• Environmental Analysis Health and Toxicology
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• v.18 no.1
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• pp.21-25
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• 2003

카바메이트계 농약인 카보푸란은 어류에 대한 독성이 매우 높으며, 낮은 농도에서 어류의 척추기형이나 행동이상을 유발한다. 이러한 카보푸란의 독성기전을 밝히기 위한 일환으로 신경물질대사와 관련이 깊은 acetylcholine esterase(AChE)와 monoamine oxidase(MAO)에 미치는 농약의 효과를 송사리(Oryzias latipes; Medaka fish)를 이용하여 평가하였다. Medaka fish에 대한 카보푸란의 반수치사농도(LC$_{50}$)는 2.5 ppm이었으며, 1 ppb 카보푸란에 24시간 노출된 경우, AChE 효소활성이 머리와 몸통부위에서 각각 30, 20%씩 감소되었다. 한편, MAO 효소활성은 카보푸란의 농도가 증가함에 따라 머리부위에서는 감소한 반면, 몸통부위에서는 증가하는 경향을 보였다. 특히 카보푸란의 농도가 1 ppb에서도 송사리의 MAO 효소활성이 영향을 받는 것으로 나타나, 카보푸란에 의한 송사리의 행동이상은 AChE 활성 뿐 아니라 MAO활성의 변화에 의한 복합적인 효과일 가능성이 높다.

• The Korean Journal of Mycology
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• v.18 no.1
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• pp.13-19
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• 1990

Four isolates of Fusarium sporotrichioides obtained from the corn producing area were tested for their toxicities by feeding the crude cultures to rats. Three out of four isolates were highly toxic and killed all rats within 3-4 days after feeding. The chemical analyses of toxic cultures by thin layer chromatography and gas chromatography-mass spectrometry revealed that two isolates from Jeongsun district produced T-2 toxin and its related trichothecenes. This is the first report that F. sporotrichioides isolates produce T-2 toxin in Korea.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.166-171
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• 1984

The present studies were conducted to investigate the relative toxicity of several insecticides to the rice insect pests and the predatious spider, Pirate subpiraticus. In laboratory test by topical application, BPMC and MIPC for the plant and leafhoppers were toxic to Nilaparvata lugens, but less toxic to Pirata subpiraticus. Other carbamate insecticides such as carbaryl, carbofuran, and MTMC showed highly toxic effect on P. subpiraticus as well as N. lugens. No organophosphates showed selective toxicity to P. subpiraticus. Thiocyclam, effective to Chilo suppressalis and Sesamia inferens, had highly good selective toxicity to P. subpiraticus. In case of insecticides for Nephotettix cincticeps, BPMC only had a little selective toxicity between N. cincticeps and P. subpiraticus. Organophosphate insecticides which had been reported to induce chemical resistance to N. cincticeps showed high $LD_{50}$ value to N. cincticeps. In pot trials, dust formulation was more toxic to P. subpiraticus than emulsifiable concentrate. It was more toxic to P. subpiraticus to increase number. of insecticide application.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.280-284
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• 2006

The toxic effects of 14 commercially available fungicides on the earthworm, Eisenia fetida (Savigny), were evaluated using surface sprayed soil, immersion and contact filter tests. At recommended dose, the earthworm mortality is 4% on mancozeb, carbendazim, propineb and captan in the surface sprayed soil test, 4% on mancozeb, 6% on propineb and 10% on captan in the immersion test, and no effect on all used chemicals in contact filter test.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.496-504
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• 1997

This study was carried out to estimate toxic effects of phenol on survival and metabolism of the abalone juvenile, Haliotis discus hannai. The experiment was conducted by renewal bioassay procedure with different salinities at $20^{\circ}C$. The $LC_{50}$ of the juvenile exposed to phenol in the range of 0.5 and $100mg/\ell\;was\;34.3\~6.5mg/\ell\;at\;2.4\%_{\circ}\;and\;52.2\~9.3m/\ell\;at\;32\%_{\circ}$ salinity with exposure time from 24 hours to 96 hours. $LT_{50}$ was remarkablely reduced with increase of phenol conentration and decrease of salinity. Lethal toxicity or phenol was higher at low salinity than at high salinity. Therefore, salinity is likely to be one of factor to increase phenol toxicity. The oxygen consumption of the juvenile was reduced with increase of phenol concentration and with decrease of salinity. In spite of phenol toxicity, the oxygen consumption of the juvenile exposed to phenol of low concentration was high and similar as compared with that of control group. Survival rates of the abalone kept in phenol-free sea water after exposure to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours were reduced with decrease of salinity. Durations required to recover the normal metabolic rate of the juvenile, which was exposed to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours, were made longer with increasing phenol concentration. In the case of the juvenile exposed to sublethal concentration of phenol for 15 days, it were elongated as compared with that of the abalone exposed to phenol concentration caused acute toxicity. The result of this experiment indicated that relatively low concentration of phenol can impact on the abalone juvenile in marine ecosystem.

