• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.1
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• pp.39-51
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• 2011

Acute toxicity test and behavioral change analysis of seawater acclimated Japanese medaka were conducted to identify the brine effects on fish by seawater desalination. 7 day acute toxicity test of brine revealed linear concentration-response relationship from 40.0~80.0 psu treatment groups. There was no significant brine effect for 30-40 psu groups and mass mortality was observed from >50 psu exposure (7-day $LC_{50}$=51.4 psu). Images from the real time camera system were analyzed to observe the changes in behavioral patterns of medaka exposed to various salinity. 40.0 and 50.0 psu exposed groups were stabilized in behavioral patterns after 3.1 and 4.6 hours, respectively and 60.0 psu group showed sharp increase in activity during first 12 hours and 50% mortality thereafter. Similar patterns were observed to 70 and 80 psu groups and both experimental groups showed 100% mortality within 12 hours. Acute toxicity test and behavioral patterns showed very similar toxicity results which revealed the increases in mortality and behavioral activities from 50.0 psu. This critical salinity for fish impacts must be implemented to brine discharge strategy by seawater desalination into the coastal area. Also, we recommend that real time camera monitoring system must be a useful tool for early warning of fish toxicity for other applications. This research was funded by Ministry of Land, Transport and Maritime Affairs, Korea.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.70-79
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• 1998

본 실험의 목적은 다양한 펄프제조 조건과 여러 형태의 리그노 셀루로우스 성분이 펄프폐수의 혐기성 생분해에 미치는 영향을 규명하는 것이다. 실험에 사용된 폐수는 일반적으로 펄프 제조시에 발생되는 폐수를 대상으로 하였으며, 펄프제조 조건은 TMP공정과 소다 펄프공정을 적용하였다. 혐기성 생분해 가능성 시험 및 독성실험은 $35\pm 2\circ$C의 중온상태에서 입상슬러지를 식종물질로 사용한 회분식 반응조를 이용하였다. TMP공정의 배출되는 폐수는 산으로의 전환율이 총 COD기준으로 68-87%로 매우 높은 혐기성 생분해 가능성을 보였다. 그리고 TMP공정폐수는 일반적으로 제지폐수 처리시 독성농도라고 알려진 농도에서도 메탄생성균에 독성을 주지 않았고, 또한 COD 10g/l의 농도에서도 처리에 저해가 일어나지 않았다. 반면에, 알카리성 상태에서 준비된 펄프폐수의 경우는 생분해성이 매우 낮아서 대략 50%정도의 산전환율을 보였으며, 메탄생성균에 상당한 저해를 주었다. 메턴생성균의 활성도에 50%저해를 주는 농도는 2.1~5.4 gCOD/l였다. 알카리성 펄프폐수의 독성에 대한 추가 실험결과 펄프내 wood resin이 산이나 중성 pH부근에서는 잘 용해가 되지 않고 알카리성 상태에서 쉽게 용해되어 메탄생성균에 저해를 나타내는 것으로 밝혀졌다. 따라서 펄프제조시 나무성분이 알카리성분과 접촉할 경우 후속하는 혐기성 처리공정의 메탄생성균에 심각한 저해를 줄 수 있다.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.374-384
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• 2016

Concern about air pollution is gradually rising up in domestic and foreign, automotive and fuel researchers are trying to reduce vehicle exhaust emissions, through a lot of approaches, which consist of new engine design and innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research is proceeding by two main issues : exhaust emissions and PM particle emissions of gasoline vehicle. Exhaust emissions, non-regulated emissions and PM (particulate matter) particles of automotive are causing many problems which ambient pollution and harmful effects on the human body. The main particulate fraction of automotive exhaust emissions consists of small particles. Because of their small size, inhaled particles can easily penetrate deep into the lungs. The rough surfaces of these particles make it easier for them to combine with other toxins in the environment. Thus, the hazards of particle inhalation are increased. Based on the oxygenated fuel additive types (MTBE, Bio-ETBE, Bio-ethanol, Bio-butanol), this paper discussed the influence of oxygen contents on gasoline vehicle exhaust emissions, non-regulated emissions and nano-particle emissions. Also, this paper assessed exhaust emission characteristics at 2 type test modes. The test modes were FTP-75 and HWFET. All measurement items be verified less than the value of regulated emissions. It could be known difference increase and decrease by each measurement item depending on increase the oxygen contents.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.361-364
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• 2012

