• Journal of the Korean Geotechnical Society
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• v.15 no.5
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• pp.241-257
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• 1999

Subsurface contamination of industrial hazardous organic substances is a serious social issue. Decomposing the hydrophobic organic compounds in the subsurface is technically difficult and the compounds can last as long-term contaminant sources of groundwater once they are sorbed on the soil. Although the danger of contaminated subsurface has long been recognized little was known about the effective remediation technique. Focusing on the remediation of the p-Cresol and 3, 5-Dichlorobiphenyl among subsurface contaminants, this paper studies the surfactant-enhanced desorption technique. Nonionic surfactant(Triton X-100) and anionic surfactant(SDS ) were used as desorbing solvents for extracting organic compound sorbed on soil particles. Sorption characteristics of soils and organic compounds were analyzed and the applications of surfactant solution were studied through batch tests and the flexible-wall permeameter tests. As a result of the sorption isotherm tests, a log-log linear relation was obtained between the linear-partition coefficient, $K_p$ and the octanol-water partition coefficient, $K_{ow}$ of each organic compound. The result of the batch test also showed that Triton X-100 at 0.5% of solution desorbs the 3, 5-Dichlorobiphenyl 28 times more than the water in the batch tests. The surfactant-enhanced subsurface remediation technique becomes more effective when the contaminants are hydrophobic and hard to be decomposed.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.255-263
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• 2012

Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants (BFRs), which are used in a variety of consumer products. Several of those are produced in large quantities. Their chemical structure similarities to polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs), as well as their toxicity, has been studied. PBDEs are persistent and lipophilic, which results in their bioaccumulation in the fatty tissues of organisms and enrichment throughout food chains. In addition, a number of studies also reported high levels of PBDEs in animals and food resulting from the use of contaminated animal feed Public concern about PBDEs levels in animals and food has been raised. Feed contamination by toxic chemicals has been the cause of the contamination of poultry products. The purpose of this study was to evaluate PBDEs in pig feed to search the origin chase of POPs in pigs. Feed samples were obtained wheat from East Europe, corn from South America and America, soybean meal from Korea, America, South America and India and tallow from Korea. The preparation of samples was based on the EPA method 1614. Instrumental analysis was based on the use of high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). Quantification was carried out by the isotopic dilution method. The analysis of ${\Sigma}PBDEs$ involved 22 PBDE congeners, including BDE-17, 28, 47, 49, 66, 71, 77, 85, 99, 100, 119, 126, 138, 153, 154, 156, 183, 184, 190, 191, 196 and 197.

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.253-261
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• 2012

Dioxin contamination on agroproducts is one of the most important issue in food safety. Herein, we measured concentration of 17 dioxins polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and 14 dioxin like-polychlorinated biphenyls (DL-PCBs) in the main grain (rice and barley) that were produced in Korea. The 36 rice samples were collected from rice processing complex at eight provinces, and the average concentrations of each province were ranged from 2.98 pg/g wet weight (w.w) to 4.98 pg/g w.w. as total PCDD/Fs and DL-PCBs. The seven barley samples were collected from Jeon-nam and Jeon-buk provinces, and their average total concentrations of PCDD/Fs and DL-PCBs were 3.00 pg/g w.w. and 3.24 pg/g w.w. respectively. The residual amounts and toxic equivalent (TEQ) of DL-PCBs in rice and barley were higher than PCDD/Fs. The average total TEQ of rice and barley were 0.0056 pg-TEQ/g and 0.0092 pg-TEQ/g on lower bound estimation respectively. Estimated daily intake of dioxins from rice and barley were calculated 1.03 pg-TEQ/day/person and 0.0534 pg-TEQ/day/person respectively. These were estimated 0.46% and 0.03% of Korean TDI based on 55 kg body weight.