• Korean Journal of Environmental Biology
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• v.18 no.4
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• pp.377-385
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• 2000

This study was carried out to investigate the ecotoxicological response on Gammarus sobaegensis Ueno with acid stress. Mean value of $LT_{50}$ (lethal time 50%) under pH 3 condition as acute ecotoxicity test was observed to be 0.271 ($\pm$0.146) day. And 0.812 ($\pm$0.377) day under pH 4, respectively. Mean value of $LT_{50}$ under pH 3 and 5 were 6.313 ($\pm$0.828), and 9.475 ($\pm$4.881) day, respectively. Variance in chronic ecotoxicity test pH (F ratio: 11.240, P< 0.0005) and times (F ratio: 2.916, P< 0.0005) as single factor were revealed to be the major factor for determining LT$_{50}$ with acid depression. The variation of secondary gill surface with acid stress to be certain that wrinkle phenomenon. Being weak tolerance of G. sobaegensis against the acid stress, it shows the possibility to be examined as an aquatic toxicity test organism.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.39-44
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• 2009

This study was conducted to evaluate the actual risk of fipronil on worker honey bees (Apis mellifera L.) through acute contact toxicity test, acute oral toxicity test, toxicity of residues on foliage test, and small scale field test. The $48h-LD_{50s}$ of fipronil SC on honeybee were $0.005{\mu}g$ a.i./bee in acute contact toxicity test and $0.004{\mu}g$ a.i./bee in acute oral toxicity test, respectively. In toxicity of residues on foliage test, fipronil showed over 90% of mortality during 28days after treatment at recommended application rate. The $DT_{50}$ of dislodgeable foliar residue was 9 days. Finally, In small scale field test, fipronil showed similar toxicity in the residues on foliage test. It was concluded that fipronil has very high acute toxicity and long residual toxicity to honeybee. Therefore, fipronil is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area. To protect honeybee and wild pollinators from outdoor use of fipronil, ultimately it should need to limit for only indoor use to prevent pollinators from unintentionally exposure of fipronil.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.124-133
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• 1996

A herbivorous copepod, Tigriopus japonicus, was tested to study its acute and chronic responses to Cd tonicity. Under $20^{\circ}C,\;96hr-LC_{50}$ of T. japonicus in medium with $32\%_{\circ},\;26\%_{\circ},\;and\;18\%_{\circ}$ salinity were 11.1 ppm, 13.7 ppm, and 9.7 ppm, respectively. The $96hr-LC_{50}$ in medium with $32\%_{\circ},\;26\%_{\circ},\;and\;18\%_{\circ}$ salinity increased to 21.6 ppm, 15.0 ppm, and 11,0 ppm, respectively under $10^{\circ}C$ condition. Oxygen consumption rates during 96hrs exposure to Cd toxicity decreased more sharply at $20^{\circ}C$ than those at $10^{\circ}C$. Survival rate and $250dys-LC_{50}$ of T. japonicus in medium with $32\%_{\circ}$ salinity, in concentration of Cd 4 ppm were $5\%$ and 0.05 ppm, respectively under $10^{\circ}C$, and $0\%$ and 0.20 ppm under $20^{\circ}C$. It was that the copepod selectively feed on Skeletonema costatum, Nitzschia pungens, N. seriata, and Rhizosolenia hebetata f. semispina.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.694-700
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• 2018

To investigate the effect of heavy metals (Cu, Cd, Hg, Pb, Zn) on mosquito Culex pipiens, 50% lethal concentration ($LC_{50}$) concentration, total lipid content, lipid content composition, and total protein content were measured. The results showed that the Hg $LC_{50}$ was $0.45mg\;kg^{-1}$ and the Hg toxicity was higher than the other metals. The results also showed that cadmium (Cd) significantly retarded the growth of mosquito larvae among the tested heavy metals. Six types of lipid bands were isolated from mosquito samples exposed to heavy metals, and five of them were identified (phospholipid, cholesterol, fatty acid, triglyceride, and cholesterol ester). The total lipid content of all treatments decreased compared to the control. In addition, the protein content of the control group ($0.51mg\;ind.^{-1}$) was higher than that of the treated group, and the protein content of the larvae treated with Hg and Cd was very low. In conclusion, heavy metals not only lower the survival rate of mosquitoes, but also affect the protein content and lipids in the mosquito's body, thereby causing growth inhibition. These results indicate that heavy metal contamination will affect the size of mosquito population by inhibiting the survival and growth of mosquitoes, and it is expected that it can be used to measure the degree of contamination using mosquito through subsequent studies.

• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.7-16
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• 2012

Combustion Toxic Effects among several factors of risk encountered during fire are important in the evacuation and final survival, and they are broader and fatal than the direct damages caused by flame. Most studies on fire toxicity until the present are limited to fatality, mainly deaths by fire through pathological research. In this study, it is conducted as a fundamental experiment to address 3 principles of animal experiment and to provide an alternative test to animal testing that is regulated by national building codes and it was conducted through approval by the animal testing ethics committee. Hence, in this study average time of activity stop was measured after directly inhaling toxic gases (HCN) to laboratory animals (mice) through gas toxicity test (KS F 2271) for major asphyxiating gases(HCN) which are produced during fire combustion. effects of Combustion toxic gases on body were quantitatively analyzed through changes in internal organs and hematological analysis, and electrophoresis of a single cell of these laboratory animals. Biological conclusion of combustion toxicology is drawn through approaches (pathological examination, blood test, blood biochemical test, electrophoresis analysis of single cell) which could not confirmed in existing gas toxicity test.