk velocities of gas flow. To present the column dynamics, a dynamic model based on the linear driving force (LDF) mass transfer model was applied.

• Journal of Environmental Science International
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• v.10 no.2
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• pp.99-103
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• 2001

Several microorganisms which degrade phenol and trichloroethylene(TCE) were isolated from the activated sludge of a wastewater treatment plant. Among them, one isolate EL-04J showed the highest degradability and was identified as a Pseudomonas species according to morphological, cultural and biochemical properties. The phenol-induced cells of Pseudomonas EL-04J, which were preincubated in the mineral salts medium containing phenol as a sole carbon source, degraded 90% of 25$\mu$M TCE within 20h. This strain could also utilize some of methylated phenol derivatives (o-cresol, m-cresol and p-cresol) as the sole source of carbon and energy. Cresol-induced cells of Pseudomonas EL-04J also cometabolized TCE.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.1
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• pp.3-5
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• 2023

Objective: This study introduces exposure concentrations of time-weighted average standard (TWA) evaluation and short-time exposure standard (STEL) evaluation for trichloroethylene in the cleaning process. Methods: Trichloroethylene measurement was conducted according to the KOSHA Guide (A-24-2019) method. It was carried out twice. Results: As a result of the first measurement, TWA concentration exceeded 4 times the exposure standard and STEL concentration exceeded 16 times, but the inaccuracy and breakthrough of the collection time could not be considered, so the second measurement was conducted. The second measurement result was lower than the first measurement result, but exceeded the exposure standards (TWA, STEL). Conclusions: We were able to confirm that the exposure level of workers in the cleaning process using trichloroethylene exceeded the exposure standard. And it is also considered necessary to grasp the approximate concentration using a detector tube in the preliminary survey.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.05a
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• pp.169-172
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• 2001

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.1
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• pp.55-66
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• 1996

This study was conducted to evaluate breakthrough characteristics of respirator cartridge using multi-organic vapors, including carbon tetrachloride, trichloroethylene, and toluene. The organic vapors were used as single phase, binary system, and ternary system. The results are summarized as follows. 1. Organic vapors studied were 1,000 ppm, 750 ppm, 500 ppm and 250 ppm in single phase. Carbon tetrachloride having the highest molecular weight showed the breakthrough first, and breakthrough sequency by organic vapor was dependent on its molecular weight. The 10% breakthrough times at 1,000 ppm of organic vapor were 97 minutes for carbon tetrachloride, 129 minutes for trichloroethylene and 135 minutes for toluene. 2. When concentrations of organic vapors were at levels of the Threshold Limit Values, the lives of the respirator cartridges were 122 hours in carbon tetrachloride, 18 hours in trichloroethylene and 28 hours in toluene. 3. In the binary system at a total concentration of 1,000 ppm with carbon tetrachloride and trichloroethylene, breakthrough times ranged from 104 minutes to 125 minutes, which were longer than 97 minutes in a single phase (1,000 ppm) for carbon tetrachloride, but shorter than breakthrough times for TCE and Toluene. 4. Breakthrough times in the binary system with carbon tetrachloride and toluene were 131~132 minutes. 5. Breakthrough times in the ternary system with carbon tetrachloride, toluene, and trichloroethyl ene were $120{\pm}8$ minutes, which were longer than 97 minutes in the single phase (1,000 ppm) for carbon tetrachloride, equal to 129 minutes for trichloroethylene, and shorter than 135 minutes for toluene. Those were almost similar to $124{\pm}9$ minutes of breakthrough times in the binary systems.