• Environmental Mutagens and Carcinogens
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• v.21 no.1
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• pp.57-62
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• 2001

Bacterial reverse mutation assays were performed for 20 workplace chemicals in Korea, which were selected among workplace chemicals under the Korea Industrial Safety and Health Act (KISHA) with the occupational exposure levels (OELs). The assays were carried out by using the pre-incubation method ($37 ^{\circ}C$, 20 min) with and without metabolic activation using Salmonella typhimurium TA98, TA100, TA1535, TA1537 and E. coli WP2uvrA. The chemicals were tested at 5 concentrations both in the preliminary and the second assays. Despite the cell toxicities, there were no chemical-induced mutagenicities with or without metabolic activation in any of 20 chemicals.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.20-25
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• 2012

Objectives: Hazard identification is the most important step in occupational health monitoring at the workplace. This paper reviewed the several related stuffs to the hazard identification in the semiconductor industry. Methods: I checked the MSDS system, chemical toxic informations, trade secrets and by-products by experience and the literature used in semiconductor industry. Results: I found and experienced as follows; (1) There are a few inventory and history of chemicals used in workplace. Toxic information of chemicals to be available is very limited. (2) There are many trade secrets in MSDS for chemical mixtures. It is difficult to identify the accurate information from MSDS. (3) By-products is necessary to identify that they will produce in workplace. Conclusions: It is necessary to regulate the obligations of employers which check the inventory and history of chemicals used in workplace. It is necessary to amend the trade secrets in MSDS system.

• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.419-429
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• 2016

Objectives: According to the new Chemical Control Act from the Korean Ministry of Environment (2014-259), workers handling hazardous chemicals should wear personal protective equipment (PPE). However the act simply states in basic phrases that every worker handling one or more of the 69 listed chemicals should wear PPE and does not consider the unique hazard characteristics of chemicals and work types. The main purpose of this study is to provide basic data to revise the act to suit particular work processes and situations. Methods: The hazard rank of the substances was classified based on hazardous characteristics such as LC50 and vapor pressure using matrix analysis. The workplace exposure risk of the substances was also determined through a matrix analysis based on the previously determined hazard ranks and the demands of manual handling together with the likelihood of accident frequency of the operation combined with the exposure of workers during spill accidents. Results: To meet the demands for developing subsequent guidelines for the risk-based application of PPE in hazardous workplaces, this study sorted the 69 listed chemicals into five hazardous categories based on their LC50 and vapor pressures, and also assigned exposure categories according to exposure vulnerability for various types of work which are frequently performed throughout the life cycle of the chemicals. Conclusion: In the next study, an exposure risk matrix will be produced using the hazard rank of chemicals and workplace exposure risk, and then PPE will be selected to suit the categories of the exposure risk matrix.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.2
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• pp.102-112
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• 2009

The greatest concern of vapor/gas respirators is when to exchange chemical cartridges, but it is very difficult to estimate the breakthrough time of them in the workplace spot due to so many factors influencing on breakthrough. There needs to study on estimating cartridge exchange period available practically in the spot, even if it is not precise. In the previous study, authors suggested the method on estimating service-life of chemical cartridges using cartridges discarded after use. This followed study was to estimate exchange period for chemical cartridges using comparison of concentrations between Korean Occupational Exposure Limits (KOELs) and odor thresholds of chemicals. Chemicals were divided into four groups, I, II, III and IV groups. Group I chemicals are relatively safe if cartridges are just or slightly delayed exchanged when smelling since odor thresholds were less than 0.5 times KOELs. Odor threshold of Group II chemicals are 0.5~2.0 times KOELs and potentially hazardous if cartridges are exchanged when smelling. Those chemicals should be conducted program on estimating service-life of cartridges, which was just previously published (J Kor Soc Occup Environ Hyg 2008;18(3) 204-215). Group III chemicals (odor thresholds are more than 2.0 times KOELs) and Group IV chemicals (odorless or no data for smelling) must be performed the above mentioned program before cartridges. Even if this method on cartridge exchange using odor threshold is practically widely used in the workplace spot in the present, program on estimating service-life of cartridges is recommended for all chemicals to reduce potentially hazards.

