Risk Assessment of 5-Chloro-2-Methylisothiazol-3(2H)-One/2-Methylisothiazol-3(2H)-One (CMIT/MIT) Used as a Preservative in Cosmetics

Kim, Min Kook,Kim, Kyu-Bong,Lee, Joo Young,Kwack, Seung Jun,Kwon, Yong Chan,Kang, Ji Soo,Kim, Hyung Sik,Lee, Byung-Mu Korean Society of ToxicologyKorea Environmental Mu 2019 Toxicological Research Vol.35 No.2

The mixture of 5-chloro-2-methylisothiazol-3(2H)-one (CMIT) and 2-methylisothiazol-3(2H)-one (MIT), CMIT/MIT, is a preservative in cosmetics. CMIT/MIT is a highly effective preservative; however, it is also a commonly known skin sensitizer. Therefore, in the present study, a risk assessment for safety management of CMIT/MIT was conducted on products containing 0.0015% of CMIT/MIT, which is the maximum MIT level allowed in current products. The no observed adverse effect level (NOAEL) for CMIT/MIT was 2.8 mg/kg bw/day obtained from a two-generation reproductive toxicity test, and the skin sensitization toxicity standard value for CMIT/MIT, or the no expected sensitization induction level (NESIL), was $1.25{\mu}g/cm^2/day$ in humans. According to a calculation of body exposure to cosmetics use, the systemic exposure dosage (SED) was calculated as 0.00423 mg/kg bw/day when leave-on and rinse-off products were considered. Additionally, the consumer exposure level (CEL) amounted to $0.77512{\mu}g/cm^2/day$ for all representative cosmetics and $0.00584{\mu}g/cm^2/day$ for rinse-off products only. As a result, the non-cancer margin of safety (MOS) was calculated as 633, and CMIT/MIT was determined to be safe when all representative cosmetics were evaluated. In addition, the skin sensitization acceptable exposure level (AEL)/CEL was calculated as 0.00538 for all representative cosmetics and 2.14225 for rinse-off products; thus, CMIT/MIT was considered a skin sensitizer when all representative cosmetics were evaluated. Current regulations indicate that CMIT/MIT can only be used at concentrations 0.0015% or less and is prohibited from use in other cosmetics products. According to the results of this risk assessment, the CMIT/MIT regulatory values currently used in cosmetics are evaluated as appropriate.

P278 : Nonablative fractional laser as a tool to facilitate skin penetration of 5-aminolevulinic acid with minimal skin disruption

( In Jung Kang ),( Jeong Hwee Choi ),( Min Jae Gwak ),( Hee Kyeong Lim ),( Mu Hyoung Lee ),( Min Kyung Shin ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Background: Effective penetration of photosensitizer is an essential step in photodynamic therapy (PDT). There have been trials of several methods, including laser treatment, to facilitate prompt and sufficiently deep transdermal drug delivery. Objectives: This study was performed to evaluate the effects of nonablative fractional laser pretreatment on aminolevulinic acid (ALA) penetration of the skin. Methods: Twelve identical treatment areas of 1 × 1 cm2 on the backs of 10 healthy male subjects were mapped. Each area received laser treatment with a different energy and incubation with ALA for different times. Laser treatment was performed with a 1550 nm fractional erbium glass laser, and the laser energy was set to 20 and 50 mJ with a spot density of 50/cm2. ALA incubation time was set to 30, 60, or 180 min. Porphyrin fluorescence was measured. Results: Nonablative fractional laser-pretreated areas showed significantly increased porphyrin fluorescence compared to non-pretreated areas. Laser energy strength and ALA incubation time were positively correlated with ALA absorption. Conclusion: Nonablative fractional laser treatment effectively enhanced ALA skin penetration. Pretreatment with a nonablative fractional laser can be used for ALA-PDT to achieve higher therapeutic efficacy and shortened ALA incubation times with minimal skin barrier disruption compared to ablative laser.

茯笭 人工栽培에 適合한 原木과 種菌 接種量 및 接種方法에 關한 硏究

金成敏,申東一,具漢謨,李武鉉,金善喆 공주대학교산업개발연구소 2000 産業開發硏究 Vol.8 No.-

This study was carried out to improve the culturing method of P. cocos, on saving labor and inoculation amount. Therefore, the result of this experiment was as the following. Proper mycelium growth and density of P. cocos was observed in MCM(mushroom complete medium). In the selection of tree species, pine and larch had better in spawn culture and sclerotia formation condition. In the experiment of pine, Yield was 33.7㎏/3.3㎡. In inoculation amount, conventional method(cross slice inoculation) required 16 ~ 20 bottles/1000cc of spawn. In contrast, short log,drilling inoculation method required 8 ~ 10 bottles/1000cc, 2 ~ 3 bottles/1000cc of spawn, which reduced by 50% and 85 ~ 90% of inoculation respectively. In conventional method, the yield of pine was 23.4㎏/3.3㎡. In the case of drilling and short log inoculation, Yield was 28.7㎏ / 3.3㎡(25㎜ / depth) and 30.1kg / 3.3㎡(35mm / depth), 31.7㎏ / 3.3㎡ respectively, Therefore, short log inoculation was increased by 25% and 35% compared with conventional method. In conclusion, management cost was also saved.

