• Environmental Analysis Health and Toxicology
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• v.16 no.4
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• pp.211-221
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• 2001

The purpose of this study was to investigate the acute (4 hours) and repeated-dose (6 hours a day, 5 days a week, 4 weeks) toxic effects of 1-hexene on Sprague-Dawley (SD) rats which were treated by inhalation. The results were as follows; 1. The median lethal concentration(LC$_{50}$) was estimated 52,694 ppm (confidence limit 95％; 49,494~55,447 ppm) in acute inhalation. Abnormal clinical signs related to the 1-Hexene were not observed with the acute inhalation dose. Cross findings of necropsy revealed on evidence of specific toxicity related to the 1-hexene. II. By repeated inhalation exposure the body weight of male were more or less reduced by the dose of 2,500 ppm and 5,000 ppm compared with control group. However there were no significant variation hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-hexene were not shown. In conclusion when we exposed 1-hexene to SD rats for 4 weeks, 5 days per week, 6 hours per day, the Lowest observed effect level (LOEL) was over 2,500 ppm and Non observed effect level (NOEL) was below 500 ppm.

• Environmental Analysis Health and Toxicology
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• v.17 no.1
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• pp.81-93
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• 2002

There were no specific effects for test materials on Sprague-Dawiey (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body 1, 1-Dichloro-1-fluoroethane (used as coolant, metal cleaner and solvents) exposure (0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations. there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration . Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-1-fluoroethane inhalation was evaluated in groups with 3,000 ppm below (S.D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-1-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.339-348
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• 1996

A new composite antibiotic, SM-101 (sulbactam·metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on dams and growth, behaviour and mating performance of Fl offspring were examined. In dams, one death occurred at 1000 mg/kg. The increase in kidney weight of the 250, 500 and 1000 mg/kg group was found. In F1 offspring, both delayed incisors eruption and decreased body weight were observed in females of the 1000 mg/kg group. The increase in the weights of liver and kidney was found in males of the 1000 mg/kg group. No treatment-related abnormalities were observed in each treated group in terms of behaviour and reproductive performance. In F1/F2 fetuses, no drug-induced abnormalities occurred at all doses tested. The results show that the no effect dose level (NOEL) of SM-101 is under 250 mg/kg/day for dams and 500 mg/kg/day for F1 offspring, and over 1000 mg/kg/day for F1/F2 fetuses.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.168-168
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• 1993

신의약품의 생식독성 평가를 위해서는 타독성시험의 경우와 마찬가지로 NOEL (no observed effect level) 의 범위를 확립하는 일이 매우 중요한데, 이것은 정상치(control values), 자연발생소견 (spontaneous findings)등과 비교함으로서 가능하다. SPF 동물을 이용한 독성실험은 선진국에 비해 역사가 짧을 뿐만 아니라 아직 풍부한 기초자료가 확립되지 않아 외국의 자료들을 인용하고 있는 실정이다. 본 연구에서는 랫트를 이용한 최기형 시험결과의 효율적인 평가를 위해 생식독성 검사항목의 기초 데이타를 확립하였다. 이를 위해 화학연구소 실험동물육종실에서 입수한 SPF: Sprague- Dawley 랫트를 이용해 1989년부터 1991년까지 실시한 생식독성 시험의 대조준 데이타 (체중, 사료소비량, 장기중량, 제왕절개성적, 외표, 내부장기 및 골격검사성적, 자연분만군 시험성적 등)를 분석하였다. 요늑의 발현율, 견인력 시험결과 및 피모발생 일평이 외국의 타 연구기판 데이타와 다소 차이를 나타냈을 뿐 기타 항목들은 거의 일치하는 정상치를 보였다. 아울러 기형, 변이, 골화지연 등으로 구분되는 골격소견의 합리적인 평가를 위해 랫트 골격소견 평가기준을 정했고 최기형 시험에서 얻어지는 데이터의 통계처리 방법을 보완, 체계화하였다. 본 연구결과는 Sprague-Dawley 계통 랫트외 생물학적 정외는 물론 효율적인 생식독성 평가를 위한 소중한 기초 자료가 될 것으로 사료된다.

• Toxicological Research
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• v.11 no.1
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• pp.81-89
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• 1995

A teratogenicity study of KTC-1, a new semisynthetic rifamycin antituberculous drug, was conducted in Sprague-Dawley rats. Dosages of KTC-1 0, 7, 21, and 63 mg/kg/day were administered to darns orally gayage from day 7 to day 17 of gestation. Two-third of dams per group were subjected to cesarean section on day 21 of pregnancy for examination of their fetuses, and the remaining one-third of darns per group were allowed to deliver naturally for postnatal examination of their offspring. At 21 mg/kg/day, an increase in the skeletal variations of F1 fetuses and a decrease in the body weight of F1 offspring were seen. At 63 mg/kg/day, a loss in body weight was observed in darns. An increase in fetal death rate, a decrease in litter size and body weight, and an increase in the incidence of visceral malforrnations and skeletal variations were found in F1 fetuses. In particular, lumar rib occurred at an incidence of 31%. In addition, an increase in the dead newborns at birth and neonatal deaths during the lactation period, a loss in body weight, and a decrease in spleen weight were observed in F1 offspring. There were no signs of maternal toxicity or embryotoxicity at 7 mg/kg/day. The results suggest that the no-effect dose level(NOEL)for dams is 21 mg/kg/day, and NOELs for F1 fetuses and offspring are 7 mg/kg/day.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.19-30
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• 2014