• Analytical Science and Technology
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• v.22 no.5
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• pp.376-385
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• 2009

In our study, the accuracy for measurement of seventeen 2,3,7,8-substituted PCDDs/PCDFs in certified reference material (CRM) which is the sample of homogeneous sediment matrix taken from an area known to have significant chemical contamination, particularly PCBs (polychlorinated biphenyls), was evaluated. Though the methodology in this study followed the official method of unintentionally produced persistent organic pollutants (UPOPs) announced by the Ministry of Environment of the Republic of Korea in 2007, there were slight changes using additional purification step by activated carbon column because the interferences of sample were not sufficiently removed when only multi-silica column and alumina column have been used for purification. The |En| number proposed by the Korea Research Institute of Standards and Science was used for a valuation basis of the accuracy. The |En| numbers of seventeen 2,3,7,8-substituted PCDDs/PCDFs have been indicated as 1 and below, they were decided "Pass" in this test, when DB-5MS column and SP-2331 column were used together. Because 1,2,3,7,8-PeCDD and #169-HxCB were not separated on DB-5MS column, the ions of 1,2,3,7,8-PeCDD were selected at M/M+2 instead of M+2/M+4 suggested by EPA 1613. It is possible to distinguish them in HRGC/HRMS analysis.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.39-49
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• 1996

Hundreds of contaminated sites have been generated due to the past mismagement of toxic substances, the lack of adequate environmental controls and ignorance of the potential environmental impacts of general activities in Canada. The general public, industry and governments have been addressing the contaminated sites with a number of cleanup responses. Environmental protection and remediation have become top priorities for the public and private sectors alike in Canada. Between the late 1980s and the early 1990s, the Canadian Environmental Protection Act and Canada's Green Plan were followed by provincial and territorial laws and policies to regulate contaminated sites. The National Contaminated Site Remediation Program(NCSRP) was initiated in 1989. It has been administered through bilateral agreements between the federal and participating provincial/territorial governments. They have committed a total of $250 million toward orphan site cleanup and technology development/demonstration over a five year period. The federal government has committed an additional $25 million to assess contaminated sites on federal crown land. Over 40 orphan high-risk contaminated sites, over 230 federal sites and over 35 technology development/demonstration projects have been addressed. The Canadian Council of Ministers of the Environment has developed a series of guidance documents to ensure a consistent and successful implementation of the Program. The management/regulation scheme of contaminated sites generally consists of： 1) identifying and investigating sites, 2) determining site contamination, 3) recognizing responsibility and liability, 4) assessing priority for remediation, 5) activation, evaluation and implementing remediation options, and 6) documenting remediation completion. The NCSRP supported the successful development/demonstration of a wide range of innovative remedial technologies. They are related to stabilization/solidification, thermal washing/flushing, advanced oxidation, sonics, and groundwater contaminated with hydrocarbons, PAHS, PCBs, heavy metals, and other hazardous pollutants in a variety of site environments.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.185-192
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• 1999

To assess the soil quality of Chonan City, soil analyses were conducted according to the 14 different sampling sites. The soil pH of the agricultural area near the expressway was lower than that of the other farming area, which indicated that this acidification was probably attributed to the acid rain caused by the traffic exhaust gas such as SOx and NOx. Acidification was more severe in the dry farming area than in the rice paddy area. All concentration of 6 different heavy metals (As, Cu, Cd, $Cr^{6+}$, Hg, Pb) and organic contaminants (cyanide, organic-p, PCBs, phenols) were found to be lower than the standard of soil pollution. The concentration of BTEX also lower than the standard of soil pollution. An assessment using the SPI (Soil Pollution Index). which was developed to estimate an overall soil quality, was performed. Each SPC (Soil Pollution Score) were evaluated with the results of the data from this study. The soil quality of most area of Chonan City was determined to Class 1 , which indicated that the soil was healthy.

• Ocean and Polar Research
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• v.38 no.3
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• pp.171-184
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• 2016

In order to assess the level of contamination and identify the priority contaminants in the Busan coast, intensive sediment sampling was conducted and persistent organic pollutants and heavy metals were analyzed. The Sediment Quality Index (SQI) was derived based on the contaminant data by comparing with Sediment Quality Guidelines (SQGs) established in Korea, Canada, and Australia/New Zealand. Toxic contaminants were found to be widely distributed across the coast. Among organic contaminants, PAHs showed the highest concentration, followed by butyltins, nonylphenols, PBDEs, DDTs, PCBs, HCHs and CHLs. Heavy metals were also abundantly detected with the highest concentration of Zn followed by Cu > Cr > Pb > Ni > As > Cd > Hg. Compared to organic contaminants, most heavy metals, except for Cu and Hg, were homogeneously distributed along the coast in a good relationship with total organic carbon of sediment particles. In general, the concentrations of organic compounds and heavy metals were highest at the inner part of harbor areas with a tendency to decline from inside areas to the outside, indicating the high loading of pollutants from harbors. A high exceedance for low-SQGs and high-SQGs was found for TBT, p'-DDT, p,p'-DDD, Cu and Zn. The SQI scores calculated from low-SQGs and high-SQGs were in the range of 18-100 and 54-100, respectively. The inner part of Busan Harbor, Dadaepo Harbor, and Gamcheon Harbor were observed as being regions of concern. Overall, TBT, Cu, and p,p'-DDT were the chemicals most frequently exceeding SQGs and influencing SQI scores.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.6-12
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• 2005

