• 지질공학
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• 제19권3호
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• pp.295-306
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• 2009

본 연구는 지하수, 토양, 대기의 노출경로에 따라서 부산광역시 사상공단의 지하수와 토양이 인체와 환경에 미치는 영향을 평가하였다. 토양과 대기의 노출경로에 따른 발암 위해는 나타나지 않았으나, 지하수에서는 TCE와 PCE의 발암 위해성이 각각의 기준 한계값인 1.0E-6과 1.0E-5에 대해서 각각 6.7E-6과 1.0E-5로 나타나 발암 위해가 있는 것으로 판단되었다. 대기에서는 비발암성 위해가 나타나지 않았다. 토양의 위해계수와 위해지수는 각각 3.4E-5와 5E-5로서 기준 한계값(1.0) 보다 낮게 나타났으나, 지하수의 위해계수와 위해지수는 각각 0.7 (위해성이 없음)과 1.4(위해성이 있음)로 나타났다. TCE의 최소성분감소비(CRF)는 2.5로서 TCE의 정화작업이 요구된다. 18개의 노출인자에 대한 민감도 분석 결과, 8개의 노출 인자(비 발암 물질에 대한 평균 수명, 발암 물질에 대한 평균 수명, 체중, 노출기간, 노출빈도, 피부노출빈도, 토양 섭취율, 물 섭취율)의 변화에 따라서 위해도가 변화하는 것으로 나타났다.

• 환경영향평가
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• 제30권6호
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• pp.413-424
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• 2021

현행 환경영향평가 내 건강영향평가는 단일 물질별 기준초과 여부를 평가하고 적정 저감방안을 수립하도록 시행된다. 이에 따라 일부 개발 대상사업의 경우, 위해성평가의 모든 물질이 기준을 만족하지만 노출농도가 기준에 매우 근사한 경우가 존재한다. 하지만 여기서 모든 물질들의 동시 노출을 고려한다면 건강영향은 단일 물질별 관리보다 상당히 크게 발생할 여지가 있다. 실제로 수용체에 노출되는 건강영향을 파악하기 위해 배출물질의 통합평가 방법론의 구체화 및 개선방안 마련이 필요하다. 본 논문은 해외 선진사례 및 국내외 문헌고찰을 통해 누적위해성평가 및 위해성의 통합기법에 대한 개념을 정의하고, 산업단지 개발 시 다물질에 대한 건강영향을 고려한 누적위해성평가 활용을 위한 방법론을 제안하였다. 제안된 방법론을 통해 산업단지에 배출되는 유해중금속 4종(Ni, Cr⁶⁺, Cd, As)에 대한 통합지표를 산출하였으며, 과거 10년(2011~2020년) 간 수행된 산업단지 개발사업에 대한 사례적용을 통해 활용성을 확보하였다.

• Toxicological Research
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• 제17권
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• pp.47-57
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• 2001

Alzheimer's disease (AD) is the most common cause of dementia in the elderly, and its pathology is characterized by the presence of numerous numbers of senile plaques and neurofibrillary tangles. Several genetic and transgenic studies have indicated that excess amount of $\beta$-amyloid protein (A$\beta$) is produced by mutations of $\beta$TEX>$\beta$-amyloid precursor protein and causes learning impairment. Moreover, $A\beta$ has a toxic effect on cultured nerve cells. To prepare AD model animals, we have examined continuous (2 weeks) infusion of $A\beta$ into the cerebral ventricle of rats. Continuous infusion of $A\beta$ induces learning impairment in water maze and passive avoidance tasks, and decreases choline acetyltransferase activity in the frontal cortex and hippocampus. Immunohistochemical analysis revealed diffuse depositions of $A\beta$ in the cerebral cortex and hippocampus around the ventricle. Furthermore, the nicotine-evoked release of acetylcholine and dopamine in the frontal cortex/hippocampus and striatum, respectively, is decreased in the $A\beta$-infused group. Perfusion of nicotine (50 $\mu\textrm{M}$) reduced the amplitude of electrically evoked population spikes in the CA1 pyramidal cells of the control group, but not in those of the $A\beta$-infused group, suggesting the impairment of nicotinic signaling in the $A\beta$-infused group. In fact, Kd, but not Bmax, values for ［$^3H$］ cytisine binding in the hippocampus significantly increased in the $A\beta$-infused rats. suggesting the decrease in affinity of nicotinic acetylcholine receptors. Long-term potentiation (LTP) induced by tetanic stimulations in CA1 pyramidal cells, which is thought to be an essential mechanism underlying learning and memory, was readily observed in the control group, whereas it was impaired in the $A\beta$-infused group. Taken together, these results suggest that $A\beta$ infusion impairs the signal transduction mechanisms via nicotinic acetylcholine receptors. This dysfunction may be responsible, at least in part, for the impairment of LTP induction and may lead to learning and memory impairment. We also found the reduction of glutathione- and Mn-superoxide dismutase-like immunoreactivity in the brains of $A\beta$-infused rats. Administration of antioxidants or nootropics alleviated learning and memory impairment induced by $A\beta$ infusion. We believe that investigation of currently available transgenic and non-transgenic animal models for AD will help to clarify the pathogenic mechanisms and allow assessment of new therapeutic strategies.

