• 한국환경보건학회지
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• 제45권3호
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• pp.247-257
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• 2019

Objectives: The Korea Ministry of Environment regulates concentrations of hazardous air pollutants (HAPs) through Atmosphere Environmental Standards to protect public health from HAPs. However, simply determining the exceedance of HAP concentrations has several limitations and more comprehensive assessment is required. In addition, integrated risk assessment is needed considering exposure in all microenvironments, including outdoor as well as indoor environments. The purpose of this study was to assess the differences in risk by sub-population groups according to time-activity patterns and reported concentrations, as well as the lifetime risk for Koreans. Methods: In this study, we calculated time-weighted average exposure concentrations for benzene and $PM_{10}$ among preschool-age children, students, housewifes, workers, and the elderly using residential time and concentrations for indoor (house, school or workplace, other), outdoor, and transport by the meta-analysis method. The risk assessments were conducted by excess cancer risk and disease death risk using 1,000,000 Monte-Carlo simulations for probabilistic analysis. Results: Preschool-age children, students, housewifes, workers, and the elderly spent 91.9, 86.0, 79.8, 82.2, and 77.3% of their day in their house, workplace, or school, respectively. The more than 99% excess cancer risk for benzene exceed 1.0E-06 in all sub-populations and lifetime. The acute disease death risk for $PM_{10}$ for housewifes and workers for lifetime were 3.35E-04 and 3.18E-04, and chronic disease death risks were 2.84E-03 and 2.70E-03, respectively. Conclusions: The risk of benzene and $PM_{10}$ by sub-population group and for the lifetime of housewifes and workers were assessed. Benzene showed risky results for this study. All disease death risks of $PM_{10}$ were higher than 1.0E-04 and showed different risks by sub-population. This study can be used as a basis for lifetime exposure and risk assessment to benzene and $PM_{10}$.

• 한국광물학회지
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• 제24권1호
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• pp.43-53
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• 2011

폐석면 광산의 위해성 평가는 통상 ABS 방식에 의해 이루어지지만, 조사지역 전반에 관한 위해성 경향을 파악하는 데 그치는 한계를 지닌다. 이 연구에서는 새로운 평가방식으로 잠재적 위해지수(PIHR)라는 개념을 도입하여 석면 위해도를 계랑화하였다. PIHR 값에 대해 석면이 인체에 위해를 주는 요인들을 고려하여 적절한 가중치를 부여한 후, 토양 내 석면 농도 값을 적용하여 지리정보시스템(GIS)의 적지선정기법을 활용하여 위해성 평가를 실시하였다. 충청남도 보령시에 위치한 어느 폐석면 광산에 적용한 결과, 잠재적 위해 지수가 매우 높은 지역은 전체 면적의 7.8%에 해당되는 27.3 ha이며, 위해성 평가는 미국 환경보호청의 종합위해정보시스템(IRIS) 모델을 적용하여 각각 만 명당 1명(석면농도 0.36% 이상), 3만 명당 1명(석면농도 0.1% 이상), 10만 명당 1명(석면농도 0.04% 이상) 평생초과 발암 위험도 기준으로 관리할 경우 3.0, 12.9, 19.5 ha로 면적이 증가한다. 이러한 결과는 향후 광해 복원범위 선정에 효과적으로 적용할 수 있다.

• 한국환경보건학회지
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• 제47권4호
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• pp.366-377
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• 2021

Background: Polycyclic aromatic hydrocarbons (PAHs) are generated in petrochemical complexes, can spread to residential areas and affect the health of residents. Although harmful PAHs are mainly present in particle phase, gas phase PAHs can generate stronger toxic substances through photochemical reaction. Therefore, the risk assessment for PAHs around the petrochemical complex should consider both particle and gas phase concentrations. Objectives: This study aimed to investigate the concentration characteristics of particle and gas phase PAHs by season in residential areas around petrochemical complexes, and to assess the risk of PAHs. Methods: Samples were collected for 7 days by seasons in 2014~2015 using a high volume air sampler. Particle and gas phase PAHs were sampled using quartz filter and polyurethane foam, respectively, analyzed by GC-MS. Chronic toxicity and probabilistic risk assessment were performed on 14 PAHs. For chronic toxicity risk assessment, inhalation unit risk was used. Monte-Carlo simulation was performed for probabilistic risk assessment using the mean and standard deviation of measured PAHs. Results: The concentration of particle total PAHs was highest in autumn. The gas phase concentration was highest in autumn. The average gas phase distribution ratio of low molecular weight PAHs composed of 2~3 benzene rings was 85%. The average of the medium molecular weight composed of 4 benzene rings was 53%, and the average of the high molecular weight composed of 5 or more benzene rings was 9%. In the chronic toxicity risk assessment, 7 of the 14 PAHs exceeded the excess carcinogenic risk of 1.00×10^-6. In the Monte-Carlo simulation, Benzo[a]pyrene had the highest probability of exceeding 1.00×10^-6, which was 100%. Conclusions: The concentration of PAHs in the residential area around the petrochemical complex exceeded the standard, and the excess carcinogenic risk was evaluated to be high. Therefore, it is necessary to manage the air environment around the petrochemical complex.

