• Economic and Environmental Geology
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• v.36 no.4
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• pp.275-284
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• 2003

We collected the samples of stream sediments from primary channels in order to establish natural background of major and minor elements for geologic units in the Gurye area. Stream sediments samples having no possibility of contamination effect and representing drainage basins composed of uniform geology, were collected from April to May in 1999, the chemical analysis of which was carried out. The tolerable level was used to investigate the enrichment degree of harmful elements. The contents of Ni and Cr exceeded the tolerance level in some sections. The tolerance level excess of those elements was regarded as the effect of the metamorphic rock which constituted the bed rock of the area. In order to identify the comprehensive enrichment pattern, the tolerable level was used in calculating the enrichment index. The enrichment index of harmful heavy metals showed that Granite gneiss area is 0.39, Porphyroblastic granite gneiss area 0.32, Biotite gneiss area 0.42, Migmatitic gneiss area 0.41, Tuff area 0.30, Andesite area 0.46, Conglomerate area 0.42, and Granite area 0.26. Those results showed that natural background of Gurye area had not been exposed to harmful heavy metal elements.

• Membrane Journal
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• v.30 no.1
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• pp.9-20
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• 2020

Membranes are used in most processes of biopharmaceutical production. It is used for pretreatment of other processes, separation of impurities in the process, virus removal, control of products concentration and buffer solution exchange. Virus filters play an important role in ensuring product efficacy and stability because viral contamination of biopharmaceuticals for humans is a sensitive issue that is directly related to serious clinical outcomes. Virus filters typically have complex multilayer structures made of various polymers such as surface-modified PVDF, PES, CRC. Depending on the manufacturer, filters have different pore structures and shapes, such as symmetric or asymmetric, and is used in the form of pleated membrane, flat sheets or hollow fibers. Virus filters are exclusively supplied by few foreign companies such as Asahi Kasei, Millipore, Pall and Sartorius. Replacing virus filters can be time consuming and expensive, including approval from regulatory agencies through validation. As localization has become important due to Japan's recent export regulations, it is necessary to increase the degree of technical independence.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1233-1246
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• 2018

Vibrio parahaemolyticus contamination causes serious foodborne illness and has become a global health problem. As a disinfectant, aqueous ozone can effectively kill a number of bacteria, viruses, parasites, and other microorganisms. In this study, three factors, namely, the aqueous ozone concentration, the exposure time, and the bacterial density, were analyzed by response surface methodology, and the aqueous ozone concentration was the most influential factor in the sterilization ratio. Under low aqueous ozone concentrations (less than 0.125 mg/l), the bacterial cell membranes remained intact, and the ozone was detoxified by intracellular antioxidant enzymes (e.g., superoxide dismutase and catalase). Under high aqueous ozone concentrations (more than 1 mg/l), cell membranes were damaged by the degree of peripheral electronegativity at the cell surface and the concentration of lactate dehydrogenase released into the extracellular space, and the ultrastructures of the cells were confirmed by transmission electron microscopy. Aqueous ozone penetrated the cells through leaking membranes, inactivated the enzymes, inhibited almost all the genes, and degraded the genetic materials of gDNA and total RNA, which eventually led to cell death.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.622-629
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• 2011

We investigated the effect of the discharged water from Bong Stream, which is located in the drainage area of Gangjinman area on the bacteriological water quality in the coastal area after rainfall events. Following 12.5 mm of rainfall, water discharged from Bong Stream had a very limited effect on bacteriological water quality in adjacent area and the affected area did not extend to the designated area. On the other hand, after 23 mm rainfall, the density of fecal coliform at stations located in the designated area was higher than at stations located in the adjacent area. The degree of bacteriological contamination at the surveyed stations in the coastal area after rainfall events did not show a relationship with distance from the shoreline. These results indicate that the direction of spread and the range of contaminants from the drainage area were affected by tides at the time of the survey. Therefore, a detailed survey of the effects of tides on the diffusion characteristics of the contaminants from Bong Stream is needed to establish a proper management plan for the surveyed area.