• Journal of Environmental Health Sciences
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• v.27 no.4
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• pp.85-91
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• 2001

The regulation of Material safety data sheets(MSDS) was required for the chemicals in use in the workplace from July 1976. Under the provisions of the workplace hazardous materials information system, employers in Korea must be provided with accurate and comprehensive MSDS. To examine the reliability of MSDS for organic solvents, 63 organic solvents and MSDS were collected from the workplace of 39 companies located in Kyonggi province. Manufacture\`s MSDS were compared with the actual composition of the collected samples, and further examined the reliability by checking whether the chemicals analyzed were included in the MSDS correctly. 38 solvents were able to analyze their composition by gas chromatography-mass selective detector(GC-MSD). Among them, 28 solvents were incorrect in their composition and contents. In some case, health hazardous or carcinogenic chemicals which were not included in the MSDS were detected from samples. As a result of evaluating whether the MSDS correspond to the regulation required by Industrial Safety and Health Act (ISHA), the information in the MSDS including hazard classification, occupational exposure level, toxicity, regulatory information were incorrectly provided, and some MSDS did not disclose carcinogenic in their MSDS, and some MSDS were not written in the standard format. From this survey, continuous monitoring and promoting correct MSDS, and analyzing the components of the solvents were required to endure the reliability of MSDS for organic solvents.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.32-41
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• 2012

Objectives: Information of chemical in electronics industry has not been known enough, although workers' health hazards by chemicals in this industry have been regarded serious. The who always contribute to reveal and control the health hazards and risks in electronics industry have not been the industry but the occupational or environmental victims and grassroot organizations. The similar phenomena can be observed in Korea. Methods: The experiences of individual workers on the occuapational safety and health in semiconductor factory were heard separately and integrated with related literatures. Results:: The first part of this article is largely based on the memories and experiences of individual workers of semiconductor factories, mainly from S semiconductor. Common features of those experiences can be a good resource for detail understanding of the workplace, especially under the situation without any transparent disclosure of information by the governments or the companies. The second part of this article deals with several factors to be considered for control of exposure in workplace; characteristics of workplace and workforce, types of chemicals used, and the way of using the chemicals. Then the current social issues on work-relatedness of cancers of S semiconductor workers are presented briefly. Conclusions: As a conclusion, current OSH situations and issues in Korean electronics industry raise the need of changes in OSH culture. General adaptation of precautionary principle, internalization of costs, and extended responsibility of producers are needed urgently. The OSH professionals both in public and private sectors should support these agendas under their social obligation to protect workers' health.

• 대한예방의학회:학술대회논문집
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• 1994.02a
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• pp.431-438
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• 1994

As currently conducted, standard rodent bioassays do not provide sufficient information to assess carcinogenic risk to humans at doses thousands of times below the maximum tolerated dose. Recent analyses indicate that measures of carcinogenic potency from these tests are restricted to a narrow range about the maximum tolerated dose and that information on shape of the dose-response is limited in experiments with only two doses and a control. Extrapolation from high to low doses should be based on an understanding of the mechanisms of carcinogenesis. We have postulated that administration of the maximum tolerated dose can increase mitogenesis which, in turn. increases rates of mutagenesis and, thus, carcinogenesis. The animal data are consistent with this mechanism, because about half of all chemicals tested are indeed rodent carcinogens, and about 40% of the positives are not detectably mutagenic. Thus, at low doses where cell killing does not occur, the hazards to humans of rodent carcinogens may be much lower than commonly assumed. In contrast, for high-dose exposures in the workplace, assessment of hazard requires comparatively little extrapolation. Nevertheless. permitted workplace exposures are sometimes close to the tumorigenic dose-rate in animal tests. Regulatory policy to prevent human cancer has primarily addressed synthetic chemicals, yet similar proportions of natural chemicals and synthetic chemicals test positive in rodent studies as expected from an understanding of toxicological defenses, and the vast proportion of human exposures are to natural chemicals. Thus, human exposures to rodent carcinogens are common. The natural chemicals are the control to evaluate regulatory strategies, and the possible hazards from synthetic chemicals should be compared to the possible hazards from natural chemicals. Qualitative extrapolation of the carcinogenic response between species has been investigated by comparing two closely related species: rats and mice. Overall predictive values provide moderate confidence in interspecies extrapolation; however, knowing that a chemical is positive at any site in one species gives only about a 50% chance that it will be positive at the same site in the other species.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.1
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• pp.27-34
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• 2013

