• Journal of Environmental Health Sciences
• /
• v.35 no.3
• /
• pp.235-238
• /
• 2009

In Korea, talc that has been widely used for a lot of consumer products as well as industrial usage until recently was found to be contaminated with asbestos. It becomes a major social issue. Critical health risk about both talc and talc contaminated with asbestos was summarized through literature review. It has been confirmed that talc can pose ovarian cancer when talc powder is used in the genital area. International Agency for Research on Cancer (IARC) already concluded that the perineal use of cosmetic talc can cause possibly carcinogenic to humane(Group 2B), although there was study reporting the lack of a consistent an established correlation between perineal dusting frequency and ovarian tissue talc concentrations and the lack of a consistent dose-response relationship with ovarian cancer risk. The association between talc exposure and ovarian cancer is as strong as in recent studies. The epidemiological studies to date provided inadequate evidence for the carcinogenicity of either inhaled or ingested talc that does not contain asbestos or asbestosiform fibers. Future studies should focus on seeking evidence in talc-exposed populations, collecting reliable information on age at initial used of body powder, exposure assessments related to talc use and dose response relationship in order to identify possible risk of talc ingested or inhaled.

• Journal of the Korean Ceramic Society
• /
• v.34 no.12
• /
• pp.1213-1220
• /
• 1997

Effect of particle size of alumina and amount of talc on tape casting and densification behaviors of alumina-talc system were investigated. The pseudoplastic behaviors of slurries increased with increase in amount of talc addition and decrease in alumina particle size. In case of using coarse alumina powder, densification of specimens were accelerated with increase of sintering temperature and amount of talc addition. On the contrary, fine alumina powder retarded of rearrangement of alumina particle during liquid phase sintering due to premature densification of alumina matrix region before formation of liquid phase and then densification of specimens were suppressed with increase of sintering temperature and amount of talc addition.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.47 no.1
• /
• pp.31-40
• /
• 2021

The main stability factors of the pressed powder include hardness and drop stability. In general, for pressed powder with talc, the hardness and drop stability are evenly met and the skin texture is excellent. Recently, more than ever customers are looking for a replacement due to asbestos issue of talc. Therefore, it is urgent to develop a pressed powder formulation without talc that maintains stability and does not lose its sense of use. In this study, experiments were conducted to find the optimal ingredients mixing ratio to make talc-free pressed powder. The characteristics of raw materials used mainly in powder were checked and the ratio was changed, and the lightness and hardness were measured and drop test was conducted. If the natural mica ratio was higher than the synthetic mica or non-coated silica was used instead of the coated silica, the hardness and drop stability were lower than the content containing talc, but the lightness was similar. Conversely, if the synthetic mica ratio was equal to or higher than the natural mica ratio and the coated silica ratio was equal to or higher than the non-coated silica ratio, the hardness and drop stability of the content containing talc were similar, but the lightness was low. It was found that the hardness was higher than the content containing talc, but the drop stability was lower. Therefore, further study of the correlation between hardness and fall stability is also thought to be necessary.

• Journal of the Korean Ceramic Society
• /
• v.35 no.12
• /
• pp.1308-1315
• /
• 1998

Effects of particle size of alumina on densification behavior during liquid-phase sintering of alumina-talc system were investigated with emphasis on particle rearrangement process. In the case of using coarse alu-mina powder densiication of specimens was rapidly accelerated after formation of liquid phase due to easy particle rearrangement process with addition of talc and increase of sintering temperature. On the contrary when fine alumina powder was used premature densification of alumina matrix region formed before for-mation of liquid phase rigid skeleton structure and then it seemed to inhibit rearrangement process during crease of sintering temperature. As results the densification of specimens using coarse alumina powder was higher than that of the case of using fine one.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.31 no.4
• /
• pp.295-303
• /
• 2021

Objective: Paint manufacturing industry workers are exposed to various lung cancer carcinogenic substances including hexavalent chromium and crystalline silica. Studies have been conducted on lung cancer in Paint manufacturing industry workers and the concentration of hexavalent chromium in paint industry; however, the concentration of crystalline silica and hexavalent chromium and cases of lung cancer in a single Paint factory has never been reported in Korea. Methods: To determine whether the cancer was related to his work environment, we assessed the level of exposure to carcinogens during pouring and mixing talc and pigment. In addition, a mask fit test was performed for the worker. Results: Analysis of talc and silica bulk powder materials showed that crystalline silica (quartz) was 5% in talc and 100% in silica. The green and yellow pigments contained 87% and 92% of lead chromate, respectively. Our quantitative analysis of pigment powder samples showed that the hexavalent chromium contents quantified in the green and yellow pigment samples were 87% and 92%, respectively. In order to estimate his exposure level of hexavalent chromium, we measured a personal exposure level of hexavalent chromium for a worker in accordance with the National Institute for Occupational Safety and Health #7605 method. The results showed that the worker was exposed to the high level of hexavalent chromium (0.033 mg m-3). In addition, the talc powder also contained 5% quartz, and the worker's exposure level to respirable quartz exceeded OEL. As a result of the respiratory protection fit test for workers, the overall Fit Factor was '15' when wearing a second-grade mask and '25' when wearing a first-grade mask, significantly lower than the US Occupational Safety and Health Agency (OSHA) pass value of "100". Conclusion: Workers who pouring and mixing powder materials such as talc or colored pigments in paint manufacturing company may be exposed to high concentrations of carcinogenic substances. These findings indicate that it is necessary to local ventilation system inspection, safety and health education for employers and workers, and periodically monitoring and manage the working environment.

