• 생명과학회지
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• 제19권3호
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• pp.373-377
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• 2009

환경시료에서 많이 분리되는 장내바이러스 중 폴리오바이러스, 콕사키바이러스, 에코바이러스를 이용하여 정수처리 공정별 제거율을 조사하였다. 양성 시료로 사용된 바이러스들의 회수율은 72-108%의 범위로 나타났다. 이들 3종 바이러스들을 대상으로 정수처리공정별 제거효율을 조사한 결과 약 99%의 바이러스가 침전단계에서 제거되어졌고, 후오존과 BAC 여과과정을 거치면서 100% 제거되어짐을 확인할 수 있었다. 6개의 세포주를 사용하여 바이러스별 감수성을 조사한 결과 폴리오바이러스는 BGMK 세포주, 콕사키바이러스는 Vero 및 BGMK 세포주가 다른 세포주에 비해 높은 감수성을 나타내었고, 반면 에코바이러스는 RD 세포주에서 가장 분리가 용이하였다.

• 한국물환경학회지
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• 제18권3호
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• pp.327-336
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• 2002

Disinfection process in water treatment plants (WTPs) is one of the most important step in order to inactivate waterborne disease. However, what is the necessary disinfection in WTPs was not properly established in Korea. This study was conducted to evaluate disinfection performance in nationwide water treatment plants (n=474). Disinfection requirement based on the SWTR (Surface Water Treatment Rule) of the U.S. (1-log Giardia removal) was chosen in estimating the compliance. The scope of unit process for evaluating disinfection performance includes postdisinfection process in clearwells, pipeline, and storage tank. The worst water quality condition in individual WTPs was applied for the disinfection performance evaluation. The major results are as follows. First, it was appeared that 184 WTPs (39 %) provided insufficient disinfection performance. Disinfection performance was significantly improved during past 2 years. The ratio of the number of WTPs providing insufficient disinfection performance in 1999 and 2001 was 78 % and 41 %, respectively. One of major factors for this improvement was due to the improvement of $T_{10}/T$ value in clearwell, as a result of modification of clearwell facility. Second, if disinfection criteria is 3-log Giardia inactivation at worst water quality condition, then 19 % of all WTPs can not meet this disinfection criteria. And if disinfection criteria is strengthened to 4-log Giardia inactivation, then 58 % of all WTPs can not meet this disinfection criteria. Since disinfection criteria is decided by contamination level of Giardia in source water, it also needs the investigation of Giardia occurrence in source water.

• 상하수도학회지
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• 제30권3호
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• pp.285-291
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• 2016

There has been an accelerating increase in water reuse due to growing world population, rapid urbanization, and increasing scarcity of water resources. However, it is well recognized that water reuse practice is associated with many human health and ecological risks due to numerous chemicals and pathogenic microorganisms. Especially, the potential transmission of infectious disease by hundreds of pathogenic viruses in wastewater is one of the most serious human health risks associated with water reuse. In this study, we determined the response of different bacteriophages representing various bacteriophage groups to chlorination in real wastewater in order to identify a more reliable bacteriophage indicator system for chlorination in wastewater. Different bacteriophages were spiked into secondary effluents from wastewater plants from three different geographic areas, and then subjected to various doses of free chlorine and contact time at $5^{\circ}C$ in a bench-scale batch disinfection system. The inactivation of ${\phi}X174$ was relatively rapid and reached ~4 log10 with a CT value of 5 mg/L*min. On the other hand, the inactivation of bacteriophage PRD1 and MS2 were much slower than the one for ${\phi}X174$ and only ~1 log10 inactivation was achieved by a CT value of 10 mg/L*min. Overall, the results of this study suggest that bacteriophage both MS2 and PRD1 could be a reliable indicator for human pathogenic viruses for chlorination in wastewater treatment processes and water reuse practice.

• 한국어병학회지
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• 제27권2호
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• pp.115-125
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• 2014

본 연구에서는 수온변화에 따른 비소 (As) 노출의 영향을 틸라피아 Oreochromis niloticus의 간과 아가미에서 항산화 방어기작 (antioxidant defense system)을 통해 알아보고자 한다. 틸라피아를 수온이 각각, 20, 25 및 $30^{\circ}C$ 일때, 비소 농도 0, 200 및 $400{\mu}g/L$에서 10일간 노출시킨 후, glutathione (GSH) levels, glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-treansferase (GST) 효소 활성을 측정하였다. 비소 노출 이후, 틸라피아의 간과 아가미에서 이들 항산화 효소는 수온 변화에 따라 유의하게 변화하였다. 특히, 다른 온도구간에 비하여 수온이 $30^{\circ}C$ 일 때, 비소에 노출된 틸라피아의 간에서 이들 효소의 변동폭은 가장 유의하게 증가하였다. 즉, 본 연구는 틸라피아의 간과 아가미에서 GSH 및 항산화 효소인 GR, GPx 및 GST에 미치는 비소의 영향은 수온 상승이 동반되었을 때, 어류의 산화 스트레스에 대한 방어 기작의 감소를 촉진시켰음을 보여준다.