• The Korean Journal of Ecology
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• v.19 no.3
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• pp.261-270
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• 1996

To investigate the degree of contamination from Korean coastal region, the concentrations of Cu, Pb, Zn and Cd in sediments, seawater and oyster (Crassostrea gigas) at Masan Bay, Onsan Bay, Daesan industrial complex and their control areas were analysed. Values for sediments, seawater and oyster in the industrial complex coastal region were higher than those in the control area except for seawater in Daesan. The values for dissolved phasc of Cu, Pb, Zn and Cd in seawater showed 0.3~1.75 ${\mu}g/l$, 0.013~0.12 ${\mu}g/l$, 0.20~6.14 ${\mu}g/l$ and 0.007~0.021 ${\mu}g/l$, respectively. The concentrations of Cu, Pb, Zn and Cd in sediments werd 12.0~47.8 ${\mu}g/g$, 6.16~59.5 ${\mu}g/g$, 43.0~230 ${\mu}g/g$ and 0.52~11.2 ${\mu}g/g$, respectively. The concentrations of Cu, Pb, Zn and Cd in oyster showed 12.1~85.6 ${\mu}g/g$, 0.267~1.48 ${\mu}g/g$, 1, 070~3, 250 ${\mu}g/g$ and 3.23~7.71 ${\mu}g/g$, respectively. The contents of heavy metals in oysters at industrial complex coastal region showed that they were not seriously contaminated compared with those of Mussel Watch (1992).

• STI Policy Review
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• v.7 no.2
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• pp.106-131
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• 2016

The general purpose of this paper is to identify opportunities for and to measure existing collaboration on research and development between institutions from the countries of Asia and Latin America in FEALAC's framework, in the fields of biotechnology and nanotechnology and their convergence. The methodological approach includes scientific and technological surveillance and research seeking to identify both the R&D and innovation capacities of the countries as well as the degree of international cooperation between countries of the two regions; case studies and a study of the governance framework of international collaboration in R&D about issues considered global challenges. The study has three main findings. First, nanotechnology, biotechnology and their convergence contribute to solving the problem of contamination by heavy metals affecting most of the countries that are part of FEALAC and to address problems arising from the accelerated rate of energy consumption, which also contributes to environmental damage. In this scenario, important business opportunities arise from the adaptation and development of bio-refinery technologies. Second, the scientific relationship between FEALAC countries, mainly between Asian and Latin American countries, is weak as can be seen in research for articles and patents. But there is plenty of room and potential for improvement. Third, current and upcoming joint R&D programs and projects should be linked both to existing governance structures and to new ones that serve as experiments of STI public policy regarding innovative management of intellectual property and capacity building. Practical implications are included in lessons learned and a set of recommendations involving a couple of proposals. One proposal calls for research and innovation in promising fields for international cooperation. Another proposal creates mechanisms in the governance framework for sharing knowledge, capacity building, and funding.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.2
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• pp.108-115
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• 2002

Pollutants discharge modeling was carried out in the watershed of Mankyung and Dongjin rivers. The watershed and pollutants source information extracted and analysed by the GIS tool was used as the model input parameters. This model was calibrated by comparison of the measured and computed monthly freshwater discharge and water quality(WQ) concentration. The compared WQ data are the ten-year-mean WQ concentration and monthly WQ concentration in 1999. The results show that the watershed runoff is underestimated in summer season, although the seasonal trends are relatively well estimated. The WQ concentrations were also relatively well estimated except Iksancheon. The computed concentration was much lower than the observed concentration in Iksancheon because of the effect of polluted sediment. Thus, the effects of polluted sediment on water column need further study through measuring and analysing the degree of the sediment contamination.

