• Analytical Science and Technology
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• v.13 no.6
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• pp.789-801
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• 2000

This analysis was conducted for PCDDs/PCDFs in sediment by isotope dilution HRGC/HRMS method. From the result, the mean recovery of surrogate standard was in the range of 70.1-80.8%. Among the distribution of 2, 3, 7, 8-substituted isomers, the concentration of OCDD represented almost 40.6-78.5% of total concentration and that of OCDF showed 6.6-14.7% and 1, 2, 3, 4, 6, 7, 8-HpCDD showed 5.1-7.7%. The portion of PCDDs represented 62.4-86.9% of total PCDDs/PCDFs. In the TEQ concentration 1, 2, 3, 4, 7, 8-PeCDF concentration represented 22.7-35.6 % of total TEQ concentration.

• Analytical Science and Technology
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• v.12 no.6
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• pp.550-557
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• 1999

This Analysis was conducted for 13 toxic-PCBs having TEF value among 209 PCBs isomers in sediment by isotope dilution HRGC/HRMS method. From the result, the recovery of surrogate standard was in the range of 71~99%. The concentration range for 13 toxic-PCBs in sediment was found to be 0.84~2.49 ng/g, among them the concentration levels of 2,2',3,3',4,4',5-HpCB(IUPAC No. 170) and 2,2',3,4,4',5,5'-HpCB(IUPAC No. 180) represented almost 50% of total concentrarion and that of 2,3,4,4,5-PeCB(IUPAC No. 114) showed over 10%. The TEQ concentration levelwas in the range of 0.38~2.63 pg-TEQ/g and 3,3',4,4',5-PeCB(IUPAC No. 126) concentration represented over 50% of total TEQ concentration.

• Analytical Science and Technology
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• v.16 no.4
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• pp.325-332
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• 2003

To analyze co-planar PCBs in food, the isotopic dilution method by high resolution gas chromatography/high resolution mass spectrometry was applied. Among 209 PCB congeners, 12 congeners (#77, #81, #126, #169, #105, #114, #118, #123, #156, #157, #167 and #189) were chosen as target compounds that were toxic congeners re-assessed by WHO in 1998. Milk and milk products including cheese and butter were collected as food samples. Samples were homogenized, spiked with the known amount of the standard mixture and extracted. After extraction, extracts were cleaned up by sulfuric acid impregnated silica gel, purified on silica gel and alumina column chromatography and then analyzed by HRGC/HRMS. As results, the overall recoveries were ranged from 83% to 106% and the limit of detection was about 0.1 pg/g at signal/noise>3. Levels of targets in the selected food samples were 0.001~0.107 pgWHO-TEQ/g.

• Analytical Science and Technology
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• v.18 no.3
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• pp.232-240
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• 2005

The total PCBs level in the transformer insulation oil samples using GC/ECD and HRGC/HRMS were ranged from 0.087 to $223.6{\mu}g/g$ and ranged from N.D. to $154.04{\mu}g/g$, respectively. The calculated TEQ values were ranged from 0.00067 to 6.8 ng WHO-TEQ/g. Among the samples, 6 samples showed higher than 2 ppm concentration (specific waste criterion of Korea). A variety in the concentration of total PCBs were observed between ECD and HRMS analysis. This is maybe due to quantification mehtod. The Aroclor 1248 wasn't present in the samples. The distribution pattern of Co-PCB congeners showed that the ratio of monoortho substituted congeners were higher than non-ortho substituted congeners. Among that, PCB-167 congener was predominant. In addition, the distribution of Co-PCBs congeners was different with that of flue gas and ambient air samples as well as commercial PCB formulations (Aroclor, Kanechlor).

