• 한국환경보건학회지
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• 제49권4호
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• pp.210-217
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• 2023

Background: N-nitrosamines are carcinogenic substances often found in rubber products. They are produced when certain additives of rubber products react with nitrite in saliva or air. Exposure assessment for the proper management and communication of N-nitrosamines in rubber balloons should be carried out. Objectives: This study was conducted to determine the concentrations of N-nitrosamines in rubber balloons in the South Korean market and assess exposure among Korean children. Methods: Forty eight rubber balloon products in the domestic market were purchased and a total of 68 balloons were analyzed for N-nitrosamines and N-nitrosatable substances. Chemical analysis was conducted by HPLC-MS/MS according to the method EN 71-12. For exposure assessment, an exposure algorithm and coefficients were obtained from previous studies. Results: Among the 68 rubber balloons, N-nitrosamines were detected in 18 (26.5%) with an average level of 60.77 ㎍/kg. N-Nitrosatable substances were detected in 44 products (64.7%) with an average level of 1353.33 ㎍/kg. As a result of the exposure evaluation, the exposure dose differed according to how exposure coefficients were applied. The median exposure (50th percentile) was higher in the age group of 6~12 years, and high exposure (95th percentile) was higher in the age group of 13~18. Conclusions: We evaluated the N-nitrosamines contained in rubber balloons purchased in the domestic market and assessed oral exposure among South Korean children. For integrated risk management of N-nitrosamines, further studies and discussion regarding exposure and risk assessment are required.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2006년도 추계학술대회
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• pp.34-45
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• 2006

Chemical toxicants are metabolically converted to numerous metabolites in the body. Toxicokinetic characteristics of metabolites could be therefore used as biomarker of exposure for human risk assessment. Biologically based dose response (BBDR) model was proposed for future direction of risk assessment. However, this area has not been developed well enough for human application. Benzo(a)pyrene (BP), for example, is a well-known environmental carcinogen and may produce more than 100 metabolites and BPDE-DNA adduct, a covalently bound form of DNA with benzo(a)pyrene diolepoxides (BPDES), has been applied to qualitatively or quantitaively estimate human exposure to BP. In addition, di(2-ethylhexyl) phthalate (DEHP), a widely used plasticize. in the polymer industry, is one of endocrine-disrupting chemicals (EDCs) and has been monitored in humans using urinary or serum concentrations of DEHP or its monomer MEHP for exposure and risk assessment. However, it is difficult to estimate the actual level of toxicants using these biomarkers in humans using. This presentation will discuss a methodology of exposure and risk assessment by application of metabolic profiling kinetics.

• 한국환경보건학회지
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• 제49권3호
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• pp.159-168
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• 2023

Background: An ongoing environmental exposure assessment of humidifier disinfectants (HDs) has been conducted since November 2011 among individuals who experienced HD exposure-related adverse health effects. It is being performed in order to determine and quantify exposure to humidifier disinfectants in victims and their families. To date, the assessment has encompassed Cycles I-to-V. There is no report summarizing the characteristics of the subjects from the overall cycles. Objectives: We intended to examine the individual characteristics related to demographics, HD usage, and HD exposure using integrated data from Cycles I-to-V of the environmental exposure assessment of HDs and the changes with the cycles. Methods: We included 7,543 individuals who participated in Cycles I-to-V of the environmental exposure assessment of HDs. We summarized the participants' characteristics regarding their demographics (e.g., sex, education level, and age), HD usage history (e.g., product name, ingredient, and frequency of HD use), and HD exposure (e.g., daily time of HD use, cumulative time of HD use, and exposure intensity). In addition, their characteristics were compared across the cycles of the exposure assessment. Results: Among the 7,543 participants from Cycles I-to-V, there were more male participants than females (51.05% overall), except for Cycles I and III. Across all cycles, a higher proportion of survivors was observed than deceased individuals. While PHMG was the most prevalent ingredient in HDs throughout all the cycles, its proportion gradually decreased over the course of the examination cycles. Participants in Cycle I reported longer daily times of HD use compared to those in the subsequent cycles. On the other hand, cumulative time of HD use was shorter in the earlier cycles than in the later cycles. Conclusions: Using the integrated data from the full cycles of the environmental exposure assessment, this study identified changes in demographic characteristics as well as the HD exposure characteristics between the participants across different cycles.

