• Journal of Aquaculture
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• v.11 no.4
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• pp.429-435
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• 1998

This study compared acute ammonia toxicity in juvenile rockfish and red sea bream. Oxygen concentration affected ammonia toxicity to aquatic animals. Without aeration, the 96-hr $LC_50$ values of $NH_4^+$and un-ionhized ammonia for juvenil rockfish(3.6g, 6.6cm) were 2.61 and 0.09 mg/l, respectively. The 3-hr $LC_50$ values of $NH_4^+$ for the size of 1.9g (5.2cm) and 3.6g (6.6cm) rockfish, and 1.0g (3.8cm) and 2.0g (5.0cm) red sea bream without aeration were 3.96, 3.94, 4.35 and 3.75 mg/l, respectively. When oxygen level was low, larger fish were more susceptible to ammonia toxicity than smaller one because of stress resulted from low oxygen. However, with aeration, the 96-hr $LC_50$ values of $NH_4^+$ for the size of 1.2g (3.9cm) and 2.3g (5.1cm) red sea bream with aeration were 3.84 and 3.90mg/l, respectively. The 6-hr $LC_50$values of $NH_4^+$ for the size of 3.1g (5.9cm) and 6.2g (7.0cm) rockfish with aeration were 3.83 and 3.94 mg/l, respectively. When oxygen level was high, larger rockfish and red sea bream were less susceptible to ammonia toxicity than smaller ones. The 6 hr-or 96 hr-$LC_50$ values of $NH_4^+$for rockfish with reduced ammonia toxicity. In comparing 96 hr-$LC_50$ values of $NH_4^+$ and un-ionized ammonia for juvenil rockfish with those for juvenil red sea bream, the values for rockfish were lower than for red sea bream. This indicates that juvenile rockfish is more susceptible to ammonia toxicity than juvenile red sea bream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.599-607
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• 1986

Acute toxicity of crude oil (WSF) on the mortality and respiration rates of Neomysis awatschensis was examined. This experiment was conducted by static and short-term bioassay procedure. In lethal test, the test animals were exposured to 8 different concentrations to determine $LC_{50}$ value (median lethal concentration). The concentrations of total hydrocarbon of 96-hr $LC_{50}$ value at $14^{\circ}C\;and\;20^{\circ}C$ were 1.01 ppm and 0.78 ppm, respectively. $LT_{50}$ (the median lethal time) also was determined. The $LT_{50}$ of 0.56 ppm was found within 100 hours, while the $LT_{50}$ of 5.6 ppm was 21 hours at $14^{\circ}C$. At $20^{\circ}C$, the $LT_{50}$ values of 0.56 ppm and 5.60 ppm were 95 hours and 17 hours, respectively. There was little difference between two temperature experiments. The effect of WSF on respiration rate was more sensitive than that on mortality, but no considerable difference was shown between different concentrations in this experiment. The results of these experiments indicated that relatively low concentration of dissolved crude oil fraction can impact on small crustacean in the marine ecosystem.

• Journal of Life Science
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• v.26 no.2
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• pp.204-211
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• 2016

The objective of this study was to obtain acute (single) oral dose toxicity information on Lactobacillus-fermented Araliae Continentalis Radix aqueous extracts (fACR) in female and male ICR mice, as compared with Araliae Continentalis Radix aqueous extracts (ACR). After administering a single oral dose of fACR, no treatment-related mortalities were observed within 14 days after the end of treatment up to 2,000 mg/kg, the maximum dosage for rodents of both sexes; moreover, no fACR treatment-related changes in the body and organ weights, clinical signs, necropsy, and histopathological findings were detected in this experiment. In addition, no ACR 2,000 mg/kg treatment-related mortalities, clinical signs, body and organ weights, or gross and histopathological findings were observed, as compared with equal genders of vehicle control. The results obtained in this study suggest that fACR is non-toxic in mice and is, therefore, likely to be safe for clinical use. The LD₅₀ and approximate LD in female mice and male mice, respectively, were considered after a single oral dose of fACR over 2,000 mg/kg, the maximum dosage for rodents. In addition, no specific targets or clinical signs were detected in the present study. ACR 2,000 mg/kg-treated mice also did not show any treatment-related mortalities, clinical signs, changes to body and organ weights, or gross and histopathological findings, as compared with equal genders of vehicle control.

• Journal of fish pathology
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• v.12 no.1
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• pp.32-41
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• 1999

Ozonization for rearing seawater in land-based culture system has recently been utilized for disinfection of pathogenic microorganisms and improvement of water quality. This study was conducted to examine the effects of total residual oxidants (TRO) in ozone-treated seawater on survival, blood parameters, osmolality and oxygen consumption, and gill tissue of the flounder. Paralichthys olivaceus. Experiments were carried out with the starved flounder of 12~19 cm in total length at $20^{\circ}C$. The 48-hr and 96-hr $LC_{50}$ for the flounder amounts to 26.4 ppb and 22.3 ppb, respectively. With increase of TRO concentration from 24 to 39 ppb, the values of hematocrit, hemoglobin concentration, red blood cell count and osmolality of the flounder with respect to exposure time were significantly elevated, however, the oxygen consumption rates decreased. In the case of the fish exposed to 13 ppb for 96 hrs, blood glucose increased with an elapse of exposure time, while survival rate was 100%. Death apparently resulted by massive destruction of gill lamellar epithelium, severe osmotic imbalance and the lack of oxygen uptake. The results of this experiment indicated that to protect aquaculture organisms, the ozone-treated seawater should not contain any residual oxidants, and that relatively long-term exposure to TRO of low concentration can impact on survival and physiological conditions of the flounder.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.359-362
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• 2013

