• Environmental Analysis Health and Toxicology
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• v.11 no.3_4
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• pp.75-87
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• 1996

There are numerous and evidential findings that TCDD (2, 3, 7, 8-tetrachlorodibenzo-Pdioxin, or dioxin) is a potential carcinogen and general toxin in rodents. flowever, human risk assessment for dioxin exposure has been a topic of debate, owing in part to the large animal interspecies differences in its toxicity. We review dioxin-related reports indicating its toxicity, toxic effects in animal, and human epidemiologic findings. The intent of this paper does not provide a causal inference about chronic human diseases related to dioxin exposure. This summary would give a valuable clue for a researcher to conduct or design a further dioxin-related study.

• Analytical Science and Technology
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• v.23 no.4
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• pp.363-370
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• 2010

This study was performed to validate reference materials (RMs) for proficiency testing (PT) in waste inter-laboratories. Dioxin RMs were prepared from fly ash in industrial incinerators. The relative standard deviations (RSDs) of analytical results were 2.6~15.7% for the dioxin RMs in 10 replicates (between and withinbottles). Data were collected and statistical analysis was performed by the One-way ANOVA test. The combined uncertainties of target isomers in dioxin analysis were 0.114~7.091.

• Molecular & Cellular Toxicology
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• v.1 no.3
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• pp.164-171
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• 2005

Toxicological studies have an object of detecting adverse effects of a chemical on an organism based on observed toxicity marker (i.e., serum biochemical markers and chemical-specific gene expression) or phenotypic outcome. To date, most toxicogenomic studies concentrated on hepatic toxicity. cDNA microarray analysis enable discrimination of the responses in animals exposed to different classes of hepatotoxicants. In an effort to further characterize the mechanisms of 2, 3, 7, 8,-Tetrachlorodibenzo-p-dioxin (TCDD or dioxin)-mediated toxicity, comprehensive temporal-responsive microarray analyses were performed on hepatic tissue from Sprague-Dawley rats treated with TCDD. Hepatic gene expression profiles were monitored using custom DNA chip containing 490 cDNA clones related with toxicology. Gene expression analysis identified 26 features which exhibited a significant change. In this study, we observed that the genes related with oxidative stress in rats exposed to Dioxin, such as CYPIIA3 and glutathione S-transferase, were up-regulated at 24hr after exposure. In this study, we carried out to discover novel evidence for previously unknown gene expression patterns related to mechanism of hepatic toxicity in rats exposed to dioxin, and to elucidate the effects of dioxin on the gene expression after exposure to dioxin.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.78-86
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• 2005

Dioxins, especially 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD or dioxin), are ubiquitous environmental contaminants. TCDD is known that it has toxic effects in animals and humans, including chloracne, immune, reproductive and developmental toxicities, carcinogenicity, wasting syndrome and death. TCDD induces a broad spectrum of biological responses, including disruption of normal hormone signaling pathways, reproductive and developmental defects, immunotoxicity, liver damage, wasting syndrome and cancer. Many researches showed that TCDD induces gene expression of transcriptional factors related cell proliferation, signal transduction, immune system and cell cycle arrest at molecular and cellular levels. These toxic actions of TCDD are usually mediated with AhR (receptor, resulted from cell culture, animal and clinical studies). cDNA microarray can be used as a highly sensitive and informative marker for toxicity. Additionally, microarray analysis of dioxin-toxicity is able to provide an opportunity for the development of candidate bridging biomarkers of dioxin-toxicity. Through microarray technology, it is possible to understand the therapeutic effects of agonists within the context of toxic effects, classify new chemicals as to their complete effects on biological systems, and identify environmental factors that may influence safety.

• Molecular & Cellular Toxicology
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• v.2 no.1
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• pp.35-47
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• 2006

2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) are well known as the most toxic environmental compound in these days. Many researches are reported that dioxin produces multiple toxic effects, such as endocrine toxicity, reproductive toxicity, immunotoxicity and cancer. In this study, we carried to discover novel evidence for previously unknown gene expression patterns in human exposed to dioxin by using radioactive cDNA microarray. 548 workers who were divided into experimental and control groups according to their urinary Naphthol levels were enrolled in our study. Blood mRNA in human was isolated, and the gene expression profiles were analyzed by cDNA microarray. Gene expression analysis identified 52 genes which exhibited a significant change. In our study, most notably, genes involved in cell cycle, cell proliferation, signal transduction and apoptosis in human exposed to dioxin, such as CCND3, TSHR, and EFRN5, were up-regulated. In the current study, we observed gene expression of people that are exposed to dioxin using radioactive cDNA microarray. Through these results, we suggest when objects are exposed to toxic compounds, such as dioxin, the radioactive cDNA microarray may be using in sensitively detecting of cancerous change.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.1
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• pp.88-95
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• 2009

This study is for understanding the domestic possibilities of the high temperature incineration of waste containing Polychlorinated Biphenyls (PCBs) with the analysis of normal operation case and waste gas, fly ash, dioxin about bottom ash, Total-PCBs, Co-PCBs, and the for analysis the heavy metal leaching feature included by bottom ash and fly ash, heavy metal leaching experiment was implemented. The result shows the dioxin density of the waste gas from waste containing PCBs was $0.00699{\sim}0.00763ng-TEQ/Nm^3$, which is lower than $0.0192ng-TEQ/Nm^3$ from the normal operation case. And each Co-PCBs and total PCBs shows $0.00043{\sim}0.00112ng-TEQ/Nm^3$ and $3.06{\sim}3.87ng/m^3$ respectively. The bottom ash test result shows Dioxin 0.00225~0.00630ng-TEQ/g, Co-PCBs 0.00027~0.00082ng-TEQ/g, Total PCBs 0.9~2.6ng/g, and the fly ash shows Dioxin 0.00164~0.00344ng-TEQ/g, Co-PCBs 0.00053~0.00054ng-EQ/g, Total PCBs 0.64~0.84ng/g. The bottom ash and fly ash experiments for heavy metal leaching did not show any leaching but when it comes to the ingredients of the fly ash, Pb elements shows 31.01~237.7ppm, higher than leaching criterion. The analysis of the density of all air pollution material from the waste gas shows the lower value than permissible criterion.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.80-88
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• 2001