• Analytical Science and Technology
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• v.14 no.1
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• pp.88-93
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• 2001

To measure the levels of dioxins in food selling at local markets, meat was analyzed by high resolution gas chromatography/high resolution ass spectrometry (HRGC/HRMS). The food samples were obtained from 5 large cities of Seoul, Chunchon, Daejon, Kwangju and Busan in Korea. All the samples were minced and extracted with Soxhlet extractor for 18 hours. After extraction, extracts were cleaned up by sulfuric acid impregnated silica gel, purified on a series of silica gel, alumina, carbon column chromatography and then analyzed by HRGC/HRMS. The contaminated levels were calculated as the TEQs by multiplying with the corresponding WHO-TEFs for each congeners. The overall recoveries were ranged from 80% to 153% and the limit of detection was about 0.01 ppt at S/N>3. The levels of PCDD/Fs for beef, pork and chicken were 0.018, 0.008 and <0.001 pgTEQ/g, respectively. In addition, the levels of non-ortho-co-planar PCBs for beef, pork and chicken were 0.008, 0.002 and 0.001 pgTEQ/g, respectively. Among food samples analyzed, chicken showed the lowest level of dioxin-like compounds. Regarding congener pattern, OCDD and PCB #77 were the highest contributing congeners.

• Journal of the Korean Chemical Society
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• v.38 no.11
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• pp.819-826
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• 1994

This study described a simple, rapid and cost effective analytical technique for the ultra-trace analysis of dioxins in environmental samples. Liquid-Liquid extraction methods were used for the initial extraction and enrichment of the analyte. Subsequent clean-up procedures were achieved by using strong cation exchanger, silica and Florisil cartridges. Extracts were analysed by HRGC/HRMS-SIM. The efficiency of these analytical methods was tested by recovery and selectivity for elimination of interferences such as phenols, pesticides and PCBs in each step. The mean recovery of 1,2,3,4-TCDD spiked at 10 ppt in sea water was about 92(${\pm}$1.6)%. This analytical method was applied to Kwangyang sea water and 4.5pg/L of 2,3,7,8-TCDD was determined.

• Analytical Science and Technology
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• v.16 no.4
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• pp.309-319
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• 2003

This study was performed to describe analysis method of 209 PCB congeners in ambient air samples. The samples were collected by high volume air sampler in Chonju city. Extracted samples were cleaned by silicagel cleanup modified with sulfuric acid and activated carbon cleanup processing. The cleaned samples were analyzed by high resolution gas chromatography and high resolution mass spectrometry (HRGC/HRMS) with DB-5 column (60 m, 0.25 mm i.d., 0.25 m film thickness) to analyze the 209 kinds of PCB congeners. PCBs levels of air samples were detected to the range between 0.003 and $0.163pg-TEQ/m^3$. The PCBs congener of 162 kinds were detected in samples analysed using DB-5 column and 37 kinds peaks were overlapped with congeners more than one. It is difficult to isolate PCB 118/106 and PCB 105/127 in coplanar PCB, so it is likely to overestimate the concentration.. The distribution of coplanar-PCB congeners in origin source samples (Kanechlor and exhaust gas from incinerator) was compared with that in air samples, and PCB 81, PCB 77, PCB 126, and PCB 169 were higher in incinerator samples.

• Analytical Science and Technology
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• v.17 no.2
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• pp.184-191
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• 2004

In this study, the separation of toxic dioxin 2,3,7,8-congeners by DB-5MS and SP-2331 GC columns which are widely used in HRGC/HRMS analysis was examined. Through the dioxin analysis of column performance check standard solution and fly ash sample, the isomer specific separation of 2,3,7,8-substituted dioxins from tetra to hexa-isomers on DB-5MS and SP-2331 columns were studied. The effect of I-TEQ value by these columns was also studied. The total concentrations of toxic dioxins for the column performance check standard solution were 508.4 ng/mL analyzed by DB-5MS and 515.8 ng/mL analyzed by SP-2331, respectively. The I-TEQ value obtained by both columns was shown to be almost equivalent for the column performance check standard solution and fly ash sample.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.96.1-96.1
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• 2008

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.95.1-95.1
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• 2008