• Toxicological Research
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• 제19권4호
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• pp.277-283
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• 2003

Polychlorinated biphenyls (PCBs) has been widely used as plasticizer, insulator, lubricant, paint and ink. The persistence of PCBs in the environment and their bioaccumulation in living organism make a raise concerns regarding their toxic effects in immune system and subsequent effects on human health. However little has been known about effect of PCB, an endocrine disrupter, on splenocytes. In this study, for identifying the effect on the organs and immune cell of mice by the concentration and time of commercial PCB mixture (Aroclor 1254), each 3 mice were tested at the concentration of 3, 30, 300, 1,000 mg/kg respectively, and their organ's weight were measured in 4, 7, 14 days, respectively. Also according to concentration and time, PCB was evaluated for the effects on splenocyte viability and lipopolysaccaride (LPS) and concanavaline A (Con A)-induced splenocyte proliferation on mice spleen. In liver and lung, there were significantly defferent by concentration and time of PCB (p < 0.0001). In respect of concentration of PCB, no significant effects on mice's liver by Aroclor 1254 concentration below than 300 mg/kg were observed except at the concentration of 1,000 mg/kg doses (p < 0.0001). But there was not significant different change in mice spleen by concentration and time of PCB (p=0.2206) and the mode of weight change of spleen was different to of liver and of lung. Viabilities of splenocytes were decreased following treatment with high concentration of PCB. Also, LPS and Con A-induced cell proliferations were decreased by Aroclor 1254 at 1,000 mg/kg. These data suggest that Aroclor 1254 is the immunotoxic compound that may have an effect on mouse immune system.

• 한국물환경학회지
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• 제24권6호
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• pp.758-766
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• 2008

먹는물 처리 전후 다이옥신류의 동족체 패턴 및 제거율을 평가하기 위해서 42개의 일본 정수처리장에서 2년간 122개의 시료를 채취해 dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) 및 coplanar polychlorinated biphenyls (Co-PCBs)를 분석하였다. 다이옥신류의 평균 농도와 독성등가값 (toxic equivalent, TEQ)은 원수와 처리수에서 각각 60.24 pg/L (0.14 pg-WHO-TEQ/L), 4.15 pg/L (0.016 pg-WHO-TEQ/L)였다. 먹는물의 다이옥신류 기여 농도는 일일섭취량 (tolerable daily intake (TDI), 4 pg-TEQ/kg/day)의 0.016%이었다. 정수처리에 의한 다이옥신류의 평균 TEQ 제거율은 88% 이상이었다. 그러나 112개의 샘플에서 2, 3, 7, 8-TeCDF (tetrachlorodibenzofuran)의 농도는 17% 증가하였다. 따라서, 2, 3, 7, 8-TeCDF의 농도에 영향을 미치는 공정을 파악하기 위하여 고도정수처리 및 일반정수처리에서의 제거율을 조사하였다. 다이옥신 동족체(congener)인 TeCDF와 non-ortho-PCB는 고도처리 및 표준정수처리에서 염소소독처리 후 TEQ 농도가 증가함을 보여, 먹는물 중 2, 3, 7, 8-TeCDF 농도는 염소소독처리에 의해 상승한 것으로 밝혀졌다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2004년도 학술대회지
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• pp.1-20
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• 2004

