• 농약과학회지
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• 제16권4호
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• pp.369-375
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• 2012

황토유황합제는 우리나라에서 농작물 생산에 살균살충작용을 가지는 것으로 알려져 친환경유기농자재로 널리 사용되고 있으나, 알칼리성이 강하여 작물에 약해를 보일 뿐 아니라 농업자의 피부 및 안점막에 자극성이 있는 것으로 보고되고 있어 제품으로서의 안전성에 대한 우려가 높다. 본 연구에서는 작물의 약해를 저감하기 위해 pH를 조정하여 제조한 황토유황합제 3종(pH 9, pH 10, pH 11)의 인축 급성독성시험을 시행하여 인체 안전성을 확인함으로써 친환경유기농자재 개발시 최적의 제품 선정에 기초자료로 활용하고자 하였다. 랫드를 이용한 급성경구독성시험 결과 황토유황합제는 $LD_{50}$이 2,000 mg/kg b.w. 이상이었으며, 급성경피독성시험 결과 또한 모두 4,000 mg/kg b.w. 이상인 저자극성으로 분류되었다. 피부 및 안점막자극성 시험 결과에서도 모두 저자극성으로 구분되었으며 pH 9~11 범위에서 제품간 독성분류의 차이는 나타나지 않았다.

• 한국환경보건학회지
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• 제30권4호
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• pp.347-351
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• 2004

A battery of sediment bioassays was performed for the sediments from the intertidal flat zone along the middle west coast of Korea to assess their potential toxicity. In the bioassays, three crustaceans, Daphnia magna, Nitocra spines, and Hyalella aztec a were exposed to $16\%$ sediments (wet weight) collected from 14 sites. Immobility($\%$) was checked as an endpoint after 24- and 48-h exposure of Daphnia magna and after 96-h exposure of Hyalella azteca and Nitocra spines. Among the three bioassays, the 48-h Daphnia bioassay showed the most distinct differential sensitivity in relation to sediment contamination, while the Nitocra and the Hyalella bioassays failed to show the differential sensitivity properly among the sites classified as polluted. Significantly different levels of immobility ($\%$) were obtained between the sites classified as chemical/nutrient polluted and the sites classified as non-polluted in the Daphnia bioassays, but not in the Nitocra bioassay and the Hyalella bioassay. Some differences of toxic response to the same sediments among bioassays were observed, suggesting that there may be a chemical specificity of response sensitivity to sediment toxicity, due to differences in bio-availability of sediment toxicants among test species.

• 대한화학회지
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• 제41권5호
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• pp.239-245
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• 1997

광유로부터 polychlorinated biphenyls(PCBs)를 제거할 수 있는 가능성을 평가하기 위해 활성탄을 이용한 흡착반응을 연구하였다. 염소원자의 치환이 비교적 적은 PCBs로 구성되어 있는 Aroclor 1242의 흡착 효율은 95% 이상이었으나, 많은 염소원자들로 치환된 Aroclor 1260은 상당히 낮은 75%의 효율을 나타내었다. 관찰된 차이점은 평면이나 비평면 구조를 갖고 있는 PCBs의 기하학적인 구조에 기인한다. 실제로 평면구조 PCBs의 농도는 Aroclor 1260에서보다도 Aroclor 1242에서 훨씬 높다. PCBs의 독성은 주로 평면 구조와 관련되어 있기 때문에, 활성탄에 의한 평면구조 PCBs의 우선적인 흡착은 활성탄의 처리를 통해 독성의 감소가 성취될 수 있다는 것을 보여준다. 독성 감소의 효율은 Toxicity Equivalence Factor(TEF)를 써서 평가하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.103-106
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• 2001

Bioluminescent bacteria fusing the stress promoter and lux gene have been developed as a toxicity biosensor. The light emitting bioluminescent bacteria have been used to measure the toxicity of many different chemicals. In this study, specially, DPD2540 (fabA::luxCDABE) was used to detect and classify phenolic toxicity to the cells membrane fatty acids, and then the relationship between phenolic toxicity and the distribution of various phenols in the cell was determined, with a model and equations provided. In addition, to show the possibility of detecting and classifying the toxicity of a chemical mixture, which may be present in wastewater, various bioluminescent bacteria having different stress promoters were used and their distinct response to the sample mixture was measured. To extend the applicable area of these bioluminescent bacteria to field, the portable biosensor using freeze-drying methods was developed and confirmed successfully.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권6호
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• pp.426-432
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• 2001

Perstractive fermentation is a good way to increase the productivity of bioreactors. Us-ing Propionibacteria as the model system, the feasibility of using supported emulsion liquid mem-brane(SELM) fro perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for perparing the SELM. The more polar a solvent, is the higher the par-tition coefficeint However, toxicity of a solvent also increases with its polarity. CO-1055(indus-trial decanol/octanol blend)has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria, A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The results confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extrac-tion and allows the use of a non-toxic solvent with low partition coefficient.

• 한국산업보건학회지
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• 제28권1호
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• pp.43-50
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• 2018

Objectives: This study was performed to observe the toxicological changes caused by a single exposure to benzo[a]pyrene. Methods: Based on the results of a preliminary study, 300 mg/kg was set as the middle dose. A highest dose of 2,000 mg/kg and a lowest dose of 50 mg/kg were selected based on GHS guidelines. Benzo[a]pyrene was orally administered once to female and male SD rats at dose levels of 50, 300, and 2,000 mg/kg(body weight). All animals were monitored daily for clinical signs and mortality over 14 days. Hematological and biochemical values were examined as well. Results: There were neither dead animals nor significant changes in body weights during the experimental period. In addition, no differences were found between the control and treated groups in clinical sign, hematology, serum biochemical, and histopathological analysis. Conclusion: Compared with the control group, we could not detect any toxic alteration in all treated groups. These studies indicate that the acute toxicity of benzo[a]pyrene is relatively low.