• Environmental Analysis Health and Toxicology
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• v.26
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• pp.7.1-7.9
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• 2011

Objectives: This study was conducted to examine the relationship between crude oil exposure and physical symptoms among residents participating in clean-up work associated with the Hebei Spirit oil spill, 2007 in Korea. Methods: A total of 288 residents responded to a questionnaire regarding subjective physical symptoms, sociodemographic characteristics and clean-up activities that occurred between two and eight weeks after the accident. Additionally, the urine of 154 of the respondents was analyzed for metabolites of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) and heavy metals. To compare the urinary levels of exposure biomarkers, the urine of 39 inland residents who were not directly exposed to the oil spill were analyzed. Results: Residents exposed to oil remnants through clean-up work showed associations between physical symptoms and the exposure levels defined in various ways, including days of work, degree of skin contamination, and levels of some urinary exposure biomarkers of VOCs, metabolites and metals, although no major abnormalities in urinary exposure biomarkers were observed. Conclusions: This study provides evidence of a relationship between crude oil exposure and acute human health effects and suggests the need for follow-up to evaluate the exposure status and long-term health effects of clean-up participants.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.323-329
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• 2011

BACKGROUND: The conazoles, difenoconazole, diniconazole, hexaconazole, penconazole and tetraconazole are a large class of synthetic fungicides used extensively for foliage and seed treatments in agricultural crops. The extensive use of conazoles has brought concerns on the potentiality of environmental contamination and toxicity. Thus studies on the development of methods for monitoring the conazoles are required. METHODS AND RESULTS: A modified quick, easy, effective, rugged and safe (QuEChERS) method was involved in sample preparation. Quadrapole time of flight mass spectrometer (Q-TOF MS) in electron spray ionization (ESI) mode was employed to determine conazoles in garlic samples. The limit of detection (LOD) and limit of quantification (LOQ) of conazoles by Q-TOF-MS ranged from 0.001 to 0.002 mg/L and 0.002 to 0.005 mg/L, respectively. Q-TOF-MS analysis exhibited less than 2.6 ppm error of accurate mass measurements for the detection of conazoles spiked at 0.05 mg/L in garlic matrix. Recovery values of conazoles fortified in garlic samples at 0.02, 0.05 and 0.1 mg/L were between 79.2 and 106.2% with a maximum 11.8% of standard deviation. No detectable conazoles were found in the domestic market samples by using the Q-TOF-MS method. CONCLUSION(s): High degree of confirmation for conazoles by accurate mass measurements demonstrated that Q-TOF-MS analysis combined with a QuEChERS method may be applicable to simultaneous determination of conazoles in garlic samples.

• Journal of Apiculture
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• v.34 no.4
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• pp.315-323
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• 2019

Large amounts of sludge produced by paper mill industries represent one of the most serious environmental problems in the world. Recently, beekeepers living in the neighborhood of the paper mill in Hwasan County, Youngcheon city, GB, Korea, became alarmed that honey bee colonies were dying off suddenly across the neighborhood. A preliminary study was conducted to evaluate the toxicity (oral, fumigation, repellent) of recycled solid paper mill sludge (SPMS) and leachate paper mill sludge (LPMS) to honey bee workers under laboratory conditions, and to analyze the volatile organic compounds(VOC). The SPMS and LPMS were separately subjected to a liquid-liquid extraction (LLE) at three temperatures to extract VOC(highest VOC yields: 1.52% SPMS and 0.34% LPMS). A total of 70 chemicals were detected in the VOC of paper mill sludges, of which 49 and 21 volatile organic compounds from SPMS and LPMS, respectively. The SPMS was dominated by high degree presence of stanols (saturated sterols), such as cholestanol, cholestan-3-ol and also saturated hydrocarbons. However, LPMS was characterized by the absence of sterols. Both SPMS and LPMS showed an influence on the olfactory behavior of honey bee on Y-tube assay, with repulsion rates of 72 and 68%, respectively. Both SPMS and LPMS at concentration of 100mg/mL caused higher honey bee oral mortality than the untreated controls at 48, 72, 96 and 120 hours after treatment(highest oral mortality at 120 hr: 85.74%(SPMS); 93.51 % (LPMS)). A similar pattern was observed when honey bees were tested to fumigant toxicity. Both SPMS and LPMS caused significant higher mortality than the untreated control 24 hour after the exposure (highest fumigation mortality at 120 hr: 69.4% (SPMS); 56.8% (LPMS)). These preliminary results indicated that paper mill sludge could be partly responsible for sudden death and disappearance of honey bees, especially in hot humid summer days. With climate change, the risk of environmental chemical exposure to honey bee would pose greater attention.