• Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.241-250
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• 2012

Polycyclic aromatic hydrocarbons (PAHs), butyltins (BTs), nonylphenol (NP), and fecal sterols concentrations in sediments were investigated from Gunsan coast of Korea to evaluate organic pollution from anthropogenic activities. Sediment toxicity was also examined by bacterial bioluminescence toxicity test (Vibrio fischeri). The concentrations of 16 PAHs in sediments ranged from 67.9 to 425 ng/g dry wt; BTs ranged from 2.79 to 14.1 ng Sn/g dry wt; NP ranged from 20.7 to 2171 ng/g dry wt; and coprostanol, a fecal sterol, ranged from 7.60 to 245 ng/g dry wt. Effective concentration 50% ($EC_{50}$) of sediments ranged from 0.38 to 23.8 mg/mL. Most of the chemicals were present at levels lower than or comparable to the previously reported values from Korea. However, NP levels in the present study were in the high range of levels reported from the Korean coast, and 40% of the measured samples exceeded screening and ecotoxicological values of NP suggested by the Netherlands and Canada. This suggests that an ongoing source of NP is a serious concern in the Gunsan coast. High levels of contaminants were found in the proximity of potential sources, such as the outfall of a wastewater treatment plant for NP, an anthracite-fired power plant for PAHs, and ports for BTs, fecal sterols, and sediment toxicity. This indicates that Gunsan coast has various potential sources of marine sediment contaminants.

• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.62-71
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• 2008

Soil quality standards (SQS) are necessary to protect the human health and soil biota from the exposure to soil pollutants. The current SQS in Korea contain only sixteen substances, and it is scheduled to expand the number of substances. Chemical ranking and scoring (CRS) system is very effective to screen the priority chemicals for the future SQS in terms of their toxicity and exposure potential. In this study, several CRS systems were extensively compared to propose the assessment factors that required for the screening of soil pollutants The CRS systems considered in this study include the CHEMS-1 (Chemical Hazard Evaluation for Management Strategies), SCRAM (Scoring and Ranking Assessment Model), EURAM (European Union Risk Ranking Method), ARET (Accelerated Reduction/Elimination of Toxics), CRSKorea, and other systems. The additional assessment factors of CRS suitable for soil pollutants were suggested. We suggest soil adsorption factor as an appropriate factor of CRS system to consider chemical transport from soil to groundwater. Other factors such as soil emission rate and cases of accident of soil pollutants were included. These results were reflected to screen the priority chemicals in Korea, as a part of the project entitled ‘Setting the Priority of Soil Contaminants'.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.45-53
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• 2009

A quick and simple detection method of explosive compounds in environmental matrix (soil and water) can provide a screening step which reduces the number of unnecessary samples and the cost of expensive laboratory analysis at a site investigation. A commercially available EXPRAY$^{(R)}$Explosives Field Detection Kit (EXPRAY) was used to determine the minimum detection concentration and to test the possibility of semi-quantitative analysis of 14 explosive compounds using standard solutions. The results showed that EXPRAY could detect 5 explosive compounds, TNT, RDX, HMX, Tetryl, and TNB, out of 14 US EPA designated explosives. The minimum detection limit of the nitramine explosives was 14 ng/$^2$ for HMX and RDX. EXPRAY was more sensitive to nitroaromatics than the nitramines and the minimum detection limits per unit area (mm$^2$) for Tetryl, TNB, and TNT, were 3 ng, 3 ng, and 0.3 ng, respectively. The semi-quantification of 5 explosive compounds in an order ofmagnitude could be achieved by the intensity of developed color only when EXPRAY was applied on the standard solutions under controlled laboratory conditions. With contaminated soil samples, however, only the presence and type of explosive compounds was identified. Therefore, EXPRAY is an economic and sensitive method that can be used in a screening step for the identification of explosives in the field samples.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.61-73
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• 2003

A model describing the distribution of contaminants in soil/water systems for the application of soil-washing technology using surfactant was developed. The model simulation was conducted for screening the best surfactant, evaluating the effect of water dose, and optimizing soil-washing methodology. Naphthalene, phenanthrene, and pyrene as target compounds and Triton X-l00, Tergitol NP-10, Igepal CA-720, and Brij 30 as surfactants were used in the model simulations. The washing efficiency was not greatly enhanced by increasing water dose with the same total surfactant dose. The approach of successive washings was more efficient than a single washing with the same amount of water and surfactant. Equal allotment of the amount of water and surfactant was the best condition for the successive washings. The model can be applied for the optimal design of the soil washing process without extra experimental efforts.

