• 대한화학회지
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• 제38권11호
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• pp.819-826
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• 1994

환경시료중 수질시료속에 미량으로 존재하는 다이옥신류를 정량하기 위한 분석법의 연구로써 시료의 유형에 관계없이 적용시킬 수 있는 보다 간단하고 효유적인 전처리 방법을 조사하고 HRGC/HRMS-SIM 방법으로 검출한계를 낮추며 정성과 정량이 동시에 이루어지도록 하였다. 초기농축단계로 dichloromethane(DCM)을 이용한 액체-액체추출법을, 정제단계로 강양이온교환수지, 실리카 직렬 카트리지컬럼, Flotisil 카트리지컬럼을 이용한 고체상 추출법을 사용하였다. 각각의 회수율과 방해물제거에 대한 선택성으로부터 본 분석법의 효율성을 조사했으며 TCDD의 손실없이 페놀류, 농약류, PCB류를 제거, 분리할 수 있었다. 해수 1L에 1,2,3,4-TCDD 10ng을 첨가시킨 다음 농축 및 정제의 모든 단계를 거친 후 평균회수율은 92(${\pm}$1.6)%였다. 또한 광양만에서 채취한 해수시료에 대해 분 분석법을 적용시킨 결과 4.5(${\pm}$1.1)pg/L의 2,3,7,8-TCDD를 검출할 수 있었다.

• 분석과학
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• 제24권6호
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• pp.484-492
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• 2011

우리나라 주요 하천수계의 대표적인 지점 한 곳씩 선정하여 이곳에 서식하는 붕어에 대한 PCDDs, PCDFs 및 DL-PCBs의 체내 축적 정도를 분석하고 분포특성을 살펴보았다. 회수율은 PCDDs 및 PCDFs는 50.6%~88.3%, DL-PCBs는 52.3%~93.2%이었으며, 붕어 체내에 축적된 PCDDs, PCDFs 및 DL-PCBs를 모두 합한 ${\sum}$dioxins은 평균 0.39 pg TEQ $g^{-1}$ wet wt., 중앙값 0.14 pg TEQ/g wet wt., 그리고 농도 범위는 0.047-1.0 pg TEQ/g wet wt.으로 나타났다. PCDDs 및 PCDFs는 일부 시료에서 검출된 반면, DL-PCBs는모든 시료에서 검출되었으며 ${\sum}$dioxins에 대한 기여도가 83.6%로서 가장 높았다. 다음으로 PCDFs와 PCDDs가 각각 ${\sum}$dioxins의 12.7%와 3.7%를 기여하고 있었다.

• 대한수의학회지
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• 제48권1호
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• pp.39-48
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• 2008

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are ubiquitous and can contaminate the food chain. A study monitoring PCDD/Fs in imported meat was conducted at the National Veterinary Research and Quarantine Service (NVRQS, Republic of Korea) in order to maintain food safety from the bioaccumulative PCDD/Fs. Seventeen PCDD/Fs with toxic equivalency factors (TEFs) established by World Health Organization (WHO, 1998) were analyzed in imported beef, pork, and chicken by high resolution gas chromatography/mass spectrometry (HR-GC/MS). Results of the monitoring for the last 5 years are presented. The levels of PCDD/Fs were similar to other studies except two unusually high concentrations in pork and beef. Excessive levels greater than the Korean provisional maximum residue limit of PCDD/Fs were found in a sample of pork imported from Chile and a sample of beef imported from U.S, and those products were rejected and returned. There was no obvious trend or differences with respect to time or origin of meat in this study.

• Environmental Engineering Research
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• 제17권3호
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• pp.157-165
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• 2012

This experimental study was performed to obtain thermal energy from the combustion of synthetic gas, produced by the pyrolysis of insulating oil containing polychlorinated biphenyls (PCBs) in a high temperature and high pressure reactor. The average synthetic gas generated was $59.67Am^3/hr$ via the steady state gasification of insulating oil waste (20 kg/hr) with average concentrations (standard deviation) of $CO_2$, CO, and $H_2$ in the synthetic gas of $38.63{\pm}3.11%$, $35.18{\pm}1.93%$, and $28.42{\pm}1.68%$, respectively. The concentrations of the PCBs in the transformer insulating oil and synthetic gas after its gasification, and the concentrations of the dioxins that could be produced from the incomplete degradation of PCBs were measured. It was revealed that the PCBs in the insulating oil were composed of the series from tetrachlorobiphenyl to octachlorobiphenyl. However, only the #49, #44, #52, and #47/75/48 congeners were detected from the synthetic gas after gasification of the insulating oil and in the flue gas from the combustor. In conclusion, the experimental conditions suggested in this study were very useful for the appropriate treatment of insulating oil containing PCBs. Also, fuel gas containing CO and $H_2$ can be obtained from the pyrolysis of insulating oil containing PCBs.