Bi_2Sr_2Ca_(n-1)Cu_nO_y(n=1, 2, 3)의 열기전력 측정연구

김용민,최무용 성균관대학교 기초과학연구소 1989 論文集 Vol.40 No.2

We have measured the thermopower of three phases of Bi_2Sr_2Ca_(n-1)Cu_nO_y for n = 1, 2, 3. The thermopower is found to he larger when n is bigger and its temperature derivative dS/dT is negative irrespective of phases. For n=1, we find that the thermopower itself is negative for all the temperature range above 10K, and when the same sample has been baked in vacuum at 600℃, thermopower vs. temperature curve shows a broad positive peak similar to those seen in rare-earth high-Tc superconductors. Considering these experimental fact, the suggestion that the charge carriers in these materials are holes may be seriously challanged. We have considered a two-band model as an alternative where holes and electrons coexsist as charge carriers.

화상처리를 이용한 디버링 가공물의 품질 측정

송무건,백재용,신관수,유송민 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

In this study a vision system with image processing method have been introduced to find the edge radius of curvature. It was applied to inspect the edge quality of the de burring process product with brush grinding. Size of data was found to be critical in calculating the radius of curvature. Results using laser measurement system were compared.

炭素鋼의 摩擦熔接에서 熔接面의 形狀에 관한 硏究

鞠賢雨,閔宅基,金光日,金茂成 忠南大學校 産業技術硏究所 1994 산업기술연구논문집 Vol.9 No.2

This report deals with a study on figure of friction welding of carbon steel. It is investigated to vary figure. Main result obtained in this study are as follows; 1) In friction welding of carbon steel, the optimization of figure experiments on several type [C(120 )>A(180 )>B(150 )>D(90 )type]. The optimization of figure is C-type(120 ) 2) The tensile strength under 1.0-1.4sec heating time is shown 43.2kgf/㎟, which is the higher than base metal (42kgf/㎟) in C-type. 3) The horizontal hardness is similar to base metal. Heat affected zone where hardness is lower than base metal spreads 3mm far from the friction weld interface in C-type

화상처리를 이용한 연삭공구 인식 및 안면인식 응용

백재용,송무건,유송민 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

An image processing method was applied to characterize a shape of the flexible grinding disk. A disk surface image was taken by CCD camera. Depth of cut was changed to be 2 and 4mm. Circles marked on the disk were captured to extract the key features of the deflection. Notable correlation has been observed between the intervals and the process conditions. Same methodology has been applied to check the symmetry of the human face. Tentative results revealed that symmetry could be checked using the filtered face image.

12Cr 강의 화염경화 표면처리 층의 초음속 물방울 충격에 의한 손상 거동

김광호,이민구,김경호,김흥회,김길무 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.1

Water drop impact erosion properties of the 12Cr steel, currently used as nuclear steam turbine blade material, surface-hardened by the flame hardening process have been characterized. For this, variations of both the maximum erosion depth de,,,,ax and volume loss V with the cumulative impacts n at the supersonic impact velocity (~350 m/s) have been investigated for the as-received and flame-hardened 12Cr steels with different hardnesses. Typically all the samples showed an erosion-time characteristic involving the incubation period initially followed by the steady state period. It is also found that the d_(e,max) increases stepwise-like with the number of impacts n, which results from a sudden formation of craters by crack propagation. Compared to those for the as-received 12Cr steel, the flame-hardened ones showed an excellent resistance to water drop impact erosion with 2.2~2.8 times higher incubation time n, and 115~1/8 times lower erosion rate a. In the incubation period the as-received 12Cr steel was damaged by ductile depression and ploughing, while the flame-hardened 12Cr steel by fatigue cracks and brittle platelet deformation. Erosion in the steady state period was developed by the cleavage fracture commonly. (Received July 22, 2004)

산소 결핍도 변화에 따른 YBa_2 Cu_3 O_7-y의 열기전력 변화

강원남,김용민,조경철,최무용 성균관대학교 기초과학연구소 1988 論文集 Vol.39 No.1

To clarify the superconducting mechanism of the high Tc oxide superconductors, we have studied the interactions among electrons and elementary excitations and the electronic energy band structure by measuring the thermoelectric power of YBa_2 Cu_3O_7-y with various oxygen deficiencies. We have found that the major charge carriers in YBa_2Cu_3O_7-y are holes, that the width of the electronic energy band is larger than the intial estimation, and that the interaction between electrons and phnonos in the material is not strong enough to explain the high Tc super conductivity, while we have seen an evidence that there exist strong interactions between electrons and magnetic excitations.

플라이애시를 다량 사용한 콘크리트의 수화발열 특성과 압축강도 특성에 관한 실험적 연구

조규현,박무영,백민수,김우재,임남기,정상진 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

This study is for the great quantity use of fly-ash. For the producing of high volume concrete from the use of fly-ash, the method of replacement between bonding agents and fine aggregate by fly-ash at the slt was used that the adiabatic temperature rise of concrete about the mass member which bad been produced by the method that was mentioned before, and the hydration heat of the core test pieces in concrete was measured. Also the core test pieces which were replaced with fly-ash was studied by the compressive strength's comparison between standard care test pieces and core test pieces. In the case of mass test pieces, hydration heat and the time to reach the highest temperature were decreased by an increase in replaced fly-ash's amounts of concrete. In addition, among the test pieces having the same amounts of concrete, the test pieces having more replaced amounts of fly-ash's fine aggregate showed higher hydration heat and the increased time to reach the highest temperature. Compressive strength was also increased by hydration heat's decrease according to fly-ash replacement. Replacement of fly-ash was more effective in high temperature environment.