• Journal of Wetlands Research
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• v.12 no.1
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• pp.23-31
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• 2010

Chlorinated aliphatic hydrocarbons (CAHs) such as tetrachloroethylene (PCE), 1,1,1-trichloroethane (1,1,1-TCA) are the contaminants most frequently found in soil and groundwater. They have a potential to be toxic to and persistent in environment. This study is focused on selection of zero-valent metal and ores for the removal of high concentration PCE or 1,1,1-TCA and mixture of two compound. For the screening of suitable metals, we measured dechlorination rate, removal capacities and economics by using batch reactor test. This results suggest that removal rate and dechlorination of high quality iron and zinc are higher than slag and nature ores like zinc and manganese. Among nature ores, zinc ores(64% purity) have highest removal capacities. And in economics zinc ores is 10 times better than high quality metal tested. We conclude zinc ore is most suitable metal for the removal of PCE or 1,1,1-TCA.

• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.333-341
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• 2005

In order to know whether polychaetes could be used as an appropriate organism for the detection of genotoxicity, DNA strand breaks were evaluated in blood cells of a nereidae worm (Perinereis aibuhitensis) exposed to various aquatic chemical pollutants (e.g. Cd, Pb, Pyrene, Benaor[a]pyrene). Hydrogen peroxide increased DNA strand breaks up to the highest concentration (10 $\mu$M). Higher concentration than 0.1 $\mu$M showed a significantly more DNA damage than control. Cadmium and lead also showed higher DNA damage than control, over 1.0 and 1 $\mu$g/L, respectively. In case of pyrene, DNA damage was detected even at 0.001 $\mu$g/L. However, DNA damage decreased due to apoptosis at the highest concentration of pyrene and Pb. This study suggested that the polythaetous blood cells could be used effectively for screening genotoxic contaminants in the environment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.2 s.110
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• pp.21-29
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• 2005

Increase in the utilization rate of recycled paper has significantly increased the problem associated with stickies. Despite the effort to eliminate contaminants from recycled furnishes, stickies are still the most serious obstacle in using recycled paper. The amount of micro stickies that are too small to be eliminated by screening, tends to increase significantly as the closure level of white water system is increased and the quality of raw material deteriorates. To establish a process efficient in removing micro stickies is strongly required. In this study, the surface characteristic of micro stickies was investigated with contact angle measurement. Surface energies of MCC, PSA film and model micro stickies were 53.37 mN/m, 29.75mN/m, and 29.63mN/m, respectively. This indicates that the surface characteristic of MMS is very similar to PSA. Thus, solvent coating of PSA and evaporation of the solvent provided excellent model micro stickies for flotation experiment.

• Mass Spectrometry Letters
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• v.3 no.3
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• pp.78-81
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• 2012

The hydrophobic hydrocarbon chain and the polar sulfate group confer surfactant properties and enable them to be used as anionic surfactants. Anionic surfactants (AS) are known for their adverse impact on environment, particularly on aquatic ecosystem. In the present study a fast, sensitive and selective method for the determination and subsequent quantification of six anionic surfactants was developed using hydrophilic interactive liquid chromatography (HILIC) coupled to a electrospray ionization (ESI) mass spectrometer (MS), in the concentration range 15-20 ${\mu}g/L$. The capability of the method was established using regression analysis and ANOVA. The method performance was evaluated by analyzing real time surface water spiked with 1-dodecyl hydrogen sulfate at 15 ${\mu}g/L$. Combined efficiency of solid phase extraction and MS detection established recovery of 89% in presence of natural matrix. These results point out that HILIC coupled to multistage MS procedures can be a powerful technique for environmental applications concerning the screening of polar contaminants.

• Journal of Aquaculture
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• v.16 no.3
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.06a
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• pp.34-39
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• 2000

Today's size of production operations in the packaging paper sector I sconstantly increasing , featuring integral processing systems, high-speed paper machines, and the increased marketing of lower basis weight products. The risk factors involved in these large investments lie more than ever in the available furnish potential and ongoing requirements for further closure of water loops and lower operating costs. A comparison is drawn between recovered paper furnish mixtures used in European mills with regard to fibre properties, strength potential and contaminant content, Both the furnish situation and development trends in modern fluting and testliner machines are instigating concept changes in stock preparation, the approach flow as well as in process water and rejects technology. Developments are currently focussed for example on more efficient debris separation using fine slotted screening, optimized refining , more systematic process water management with loop separation and integral water clarification as well as more efficient removal of microstickies, fillers and fines through appropriate combination of rejects handling and water clarification processes. Product quality differentiation depends decisively on strength characteristics as a function of refining , fines removal , paper machine technology, and sizing . Maximum availability of today's high speed paper machines and , as a result, cost effective production can be ensured by optimum balancing of all subsystems with in the overall concept and by reliable control of problems with contaminants and deposits.