Objectives : In an epidemiologic study on the health impact of Agent Orange exposure, the valid estimation of exposure level is the most important step. Based on recent studies, we examined the correlation between exposure levels categorized by personal exposure estimates and serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD, Dioxin), exploring the possibility of utilizing the exposure level as a surrogate for the estimate of exposure to agent orange. Methods : During the study period (Jan 1996-Feb 1996), blood specimens of 745 subjects taken randomly among 1,329 persons and kept frozen, were analyzed for 2,3,7,8-TCDO and six other dioxin congeners. The serum dioxin and congeners were measured in 1998 by CDC, adjusted for serum lipids. We categorized the total exposure scores into five groups based on Agent Orange exposure data collected by interview and military records. Pearson and Spearman's correlation coefficients & multiple regression analysis were used to identify the relationship of the exposure level categorized with serum concentration of 2,3,7,8-TCDD, and six other dioxin congeners. Results : Dioxin and the other congeners, except 1,2,4,6,7,8-HpCDD, showed significant correlations to exposure categories (p<0.005): 2,3,7,8-TCDD and OCDD showed positive correlations, whereas the other congeners did negative. The values of 2,3,7,8-TCDD differed according to exposure category and proportionally increased from the low exposure group to the high, a dose-response relationship, even after other possible confounding variables were adjusted for. In multiple regression analysis, age$(\beta=0.033)$, dioxin$(\beta=0.433)$, 1,2,3,7,8-PeCDD$(\beta=-0.998)$, 1,2,3,4,7,8-HxCDD$(\beta=-0.773)$, 1,2,3,6,7,8-HxCDD$(\beta=0.255)$, 1,2,3,7,8,9-HxCDD$(\beta=-3.468)$, 1,2,3,4,6,7,8-HpCDD$(\beta=0.109)$ we re found to be significantly related to the total exposure score(p<0.005). Conclusion : This study demonstrated that the use of such categorizations as a surrogate measure of agent orange exposure in identifying exposure degrees in a health impact study is valid.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.11a
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• pp.143-143
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• 2004

• Environmental Analysis Health and Toxicology
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• v.29
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• pp.13.1-13.11
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• 2014

Objectives This study examined variations in the perceptions of dioxin risk among social groups defined by geographical living location, environmental education, and occupation. Dioxin risk perceptions were analyzed according to values, risk awareness, knowledge, and behavioral preferences. Methods A quasi-experimental survey was designed and conducted on individuals from seven experimental groups in Jeonju city, South Korea, including: people living near incineration facilities; people living far from incineration facilities; governmental experts; non-governmental organization members; office workers in developmental institutes or banks; students who were enrolled in environmental-related classes; and students who were enrolled in business-related classes. Results The results show variations among groups in values, awareness and behavioral preferences. Particular attention should be given to the result that groups with higher connectedness-to-nature values show higher willingness-to-act (WTA) for risk reduction. Result s can be summarized as follows. First, awareness is associated with one's geographical setting. Second, values and WTA behaviors are related to one's environmental-related education and occupation. Third, values are significantly related to WTA behaviors. Conclusions Different cultures, in terms of values or worldview, among groups influence their perceptions of dioxin risk and choices of risk reduction behaviors. It is important to consider values in communicating complicated long-term risk management involving public participation. Further research should be continuously conducted on the effects of multiple dimensions of values on one's WTA for risk reduction behaviors.

• Environmental Analysis Health and Toxicology
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• v.24 no.1
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• pp.33-41
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• 2009

Among the toxicants in the environment dioxin-like compounds, including TCDD(2,3,7,8-Tetrachlorodibenzo-p-Dioxin), are well known as carcinogen and teratogen. TCDD the most toxic of these compounds, may result in a wide variety of adverse health effects in humans and environment, including carconogenesis, hepatotoxicity, teratogenesis, and immunotoxicity. Also TCDD increases superoxide, peroxide radicals and induces oxidative stress that leads to breakage of DNA single-strand and mitochondrial dysfunction. Recently, there have been reports that persistent organic pollutants(POPs) may be causing metabolic disease through mitochondrial toxicity. In order to examine if dioxin brings about toxicity on mitochondria directly, we measured the change of the mitochondrial membrane potential after exposure to TCDD using JC-1 dye. After short time exposure of dioxin, mitochondrial depolarization was observed but it recovered to the control level immediately. This TCDD effect on mitochondrial membrane potential was not correlated either to the production of reactive oxygen species(ROS) or extracellular $Ca^{2+}$ by TCDD. Less than 2 hours exposure of TCDD did not show any change in ROS production but 0.25 nM TCDD for 48 hours or 0.5 nM TCDD for 12 hours exposure did increase in ROS production. Under these conditions of ROS production by TCDD, no changes in the mitochondrial membrane potential by TCDD was observed.