• Applied Microscopy
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• 제37권2호
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• pp.73-82
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• 2007

다지류 노래기의 안테나는 다양한 환경 자극을 감지하는 탁월한 기능을 가지고 있다. 안테나의 구조적 특성은 감각하는 자극의 종류와 밀접한 연관을 가지고 있으므로 본 연구는 띠노래기목의 평안노래기(Cawjeekelia pyongana)를 실험재료로 하여 다지류 안테나 표면의 미세구조를 주사전자현미경(FESEM)으로 관찰하였다. 노래기의 안테나는 8개의 마디로 이루어져 있었고, 큐티클의 표면에는 후각과 기계적 감각을 담당하는 다양한 종류의 감각기들이 형성되어 있었다. 평안노래기 안테나의 감각기들은 말단마디에 형성된 4개의 대형 원추말단(Ac) 감각기와 관상 감각모(Ts), 모상 감각모(Cs), 추상 감각모(Bs) 등 3종류의 감각모들로 이루어져 있음이 확인되었다. 관상 감각모는 제1마디를 제외한 전체 마디에 걸쳐 관찰되었고, 모상 감각모는 제4마디부터 제7마디까지, 그리고 추상 감각기는 제5마디부터 제7마디까지의 표면 함몰부에서만 관찰되었다. 추상 감각기는 그 미세구조적 특징에 따라 길이가 긴 제1형$(Bs_1)$과 길이가 짧은 제2형$(Bs_2)$, 가시 모양의 제3형$(Bs_3)$으로 다시 세분되었다. 제1형은 제5마디에만 분포되어 있었고, 제2형은 제5마디 및 제6마디에, 그리고 제3형은 제7마디에만 분포되어 있음이 확인되었다.

• The Korean Journal of Physiology and Pharmacology
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• 제11권1호
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• pp.1-7
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• 2007

Altered environmental gravity, including both hypo- and hypergravity, may result in space adaptation syndrome. To explore the characteristics of this adaptive plasticity, the expression of immediate early gene c-fos mRNA in the vestibular related tissues following an exposure to hypergravity stimulus was determined in rats. The animals were subjected to a force of 2 g (twice earth's gravity) for 1, 3, or 12 h, and were examined poststimulus at 0, 2, 6, 12, and 24 h. RT-PCR (reverse transcription polymerase chain reaction) and real-time quantitative RT-PCR were adopted to analyze temporal changes in the expression of c-fos mRNA. The hypergravity stimulus increased the expression of c-fos mRNA in the vestibular ganglion, medial vestibular nucleus, inferior vestibular nucleus, hippocampus, cerebellum, and cortex. The peak expression occurred at 0 h poststimulation in animals stimulated with hypergravity for 1 h, and at 6 h poststimulus in those stimulated for 3 h. In contrast, those stimulated for 12 h exhibited dual peaks at 0 and 12 h poststimulus. Bilateral labyrinthectomy markedly attenuated the degree of c-fos mRNA expression. Glutamate receptor antagonist also dramatically attenuated the degree of c-fos mRNA expression. These results indicate that expression of c-fos mRNA in response to hypergravity occurs in the vestibular related tissues of the central nervous system, in which peripheral vestibular receptors and glutamate receptors play an important role. The temporal pattern of c-fos mRNA expression depended on the duration of the hypergravity stimulus.

