• Toxicological Research
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• 제17권
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• pp.25-35
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• 2001

In 1990, Tolerable Daily Intake (TDI) of 10 pg TCDD/kg/day for dioxins based on carcinogenicity and reproductive toxicity was determined by WHO/EURO, that resulted in the establishment of TDIs in other countries. In Japan, Ministry of Health and Welfare and Environment Agency, respectively established the TDI of 10 pg TCDD/kg/day and Health Risk Assessment Index of 5 pg TCDD/kg/day in 1996. Accumulation of new scientific data, especially by molecular toxicology since 1990, resulted in the reevaluation of TDI by WHO-ECEH and IPCS in May, 1998. At this meeting, it was stressed that \circled1 toxic effects of dioxin is mediated through Ah-receptor in both animals and humans, \circled2 use of ebody burdeni concept is better than the use of traditional NOAEL/UF approach, \circled3 inclusion of coplanar PCBs in the TDI by the use of new WHO-TEF. LOAELs (0.16~200 ng TCDD/kg/day) obtained from reproductive toxicity and immunotoxicity in rats, and neurobehavioral toxicity and induction of endometriosis in rhesus monkeys are calculated to be the body burden of 10~50 ng TCDD/kg that is 14~37 pg TEQ/kg/day as human daily intake. Finally TDI of 1~4 pg TEQ/kg/day was established by applying the UF of 10. In Japan, reproductive toxicity and immunotoxicity in rats were used to obtain LOAELs (100~200 ng TCDD/kg/day). Finally TDI of 4 pg TEQ/kg/day was established in June 1999 by applying the UF of 10 to human daily intake of 43.6 pg TEQ/kg/day which corresponds to the body burden of 86 ng TCDD/kg.

• Fisheries and Aquatic Sciences
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• 제13권3호
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• pp.244-253
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• 2010

The quality of marine sediments from the industrialized coastal areas of Korea (Ulsan Bay, Masan Bay, and artificial Lake Shihwa) was investigated using a bacterial bioluminescence toxicity test. Sediment toxicity results were compared with the levels of chemical contamination (trace metals, organic wastewater markers, acid volatile sulfides, total organic carbon). Effective concentration 50% (EC50) of sediments ranged from 0.014 to 1.126 mg/mL, which is comparable to or lower than values in contaminated lakes, rivers, and marine sediments of other countries. Sediment reference index (SRI) ranged from 13 to 1044, based on the EC50 of the negative control sample. Mean average SRI values in Masan Bay and Lake Shihwa were approximately 8 and 9 times as high as that in Ulsan Bay, indicating higher sediment toxicity and greater contamination in the two former regions. Sediment toxicity were strongly associated with the concentrations of some chemicals, suggesting that this test may be useful for determining potential chemical contamination in sediments.

• BMB Reports
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• 제42권5호
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• pp.260-264
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• 2009

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) exhibits cytotoxicity towards various tumor cells in vitro and induces apoptotic necrosis in transplanted tumors in vivo. It also shows severe toxicity when used systemically for the treatment of cancer patients, hampering the development of TNF-$\alpha$ as a potential anticancer drug. In order to understand the structure-function relation of TNF-$\alpha$ with respect to receptor binding, we selected four regions on the bottom of the TNF-$\alpha$ trimer that are in close contact with the receptor and carried out mutagenesis studies and computational modeling. From the study, various TNF-$\alpha$ muteins with a high therapeutic index were identified. These results will provide a structural basis for the design of highly potent TNF-$\alpha$ for therapeutic purposes. By conjugating TNF-$\alpha$ muteins with a high therapeutic index to a fusion partner, which targets a marker of angiogenesis, it could be possible to develop TNF-$\alpha$ based anticancer drugs.

• 청정기술
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• 제3권2호
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• pp.47-56
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• 1997

환경 문제에 대한 사회적 관심이 높아지고 정부의 환경 규제도 강화되면서 환경 오염물질을 줄이기 위한 공정개선의 필요성이 대두되고 있다. 공정 개선을 위해서는 각 공정이 환경에 미치는 영향을 나타내는 정량적인 기준이 필요하다. 본 연구에서는 물질수지식으로부터 정의되는 오염 지수(Pollution Index)를 폐기물의 질량(mass), BOD, toxicity에 따라 세 가지로 구분하여 정의하였으며, 각 Pollution Index는 최적의 대안을 결정할 때 환경영향평가에 대한 정량적인 척도를 제시할 수 있으므로 비용평가와 더불어 공정 선택의 객관적인 기준이 될 수 있다. 정의된 Pollution Index를 문헌에 보고된 세제 제조 공정에 적용하여 기존의 공정과 개선된 공정에 대하여 Pollution Index를 계산하여 각 공정이 환경에 미치는 영향을 정량적인 수치로 비교하였다.