최근의 건축물은 다양한 소재의 마감재를 사용함으로서 화재 발생시 다양한 연소가스를 배출한다. 이때 건축물 내부의 화재에 노출된 재실자는 열 및 화상의 위험성과 함께 연기 및 독성가스의 피해를 받기 쉽다. 본 연구에서는 건축물 화재시 발생될 수 있는 HCl에 대한 표준가스를 제작하여 가스유해성시험을 수행하고, HCl 표준가스에 노출된 실험용 쥐의 표적장기적출실험을 수행하였다. 이를 통해서 유독가스에 노출된 실험용 쥐의 해부를 통한 표적장기-심장(Heart), 간(Liver), 폐(Lung), 비장(Spleen), 신장(Kidney), 흉선(Thymus)-의 손상여부와 KS F 2271에 의한 평균행동정지시간과의 관계를 분석하였다.

• Journal of the Korean Institute of Gas
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• v.21 no.6
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• pp.88-95
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• 2017

The usage of toxic gas in Korea is increasing in the development of high-tech industries such as semiconductors, displays and solar panels. The recent survey of domestic toxic gas consumption indicates an increase in annual average of 12.4 percent, but it is still focused on usage, and it is negligent in safety and treating the post. In September 2012, an accident occurred in Gu-mi involving hydrofluoric acid leak demonstrates the absence of safety management. Due to the incident, the government, industry and academia have been interested in chemical substances(toxic gas), and the government-led safety management has been established and implemented, but there are still a lot of safety blind spots. The purpose of this study is to develop effective measurement methods for the destruction or removal efficiency of gaseous materials emitted from the Scrubber used in the semiconductor and display industries. Also, this study demonstrated how toxic gas facilities can be applied without error by verification test for the measurement method guideline of the destruction or removal efficiency of the green-house gas reduction facility in the semiconductor and display industries used by the National Institute of Environmental Research and the UNFCCC, and suggested the differentiated measurement methods for toxic gas reduction facilities, and the third party certification for safety facilities is needed to prevent toxic gas accidents.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.2
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• pp.67-78
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• 2007

The eye irritant test of lens washing agent, CLIWELL$^{TM}$ was conducted using Draize methods according to KFDA Guidelines. In addition, to test the potential toxicity of test articles, the ratio of inflammatory cells and non-inflammatory epitheloid cells was also observed using smear cytology methods against ocular discharge. At sacrifice, the histopathological changes on Cornea, Iris, Retina and Sclera were also observed in all animals. Slight irritancy of cornea and conjunctiva was observed at 1, 2 and 3 days after dropping in non-washing group. The MIOI of these points are detected as 4.50, 1.67 and 0.67, respectively. In washing group, slight irritancy of cornea and conjunctiva were observed at 1 and 2 days after dropping with MIOI as 0.67, respectively. Therefore, CLIWELL$^{TM}$ was considered as non-irritating materials because the MIOI is detected below 5.00 throughout the whole experimental periods in both washing and non-washing groups and the IAOI was also detected as 4.50. Except for significant increase of the inflammatory cell ratios in ocular discharge at 1 day after dropping of non-washing group compared to that non-treated intact eyes, no meaningful changes on smear cytology of ocular discharges are observed in this study. In addition, no abnormal histopathological changes on the cornea, iris, retina and sclera were also detected in CLIWELL$^{TM}$ dropping group compared to that of non-treated intact eyes.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.4
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• pp.299-310
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• 2006

The eye irritant test of lens washing agent, $SOLOCARE^{TM}$ was conducted using Draize methods according to KFDA Guidelines 1999-61. In addition, to test the potential toxicity of test articles the ratio of inflammatory cells and non-inflammatory epitheloid cells were also observed using smear cytology methods against ocular discharge. At sacrifice, the histopathological changes on Cornea, Iris, Retina and Sclera were also observed in all animals. Slight (1~2 degrees) irritancy of cornea and conjunctiva were observed at 1, 2 and 3 days after dropping in non-washing group. The MIOI of these points are detected as 4.33, 3.33 and 2.00, respectively. In washing group, slight irritancy of cornea and conjunctiva were restricted to 1 and 2 days after dropping with MIOI as 3.00 and 1.33, respectively. Therefore, $SOLOCARE^{TM}$ was also considered as non-irritating materials because the MIOI is detected below 5.00 throughout the whole experimental periods in both washing and non-washing groups and the IAOI is also detected as 4.33 (1 day after dropping). No meaningful changes on smear cytology of ocular discharges are observed in this study compared to that of non-treated intact eyes. In addition, no abnormal histopathological changes on the cornea, iris, retina and sclera were also detected in $SOLOCARE^{TM}$ dropping group compared to that of non-treated intact eyes.

