http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
다매체 노출을 고려한 Perchloroethylene의 인체위해성평가연구
서정관,김탁수,조아름,김필제,최경희,Seo, Jungkwan,Kim, Taksoo,Jo, Areum,Kim, Pilje,Choi, Kyunghee 한국환경보건학회 2014 한국환경보건학회지 Vol.40 No.5
Objectives: Perchloroethylene (PCE) is a volatile chemical widely used as a solvent in the dry-cleaning and textile processing industries. It was evaluated as Group 2 "probably carcinogenic to humans" by the Integrated Risk Information System (IRIS) of the United State Environmental Protection Agency (U.S. EPA) in 2012. In order to provide a scientific basis for establishing risk management measures for chemicals on the national priority substances list, aggregate risk assessment was conducted for PCE, included in the top-10 substances. Methods: We conducted the investigation and monitoring of PCE exposure (e.g., exposure scenario, detection levels, and exposure factors, etc.) and assessed its multi-media (e.g., outdoor air, indoor air, and ground water) exposure risk with a deterministic and probabilistic approach. Results: In human risk assessment (HRA), the level of human exposure was higher in the younger age group. The exposure level through inhalation at home was the highest among the exposure routes. Outdoor air or uptake of drinking water represented less than 1% of total contributions to PCE exposure. These findings suggested that the level of risk was negligible since the Hazard Index (HI) induced by HRA was below one among all age groups, with a maximum HI value of 0.17 when reasonable maximum exposure was applied. Conclusion: In conclusion, it was suggested that despite low exposure risk, further studies are needed considering main sources, including occupational exposure.
조아름,김탁수,서정관,윤효정,김필제,최경희,Jo, Areum,Kim, Taksoo,Seo, JungKwan,Yoon, Hyojung,Kim, Pilje,Choi, Kyunghee 한국환경보건학회 2015 한국환경보건학회지 Vol.41 No.6
Objectives: Risk assessment is a tool for predicting and reducing uncertainty related to the effects of future activities. Probability approaches are the main elements in risk assessment, but confusion about the interpretation and use of assessment factors often undermines the message of the analyses. The aim of this study is to provide a guideline for systematic reduction plans regarding uncertainty in risk assessment. Methods: Articles and reports were collected online using the key words "uncertainty analysis" on risk assessment. Uncertainty analysis was conducted based on reports focusing on procedures for analysis methods by the World Health Organization (WHO) and U.S. Environmental Protection Agency (USEPA). In addition, case studies were performed in order to verify suggested methods qualitatively and quantitatively with exposure data, including measured data on toluene and styrene in residential spaces and multi-use facilities. Results: Based on an analysis of the data on uncertainty, three major factors including scenario, model, and parameters were identified as the main sources of uncertainty, and tiered approaches were determined. In the case study, the risk of toluene and styrene was evaluated and the most influential factors were also determined. Five reduction plans were presented: providing standard guidelines, using reliable exposure factors, possessing quality controls for analysis and scientific expertise, and introducing a peer review system. Conclusion: In this study, we established a method for reducing uncertainty by taking into account the major factors. Also, we showed a method for uncertainty analysis with tiered approaches. However, uncertainties are difficult to define because they are generated by many factors. Therefore, further studies are needed for the development of technical guidelines based on the representative scenario, model, and parameters developed in this study.
SWCNT 및 MWCNT의 기관내 점적주입 후 폐 계면활성제의 분석
이병우(Byeongwoo Lee),서정관(Jungkwan Seo),심일섭(Ilseob Shim),엄익춘(Igchun Eom),김필제(Plije Kim) 한국환경보건학회 2017 한국환경보건학회지 Vol.43 No.4
Objectives: Carbon nanotubes (CNTs) are next-generation industrial nanoparticles which possess excellent mechanical strength along with good thermal conductivity and electric properties. Given these characteristics, carbon nanotubes are being widely applied in various fields, including research and development. However, concerns have been raised over hazardous properties due to their similar fiber shape to asbestos. Recent studies have shown that CNTs pose potential hazards which may cause fibrosis and/or lung inflammation similarly to asbestos. Methods: After intratracheal instillation of SWCNTs and MWCNTs to rats, pulmonary surfactant (PS) of the SWCNTs and MWCNTs was measured and analyzed using bronchoalveolar lavage fluid collected from the lung. After a single intratracheal instillation of SWCNTs and MWCNTs, phospholipid predominantly showed a significant increase compared to the control group, while proteins exhibited a significant increase both three days and one week after instillation. Results: As a result of surface tension, MWCNTs showed a significant decrease three days after treatment compared to the control group. In the case of the total cell number three days after instillation, MWCNTs revealed a temporarily significant increase when compared to the control group. For PMN number, when compared to the control group, SWCNTs displayed a significant increase throughout the observation period, while MWCNTs showed a significant increase three days and three months after treatment. Conclusions: After exposure to CNTs, the total cell number and PNT number, which indicate inflammatory response, were significantly increased. Therefore, this study suggests fiber–shaped CNTs may have a harmful effect on the lungs.