• Journal of Preventive Medicine and Public Health
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• 제25권1호
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• pp.34-43
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• 1992

To investigate the effect of hyperoxia on EKG findings and to evaluate the applicability of EKG as noninvasive monitoring index of oxygen toxicity, 38 rabbits were continuously exposed to 6 different conditions-3 hyperbaric oxygenations (HBO-2.5, 3.5 and 5ATA, 100% $O_2$), normobaric oxygenation (NBO,100% $O_2$), hyperbaric aeration (HBA-5ATA, 21% $O_2$) and normobaric aeration (NBA, 21% $O_2$)-for 120 minutes and their EKG and time to dyspnea and convulsion were recorded. Dyspnea and death were observed in exposure conditions of HBO-3.5 and HBO-5 (Positive rate of dyspnea 10%, 100%, death : 10%, 25%, respectively) only, and convulsion in 4 oxygenation groups (NBO;20%, HBO-2.5;20%, HBO-3.5;20%, HBO-5;88%). Abnormal EKG findings included arrhythmia and ST-T changes and the incidences was increasing with doses(partial pressure of oxygen). In addition to EKG change, findings observed during exposure were dyspnea and convulsion in the order of appearance and when non specific ST-T change was accepted as positive(abnormal) finding, the frequency of abnormal EKG was statistically significant(p<0.01), but when it was excluded from positive results, the frequency of EKG change was not significant(p>0.05). These results suggest that the effect of hyperoxia on heart is myocardial ischemia and arrhythmia, that oxygenation more than 3.5ATA causes myocardial damage in 120 minutes exposure, and that EKG is valuable as monitoring index of oxygen toxicity.

• Toxicological Research
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• 제14권2호
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• pp.193-203
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• 1998

The toxicity of DA-125. a new anthracycline anticancer agent, on the male reproductive system was studied in Sprague-Dawley rats. Forty male rats were rando$m\ell$y assigned to Jour groups with ten rats in each group and given single intraveneous doses of DA-125 at dose levels of 0. 12.5. 25. and 50 mg/kg body weight. On day 56 after treatment the animals were allowed to mate. and their male reproductive Junctions and organs were examined in detail. Copulated females were sacrificed on day 20 of gestation for examination of embryo-fetal development. One out of ten rats in the 50 mg/kg group died on day 12 after treatment. Clinical signs such as emaciation. sedation, anorexia. swelling. dark material around eye. alopecia. and diarrhea were observed in the 25 and/or 50 mg/kg groups. Reduction in the body weight gain. decrease in the absolute weights of testes. epididymis and seminal vesicles. and/or decrease in the number of testicular sperm heads were also found. Although histopathological changes such as atrophy of seminiferous tubules. loss or decrease of spermatogenic cells. exfoliation of spermatogenic cells. vacuolization of Sertoli cells. decrease of sperm. and/or increase of necrotic spermatogenic cells in epididymal ducts were observed. no adverse effects on the motility and morphology of epididymal sperm. copulation index. fertility index. and embryo-fetal development were detected in the 25 and 50 mg/kg groups. There were no evidences of male reproductive toxicity in the 12.5 mg/kg group. These results show that single intravenouse doses of DA-125 produce significant dose-related testicular atrophy. histopathological changes. and oligozoospermia in rats and $LD_{10}$ for DA-125 appears to be 50 mg/kg body weight.

• 한국안전학회지
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• 제28권4호
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• pp.48-52
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• 2013

This study was carried out, using toxicity test apparatus, to analyze toxic gases of heat insulation material and adhesives of composite panels used for the architectural surface material when a fire occurs. The findings of this study show that CO, $CO_2$, HCOH, $CH_2CHCN$ and $NO_x$ were detected from styrofoam, reinforced styrofoam, polyurethane foam and glass fiber, but in the case of the polyurethane foam, HCl and HCN were detected as well. All the architectural adhesives released CO, $CO_2$ and $NO_x$, but HCHO was only detected from the adhesives for styrofoam, wood, tile, windows and doors; $CH_2CHCN$ was only from those for wood and stone; $C_6H_5OH$ was only from those for wood. The toxicity index was also measured for architectural surface material and adhesives. Polyurethane foam showed the highest index, 11.7, and glass fiber was followed as 6.8. Reinforced styrofoam showed 5.7 and styrofoam revealed the least 4.9. In the case of architectural adhesives, the highest ranking was those for stone 7.4, windows and doors 6.1, wood 5.3, tile 3.8, and styrofoam 3.7 were followed, respectively.

