• Toxicological Research
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• v.11 no.1
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• pp.117-125
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• 1995

In order to examine the mechanism of asbestos clastogenicity, CHO cells were treated with chrysotile and crocidolite. Crocidolite and chrysotile were able to induce lipid peroxidation in a dose dependent manner. Ultrafiltrate of culture media from CHO cells treated with chrysotile/crocidolite induced sister chromatid exchange in CHO cells. Ultrafiltrate of culture media from CHO cells treated with chrysotile induced chromosome aberration but it was not statistically significant. Simultaneous treatment of 3-Aminobenzamide (3-AB) or cytosine arabinoside (Ara C) with crocidolite had no effect on the frequency of chromosome aberration by crocidolite whetease posttreatment of caffeine significantly increased the chromosomel aberration by crocidolite. This indicated that DNA damage by asbestos took place at late stage of cell cycle. The results suggested that the ultrafiltrate of media contained clastogenic factor (CF) and lipid peroxidation might be involved in the formation of CF.

• Journal of Environmental Health Sciences
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• v.37 no.1
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• pp.57-63
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• 2011

Crocidolite quality control (QC) sampling created by the wet generation method has been validated by validation tests such as the accuracy, precision, and storage tests. For this study we designed and developed a manufacturing apparatus and standard operating procedure for making these QC samples. The most important step in the procedure of making QC samples was the stage eliminating static electricity in asbestos fibers. This static electricity hampers the fibers clog functioning. In accuracy and precision tests by phase contrast microscopy analysis, the difference between the reference values and the studied values was at maximum 17.8%. This satisfies the AIHA proficiency analytical test criteria for asbestos. We could confirm the nearly even distribution of crocidolite fibers on the membrane filter. Also, there was no loss of fibers in the storage test after the one month.

• 대한예방의학회:학술대회논문집
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• 1996.10a
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• pp.195-196
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• 1996

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.6
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• pp.703-712
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• 1999

In order to determine the number concentration of asbestos, it is initially necessary to develop a method to identify the type of asbestos. Thus a SEM/EDX was used to obtain both physical and chemical information from known asbestos samples as reference samples. Based on these information, we could make a source profile matrix consisted of a glass fiber and 3 other types of asbestos such as chrysotile, crocidolite, and tremolite. After collinearity test was performed for these sources, we could successfully develop an expert system by C-language to separate and to identify various unknown types of fiber particles. The expert system was perfectly self-verified with original reference data. Then the program was extensively applied to survey indoor and outdoor environment such as a residential area, an elementary school, and underground store, and an auto junkyard. As a result for surveying, a total of 442 individual fibrous particles were well classified into 4 types of particle classes above mentioned; 5.4% of chrysotile, 4.1% of crocidolite, 3.6% of glass fiber, and 86.9% of unknown fibers in terms of number concentration. However, tremolite was not detected in the study sites. All the samples were satisfied with the recommendation level of 0.01 f/cc.

• Toxicological Research
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• v.17 no.3
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• pp.163-165
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• 2001

A patient,58 years of age, with suspected 0/l pneumoconiosis since 1993, complained of a dry cough and exertioning dyspnea for 6 months. He had worked in an asbestos company for more than 20 years from 1974. He was subsequently diagnosed with an interstitial lung disease during an annual special health check-up for asbestos workers. h chest X-ray showed an interstitial lung disease and high-resolution computed tomography (HRCT) showed a round opaque asbestosis with chronic hypersensitivity pneumonitis. A pulmonary function test indicated that the patient had a mild restrictive lung disease with FEV1 1.67 litters and 82% FEVl/FVC. The bronchoalveloar larvage fluid included many asbestos bodies, indicating previous exposure to asbestos. Transmission electron microscopy (TEM) using an energy dispersive X-ray analyzer (EDX) revealed many asbestos bodies consisting of mainly crocidolite fibers (6,071$\times$$10^6$fibers/g of dry lung). The patient had an unusually high asbestos content of 6,112$\times$$10^6$ asbestos fibers/9 of dry lung.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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• pp.102-110
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• 2001