Objectives: The purpose of this study is to calculate the worker-DNEL (Derived No Effect Level) values using the REACH guidance and compare the calculated DNELs with existing Korea occupational exposure limits (KOELs) for evaluation of the applicability of the worker-DNELs as provisional occupational exposure limits for chemicals that are not established KOELs in the workplace. Methods: The worker-DNELs for 46 chemicals among 113 hazardous substance requiring management were calculated using the REACH guidance, and a paired t-test was performed to see if there is any statistical difference between two lists (worker-DNELs vs KOELs). The ratios of KOELs over worker-DNELs were also calculated to compare the overall levels of two lists using the geometric means method. Results: The calculated worker-DNELs for 46 chemicals ranged from 0.001 to $329mg/m^3$ (GM= 6.9, GSD = 10.8), and appeared to be a significant difference between the worker-DNELs and the KOELs (p < 0.01). In addition, the ratios of KOELs over worker-DNELs ranged from 0.3 to 394 times (GM = 10.2, GSD = 3.9), indicating that the worker-DNELs were, on average, 27 times lower than the KOELs. Conclusions: Therefore, the study results show that the calculated worker-DNELs can be applied and used as provisional occupational exposure limits in the workplace in order to reduce worker exposures to chemicals and health risks, and manage potential worker exposures based on the precautionary principle through comprehensive chemical risk assessment.

• Journal of Technologic Dentistry
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• v.32 no.3
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• pp.221-232
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• 2010

Purpose: It is necessary for dental technicians exposed to hazardous chemicals in the dental laboratories to be informed of the various harmful effects of chemicals for their health and safety. The purposes of this study was to investigate the actual condition of the use of MSDS in dental laboratories and the recognition rate of MSDS for dental technicians. Methods: 231 dental technicians who were self-written questionnaire. The results were analyzed by SPSS 12.0. The answers to the questionnaire underwent frequency analysis, chi-square test and correlation analysis were performed to investigate association between health effects and recognition rate of chemical information. Results: The results from the effects of damage caused by chemicals 60.7%, and when it was less than 2 years working experience 47.6%. Currently any dental laboratories(rooms) was not furnished MSDS(0%) and even similar data furnishing rate was only 17.3%. Answer rate of 'Do not know about MSDS' was 73.6%. In addition to, education in the types and characteristics of chemicals(74.5%) does not receive all the higher education. For the question of 'To prevent human risks and accidents, is to provide chemical information needed', the answer rate of 'needed' was 87.2%. Moreover, the answer rate of 'To provide chemical information that could prevent accidents' was 76.6%. Therefore it was found that dental technicians need to be provided for chemical information. In addition, they wanted to get education related to chemicals used in the workplace(80.5%), and 90.9% was answered that they was willing to keep MSDS in they workplace. Conclusion: This study investigated the current dental laboratories(rooms) and the MSDS for the awareness and recognition of workers was very low, education was not being conducted properly. The dental laboratories(rooms) of the compact characteristics of the MSDS was not reasonably accessible and the furnishing location, dental laboratories(rooms) for the real item was needed for improvement. MSDS for dental technicians through education and promotion of information about chemicals and chemicals was to prevent health problems caused by the MSDS that will raise awareness of the necessity.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.191-199
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• 2012

Objectives: The study aim was to evaluate the application of a chemical exposure assessment tool for the Korean workplace. The Ministry of Employment and Labor in Korea (KMOEL) introduced the need for workplace risk assessments in 2011, requiring the Korean chemical industry to consider both domestic and international chemical regulation policies (e.g., estimations of exposure scenarios). Exposure scenarios are required in the European Union as part of material safety data sheets (MSDS) under the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) system. Methods: Although many programs for the estimation of exposure have been developed worldwide, to date there is no standard for the Korean workplace. To develop programs suitable for the Korean workplace, we examined the applicability of the European Center for Ecotoxicology and Toxicology of Chemicals target risk assessment (ECETOC TRA), which is recommended by the European Chemical Agency (ECHA). Results: To investigate the applicability of the ECETOC TRA to Korean industry, this study simulated 15 industrial processes. The predicted respiratory exposures for four processes using origin input parameters were underestimated compared to the measured respiratory exposure. Using calibrated input parameters, results for two processes were underestimated compared to the measured respiratory exposure. This result suggests that the use of calibrated input parameters reduces the differences between predicted and measured respiratory exposure. Conclusions: we developed applicable exposure estimating method by modifying the ECETOC TRA program; one suggested the development of exposure estimating program that explains Korea domestic workplace exposure scenario.This study will support the introduction of exposure scenario in MSDS system and protect health of worker from hazardous chemical.