• Journal of the Korean Wood Science and Technology
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• 제21권4호
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• pp.7-28
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• 1993

본 총설에서는 새로운 방부제와 방부처리 기술의 현재 발전 동향을 요약, 보고한다. 많은 새로운 방부제들이 약제의 독성 측면에서 환경적인 충격을 완화시킬 수 있는 잠재성을 가지고 있지만, 방부제로서 상업화되기 위해서는 이러한 약제들은 약제의 효능과 환경 안전성 간의 몇 가지 상호 조정 관계가 반드시 해결되어야 한다. Ammoniacal copper 계통의 방부제들이 지접부 사용에 적합한 새로운 수용성 방부제들의 주종을 이루고 있으며, 기존의 유용성 방부제들을 물에 용해한 emulsion 형태도 지접부 사용의 가능성을 보여 준다. 새로운 유용성 방부제 중에서 copper naphthenate, substituted isothiazolones, chlorothalonil, oxine copper가 지접부 사용을 위한 최상의 후보로 평가되고 있다. 유용성 방부제를 emulsion 형태로 사용하는 것은 유용성 방부제에 사용되는 석유 계통 용제의 소비를 감소시키기 때문에 중대한 의미를 가진다. 방부제들의 효능을 개선하고 강화시키기 위해 사용되는 첨가제들도 본 총설에서 거론된다. 재질개량을 위해 사용되는 비통상적인 방법(nonconventional system)들도 생물학적 열화 및 기상열화에 대한 저항성을 부여하여 목재의 사용수명을 증가시킨다. 전처리 공정에서 침상 자상처리(Needle incising)와 레이져 자상처리는 난주입 수종의 처리도를 개선시킬 수 있는 잠재성을 가지고 있다. 처리기술에 있어서 여러 가지 혁신적인 변화들은 기존의 처리 schedule을 조성함에 그 기본을 두고 있다. 난주입 수종의 처리도 개선은 pulsation법이나 고압 약제 분사법 (high energy liquid jets) 같은 고압을 적용하는 처리법에 의해서 달성된다. 미래의 처리공장들은 방부제를 기체상태로 또는 물질의 임계점 이상에서 방부제를 처리할 수도 있다. 이러한 새로운 접근은 외관이 깨끗하고, 처리도도 매우 양호한 처리재를 생산하는데 일조하리라 기대한다. 환경에 대한 대중적인 지대한 관심은 앞으로 목재 방부산업에 큰 영향을 미칠 것으로 보인다. 결과적으로 방부제의 처리목재내 가속 정착에 관한 연구에 상당한 노력이 투자될 것이다. 처리 후 가공에 관한 다른 주요한 연구는 방부제 처리 후 실시되는 재건조가 처리재의 역학적 성질에 미치는 영향에 대한 것이다.

• 한국가구학회지
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• 제26권2호
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• pp.122-129
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• 2015

In previous study, VOC emission characteristics of coating materials for wood finishing were conducted and results showed that eco-friendly products has about 15~46% lower TVOC emission than typical products. In this study, lower TVOC emitted coating materials were applied on pine and then changes of VOC emission characteristics from pine with treatments were determined. Non-treated pine emitted $604.7{\mu}g/m^2h$ of TVOC that contained 66% of NVOC ($399.7{\mu}g/m^2h$). However, $V_2$ finished pine showed no NVOC emission rather than AVOC emission that consisted of Toluene, Ethylbenzene, m,p-Xylene, o-Xylene, 1,2,4- Trimethylbenzene. All coating materials inhibited ${\alpha}$-Pinene emission which originally from pine, but waterborne stain ($W_1$ and $W_3$) showed lower disruption of that emission. Moreover, $W_3$/wood showed higher NVOC emission such as ${\alpha}$-Terpinol, Terpinen-4-ol which are known as antioxidant substrates. Based on results, VOC emission characteristic of pine was significantly affected by coating materials with negatively in terms of ${\alpha}$-Pinene emission or positively in terms of NVOC emission. Therefore, coating material is important factor for indoor air quality when it would apply on wood products. For the future study, VOC emission characteristic of coated wood will be conducted continuously.

• 한국수산과학회지
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• 제47권6호
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• pp.874-881
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• 2014

A laboratory experiment was conducted to determine chronic effects of waterborne copper exposure on rock bream Oplegnathus fasciatus using a panel of enzymes. The activities of the following biochemical biomarkers were determined at different concentrations of $CuSO_4$ for 10 and 20 days: alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) in plasma; antioxidant enzymes including glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in liver and gills; and acethylcholinesterase (AChE) in brain and muscle. After exposure to two $CuSO_4$ concentrations (200 and $400{\mu}g/L$), the activities of plasma ALT in the fish showed a tendency to increase with AST and LDH, depending on $CuSO_4$ concentration. Additionally, GSH levels and SOD activities significantly increased, depending on $CuSO_4$ concentrations in liver and gills. This involved the inactivation of reactive molecules formed during oxidative stress, which could provide protection against oxidative damage induced by $CuSO_4$. However, GPx and AChE activities significantly decreased with $CuSO_4$ in liver and gills. In conclusion, these enzymes may represent convenient biomarkers for monitoring heavy metal pollution in coastal areas. Such chronic exposure studies are necessary for improving our understanding of complementary or deleterious effects of pollutants, and for developing metal toxicity biomarkers.