Polychlorinated biphenyls (PCBs), one a group of persistent and widespread environmental pollutants, have been considered to be involved in immunotoxicity, carcinogenesis, and apoptosis. However, the toxic effects and physical properties of a PCB congener are dependent on the structure. In the present study, we investigate the toxic effects and action mechanisms of PCBs In cells. Among the various congeners tested, 2,2',4,6,6'-PeCB-pentachlorobiphenyl (PeCB), a highly ortho-substituted congener having negligible binding affinity for aryl hydrocarbon receptor (AhR), caused the most potent toxicity and specific effects in several cell types. 2,2',4,6,6'-PeCB induced apoptotic cell death of human monocytic cells, suggesting that PCB-induced apoptosis may be linked to immunotoxicity. In addition, 2,2',4,6,6'-PeCB induced mitotic arrest by interfering with mitotic spindle assembly in NIH3T3 fibroblasts, followed by genetic instability which triggers p53 activation. Which suggests that 2,2',4,6,6'-PeCB may be involved in cancer development by causing genetic instability through mitotic spindle damage. On the other hand, 2,2',4,6,6'-PeCB increased cyclooxygenase-2 (COX-2) involved in cell survival through ERK1/2 MAPK and p53 in Rat-1 fibroblasts and mouse embryonic fibroblasts, triggering compensatory mechanism for abating its toxicity. Taken together, these results demonstrate that PCB congeners of different structure have distinct mechanism of action and 2,2',4,6,6'-PeCB causes several toxicity as well as compensatory mechanism in cells.

• 생명과학회지
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• 제20권7호
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• pp.1078-1085
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• 2010

PCDDs, PCDFs, dl-PCBs는 많은 역학 연구에서 독성오염물질이라고 간주되고 있는 생물축적 화학물질이다. 본 연구는 산모 초유 중에 이들 오염물질을 조사 분석하여 산모특성에 따른 축적성 및 상관성을 평가한 것으로, 실험대상 산모는 2007년에 평균연령 31.5세(표준편차=3.6세)의 건강한 초산부와 경산부이다. PCDDs 7개 이성질체, PCDFs 10개 이성질체, non-ortho PCBs 4개와 mono-ortho PCBs 8개 이성질체가 HRGC/HRMS로 분석되었다. 총 WHO-TEQs 평균값은 9.41 pg TEQ/g lipid로 다른 나라 농도에 비하여 낮은 수준이었다. 백분율의 증가와 함께 총 WHO-TEQs의 주요 기여자는 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD 및 3,3‘,4,4’,5-PCB (#126)이며, 총 WHO-TEQs의 60% 이상으로 나타났다. PCDFs 농도와 총 WHO-TEQs는 출산경험에 대해서는 음의 상관관계를 나타내었으며(p<0.05) 산모의 연령은 총 WHO-TEQs에 대해서 양의 상관관계를 나타내었다(p<0.01). 그러나, 임신 전 체질량지수와 어류섭취의 상관관계는 유의성이 없었다. 이들 결과로부터 출산경력과 산모 연령은 모유 내의 PCDD/DFs 및 dl-PCBs의 농도에 영향을 미치는 중요한 인자로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제38권6호
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• pp.568-578
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• 2010

본 연구에서는 다양한 목재부후균의 polychlorinated biphenyls (PCBs) 생분해 가능성을 구명하고자 7종의 백색부후균을 이용하여 PCB 혼합물 중 가장 분해가 어렵다고 알려진 Aroclor 1254와 1260을 대상으로 분해력이 우수한 목재부후균을 선발하였다. 그리고 선발된 목재부후균을 이용하여 GC 분석을 통해 Aroclor 1254, 1260의 분해율을 조사하였다. 고체배지 저항성 테스트를 통해 우수분해 균주로 선발된 Cystidodontia isubellina 는 다른 균주에 비해 균사생장량의 억제가 가장 적었으며 상대적으로 생장속도도 빠른 특징을 나타냈다. 선발된 C. isubellina에 의한 Aroclor 1254와 1260의 분해율 분석 결과, Aroclor 1254배양 13일째 57.57%로 가장 높은 분해율을 나타냈다. Aroclor 1260 역시 배양일수가 증가함에 따라 분해율 역시 증가하는 경향을 보였으며, 배양 13일째 49.43%로, 두 혼합물 모두 기존의 다른 연구에서보다 높은 분해율을 나타냈다.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.137-137
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• 2001

It is it well known fact that the most relevant toxic emissions such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-1ike polychlorinated biphenyls (PCBs) are produced from incinerators. Induction of cytochrome P450IA1 catalyzed 7-ethoxyresorufin 0-deethylase (EROD) activity in mammalian cell culture (EROD-microbioassay) is a selective and sensitive parameter used for the quantification of dioxin-like compounds. (omitted)

