• Journal of the Korean Wood Science and Technology
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• v.52 no.1
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• pp.31-46
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• 2024

Subterranean termite attacks on cajuput (Melaleuca cajuputi) seedling roots were widespread in several of Java's Perum Perhutani Forest Management Units. This attack was suspected to be related to the chemical components of the cajunput seedling roots. This study was conducted to determine the bioactivity of cajuput seedling root extract as an attractant for the subterranean termite Coptotermes curvignathus Holmgren (Isoptera: Rhinotermitidae). The extraction process was performed according to ASTM D1108-96, and the extract was characterized using gas chromatography-mass spectrometry (GC-MS). Bioactivity testing of the extracts was carried out using attractiveness and no-choice feeding bioassays. The results showed that the average root extraction yield from cajunput seedlings was 4.94%. The attractiveness of the extract solutions at concentrations of 0.50%, 0.75%, and 1.00% were 45.33%, 62.00%, and 74.67%, respectively. The mortality rate of C. curvignathus termites ranged from 9.63% to 24.44%. Cajuput seedling root extract's lethal concentration 50 was 2.45% (non-toxic). GC-MS analysis showed that the extract contained linoleic acid, which has the potential to attract insects.

• Advances in Traditional Medicine
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• v.8 no.2
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• pp.192-195
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• 2008

The effect of aqueous and alcoholic extract of roots of Berberis aristata was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of cattle filarial parasite Setaria cervi and on the survival of microfilariae. Only aqueous extract could inhibit the spontaneous movements of S. cervi, characterized by initial stimulation followed by reversible paralysis. The concentration required to produce similar effect on n.m complex was less as compared to the w.w. The lethal concentration 50 and lethal concentration 90 for aqueous extract were 48 ng/ml and 65 ng/ml.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.705-711
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• 2016

In this experiment, embryos of Asian toad, Bufo gargarizans, were investigated to evaluate toxicity of chemicals along FETAX(Frog Embryo Teratogenesis Assay-Xenopus) protocol. Asian toad, Bufo gargarizans, embryos incubated and investigation of Zn and Benomyl effect by probit analysis. As a result, depends on the concentrations of Zn and Benomyl, mortality and malformation rates were increases and larval body length were decreased. The teratogenic concentration($EC_{50}$) of Zn and Benomyl were 2.3, $1.0mg/{\ell}$, respectively and the embryo lethal concentration($LC_{50}$) Zn and Benomyl were 10.3, 6.9, respectively. The teratogenic index(TI) were 4.4 in Zn and 6.7 in Benomyl, thus showed teratogenicity in embryonic development of B. gargarizans. These results reveal that Zn and Benomyl in this experiment suppressed the development of embryos at relatively low concentration. Much of B. gargarizans embryos can be secured, and easy to incubate. In addition, mortality, malformation ratios, malformation patterns and growth rates are similar to the results from the other assay systems. Therefore, the B. gargarizans embryo teratogenesis assay system could be a useful tool to evaluate toxicity of pollutants in environment.

• Advances in Traditional Medicine
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• v.5 no.3
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• pp.240-245
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• 2005

The effect of aqueous and alcoholic extract of seeds of Nigella sativa (N. sativa) was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of Setaria cervi (S. cervi). Both the extracts caused inhibition of spontaneous movements of the w.w and n.m complex characterized by initial stimulation followed by irreversible paralysis, with the exception that aqueous extract produced a partially reversible paralysis of w.w preparation. Lesser concentration of both the extracts was required to inhibit the movements of n.m complex than the w.w. Suggesting a cuticular permeability barrier. The lethal concentration $50\;(LC_{50})$ and lethal concentration $90\;(LC_{90})$ were 30 and 55 ng/ml for aqueous and 45 and 60 ng/ml for alcoholic extracts respectively.

• The Korean Journal of Pesticide Science
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• v.13 no.2
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• pp.87-97
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• 2009

Octachlorostyrene (OCS) is a persistant and bioaccumulative toxic subtance (PBTs). In this study, acute toxicity tests on algae, daphnia and fish for octachlorostyrene and its isomers were done to determine effective concentration ($EC_{50}$), Lethal concentration ($LC_{50}$), no observed effect concentration (NOEC) or lowest observed effect concentration (LOEC). As a result, NOEC on algae growth inhibition test for octacholorostyrene and 2-, 3-chlorostyrene was determined as $0.50\;mg\;L^{-1}$, and NOEC for 4-chlorostyrene was determined as $0.13\;mg\;L^{-1}$. NOEC on daphnia, acute immobilisation test for octachlorostyrene and 2-, 3-chlorostyrene was determined as $5.00\;mg\;L^{-1}$ and $EC_{50}$ for 4-chlorostyrene was determined as $2.128\;mg\;L^{-1}$. NOEC on Oryzias Latipes, acute toxicity test for octachlorostyrene was determined as $80.0\;mg\;L^{-1}$ and NOEC for 2-, 3-chlorostyrene was determined as $60.0\;mg\;L^{-1}$. $LC_{50}$ for 4-chlorostyrene was determined as $39.0\;mg\;L^{-1}$ (48h) and $22.6\;mg\;L^{-1}$ (96h).