• 한국환경보건학회지
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• 제33권2호
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• pp.123-131
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• 2007

Many environmental contaminants including several metals, polycyclic aromatic hydrocarbons, and pharmaceuticals, have been identified to be phototoxic in the water environment. Concerns regarding photo-enhancement of toxicity of several environmental contaminants have been increasing because of the increased level of ultraviolet irradiation on the earth surface. However, there exist arguments that there might be certain defense mechanisms taking place in the aquatic ecosystem, which may include behavioral characteristics or genetic acclimation. This study was conducted to understand the potential responses of aquatic receptors to several phototoxic metals in the real environment, where long-term acclimation of such organisms to low dose UV-B may take place. For this purpose, water flea Daphnia magna was acclimated to environmentally relevant dose of UV-B (12 to $18uW/cm^2$) for >11 generations. The differences in developmental and life history characteristics, and toxicity responses were evaluated. Acclimation did not affect the daphnids' growth, longevity, and reproduction characteristics such as time to first brood, and brood size: After 21 d, survival of D. magna was not influenced by UV-B acclimation. When the number of young per female was compared. the daphnids acclimated for 11 generations tend to produce less number of neonates than the un-acclimated individuals but with no statistical significance (p>0.05). Four metals that were reported to be phototoxic elsewhere were employed in this evaluation, that include As, Cd. Cu, and Ni. UV-B level being applied in acclimation did increase the toxicity of Cd and Cu, significantly (p<0.05). However, the toxicities of As and Ni were not affected by irradiation of UV-B. Phototoxic responses were evaluated between the acclimated and the un-acclimated daphnids. For Cu, UV-B acclimation led to reduction of the photo-induced toxicity $(p\approx0.1)$ in daphnids. Non-acclimated Daphnia were affected by 50% at 4.18 ug/l Cu. but UV-B acclimated individuals exhibited $EC_{50}$ of 5.89 ug/l. With Cd, UV-B acclimation appeared to increase phototoxicity (p>0.05). With As and Ni, UV-B acclimation did not influence photo-induced toxicity. This observation may be in part explained by the type of reactive oxygen species that were generated by each metal. Similar to UV-B light, Cu is known to generate superoxide anion by acting as redox cycling toxicant. This is one of the first studies that employed_laboratory based UV-B acclimated test species for photoenhanced toxicity evaluation.

• 한국환경보건학회지
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• 제31권6호
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• pp.457-466
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• 2005

Industrial plasticizers such as phthalates can induce peroxisome proliferation. A growing concern among environmental and health groups has arisen because phthalates such as di-2-ethy1hexy1 phthalate (DEHP) and DBP may cause hormonal disorders, reproductive toxicity, hepatocellular tumors, genital disorders owing to a capacity to bind estrogen receptors, and a low-dose toxic action during certain periods of fetal development. Phthalate esters are used extensively as a plasticizer for plastic manufacture such as PVC bags and medical devices. This study investigated the effects of leached components from spring water container's cap and seal film. Phthalates, e.g. dimethy1 phthalate (DMP), diethy1 phthalate (DEP), di-n-buty1 phthalate (DBP), benzy1buty1 phthalate (BBP), di-(2-ethy1hexy1) phthalate (DEHP), and bisphenol A (BPA) were measured in the spring water. The bisphenol A was not detected or below the detection limit on the leaching from cap, sealing or spring water. DEHP were detected 90-116 ppb on the leaching from seal after 2 weeks, and 0.48-0.51 ppb from the spring water after I week. BBP were measured from seal within 1 week 25.4-66 ppb and below 0.12 ppb from spring water within 2 days. DMP were detected from seal within 2 weeks 51-68.5 ppb and 0.12 ppb after 2 weeks. DEP were measured from seal within 2 weeks 48.1-141 ppb and the concentrations were increased by the time from 0.10 to 0.31 ppb at spring water. DBP were detected from the seal within 2 weeks 92.3-5100 ppb and the concentration were decreased by the time from 0.24 to 0.10 ppb at spring water. These results indicate that some phthalate esters contaminated with spring water using the intact cap and seal film. It is concluded that the measured levels of phthalates leaching from these materials might in vivo only be slightly less than 1/10 of the LOAEL.