• 분석과학
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• 제12권1호
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• pp.61-67
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• 1999

도시쓰레기 소각로의 배출가스 중 다이옥신(Dioxins, PCDDs/PCDFs), chlorobenzenes(CBs) 및 chlorophenols(CPs)를 측정 분석하고, 각 시설에 대한 다이옥신 및 전구물질의 배출 패턴을 조사하였다. 대형쓰레기 소각로의 배출가스 중 다이옥신류의 농도를 독성등가환산(Toxic Equivalent, TEQ) 농도로 평가한 결과 오염화퓨란류(Pentachlorofurans, PeCDFs), 육염화퓨란류(Hepxachlorofurans, HxCDFs) 및 칠염화퓨란류(Heptachlorofurans, HeCDFs)가 전체의 76.24%, 60.84%를 차지하는 것으로 나타났으며, chlorophenols은 2,4,6-trichlorophenol(TCP), 2,3,4,6-tetrachlorophenol(TeCP) 및 pentachlorophenol(PeCP)이, chlorobenzens은 1,2,4,5-tetrachlorobenzene(TeCB) 및 hexachlorobenzene(HxCB)의 형태로 주로 배출되는 것으로 나타났다.

• Fisheries and Aquatic Sciences
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• 제10권2호
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• pp.93-101
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• 2007

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in marine sediments from Mokpo coastal water of Korea. Total and toxic equivalent (TEQ) concentrations of PCDD/Fs ranged from 19.4 to 175pg/g dry weight and ranged from 0.195 to 2.87 pg WHO-TEQ/g dry weight, respectively. These PCDD/F concentrations were below the safety sediment value (20 pg TEQ/g dry weight) of chronic toxicity. A highly significant correlation between the concentrations of PCDD/Fs and total organic carbon (TOC) in marine sediments was observed. Overall PCDD/F concentrations in the sediments were elevated in rivers and at inner locations close to harbors, indicating that these contaminants derived from local discharges of human activities. PCDD/F concentrations measured in our study were lower than those in several industrialized areas in Korea. Nonparametric multidimensional scaling (MDS) ordination showed that combustion processes from industrial complexes are the major source of PCDD/Fs in Mokpo coastal water.

• 분석과학
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• 제17권2호
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• pp.184-191
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• 2004

본 연구에서는 HRGC/HRMS에 의한 다이옥신분석에 있어 가장 널리 사용되고 있는 SP-2331 및 DB-5MS 컬럼에 의한 독성 2,3,7,8-다이옥신 동족체 분리의 영향에 대하여 조사하였다. 컬럼분리성능평가 표준용액과 비산재 시료의 분석을 통하여 이들 컬럼에 의한 tetra, penta 및 hexa-2,3,7,8-동족체의 분리에 대한 부분과 I-TEQ값의 영향을 중심으로 설명하였다. 이들 두 컬럼에 의한 분석에서 컬럼분리성능평가 표준용액의 경우 DB-5MS에 의해서는 총 2,3,7,8-치환이성체의 농도는 508.4 ng/mL로 나타났으며, SP-2331에 의해서는 515.8 ng/mL로 나타났다. 이들을 I-TEQ값으로 환산하였을 때 거의 동등하게 나타났다. 비산재 시료의 경우에서도 이들 두 컬럼에 의한 2,3,7,8-치환이성체의 총 농도와 I-TEQ값이 거의 비슷하게 나타났다.