윤효정(Hyojung Yoon),서정관(Jungkwan Seo),김탁수(Taksoo Kim),김주현(Joohyun Kim),조아름(Areum Jo),이병우(Byeongwoo Lee),임현우(Hyunwoo Lim),이대엽(Daeyeop Lee),김필제(),최경희(Kyunghee Choi),양원호(Wonho Yang) 한국환경보건학회 2017 한국환경보건학회지 Vol.43 No.3
Objectives: Children may be more exposed to certain environmental contaminants because they react with greater sensitivity and have different food intakes and breathing rate per unit of body weight compared to adults. The aim of this study was to determine general exposure factors such as skin surface area, period and frequency of exposure, and others among Korean children aged ≤ 18 years old. This study was carried out as the first of its kind in Korea. Methods: We developed 23 recommended exposure factors for Korean children aged 0 to 18 years by reclassifying raw data from the National Health and Nutrition Examination Survey and the National Statistical Information Service, as well as through investigation by experiments in the absence of related data. Results: Reflecting the activity patterns of about 9,000 children, the daily inhalation rates for long-term exposure ranged from 9.49 m 3 /day for children from birth to <2 years to 14.98 m 3 /day for children aged 16 to <18 years. The research found that Korean children spent an average of 22.21 hours indoors, 0.67 hours outdoors, and 1.12 hours in-transit every day. Young children (≤ 2 years old) spent approximately 34 more minutes outdoors on weekends than they did on weekdays. Conclusion: Various physiological variables in the human body reflect characteristics of children that can directly influence risk exposure. Therefore, the identification of general exposure factors based on Korean children is required for appropriate risk assessment.
어린이들의 비의도적 행위에 대한 노출계수 개발 및 영향요인 분석
정다영(),윤효정(Hyojung Yoon),양원호(Wonho Yang),김탁수(Taksoo Kim),서정관(JungKwan Seo),허정(Jung Heo),류현수(Hyunsoo Ryu),김순신(Sunshin Kim),최민지(Min-Ji Choi) 한국환경보건학회 2017 한국환경보건학회지 Vol.43 No.5
Objectives: The purpose of this study was to develop exposure factor data for the Korean child population, with a specific focus on behavior characteristics such as hand-to-mouth and object-to-mouth and an analysis of influential factors. Methods: We divided environments into two places, which were house/indoor and nursery. A total of 400 children (house/indoor) and a total of 162 children (nursery) were recruited from the cities of Seoul, Incheon, Daegu, and Gwangju. The children were divided into two groups. We conducted direct measurement by using one hour of videotaping alongside questionnaire surveys. This was performed to calculate behavior rates, such as how many children perform hand-to-mouth and object-to-mouth behaviors. Results: The respective average frequencies of hand-to-mouth and object-to-mouth were 0.8±2.23 and 0.82±2.64 contacts/hr for house/indoor. The respective average frequencies of hand-to-mouth and object-tomouth were 2.87±4.63 and 1.47±3.84 contacts/hr in the nursery group. For the mouthing participants, the average frequencies of hand-to-mouth and object-to-mouth were 3.31 and 3.20 contacts/hr in house, and 4.80 and 3.26 in nursery. Compared to other countries such as the USA, the frequencies of hand-to-mouth and object-tomouth behaviors found in this study were relatively lower. Conclusions: Children have the potential for exposure to toxic substances through non-dietary ingestion pathways by mouthing objects or their fingers. In this study, the mouthing frequency was relatively lower than that found in Western countries. This can be explained that mouthing behaviour may be affected by culture and lifestyle characteristics.