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제22권1호
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• pp.10-15
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• 2011

In this review, we have provided an overview of the environmental risk factors for attention deficit hyperactivity disorder (ADHD), focusing on the major environmental toxicants related to the disorder. Researchers have indicated that since the characteristics of ADHD are complex, the disorder’s etiology involves multiple genes of moderate effect interacting with environmental factors. The possible roles of prenatal and perinatal exposure have been the main focus of research on environmental risk factors for ADHD. Among environmental toxicants, we reviewed the potential effects on the development of ADHD of exposure to lead, nicotine, alcohol, polychlorinated biphenyls (PCBs), and dioxin. Further, for the each neurotoxicant, clinical prevention or intervention strategies aimed at reducing a child’s risk from environmental toxic insults have been presented.

• Korean Chemical Engineering Research
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• 제54권5호
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• pp.621-629
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• 2016

EU의 REACH 제도 도입에 따라 각종 화학물질에 대한 독성 및 활성 정보 확보를 위해 화학물질의 분자구조 정보를 기반으로 화학물질의 독성 및 활성을 예측하는 정량적구조활성관계(QSAR)에 대한 연구가 최근 활발히 진행되고 있다. QSAR 모델에 사용되는 분자표현자는 매우 다양하기 때문에 화학물질의 물성 및 활성을 잘 표현할 수 있는 주요한 분자표현자를 선택하는 과정은 QSAR 모델 개발에 있어 중요한 부분이다. 본 연구에서는 화학물질의 분자구조 정보를 나타내는 주요 분자표현자의 통계적 선택 방법과 부분최소자승법(Partial least square: PLS) 기반의 새로운 QSAR 모델을 제안하였다. 제안된 QSAR 모델은 130종의 폴리염화바이페닐(Polychlorinated biphenyl: PCB)에 대한 분배계수(log P)와 14종의 PCBs에 대한 반수 치사 농도(Lethal concentration 50%: $LC_{50}$) 예측에 사용되고, 제안된 QSAR 모델 예측 정확도는 기존의 OECD QSAR Toolbox에서 제공하는 QSAR 모델과 비교하였다. 관심 화학물질의 분자표현자와 활성정보 간의 높은 상관관계를 갖는 주요 분자표현자를 선별하기 위해서, 상관계수(r)와 variable importance on projections (VIP)기법을 적용하였으며, 화학물질의 독성 및 활성정보를 예측하기 위해 선별된 분자표현자와 활성정보를 이용해 부분최소자승법(PLS)를 사용하였다. 회귀계수($R^2$)와 prediction residual error sum of square (PRESS)을 이용한 성능평가결과, 제안된 QSAR 모델은 OECD QSAR Toolbox의 QSAR 모델보다 PCBs의 log P와 $LC_{50}$에 대하여 각각 26%, 91% 향상된 예측력을 나타내었다. 본 연구에서 제안된 계산독성학 기반의 QSAR 모델은 화학물질의 독성 및 활성정보에 대한 예측력을 향상시킬 수 있고 이러한 방법은 유독 화학물질의 인체 및 환경 위해성 평가에 기여할 것으로 판단된다.

• 한국습지학회지
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• 제9권1호
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• pp.79-89
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• 2007