• Molecular & Cellular Toxicology
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• 제3권3호
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• pp.185-189
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• 2007

Gene expression levels of choriogenin, vitellogenin and estrogen receptor were determined using Reverse transcription (RT)-PCR technique after exposure to estrogenic chemical bisphenol A in the Korean wild medaka (Oryzias sinensis). These genes have been known to be induced in male test fish when the fish are exposed to estrogenic chemicals. Therefore they can be suggested as a possible biomarker of endocrine disruption in fish, however, relatively little has been known about these genes expression by estrogenic chemicals in Korean wild fish. Mature male Oryzias sinensis were treated with bisphenol A at nominal concentrations of 0.02, 0.2 and 2 mg/L for 6 days and total RNA was extracted from the livers of treated fish for RT-PCR. When the five biomarker genes were amplified by RT-PCR in the same condition, mRNA induction level of each gene was elevated with different sensitivities. Conclusively, the results of this work indicated that measurement of vitellogenin and choriogenin using RT-PCR is effective as a simple tool for the screening of estrogenic chemicals and suggested that O. sinensis would be a suitable model fish for the environmental risk assessment of potential endocrine disruptors.

• 한국환경보건학회지
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• 제48권2호
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• pp.75-85
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• 2022

Background: Various types of semi-volatile organic compounds (SVOCs) exist in the public's living environment. They occur in different forms in terms of their physical and chemical properties and partition coefficients. As a consequence, indoor exposure to SVOCs occurs via various routes, including inhalation of air and airborne particles, skin contact, and dust intake. Objectives: To propose a method for assessing human exposure to the SVOCs occurring in the air of an indoor environment, the concentrations of SVOCs in house dust and organic films measured in a real residential environment were estimated in terms of gas-phase concentration using the partition coefficient. Assessment of inhalation exposure to SVOCs was performed using this method. Methods: Phthalates were collected from samples of house dust and organic films from 110 households in a real residential environment. To perform an exposures assessment of the phthalates present in organic films, gas-phase concentration was calculated using the partition coefficient. The airborne gas-phase concentrations of phthalates from the house dust and organic films were estimated and exposure assessment was performed based on the assumption of inhalation exposure from air. Results: As a result of the exposure assessment for gas-phase phthalates from house dust and organic films, preschool children showed the highest level of inhalation of phthalates, followed by school children, adults, and adolescents. Conclusions: This study includes the limitation of not considering different SVOCs exposure pathways in the health impact assessment, including those of phthalates in the indoor living environment. However, this study has the significance of performing exposure assessment based on exposure to SVOCs present in indoor air that originated from organic films in the indoor residential environment. Therefore, the results of this study should be useful as basic data for exposure and health risk assessments of SVOCs associated with organic films in the indoor environment.

• 환경영향평가
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• 제18권1호
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• pp.11-19
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• 2009

We conducted human risk assessment due to inhalation exposure to heavy metals emitted from incinerator. The process of health impact assessment(HIA) on incinerator is as follows: The first step is to presume and calculate the amount of heavy metals emitted using emission factor. The second step is to conduct an exposure assessment using the K-SCREEN model which is used for predicting the concentration in a conservative method. The last step is to carry out a risk assessment on carcinogenic and non-carcinogenic substances. This study revealed that rank of carcinogenic human risk was $Cr^{+6}$ > As > Ni > Cd, and values of human risk assessment on carcinogenic and non-carcinogenic substances is lower than the US criteria for risk assessment except $Cr^{+6}$. It is expected that the technique of HIA, especially human risk assessment on heavy metals, would be applied to the incinerator construction project. In addition, more systematic studies are needed to overcome some weak points and limits found in this study.

• Environmental Analysis Health and Toxicology
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• 제20권4호통권51호
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• pp.375-383
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• 2005

염화제일철은 2004년 OECD SIDS 프로그램으로 한국에서 위해성평가가 수행된 대량생산 화학물질로 1998년 화학물질 유통량조사에 의하면 우리나라에서 연간 100,000톤이 생산되었다. 본 연구에서는 염화제일철의 인체 및 환경적 영향에 대한 독성잠재성을 평가하기 위하여 OECD테스트가이드라인에 따라 독성시험을 수행하였다. 인체영향을 확인하기 위한 급성경구독성시험과 급성경피독성시험에서 랫드의 반수치사량은 각각 300$\sim$2,000 mg/kg b.w.과 >2,000mg/kg b.w.이었다. 반복독성시험의 무유해용량 (NOAEL)은 수컷 랫드는 125mg/kg b.w./day, 암컷 랫드는 250mg/kg b.w./day였고, 생식 및 발생독성시험에서 무유해용량은 암수 랫드 모두 500mg/kg b.w./day로 관찰되었다. 약한 피부자극성을 보였으며, 안부식성 물질임이 관찰되었다. S. typhimurium과 E. coli 균주를 이용한 복귀돌연변이시험에서 최고 농도인 5,000$\mu$g/plate에서 유전독성을 보이지 않았으며, 마우스를 이용한 생체내 (in vivo)소핵시험에서도 최고 농도인 50mg/kg bw/day에서 소핵유발빈도의 증가를 보이지 않아 본 시험물질은 돌연변이 유발 물질이 아닌 것으로 평가되었다. 어류(Oryzis latipes), 물벼룩 (Daphnia magna), 조류 (Pseudokirchneriella subcapitata)를 이용한 수생생물에 대한 급성독성시험 결과, 96시간 Oryzias latires의 반수치사농도는 46.6 mg/L이었고, 48시간 Daphnia magna의 반수영향농도는 19.0 mg/L이었다. 또한 Pseudokirchneriella subcapitata의 72시간 반수영향농도는 성장률을 이용한 계산법으로 6.9mg/L이었으며, 면적계산법으로는 3.8mg/L의 성장저해가 관찰되었다. 어류와 조류의 경우는 부분적으로 pH의 변화에 따른 영향으로 평가할 수 있는데 어류시험에서 pH중성시험용액에서는 100mg/L이상의 독성값을 나타내었고, 조류에서는 농도 12mg/L이상에서 pH 7아래로 떨어짐을 확인할 수 있었다. 염화제일철은 생산 및 사용공정에서 작업자에게 흡입 혹은 피부로 노출될 가능성이 있으나 밀폐공간에서 사용되므로 노출이 적은 것으로 평가되었다. 3종의 수생생물의 독성결과로부터 염화제일철은 수생환경에서 중간정도의 해가 있으며, 우리나라에서는 직접적인 염화제일철의 소비자 노출은 없으나 환경중 노출이 우려됨에 따라 제19차 OECD대량생산화학물질 초기위해성평가회의에서 환경 분야에 대해서는 추가연구 후보물질로 권고되었고, 인체 분야에서는 인체에 대한 유해성과 사용 패턴을 고려하여 추가연구 우선순위가 낮은 물질로 권고되었다.