• The Korean Journal of Physiology and Pharmacology
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• 제10권6호
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• pp.349-354
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• 2006

The aromatic hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates many of the biological and toxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related chemicals. The application of recombinant reporter plasmid such as the firefly luciferase gene has proven to be a very effective method to detect these chemicals. The bioassay system, CALUX, is sensitive in directly detecting AhR-agonists from a variety of environmental and biologic materials. However, responses of the AhR-dependent bioassays are dependent on the cell types used. Thus, we developed a sensitive bioassay using the recombinant mouse hepatoma cell (Hepa1c1c7) for the determination of dioxins. The recombinant cell line was stably transfected with firefly luciferase reporter gene (pGudLuc1.1). The transfected cells showed the highest induction of luciferase activity at 4.5 hr and a decrease beyond this time point. The system showed the highest sensitivity of detection ever reported. Upon TCDD exposure cells showed 2 fold increase at 10 pM and 7 fold increase at 100 pM, respectively. The passage number after the transfection played an important role in the sensitivity. The increase of passage number tended to increase the sensitivity of the cells up to 15. The media without phenol red showed a higher induction rate than with phenol red, suggesting the preferable use of phenol red-free media for the bioassay. Since each of the assays has unique characteristics that make them suitable for some screening applications and not others, development of sensitive bioanalytical methods based on a variety of cellular systems in a key to the successful determination of dioxins. The bioassay system developed in this study will contribute to further development of successful screening the AhR agonists among the environmental mixture. In addition, the rapid and sensitive nature of this cellular system can be applied as a valuable tool to screen the dioxin-like moieties among the prodrugs at the initial stage, thereby expediting the new drug discovery.

• 한국토양비료학회지
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• 제44권4호
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• pp.662-666
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• 2011

In this study, distribution characteristics of dioxins in soils in Busan, Korea were investigated regarding different land use types. Soil sampling sites that distributed through the Busan city showed dioxin concentration ranging from 0.489 to $322.736pg-TEQ\;g^{-1}$ dry weight with a mean value of $26.257pg-TEQ\;g^{-1}$ dry weight. The mean dioxin concentrations of investigated soils ranged from 1.554 to $50.357pg-TEQ\;g^{-1}$ dry weight in consideration of each land use type. That in metal refinery sites with $50.357pg-TEQ\;g^{-1}$ dry weight was higher than any other sites, followed by waste incinerator sites with $44.285pg-TEQ\;g^{-1}$ dry weight. The majority of soil samples had the same dioxin congener profiling despite the different range of dioxin concentration. Octa-CDD was the major contributor among seventeen dioxin congeners with the range from 29.5 to 70.1% in real values. In contrast to real values, dioxin congener profiles in TEQ values were dominated by 2,3,4,7,8-PeCDF which contributed about 35.3~43.8% to the total dioxin concentrations. It was judged by these results that penta-CDF was the major contributor of soil samples in Busan city. The mean ratio of PCDFs/PCDDs in real values was about 0.71, but that in TEQ values was, in contrast to it, approximately 3.03.

• Bulletin of the Korean Chemical Society
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• 제20권6호
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• pp.689-695
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• 1999

Supercritical fluid extraction (SFE), ultrasonic extraction (USE), and accelerated solvent extraction (ASE) were compared with the well known Soxhlet extraction for the extraction of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins(PCDDs) from the XAD-2 resin which was used to adsorb PCDDs in the atmosphere. XAD-2 resin spiked with five PCDDs was chosen as a sample. The optimum conditions for the extraction of PCDDs by SFE were turned out to be the use of CO2 modified with 10% toluene at 100 ℃ and 350 atm, with 5 min static extraction followed by 20 min dynamic extraction. SFE gave a good extraction rate with good reproducibility for PCDDs ranging from 68 to 98%. The ultrasonic extraction of PCDDs from XAD-2 was investigated and compared with other extractions. A probe type method was compared with a bath type. Two extraction solvents, toluene and acetone were compared with their mixture. The use of their mixture in probe type, with 9 minutes of extraction time, was found to be the optimum condition. The average recovery of the five PCDDs for USE was 82-93%. Accelerated solvent extraction (ASE) with a liquid solvent, a new technique for sample preparation, was performed under elevated temperatures and pressures. The effect of tem-perature on the efficiency of ASE was investigated. The extraction time for a 10 g sample was less than 15 min, when the organic solvent was n-hexaneacetone mixture (1 : 1, v/v). Using ASE, the average recoveries of five PCDDs ranged from 90 to 103%. SFE, USE, and ASE were faster and less laborious than Soxhlet extraction. The former three methods required less solvent than Soxhlet extraction. SFE required no concentration of the solvent extracts. SFE and ASE failed to perform simultaneous parallel extractions because of instrumental limitations.