• 한국대기환경학회지
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• 제12권5호
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• pp.567-576
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• 1996

Air pollution has been recognized for many years as a factor which heightens the risk of cancer. Extractable polycyclic organic matters in air particulates have been recognized as to have carcinogenic effects. This study examined the health risks posed by organic substances of air particulates in Seoul based on methodelogies that have been developed for conducting risk posed by organic substances of sir particulates in Seoul based on methodologies that have been developed for conducting risk assessment of complex -chemical-mixture. The data used in this study was obtained from air samples collected in a heavy traffic area of Seoul (Shinchon) from 1986 to 1994. The mean concentration of total supended pariculates was 158.0.mu.g/m/msup 3/, 5% of which is consisted of organic matter. The excess cancer risk from benzo(a)pyrene (BaP) was estimated to be 3.48.times.10$^{-6}$ by applying BaP unit risk estimates to the mean concentration. 8.74ng/m BaP equivalents of potency method was 1.0.times.10$^{-3}$ . The calculated risk from EOM were comparably higher than that from benzo(a)pyrene and exceeded the acceptable risk level.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.44.1-44.11
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• 2023

Background: A series of breast cancer cases were recently reported in a tertiary university hospital in South Korea. Nurses are generally exposed to risk factors for breast cancer such as night shift work, antineoplastic agents, and job strain. However, the epidemiological evidence of excess incidence among nurses remains lacking. This study aims to investigate the excess incidence of breast cancer among nurses in a tertiary university hospital and provide epidemiological evidence of occupational risk factors. Methods: A retrospective cohort was developed using personnel records of female workers in the nursing department who worked from January 2011 to June 2021 in a tertiary university hospital in South Korea. Sick leave records were used to identify cases of breast cancer. The standardized incidence ratio of breast cancer among nurses was compared to the general population. Results: A total of 5,509 nurses were followed up for 30,404 person-years, and 26 breast cancer cases were identified. This study revealed a significantly increased breast cancer incidence among all included nurses, with a standardized incidence ratio of 1.65 (95% confidence interval [CI]: 1.08-2.41), compared to the general population. Workers, who handle antineoplastic agents in their representative department and current and/or former department, had significantly elevated breast cancer standardized incidence ratios of 2.73 (95% CI: 1.008-5.94) and 3.39 (95% CI: 1.46-6.68), respectively. Conclusions: This study provides significant evidence of increased breast cancer risk among nursing staff in a hospital setting, particularly those who handle antineoplastic drugs. Measures that reduce exposure to risk factors should be implemented, especially anticancer drugs, to protect healthcare professionals. Further research at a national level that focuses on healthcare workers is necessary to validate breast cancer incidence and its contributing factors.

• Journal of Radiation Protection and Research
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• 제46권1호
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• pp.14-23
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• 2021

Background: For radiological protection and control, the International Commission on Radiological Protection (ICRP) provides the nominal risk coefficients related to radiation exposure, which can be extrapolated using the excess relative risk and excess absolute risk obtained from the Life Span Study of atomic bomb survivors in Hiroshima and Nagasaki with the dose and dose-rate effectiveness factor (DDREF). Materials and Methods: Since it is impossible to directly estimate the radiation risk at doses less than approximately 100 mSv only from epidemiological knowledge and data, support from radiation biology is absolutely imperative, and thus, several national and international bodies have advocated the importance of bridging knowledge between biology and epidemiology. Because of the accident at the Tokyo Electric Power Company (TEPCO)'s Fukushima Daiichi Nuclear Power Station in 2011, the exposure of the public to radiation has become a major concern and it was considered that the estimation of radiation risk should be more realistic to cope with the prevailing radiation exposure situation. Results and Discussion: To discuss the issues from wide aspects related to radiological protection, and to realize bridging knowledge between biology and epidemiology, we have established a research group to develop low-dose and low-dose-rate radiation risk estimation methodology, with the permission of the Japan Health Physics Society. Conclusion: The aim of the research group was to clarify the current situation and issues related to the risk estimation of low-dose and low-dose-rate radiation exposure from the viewpoints of different research fields, such as epidemiology, biology, modeling, and dosimetry, to identify a future strategy and roadmap to elucidate a more realistic estimation of risk against low-dose and low-dose-rate radiation exposure.