• 대한지리학회지
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• 제44권4호
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• pp.497-509
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• 2009

삼국사기 신라본기를 통하여 고대(BC 57$\sim$AD 935)에 발생한 가뭄, 홍수, 역질, 메뚜기의 내습 그리고 지진 등 자연재해 기록을 유형별로 분석하여, 각각 인간생활에 어떻게 영향을 미치고 상호 관련되어 있는지 검토하였다. 농업생산에 가장 크게 영향을 미친 것은 가뭄이며, 홍수의 영향은 미약하였다. 고대에는 곡저평야에 경작지를 만들며 하천 범람으로부터 안전한 공간에 도시와 마을을 조성하였으므로 대부분의 홍수가 파괴적인 재해는 아니었다. 메뚜기 떼는 가뭄이 발생한 시기에 출현하는 빈도가 높았다. 고대의 역질은 기근, 홍수, 가뭄과 관계 없이 발생한다. 이것은 당시 수인성 전염병이 주기적으로 발생하였으며, 통일 이후 도시화로 인해 수도에 인구가 집중되면서 전염병의 발생이 지속적으로 증가하였다. 신라 천 년 고대 동안의 가뭄 현상은 두 번의 주기가 인정되며 대략 500년의 시간 간격으로 발생하였다.

• 한국패류학회지
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• 제20권1호
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• pp.93-105
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• 2004

Arkshell clams, Scapharca broughtonii, are economically important edible bivalves and widely cultivated in the Southern coast of Korea. Recently, the production of S. broughtonii has been dramatically decreased and various reasons including chemical pollution were suspected to be related to the production declines. However, it remains unknown whether the chemical pollution levels of the surrounding environments were high enough for the biological and ecological disturbance for the population of S. broughtonii, because no systematic toxicological study using S. broughtonii has been conducted previously. In the present study, we exposed arkshell clams, S. broughtonii to various waterborne pollutants including heavy metals (Cd, Cu and Hg), ammonia and organotins (tributyltin and triphenyltin) to determine the effect concentrations of these pollutants for the survival of S. broughtonii for 20 days. The median lethal concentrations ($LC_50$) of S. broughtonii were 2.1 mg/l for Cd, 0.065 mg/l for Cu, 0.40 mg/l for Hg, 79.4 mg/l for total ammonia (1.9 mg/l for unionized ammonia), 0.5 ${\mu}$g/l for TBT, and 14${\mu}$g/l for TPhT. Lethal toxicity of the most pollutants increased with both exposure duration and concentration. The toxicity of TBT was greatest for S. broughtonii, followed by TPhT > Cu > Hg > Cd > ammonia. The sensitivities of S. broughtonii to heavy metals and TBT were comparable to those of other aquatic organisms, but they were relatively tolerable to ammonia. The environmental concentrations of the tested pollutants were compared with the effect concentrations of those for the survival of S. broughtonii to assess the potential risks of the pollutants in the field conditions.

• Fisheries and Aquatic Sciences
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• 제13권1호
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• pp.71-78
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• 2010

We investigated the effect of Cu exposure on the activities of protective antioxidant enzymes in the gills and digestive glands of the manila clam Ruditapes phillippinarum exposed to subchronic concentrations (0, 20, 40, and $80{\mu}gL^{-1}$) of waterborne Cu. No mortality occurred during the experimental period, and no significant condition index differences were observed in any exposure group compared with the control. No significant differences were observed in the digestive glands and gills of the clams observed during 15 days of exposure, but after 30 days, the SOD activity in the gill showed a significant difference between the $80{\mu}gL^{-1}$ Cu-exposed group and the control. GPx activities in the digestive glands and gills were significantly lower after 30 days of Cu exposure. Gill GR activity in the high-exposure group ($80{\mu}gL^{-1}$) was significantly elevated compared with that in the control group. GST activities in the digestive glands of all groups did not change over 30 days. However, GST activity in the gill at $80{\mu}gL^{-1}$ Cu was significantly higher after 15 and 30 days of exposure. GSH activities in the gill showed patterns similar to those of GST activities during exposure periods. In the digestive glands, GSH activity was higher only at $80{\mu}gL^{-1}$ after 30 days exposure. In digestive glands and gills, the MDA levels of clams exposed to $80{\mu}gL^{-1}$ Cu were significantly higher after 30 days of exposure.