Contamination of soils and groundwater by leakage of petroleum compounds from underground storage tanks (USTs) has become great environmental issues. Conventional methods such as soil vapor extraction (SVE) used for the remediation of unsaturated soils contaminated with volatile organic compounds might not be applied for the removal of semi-volatile organic compounds such as diesel fuels and PCBs, which have low volatility and high hydrophobicity. The objective of this study is to develop a hot air injection method to remove semi-volatile compounds. Additionally, operation parameters such as temperature, air flow rate, and water content are evaluated. Experimental results show that diesel ranged organics (DROs) are removed in the order of volatility of organic compounds. As expected, removal efficiency of organics is highly dependent on the temperature. It is considered that more than $90\%$ of organic contaminants whose carbon numbers range between 17 and 22 can be removed efficiently by the hot air injection-extraction method (modified SVE) over the $100^{\circ}C$. It is also found that increased air flow rate resulted in high removal rate of contaminants. However, air flow rate over 40 cc/min is not effective for the operation aspects, due to mass transfer limitation on the volatilization rate of the contaminants. The effect of the water content on the decane removal is minimal, but some components show large dependence on the removal efficiency with increasing water content.

• Analytical Science and Technology
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• v.15 no.3
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• pp.270-286
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• 2002

The human adipose and milk samples analyzed in this study were collected at hospitals in Seoul, Masan and Jinju. The mean values of International Dioxin Toxic Equivalents (I-TEQ) of PCDDs and PCDFs in human adipose samples from the three regions were calculated as 9 pg I-TEQ/g(0.2 ~ 30 pg TEQ/g, lipid weight basis) and 8 pg I-TEQ/g (0.8 ~ 25 pg TEQ/g), respectively. The residue levels of PCDDs-TEQ and PCDFs-TEQ in human milk collected from Masan were 13 pg I-TEQ/g (lipid wt.) and 4.8 pg I-TEQ/g, respectively. On the whole, the contamination levels of these compounds in the Korean population were lower than those in the other countries. Based on the analytical data and assuming a daily intake consumption of 800 mL milk with 3% fat, the average daily intake of PCDDs/DFs via human milk for a baby weighing 5 Kg could be calculated. The daily intake of PCDDs/DFs via breast-feeding was estimated to be 39 pg/kg body weight/day for 2,3,7,8-TeCDD and 86 pg/kg/day for TEQ. These levels are far above all virtually safe dose(VSD) or tolerable daily intake(TDI) values proposed by health authorities in various countries, ranging from 0.001(US EPA) to 4 pg/kag/day (WHO).

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.2
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• pp.102-107
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• 2007

Environmental contamination becomes a great public concern as our society gets industrialized rapidly. The present study examine the role of chitosan in a effort to intervene the environmental pollutant-induced toxicity. PCB-induced neurotoxicity with respect to the PKC signaling was examined. Since the developing neuron is particularly sensitive to PCB-induced neurotoxicity, we isolated cerebellar granule cells derived from 7-day old SD rats and grew cells in culture for additional 7 days to mimic PND-14 conditions. PCB showed the alteration of PKC signaling pathway. The alteration was structure-dependent. Mono-ortho-substituted congeners at a high dose showed a significant increase of total PKC activity at [$^3H$]PDBu binding assay, indicating that mono-ortho-substituted congeners are more neuroactive than non-ortho-substituted congeners in neuronal cells. PKC isoforms were immunoblotted with respective monoclonal antibodies. PKC-beta II and -epsilon were activated with mono-ortho-substituted congeners exposure. The result suggests that the position with ortho has a higher potential of altering the signaling pathway. Alteration of PKC was blocked with treatment of high molecular weight of chitosan. The study demonstrated that the ortho position in PCBs are important in assessing the structure-activity relationship. The results suggest a potential use of marine bioactive materials as a means of nutritional intervention to prevent the harmful effects of pollutant-derived toxicity.