• Tuberculosis and Respiratory Diseases
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• 제78권2호
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• pp.99-105
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• 2015

Background: Aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, binds to a wide variety of synthetic and naturally occurring compounds. AhR is involved in the regulation of inflammatory response during acute and chronic respiratory diseases. We investigated whether nuclear receptor coactivator 7 (NCOA7) could regulate transcriptional levels of AhR target genes and inflammatory cytokines in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-treated human bronchial epithelial cells. This study was based on our previous study that NCOA7 was differentially expressed between normal and chronic obstructive pulmonary disease lung tissues. Methods: BEAS-2B and A549 cells grown under serum-free conditions were treated with or without TCDD (0.15 nM and 6.5 nM) for 24 hours after transfection of pCMV-NCOA7 isoform 4. Expression levels of cytochrome P4501A1 (CYP1A1), IL-6, and IL-8 were measured by quantitative real-time polymerase chain reaction. Results: The transcriptional activities of CYP1A1 and inflammatory cytokines were strongly induced by TCDD treatment in both BEAS-2B and A549 cell lines. The NCOA7 isoform 4 oppositely regulated the transcriptional activities of CYP1A1 and inflammatory cytokines between BEAS-2B and A549 cell lines. Conclusion: Our results suggest that NCOA7 could act as a regulator in the TCDD-AhR signaling pathway with dual roles in normal and abnormal physiological conditions.

• 한국환경보건학회지
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• 제44권3호
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• pp.217-226
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• 2018

Objectives: Despite the positive effects of Off-site risk assessment (ORA) system such as prevention of chemical accidents, some problems have been constantly raised. The purpose of this study is to analyze the problems that have occurred through the implementation of the ORA system for the past three years and to suggest reasonable directions for improvement in the future. Methods: In order to identify the problems with the methodology and procedure of ORA system, we analyzed statutes, administrative rules and documents related to the ORA system. A survey of ORA reviewers in National Institute of Chemical Safety was conducted to investigate the weight of determinants considered when judging the level of total risk in ORA. Results: In this study, we found out the uncertainty of the estimation of the number of people in the impact range in the procedure of the risk assessment of individual handling facilities, the lack of quantitative risk analysis methods for environmental receptors, and the ambiguity of the criteria for the total risk. In addition to suggesting solutions to the problems mentioned above, we also, suggested a decision tree for total risk in ORA. Conclusion: We anticipate that the solutions including the systematic decision tree for total risk suggested will contribute to the smooth operation of the ORA system.

• 환경영향평가
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• 제27권2호
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• pp.194-202
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• 2018

국내 법적인 건강영향평가로서 환경영향평가 내 위생 공중보건 항목의 평가는 특정 개발 사업에서 배출되는 유해대기오염물질 배출량 및 주변 주요 지점의 노출농도 산정, 이를 활용한 위해성 평가로 진행되고 있다. 하지만 개발 사업부지 주변의 노출 가능한 인구집단 규모를 고려하지 못하는 등 개발 사업부지 주변의 수용체 특성은 해당 위해성 평가에서 제대로 반영되지 못하고 있다. 본 논문의 목적은 개발 사업부지 주변의 노출 가능한 인구수를 산정 반영한 위해성 평가를 위해 잠재노출 인구수의 산정 및 이를 실제 위생 공중보건 항목 작성 시 활용하는 방안을 제안하는 것이다. 개발 사업부지 주변의 인구수 산정 관련한 국내 자료 현황을 파악하고 이를 고려한 잠재노출 인구수 산정 알고리즘을 제안하였다. 나아가 산업단지 개발 시 유해대기오염물질 배출을 가정한 사례 분석을 수행하였다. 잠재노출 인구수를 활용한 위해성 평가는 인구집단 위해도 개념이 적용되어야 함을 제시하였으며, 향후 연구로 평가결과에 대한 건강영향 여부의 판단기준 설정이 요구됨을 제안하였다. 또한 본 논문의 잠재노출 인구수 산정방법을 통해 개발사업의 입지제한 도구로의 활용가능성을 제안하였다. 이번 논문은 위생 공중보건 항목 작성 시 개발 사업부지 주변의 수용체 특성을 반영한 위해성 평가를 수행하는 방안을 제시했다는 것에 의미가 있다.