• 한국안전학회지
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• 제38권6호
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• pp.60-71
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• 2023

The purpose of this study is to propose a quantitative toxicity endpoint distance suitable for the initial response of firefighters by comparing and analyzing the commonly applied toxic level of concern (T-LOC), specifically emergency response planning guidelines (ERPG), acute exposure guideline levels (AEGL), and immediately dangerous to life or health (IDLH). This is to protect the fire brigade, which responds to toxic chemical accidents first during the golden time. Using areal locations of hazardous atmospheres, a damage prediction program, the amount of leakage for both acidic and basic substances, along with the endpoint distance, were analyzed for alternative accident and worst-case accident scenarios. The results showed that the toxicity endpoint distance, serving as a compromise between Level-3 and Level-2 of T-LOC, was longer than ERPG-3 and shorter than ERPG-2 with IDLH, while its values were analyzed in the order of ERPG-2, AEGL-2, IDLH, AEGL-3, and ERPG-3. It is suggested that the application of IDLH in an emergency (red card) and ERPG-2 endpoint distance in a non-emergency (non-red card) can be utilized for the initial response of the fire brigade.

• 한국환경보건학회지
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• 제45권2호
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• pp.192-202
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• 2019

Objectives: According to the central limit theorem, the samples in population might be considered to follow normal distribution if a large number of samples are available. Once we assume that toxicity dataset follow normal distribution, we can treat and process data statistically to calculate genus or species mean value with standard deviation. However, little is known and only limited studies are conducted to investigate whether toxicity dataset follows normal distribution or not. Therefore, the purpose of study is to evaluate the generally accepted normality hypothesis of aquatic toxicity dataset Methods: We selected the 8 chemicals, which consist of 4 organic and 4 inorganic chemical compounds considering data availability for the development of species sensitivity distribution. Toxicity data were collected at the US EPA ECOTOX Knowledgebase by simple search with target chemicals. Toxicity data were re-arranged to a proper format based on the endpoint and test duration, where we conducted normality test according to the Shapiro-Wilk test. Also we investigated the degree of normality by simple log transformation of toxicity data Results: Despite of the central limit theorem, only one large dataset (n>25) follow normal distribution out of 25 large dataset. By log transforming, more 7 large dataset show normality. As a result of normality test on small dataset (n<25), log transformation of toxicity value generally increases normality. Both organic and inorganic chemicals show normality growth for 26 species and 30 species, respectively. Those 56 species shows normality growth by log transformation in the taxonomic groups such as amphibian (1), crustacean (21), fish (22), insect (5), rotifer (2), and worm (5). In contrast, mollusca shows normality decrease at 1 species out of 23 that originally show normality. Conclusions: The normality of large toxicity dataset was not always satisfactory to the central limit theorem. Normality of those data could be improved through log transformation. Therefore, care should be taken when using toxicity data to induce, for example, mean value for risk assessment.

• Toxicological Research
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• 제18권1호
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• pp.31-41
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• 2002

The present study was conducted to investigate the potential subacute toxicity of plant sterol esters by a 4-week repeated oral dose in Sprague-Dawley rats. The test article was administered once daily by gavage to rats at dose levels of 0, 1000, 3000, and 9000 mg/kg/day for 4 weeks. During the test period, clinical sign, mortality, body weights, food and water consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross finding, organ weight, and histopathology were evaluated. A reduction in the body weight was observed in females of the 9000 mg/kg group on day 27 after the initiation of treatment, but not in males of the group. There were no treatment-related effects on mortality, clinical sign, food and water consumption, ophthalmoscopy, urinarlysis, hematology, serum biochemistry, necropsy findings, organ weights, and histopathology in any treatment group. Based on these results, it was concluded that the 4-week repeated oral dose of plant sterol esters resulted in suppressed body weight in female rats at a dose level of 9000 mg/kg/day. In the condition of this study, target organ was not observed and the no-observed-adverse-effect level (NOAEL) was considered to be 9000 mg/kg/day for males and 5000 mg/kg/day for females.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.131-143
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• 2010

We performed the tests of acute and subchronic inhalation toxicity of methyl formate, which has limited toxicological data in spite of its widespread use and enhanced hazard consequent on its high volatility. The median lethal concentration ($LC_{50}$) was evaluated to be above 5,000ppm(12.27 mg/L). In the test with subchronic inhalation, there are no deaths, but with reduction of body weight, food intake, organ weight by exposure to 400 (0.98 mg/L) and 1,600 (3.92 mg/L) ppm, dose-dependently. There were statistical differences in some hematological and blood biochemical parameters as compared to control (e.g. neutrophile and lymphocyte in the 1,600 ppm group, calcium and A/G in 1,600 ppm group). Methyl formate under the exposure of 1,600 ppm showed the respiratory findings with nasal, it was confirmed that the chemical has respiratory hazard with 1,600 ppm inhalation exposure, induces nasal epithelial atrophy, olfactory cell degeneration/regeneration and the contraction of olfactory cells, etc. According to the notification with Ministry of Labor (No. 2009-68) for classification, labeling and MSDS of chemicals, it is suggested for methyl formate to be classified as category 4 in acute (10.0$4\leq20.0$ mg/L), category 2 (0.2$\leq$1.0 mg/L/6h, 90 days) in specific target organ-repeated exposure.