• 환경영향평가
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• 제10권3호
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• pp.211-221
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• 2001

Recognizing interaction between the environment and humans, the EIA(environmental impact assessment) movement has sought to promote more environmentally sound and informed decisions for the sake of human welfare. Therefore, most EIA programs require the consideration of human health impacts. Yet relatively few EIA documents adequately address those impacts. This study was carried out to investigate the role of EIA for reuniting the environment and human health, for preventing and reducing significant health risks, and for improving human health impact assessment by means of risk assessment. Risk assessment consists of 4 components; hazard identification, dose-response assessment, exposure assessment and risk characterization. Since most people spent their times in indoor, indoor air quality modelling can be used in exposure assessment and risk assessment. In this study, indoor $NO_2$ concentration and personal $NO_2$ exposure were estimated by Box Model using mass balance equation and time weighted average, respectively. The estimated indoor $NO_2$ concentration and the personal $NO_2$ exposure were compared by those measured, respectively. Subsequntly, health effect was assessed with these results. Consequently, exposure assessment and risk assessment using indoor air quality model may be considered to be applicable to EIA.

• 한국환경보건학회지
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• 제41권2호
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• pp.71-81
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• 2015

Objectives: Photochemical ozone pollution is associated with increased mortality risk. This study aims to assess the population exposure to ozone according to population characteristics for high ozone days in the Busan metropolitan region (BMR). Methods: The ozone exposure assessment in this study was performed using the WRF-CMAQ simulated ozone concentrations and the population data in the BMR. The settled and daytime population and their activity were considered to conduct the static and dynamic ozone exposure assessment. Results: Applying a static exposure assessment, in case that high ozone occurred throughout Busan area, the highest exposure levels were evaluated in urban neighborhoods. In case of ozone pollution in outer Busan, because sensitive groups have been relatively higher exposure, this case was also evaluated as part of that should not be overlooked. The dynamic exposure was higher than static exposure because the number of population exposed to ozone of high concentration is increased. This approach is important in a regard consider that daytime population distribution when high ozone occur. Conclusion: This study shows the different population exposure according to various ozone distributions for each episode day. Considering demographic characteristic such as population density and activity should be important to understanding the population exposure assessment when ozone pollution occurs.

• Safety and Health at Work
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• 제3권1호
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• pp.71-76
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• 2012

Malignant mesothelioma is an uncommon but rapidly fatal disease for which the principal aetiological agent is exposure to asbestos. Mesothelioma is of particular significance in Australia where asbestos use was very widespread from the 1950s until the 1980s. Exposure to asbestos includes occupational exposure associated with working with asbestos or in workplaces where asbestos is used and also 'take-home' exposure of family members of asbestos exposed workers. Asbestos exposure may also be nonoccupational, occurring as a consequence of using asbestos products in non-occupational contexts and passive exposure is also possible, such as exposure to asbestos products in the built environment or proximity to an environmental source of exposure, for example an asbestos production plant. The extremely long latency period for this disease makes exposure assessment problematic in the context of a mesothelioma registry. OccIDEAS, a recently developed online tool for retrospective exposure assessment, has been adapted for use in the Australian Mesothelioma Registry (AMR) to enable systematic retrospective exposure assessment of consenting cases. Twelve occupational questionnaire modules and one non-occupational module have been developed for the AMR, which form the basis of structured interviews using OccIDEAS, which also stores collected data and provides a framework for generating metrics of exposure.