• Communications for Statistical Applications and Methods
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• 제29권3호
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• pp.287-299
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• 2022

In radiation epidemiology, the excess relative risk (ERR) model is used to determine the dose-response relationship. In general, the dose-response relationship for the ERR model is assumed to be linear, linear-quadratic, linear-threshold, quadratic, and so on. However, since none of these functions dominate other functions for expressing the dose-response relationship, a Bayesian semiparametric method using splines has recently been proposed. Thus, we improve the Bayesian semiparametric method for the selection of the tuning parameters for splines as the number and location of knots using a Bayesian knot selection method. Equally spaced knots cannot capture the characteristic of radiation exposed dose distribution which is highly skewed in general. Therefore, we propose a nonparametric Bayesian knot selection method based on a Dirichlet process mixture model. Inference of the spline coefficients after obtaining the number and location of knots is performed in the Bayesian framework. We apply this approach to the life span study cohort data from the radiation effects research foundation in Japan, and the results illustrate that the proposed method provides competitive curve estimates for the dose-response curve and relatively stable credible intervals for the curve.

• 한국가스학회지
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• 제22권6호
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• pp.16-27
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• 2018

대한민국 정부에서 2014년부터 LPG배관망과 LPG소형탱크를 도시가스 공급망 개설이 어려운 산간이나 도서지역에 보급하는 사업을 시작했다. 마을단위와 군단위로 LPG집단공급시설을 설치하면서 기존의 가스공급 압력이 아닌 10배 이상의 높은 준저압(25kPa~100kPa)으로 소비자에게 공급하게 되면서 가스사고의 위험성이 높아졌다. 기존의 가스공급압력보다 10배 이상 높은 압력이기 때문에 가스가 누출 되었을 때 빠른 속도로 많은 양이 누출하게 된다. 이에 준저압 가스배관의 안전성 확보를 위해 과류차단밸브가 필요하게 되었지만, 국내에서는 준저압 매몰배관용 과류차단밸브가 미개발되어 있으며 보급 또한 되어 있지 않는 상황이다. 이에 한국가스안전공사에서는 과류차단밸브의 국산화를 위해 과류차단밸브를 기개발한 해외의 성능기준과 제품을 조사 중에 있으며, 과류차단밸브의 성능평가를 위해 성능시험설비를 구축하여 준저압 연료가스 매몰배관용 과류차단밸브를 연구 개발 중에 있다.

• 상하수도학회지
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• 제23권1호
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• pp.57-67
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• 2009

Under the supply-oriented policy, efficiency and rationale have not been fully considered in planning of water supply facilities in Korea. As a case, this study shows that large-size systems are suffering from overcapacity problem of water treatment plants, and thus discusses what options should be applied to deal with inefficiency. Water demand of large-size systems has suddenly decreased for the last 10 years while water demand has been often assumed to increase at a regular rate in planning of plants according to excess capacity hypothesis. This inconsistency led to a serious overcapacity. In 2006, total excess capacity of nine large-size systems was more than 1.2 times as large as maximum daily demand of total customers in Seoul. However, their options are expected to stay ex post facto. To prepare the risk of overcapacity, and draw large benefits out of the plants, the authors and other professionals in Korea should further discuss the more adaptive method for prediction of water demand, and systems integration between a large-size system and adjoining systems.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.325-336
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• 2019

The activity concentrations of $^{226}Ra$, $^{232}Th$, and $^{40}K$ from 102 building materials samples were determined using a high-purity germanium (HPGe) detector. The activity concentrations were evaluated for possible radiological hazards to the human health. The excess lifetime cancer risks (ELCR) were also estimated, and the average values were recorded as $0.42{\pm}0.24{\times}10^{-3}$, $3.22{\pm}1.83{\times}10^{-3}$, and $3.65{\pm}1.85{\times}10^{-3}$ for outdoor, indoor, and total ELCR respectively. The activity concentrations were further subjected to RESRAD-BUILD computer code to evaluate the long-term radiation exposure to a dweller. The indoor doses were assessed from zero up to 70 years. The simulation results were $92{\pm}59$, $689{\pm}566$, and $782{\pm}569{\mu}Sv\;y^{-1}$ for indoor external, internal, and total effective dose equivalent (TEDE) respectively. The results reported were all below the recommended maximum values. Therefore, the radiological hazards attributed to building materials under study are negligible.