• Journal of the Korean Institute of Gas
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• v.17 no.4
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• pp.18-25
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• 2013

It may occur health hazards or death by suffocation or acute poisoning in case of oxygen deficiency in ambient or exposure to harmful gas. As a part of accident prevention, we studied the change of activity and lethal dose by changing the concentration of several hazardous gas with inhalation exposure chamber and laboratory animals. We investigated the lethality and motility change during either the 4 hrs whole body exposure to oxygen, nitrogen, toluene, $H_2S$, CO and 48 recovery. As results, it is estimated that 5% oxygen concentration as lethal concentration and 5.5% as $LC_{50}$ (rat, 4 hrs) with statistics for dose-response. The results of lethality in oxygen deficient condition (approximately 6%), the lethalities were 40%, 20% with 20 ppm $H_2S$, 600 ppm CO respectively, and was not increased the lethality with 8% CO. Thus, it was confirmed that the $H_2S$, CO had influence to lethal dose, while toluene had low fluence.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.113-117
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• 1979

The short-term acute toxicities of mercury, cadmium and copper for the clam, Meretrix lusoria were determined from 28 June to 15 July, 1978. In the test with mercury and copper, the rate ot mucus excretion increased gradually at a higher concentration. But the clams did not excrete mucus in the solutions of cadmium and natural sea water. The rate of mucus excretion in mercury was $42.9\%$, and that in copper was $14.3\%$ in a test solution of 1mg/l. mercury was more toxic than copper. The median lethal concentration after 96 hours (96 hr-Lc 50) was 0.67mg/l in mercury, 7.04mg/l in copper and 7.10mg/l in cadmium. Consequently it was found that mercury was the most toxic substance and cadmium was the least. meanwhile, it was considered that exposure time by stimulation in a fixed concentration caused the test animals to respond.

• Fire Science and Engineering
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• v.29 no.2
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• pp.73-78
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• 2015

Fire in the risk management subject belongs to high risk disaster which accompanies personnel and materiel loss. So, management of disaster and safety is required to include fire prevention activities, fire risk prediction and investment of safety management expense. Combustion toxicity is required by gas toxicity test (KS F 2271), to minimize human damage. In this study, gas toxicity test were experimented with regard to urethane sample (Depth 5~25 mm) to obtain basic data. Fire effluent exposing to experimental animal were analyzed by FT-IR (Fourier transform infrared spectroscopy). Combustion toxicity index Lethal Fractional Effective Dose ($L_{FED}$) of ISO 13344 was calculated. According to the result of calculating Lethal Concentration 50% ($LC_{50}$) based on $L_{FED}$, $LC_{50}$ of urethane sample containing certain level of fire load is confirmed as $118{\sim}129g/m^3$. Through this study, applicability of this method was confirmed for fire risk assessment. This method can provide information to predict human damage by toxicity combustion gas for securing safety.

• Korean Journal of Environment and Ecology
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• v.34 no.3
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• pp.207-215
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• 2020

In this experiment, investigated toxicity evaluation of chemicals using Asian toad embryos, along FETAX(Frog Embryo Teratogenesis Assay-Xenopus) protocol. Asian toad, Bufo gargarizans embryo incubated and investigation of Benomyl(Germicide), Carbofuran(Insecticide) and Thiobencarb(Herbicide) effect by probit analysis. As a result, depends on the concentrations of Benomyl, Carbofuran and Thiobencarb, along mortality and malformation rates were increases and larval body length were decreased. The teratogenic concentration(EC₅₀) of Benomyl, Carbofuran and Thiobencarb were 1.03, 8.74, 4.98mg/ℓ, respectively. And when exposed to Benomyl, larvae responded most sensitively to malformations. Embryo lethal concentration (LC₅₀) Benomyl, Carbofuran and Thiobencarb were 7.26, 560.72, 16.87mg/ℓ, respectively. And Benomyl were at the lowest concentration of lethal the embryos. The teratogenic index(TI) were 7.05 in Benomyl, 64.16 in Carbofuran and 3.39 in Thiobencarb, thus TI values were above 1.5, which is the criterion of teratogenicity. Three of the pesticides used in this study were considered to be a teratogenic substances and Carbofuran was the most potent teratogen. And more specific researches are needed to investigate the effects of pesticides on the embryo development of toads and amphibians and their mechanism.

• Journal of fish pathology
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• v.35 no.1
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• pp.65-75
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• 2022

Mirror carp, Cyprinus carpio nudus (weight 26.2±3.1 g, length 11.8±0.5 cm) were exposed to waterborne total ammonia nitrogen (TAN) at 0, 2, 4, 8, 16, 32, 64 and 128 mg TAN/L. The lethal concentration 50 (LC₅₀) of mirror carp, C. carpio nudus exposed to waterborne ammonia was 60.38 mg TAN/L. The red blood cell (RBC) count was significantly reduced by ammonia exposure, whereas there was no significant changes in the hemoglobin concentration and hematocrit value. In the plasma components, glucose, total protein, aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were significantly increased by ammonia exposure. The results of this study suggest that the ammonia exposure to C. carpio nudus affects the survival rates, hematological parameters and plasma components as toxicity.