This paper provides a comprehensive overview of the present status of several environmental problems caused by emerging toxic substances such as persistent organic pollutants (POPs), endocrine disrupting chemicals (EDCs), and arsenic in various environmental media in Vietnam. Monitoring data reported during the 1990s demonstrated elevated contamination of DDTs in most of these compartments in Vietnam. Studies in frame of the Asia-Pacific Mussel Watch Program revealed that fish, mussels and resident birds from Vietnam contained higher concentrations of DDTs as compared to other countries in region, suggesting the role of Vietnamese environment as a significant emission source of DDT in the Southeast Asian region. The estimated dietary intakes of PCBs and DDTs for Vietnamese were relatively high among Asian developing countries, suggesting potential risk for humans posed by thesechemicals. Widespread contamination of some endocrine active compounds such as alkylphenols and phthalates was observed at various sites along the coasts of northern and middle Vietnam. The presence of significant source of bisphenol-A along Red River estuary was revealed with the concentrations comparable to those reported for developed nations. A case study on seasonal variation of alkylphenols and phthalates in surface water of river delta and estuary of north and middle Vietnam indicated the differences in distribution of these compounds between dry and rainy seasons. Higher concentrations of alkylphenols and phthalates were found in dry season in estuary; while the contrasting pattern was observed in the river delta, showing elevated residues in rainy season. This result suggests the different behavior of alkylphenols and phthalates in river delta and coastal environment. From ecotoxicological perspectives, concentrations of bis-phenol A and di(2-ethylhexyl)phthalates [DEHP] in surface water from some locations in Vietnam exceeded the guideline values for Ecotoxicological Effects and the Environmental Risk Limit, respectively, suggesting potential for toxic implications on aquatic wildlife. Widespread and elevated arsenic contamination was discovered inour recent surveys in groundwater in a large area of suburban areas of Hanoi city, the capital of Vietnam. The most recent investigation in 4 villages showed about more than 50 % of groundwater samples contained As concentrations exceeding 50 g/L (the WHO and Vietnamese standard). In particular, in Son Dong villages, 58 % of samples analyzed contained As concentrations higher than 200 g/L. Good correlations were found in As concentrations in water and hair and urine of peoples in corresponding families, suggesting the chronic exposure to As by people living in As-contaminated ground water areas. In Son Dong village, As levels in hair (mean: 1.7 mg/kg dry wt) and urine (g/g creatinine) exceeding the reference values recommended by WHO, suggesting potential for human risk posed by long term accumulation of As in human body. Future studies should be focused on the time trends of POPs and EDCs in biota in Vietnam in order to predict future trend of contamination and to reveal new clues for understanding possible toxic impacts on aquatic organisms. The issues of arsenic contamination in groundwater and their chronic toxic implications on human health should be systematically investigated in the future.

• Toxicological Research
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• 제17권
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• pp.25-35
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• 2001

In 1990, Tolerable Daily Intake (TDI) of 10 pg TCDD/kg/day for dioxins based on carcinogenicity and reproductive toxicity was determined by WHO/EURO, that resulted in the establishment of TDIs in other countries. In Japan, Ministry of Health and Welfare and Environment Agency, respectively established the TDI of 10 pg TCDD/kg/day and Health Risk Assessment Index of 5 pg TCDD/kg/day in 1996. Accumulation of new scientific data, especially by molecular toxicology since 1990, resulted in the reevaluation of TDI by WHO-ECEH and IPCS in May, 1998. At this meeting, it was stressed that \circled1 toxic effects of dioxin is mediated through Ah-receptor in both animals and humans, \circled2 use of ebody burdeni concept is better than the use of traditional NOAEL/UF approach, \circled3 inclusion of coplanar PCBs in the TDI by the use of new WHO-TEF. LOAELs (0.16~200 ng TCDD/kg/day) obtained from reproductive toxicity and immunotoxicity in rats, and neurobehavioral toxicity and induction of endometriosis in rhesus monkeys are calculated to be the body burden of 10~50 ng TCDD/kg that is 14~37 pg TEQ/kg/day as human daily intake. Finally TDI of 1~4 pg TEQ/kg/day was established by applying the UF of 10. In Japan, reproductive toxicity and immunotoxicity in rats were used to obtain LOAELs (100~200 ng TCDD/kg/day). Finally TDI of 4 pg TEQ/kg/day was established in June 1999 by applying the UF of 10 to human daily intake of 43.6 pg TEQ/kg/day which corresponds to the body burden of 86 ng TCDD/kg.