• 한국수산과학회지
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• 제34권3호
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• pp.173-178
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• 2001

저분자 alginate인 HAG-10, HAG-50, HAG-100 및 alginate를 랫드에 35일간 섭취시켰을 때, 혈청중의 지질성분과 동맥경화지수의 측정으로 특성이 가장 좋은 저분자 alginate인 HAG-50의 안전성을 확보하기 위해 랫드에 경구급성독성실험을 실시하였다. 혈청중 total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides 및 phospholipid 함량과 동맥경화지수는$5\%$ 와 $10\%$HAG-50에서 모두 유의적으로 뚜렷히 감소하여 지질대사 개선효과를 나타내었다. HAG-50의 경구급성독성실험을 검토한 결과, 투여할 수 있는 최고 용량인 랫드 체중 kg당 5.0g의 용량에서도 암$\cdot$수 모두 일반상태의 이상 반응과 폐사 및 병리$\cdot$조직학적 이상을 나타내는 예는 전혀 관찰되지 않아서 $LD_{50}$치의 산출이 불가능하였으므로 HAG-50은 아주 안전한 제재임이 검증되었다. 이상의 결과를 종합해 볼 때, 평균분자량 50,000 정도의 저분자 alginate인 HAG-50이 가장 우수한 지질대사 개선효과의 기능적 특성을 발휘하였으며, 경구급성독성실험 에서도 독성이 전혀 없었고, alginate가 가지고 있는 고유의 생리적 기능을 유지 향상시키면서 이용에 제한이 되고 있는 점성을 줄이고 용해도를 높혀서 alginate의 이용성을 높일 수 있는 새로운 형태의 식품소재라고 사료된다.

• 청정기술
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• 제21권1호
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• pp.39-44
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• 2015

본 연구에서는 다섯 종의 씨앗(춘채, 아욱, 양배추, 배추, 당근)을 이용하여 금속산화물 나노입자(CuO, NiO, Fe₂O₃, Co₃O₄, TiO₂, ZnO)들이 씨앗발아와 발아지수에 미치는 영향을 조사하였다. CuO, ZnO, NiO 나노입자는 씨앗 활성에 뚜렷한 독성 영향을 나타내었으며, 나노입자종류에 따라 상이한 민감도를 나타내었다. 각 나노입자에 대한 독성순서(EC₅₀ 범위)는 다음과 같다: CuO 6~27 mg/L > ZnO 16~86 mg/L > NiO 48~112 mg/L. 나머지 조사 대상 나노입자인 Co₃O₄, TiO₂, Fe₂O₃은 최대 1,000 mg/L 높은 농도 노출에도 뚜렷한 영향을 나타내지 않았다. 씨앗별 상이한 민감도를 나타내었으며, 가장 민감한 종인 아욱의 씨앗발아 EC₅₀은 CuO 5.5 mg/L ZnO 16.4 mg/L, NiO 53.4 mg/L로 조사되었다. 씨앗별 나노입자에 대한 독성 영향은 CuO > ZnO > NiO > Fe₂O₃ ≈ Co₃O₄ ≈ TiO₂ 나타났으나, 당근씨앗은 NiO [EC₅₀ 80.4(71.41~90.54) mg/L]와 ZnO [EC₅₀ 85.8(69.31~106.29) mg/L]가 유사한 독성을 나타내었다.

• Toxicological Research
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• 제23권4호
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• pp.391-403
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• 2007

The study was conducted to assess the repeated dose and reproduction and developmental toxicities of acetanilide, an intermediate for drug production, as a part of OECD Screening Information Data Set (SIDS) program. The test agent was administered by gavage at dose levels of 0, 22, 67, 200 and 600 mg/kg to Sprague-Dawley rats (12/group/sex) during pre-mating and mating period for males(up to 30 days) and females and pregnancy and early lactation period for females (up to 39-50 days). At 22 mg/kg, decreases in HGB, HCT (males) and MCHC (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow (both sexes) were observed. At 67 mg/kg, salivation (males), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC (males), increases in MCV (males) and spleen weight (males), hyperplasia of spleen red pulp and femur bone marrow (both sexes) were observed. At 200 mg/kg, decreases in locomotor activity and salivation (both sexes), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and increases in MCV, MCH, BUN, T-BIL (males), enlargement of spleen (both sexes), increased weight of spleen (males), hyperplasia of spleen red pulp and femur bone marrow and extramedullary hematopoiesis of liver (both sexes), atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. At 600 mg/kg, decreases in locomotor activity, cyanosis (both sexes), reddish tear, and salivation (males), mortality (4 out of 12 females), decreased body weight (females), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC and increases in WBC, MCV, MCH, reticulocyte, neutrophil, lymphocyte, monocyte, AST, ALT, BUN, T-BIL, ALB, Ca and A/G ratio (males), enlargement of spleen, increased weights of spleen (both sexes), liver (males), kidney and ovary, decreased weights of thymus (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow and extramedullary hematopoiesis of liver (both sexes), and atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. Regarding the reproduction and development toxicities, there were no treatment-related changes in precoital time, mating index, fertility index and pregnancy index at all doses tested. At 22 and 67 mg/kg, there were no adverse effects on all the parameters observed. At 200 mg/ kg, decreased body weight of pups (day 4 p.p.) were observed. At 600 mg/kg, decreased body weight of pups (day 0 and 4 p.p.) and viability index (day 4 p.p.), increased incidence of newborns dead or with abnormal clinical signs were observed. The results suggest that the NOAELs for general toxicity are < 22 mg/kg, LOAELs are 22 mg/kg and the NOAELs for reproductive toxicity are 67 mg/kg.