To establish an accurate asbestos analysis method for workplace samples, chrysotile, amosite, crocidolite, tremolite, actinolite, and anthophyllite asbestos fibers were analyzed for their morphology, atomic content and electron diffraction patterns. The morphology of asbestos fiber was evaluated in $10,000{\times}$ magnification. The atomic contents was analyzed by X-ray analyzer (TEM-EDX). Asbestos fibers were further assessed using electron diffraction (ED) patterns to provide an additional criterion for classifying the asbestos fibers. Twenty asbestos fibers were initially randomly selected for morphological evaluation; based on an aspect ratio (length : diameter = 3:1). Then the fibers were determined for their EDX spectrums and ED patterns. Our results showed that only chrysotile fiber has a hollow tube structure to be distinguished from other asbestos fibers. Although asbestos fibers had similar morphology, they had different EDX spectrums and ED patterns. Our results on the atomic content of asbestos fibers were very similar to those of other researchers, but amosite and crocidolite had a little difference in atomic content compared with the results from other researchers. The difference may be due to the difference in equipment or asbestos sample selection. A study on asbestos samples from biological specimens to establish a criterion for determining occupational asbestos exposed diseases should be done in the near future.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.254-263
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• 1998

A worker employed in a serpentine mine was found developed mesothelioma as the first case of Korea in 1997. Asbestos was known as a causative agent for mesothelioma. Thus, asbestos contamination in mines could be a big health threat to those workers who were unknowingly exposed. However, there was no report that any minerals found in Korea contained asbestos. This study was carried out to find the presence of any asbestiform fibers in minerals which could be obtained in Korean mines. We examined fifteen minerals from 44 mines which were suspected contaminated with asbestiform fibers. Asbestiform analysis was done with high resolution transmission electron microscope(TEM), with energy dispersive X-ray spectroscope(EDX) and X-ray diffraction(XRD) analyses. Among asbestiform fibers, chrysotile was found in chrysotile, serpentine, talc and pyrophylite specimens from 11 mines. Tremolite was found in tremolite and talc specimens from three mines. Mordenite was found in zeolite specimens from two mines. Wallastonite and sepiolite were found in wallastonite and sepiolite specimens respectively. Crocidolite, antigorite and actinolite were found from talc specimens. But no asbestiform fiber contaminants were found in doromite, vermiculite, limestone, marble, gypsum, kaolin, and clary specimens. Thus, these asbestiform fibers such as such as chrysotile, tremolite, mordenite, crocidolite, antigorite and actinolite could be the responsible agents for the health hazards such as mesothelioma and other cancers.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1999.05a
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• pp.73-73
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• 1999

• Journal of environmental and Sanitary engineering
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• v.18 no.1
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• pp.8-14
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• 2003

Asbestos is composed of long thin fibers approximately diameter $0.02\mu\textrm{m}$ and flexibility, strength, electrical, thermal conditions. The most common asbestos are : Chrysotile(white), Crocidolite(Blue), Amosite(Brown). Asbestos was first introduced in the Korea in 1960 and installation of these products continue through the late 1970's and even the early 1980's. Bu-pyung basement stores in Korea were surveyed from September 25 to October 26, 2001. The purpose of this research was to evaluate worker-exposure to asbestos, comparing to the standards and to research notice of inhabitants about asbestos. Fifteen personal samples and six areas were collected using Gillian Air Sampler. Result of this research were as follows. 1. The most of asbestos exposure concentrations keeps to the criterion(OSHA(Occupational Safety and Health Adminisoation), NIOSH) but forty three percent of the Six samples exceeded the EPA (Environmental protection Agency) of 0.01 fibers/cc. 2. All of places compliced to the standards but there is no "Safe level" of asbestos exposure to the people. Especially people who are expose more frequently over a long time are more at risk.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.146-151
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• 2014

Objectives: Chrysotile is mineralogically distinct from amphiboles, displaying a notably different chemical structure. The thin sheets that form chrysotile fiber lead to the ability of the lung/macrophage system to decompose the chrysotile fibers. This study was performed in order to compare the physicochemical characteristics of Korean asbestos with those of Canadian amphiboles. Materials: An acid solubility test for each test substance was done to compare pH 4.5 and pH 1.2 distilled water. Asbestos fibers which had been placed in acid solutions for five days, five weeks and weeks were analyzed with a transmission electron microscope equipped with an energy dispersive X-ray spectrometer (TEM-EDS). Results: The composition element (Mg) of Korean chrysotile, Korean anthophyllite and Canadian amosite significantly decreased from 5 days and also decreased significantly after 5 weeks and 10 weeks. Only the composition (Mg) of Canadian crocidolite did not change under any conditions. From 5 days, the Mg of Korean chrysotile, Korean anthophyllite and Canadian amosite were significantly lower than before the acid treatment, but there were no changes over time or by the pH of the acid solutions. Particularly after 10 weeks, the composition (Mg) of Korean chrysotile in the pH 1.2 acid solution showed a rapid reduction of 15.86%. Conclusions: Korean chrysotile was very weak in an acid environment, beginning to show significant changes after 5 days. The Mg component rapidly decreased after 10 weeks in the pH 1.2 acid solution.