This study was performed in order to assess the risk of earthworm when the picoxystrobin was sprayed in Korean orchard. The acute toxicity ($LC_{50}$) of picoxystrobin active ingredient(99.3%) and soluble concentrate (25%) against earthworm was showed 10.93 mg/kg and 8-16 mg/kg respectively. This earth worm toxicity value means that the picoxystrobin do not show the earthworm risk in present Korean risk assessment system. However, in the test which was simulated the rainfall after spraying, all the earthworm were died in 24 hours. This result indicated that the risk assessment for the earthworm should be considered the weather condition.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.58-66
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• 2013

Among the risks which can be faced with fire, combustion toxicity is a significant influence on the survival. Fire toxicity researches have been limited generally on the lethal aspects. In this study, HF gas which can be generated from fire, and also found in general industrial site was used for analysis. Blood analysis and biochemistry analysis performed to find internal demage of experimental animals which were used for measuring average activity stopping time from Animal test(KS F2271: Gas hazard test). In addition, Using the malondialdehyde analysis, indicators of oxidative damage, we had quantitative analysis to target lymphocyte for measuring the oxidative damage caused by toxic substances.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.310-316
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• 2011

This study was performed to evaluate the contact toxicity and residual toxicity of the 26 commercially registered insecticides against cigarette beetle, Lasioderma serricorne and maize weevil, Sitophilus zeamais adult. Among 26 insecticides, seven insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate, cypermethrin, ${\alpha}$-cyhalothrin) against L. serricorne adult and five insecticides (chlorpyrifos, chlorpyrifos-methyl, fenitrothion, fenthion, phenthoate) against S. zeamais adult showed perfect mortality, $LC_{50}$ (ppm) values of those selected insecticides were appeared lowest value on ${\alpha}$-cyhalothrin (1.46) against L. serricorne adult and chlorpyrifos-methyl (0.64) against S, zeamais adult, respectively. However, chlorpyrifos-methyl still remain high toxicity until 90th days after treatment against both L. serricorne and S. zeamais adults. From above results, it will be useful information to select insecticides effective against L. serricorne and S. zeamais adults.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.49-59
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• 1986

To examine safety of Ganoderma lucidum, it was extracted with hot water (Fraction A). After the extract was dialyzed and freeze-dried, a polysaccharide fraction (Fraction B) was obtained and examined for acute and subacute toxicity. In the acute toxicity tests of Fr. A and Fr. B on mice, both agents did not show any serious and lethal effects. The results showed that 50% lethal doses were higher than 5,000 mg/kg. The experiments of oral administration of Fr. A (5,000 mg/kg) to mice for 30 days showed that there were no changes in body weight, hematological features and organ weight.

• Journal of Conservation Science
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• v.33 no.4
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• pp.255-266
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• 2017

Chemically derived pesticides have been used to prevent biological damage to domestic cultural property. However, their use is gradually being restricted due to the harmful effects on the human body and environment. Therefore, there is a growing interest in the search for new antifungal biopharmaceuticals whose safety has been confirmed by toxicity evaluation through animal experiments. This paper presents methods of toxicity evaluation of natural biocides using Sprague-Dawley rats and New Zealand White (NZW) rabbits. Safety of the natural biocide extract of Asarum sieboldii was evaluated using single-dose oral and dermal toxicity tests in Sprague-Dawley rats, and eye and skin irritation tests in NZW rabbits. The extract has proven antimicrobial and insecticidal activities against wood-rotting fungi and termites. After single oral administration to rats, the $LD_{50}$ values were determined to be over 4,000 and 2,000 mg/kg for males and females, respectively. After single dermal administration to rats, the $LD_{50}$ values exceeded 10,000 mg/kg for both males and females. The extract was identified to be non-irritant to the rabbit eye, and only slightly irritant to the rabbit skin. In this study, we confirmed the safety of the A sieboldii extract through animal testing. Due to the harmfulness of humidifier disinfectants, focus is on the safety of chemical pesticides, and toxicity evaluation is suggested as the basic method for hazard evaluation.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.149-152
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• 1979

The relative toxicity of some of the insecticides which have been used for the control of paddy rice insect pests in Korea was evaluated in the laboratory with the brown planthopper (BPH) Nilaparvata lugens, and a predaceous paddy spider Pirata subpiraticus. In order of the relative toxicity (LD5O value to spider/LD50 value to BPH) were PAP (0.4), MPP(0.1), MEP(1.8), diazinon(2.8), carbofuran(7.5), NAC(11.3), BPMC(17.5), Pyridaphenthion(35.9) and MIPC(65.7). MIPC and Pyridaphenthion were considered as having the desirable selective toxicity for the spider and the BPH.