Microcystins (MCs) produced by cyanobacteria are severe hepatotoxins for mammalian and protein phosphatase inhibitors. Irrigation water for grain and vegetables is often contaminated with cyanobacteria and microcystin during warm seasons. We assessed the effects of various concentrations (0, 0.01 to $10{\mu}gmL^{-1}$) of microcystin-LR (MC-LR) and microcystin-RR (MC-RR) exposure on Oryza sativa (rice) and Brassica oleraces var. italica (broccoli). The $EC_{50}$ of leaves and roots of rice was 0.9 and $1.1{\mu}gMC-LRmL^{-1}$, respectively. The no observed effect level (NOEL) of rice was less than $0.1{\mu}gmL^{-1}$ ($100{\mu}gL^{-1}$). The $EC_{50}$ of the stems and roots of broccoli was 8.7 and $7.2{\mu}gMC-RRmL^{-1}$, respectively. There was no difference in the germination rate of broccoli among microcystin-RR concentrations. After exposure to 0, 0.01 to $10{\mu}gmL^{-1}$ MC-RR for seven days, 14, 89 and 154 ng mg-1 (dry weight) MC-RR accumulated in B. oleracea. These $EC_{50}$ values showed that microcystin-LR and -RR affected the growth of rice and broccoli. These findings suggest that MC is carried into terrestrial ecosystems via irrigation, and that the biota of higher ecological niches can be influenced by MC through bioaccumulation. Therefore, a guideline for MC concentrations in irrigation water should be set using the NOEL.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.29-40
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• 2004

Because cleaning products are part of our everyday lives, it is essential that they should not present significant risks to health. However, many petrochemicals in most soaps and detergents can be absorbed through the scalp and skin and, over time, accumulate in the organs and tissues. This accumulation may result in brain, nerve, and liver damage. Therefore, it is interested in developing non-harmful detergent. According to Korea Research Institute of Chemical Technology, GC-100X may be non-harmful and non-corrosive alkaline ionic water (pH 12). It is composed of hydroxyl radicals and supplemented with xylitol. To evaluate influence of GC-100X on rats and beagles, GC-100X was diluted with distilled water (25%, 50%, and 100% solution respectively). Each of diluted GC-100X was daily treated per oral. In body weight analysis, urinary analysis, ophthalmological test and autopsy, we did not find any significance, but in serum biochemical analysis and hematological analysis, we found some significances in middle dose group compared with control group. These significances in serum biochemical analysis and hematological analysis may be not induced by GC-100X, because it was not found to be significant from control group in histopathological examination. Thus, it is concluded that NOEL(No Observed Effect Level) of GC-100X may be higher than all treatment doses used in this study, and GC-100X may be a non-toxic detergent.

• Korean Journal of Pharmacognosy
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• v.39 no.1
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• pp.60-67
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• 2008

The subcronic toxicity of BDR-29, a herbal preparation of Cassiae Semen, Prunellae Spica, Tribuli Fructus, and Uncariae Rhamulus et Uncus, was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance at a dose 5 mg/kg, 50 mg/kg and 500 mg/kg intragastrically for 13 weeks. No death and abnormal clinical signs were observed throughout the administration period. There were not significantly different from control group in net body weight gain, food and water consumption, organ weight, gross pathological findings, and urine analysis among the groups rats treated with different doses of the BDR-29. Hematological findings and biochemical examination revealed no evidence of specific toxicity related to BDR-29. From these results, no observation effect level (NOEL) of BDR-29 is 500 mg/kg/day under the condition employed in this study.

• Toxicological Research
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• v.14 no.4
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• pp.547-555
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• 1998

The subchronic toxicity of a combined preparation of ticlopidine and ginkgo biloba extract (EGb 761) mixed in a ratio of 10: 4 was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance at a dose of 52 mg/kg, 156 mg/kg, or 467 mg/kg intragastrically for 30 consecutive days. Control rats were treated with vehicle only. Each group consisted of 10 rats. No death or abnormal clinical signs were observed throughout the administration period. A transient decrease in body weight gain and food intake was observed in the rats treated with the high dose (467 mg/kg), which was recovered to normal in a week. There were no drug-related differences in urinalysis and hematological results. A significant increase in serum total cholesterol and total protein was observed in both sexes of the rats treated with a dose of 467 mg/kg daily, but all the other values obtained in serum chemistry appeared to be within normal range. A dose dependent increase in liver weight was observed in both male and female rats. Relative kidney weight was also increased in the high dose groups. There was no gross pathological finding at terminal sacrifice. Microscopic histopathological examination did not show any lesion in terms of correlation with administration of the test substance. The results suggest that under the conditions employed in this study no observable effect level (NOEL) of the test substance be 52 mg/kg/day.

• Toxicological Research
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• v.16 no.4
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• pp.293-301
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• 2000

Toxicity of a combined preparation of ticlopidine and ginkgo biloba extract (EGb 761) in a ratio of 10: 4 was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance intragastrically at a dose of 0 mg/kg, 17 mg/kg, 52 mg/kg or 156 mg/kg for 91 consecutive days. No death or abnormal clinical sign was observed throughout the administration period. There was no difference in body weight gain, food intake or water consumption among different dose groups. Test sub-stance-related differences were not observed in urinalysis. In hematological results mean corpuscular hemoglobin (MCH) of low and high dose male group was increased. Prothrombin time of medium and high dose female group was decreased. A significant increase in serum total cholesterol was observed in both sexes of rats treated with a daily dose of 156 mg/kg, but all the other values obtained in serum chemistry appeared to be within normal ranges. A dose dependent increase in the relative liver and kidney weights was observed in both male and female rats. There were no gross pathological findings at terminal sacrifice. Microscopic histopathological examination did not show any lesion associated with administration of the test substance. The results suggest that under the conditions employed in this study no observable effect level (NOEL) of the test substance be greater than 17 mg/kg/day, but less than 52 mg/kg/day.