• Journal of Chest Surgery
• /
• v.37 no.2
• /
• pp.166-172
• /
• 2004

When compare with blebectomy or bullaectomy simply and pleurodesis together in treatment of primary spontaneous pnevmthorax, the later has been realized as the method that can reduce the recurrent rate after surgical operation. Therefore, in this study, we compared the merits and demerits of the clinical result of chemical pleurodesis that use Talcum powder in pleurodesis and mechanical pleurodesis that use apical pleurectomy and analyzed the reappearance rate etc. Material and Method: The Pleurodesis through the apical pleurectomy and talc powder insufflation had been used as secondary procedure after blebectomy of spontaneous pneumothorax from January 1, 2000 to June 30, 2002. This study consisted of a retrospective review of 68 patients who were treated with apical pleurectomy, and 84 patients treated with talc powder insufflation. We compaired the apical pleurectomy and talc powder insufflation in terms of age, sex, cause of operation, number of used autosuture staple, tine duration of procedure after blebectomy, severity of pain and complication after operation, postoperative air leakage period, duration of chest tube insertion, hospitalization, and recurrence rate of pneumothorax. Result: Time required for secondary procedure was longer in apical pleurectomy than talc powder insufflation. Postoperative pain was more severe in talc powder insufflation than apical pleurectomy. Otherwise there was no significant difference between two methods. Conclusion: Although Talc powder insufflation is more convenient than apical pleurectomy, the difference is not large and, the severity of postoperative pain is worse in talc powder insufflation. Therefore apical pleurectomy can be recommended for the secondary surgical procedure after blebectomy of primary spontaneous pneumothorax can be recommended.

• Journal of the Korea Institute of Building Construction
• /
• v.6 no.4 s.22
• /
• pp.93-98
• /
• 2006

Admixture materials are used in mixing concrete or mortar to improve quality and performance of the concrete. This study examines the potential use of talc as a substitute for cement, the benefits of recycling waste resources for economical efficiency and quality improvement of concrete. The test was carried out by replacing the plain mix with fine grains of talc at the rate of 10%, 20%, and 30%. Talc was divided into three groups depending on the degree of pulverizing. For wet concrete, porosity, slump, bleeding per unit, and setting time by penetration resistance were measured; similarly, for dry concrete, strength and watertight Property were tested. Test results showed that the amount of bleeding and setting time could be shortened, but the strength and watertight proofing severely deteriorated. However, at the replacement rate of 10%, talc showed equal performance with the plain at all degrees of pulverization, which suggests its potential use as admixture material.

• Transactions of the Korean hydrogen and new energy society
• /
• v.17 no.1
• /
• pp.109-116
• /
• 2006

The heat treatment characteristics of natural talc sample was investigated in diverse analytical view point. The mass decrease comes to heat treatment was resulted by the continuous and the discontinuous process and the obtained result show very similar two step profiles with 8.9 % mass decrease. The dehydroxylation of -OH groups contained talc crystal was analyzed by spectroscopic method and the crystallographic variations was also observed after heat treatment. According to XPS result, the magnesium hydroxide($Mg(OH)_2$) of untreated talc powder changed to magnesium oxides(MgO) after heat treatment.

• Journal of the Mineralogical Society of Korea
• /
• v.12 no.1
• /
• pp.1-10
• /
• 1999

Talc (Mg3Si4O10(OH)2), one of the sheet silicate minerals, which is the hydrothermal alteration product of serpentinite at Cheongarm mine was prepared for the high pressure compressibility studies. Energy dispersive X-ray diffraction experiment was carried out using the Synchrotron Radiation with the Mao-Bell type diamond anvil cell at room temperature. Polycrystalline talc was mixed with MgO powder for pressure sensor as well as pressure medium in the sample chamber. High pressure runs were performed at pressures up to 35.2 GPa. Talc shows no phase transition within the present high pressure region. Bulk modulus of this talc was determined by the Birch-Murnaghan equation of state to be 78 GPa assuming its first pressure derivative Ko' of 4.

• Journal of the Korean Applied Science and Technology
• /
• v.16 no.3
• /
• pp.241-247
• /
• 1999

In this study, the relation of the preservation efficacy reduction with methyl paraben of parahydroxybenzoic acid derivatives was investigated using the dialysis membrane method with tween-80 of surfactant and $TiO_2/Talc$ of inorganic powder meterial from emulsion system. It was found that the preservation efficacy of tween-80 and $TiO_2/Talc$ from emulsion system was reduced due to the adsorption of methyl paraben. According to the microbe test, In case of tween-80, MBC appeared in 0.19 w/v% and in case of $TiO_2/Talc$, MBC appeared in 0.22w/v% / 0.23w/v%. In general, the equation of Talc's adsorption weight($A{\cdot}W$) has a tendency to show in $A{\cdot}W=11.5C^{0.745}$