• Journal of Life Science
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• v.26 no.11
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• pp.1253-1258
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• 2016

Although major advances have been achieved in our understanding and treatment of diseases in many areas of medicine, relatively few improvements have been made in the area of gastrointestinal (GI) motor function. The dried root of Codonopsis pilosula (Franch.) Nannf. (CP) has been used as a traditional folk medicine for improving poor GI function in East Asia, including China and Korea. In the present study, neither aqueous (CP-W) nor ethanolic (CP-E) extracts of CP showed significant toxicity, even at an oral dose of 5 g/kg to mice. The effects of CP-W and CP-E on GI motor function were investigated by measuring in vivo the gastric emptying rate (GER) and intestinal transit rate (ITR) in mice. In normal mice, the ITR was significantly increased by CP-W in a dose-dependent manner, whereas the GER was not significantly affected by any CP extracts. The ITR was significantly retarded in the mice with experimental GI motility dysfunction (i.e., peritoneal irritation by acetic acid) compared with that in normal mice. However, the retardation was significantly recovered by the pre-treatment of CP-W in a dose-dependent manner. The above results suggest that CP-W might be a potential prokinetic agent preventing or alleviating GI motility dysfunctions in human patients.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.271-279
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• 2009

Vinyl chloride (VC) is a known human carcinogen, and it is released to multi-environmental media via several exposure routes. VC was potentially evaluated as a water quality pollutant based on human health risk assessment in Korean water environments. In this study, we investigated physicochemical and toxicological properties of VC, human health and ecological risk assessment, and the regulation of VC as a water quality pollutant in developed countries. Currently there are no standard or guideline values of VC in Korean legal system for the protection of human health and aquatic ecosystem, except that it is designated as a specific toxic substance and a water quality pollutant. Human health risk assessment of VC was previously performed based on the limited water quality monitoring data. The monitoring level of VC in Korean water system is more higher than other countries'. VC was assessed as potential hazardous chemical based on the US EPA's cancer risk assessment. There were a few ecotoxicity data of VC available using very limited kinds of aquatic organisms, and the toxicity results obtained seem to be overestimated without considering the losses of VC in open exposure system. Therefore it is needed to monitor the VC in various areas and to carry out the ecotoxicity research using multi-level organisms. We expect that these results can be useful information for implementing VC as a water quality pollutant in legal system for the protection of human health and aquatic ecosystem in near future.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.625-639
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• 2019

Microplastics are one of the substances threatening the marine ecosystem. Here, we summarize the status of research on the effect of microplastics on marine life and suggest future research directions. Microplastics are synthetic polymeric compounds smaller than 5 mm and these materials released into the environment are not only physically small but do not decompose over time. Thus, they accumulate extensively on land, from the coast to the sea, and from the surface to the deep sea. Microplastic can be ingested and accumulated in marine life. Furthermore, the elution of chemicals added to plastic represents another risk. Microplastics accumulated in the ocean affect the growth, development, behavior, reproduction, and death of marine life. However, the properties of microplastics vary widely in size, material, shape, and other aspects and toxicity tests conducted on several properties of microplastics cannot represent the hazards of all other microplastics. It is necessary to evaluate the risks according to the types of microplastic, but due to their variety and the lack of uniformity in research results, it is difficult to compare and analyze the results of previous studies. Therefore, it is necessary to derive a standard test method to estimate the biological risk from different types of microplastics. In addition, while most of the previous studies were conducted mostly on spheres for the convenience of the experiments, they do not properly reflect the reality that fibers and fragments are the main forms of microplastics in the marine environment and in fish and shellfish. Furthermore, studies have been conducted on additives and POPs (persistent organic pollutants) in plastics, but little is known about their toxic effects on the body. The effects of microplastics on the marine ecosystems and humans could be identified in more detail if standard testing methods are developed, microplastics in the form of fibers and fragments rather than spheres are tested, and additives and POPs are analyzed. These investigations will allow us to identify the impact of microplastics on marine ecosystems and humans in more detail.