• Toxicological Research
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• 제19권2호
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• pp.123-131
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• 2003

This study was carried out to assess the combined repeated dose, reproduction and developmental toxicities of benzoyl peroxide for OECD SIDS (Screening Information Data Set) program. Male and female Sprague-Dawley rats were exposed to benzoyl peroxide at dose levels of 0, 250, 500 and 1,000 mg/kg/day for 29 days for males and for 41-51 days for females. No deaths were found in all animals including control group during exposure period. No hematological effects attributable to benzoyl peroxide were observed in all treated groups. Significant decrease in the weight of testes and epididymis were observed in males at 1,000 mg/kg/day. In females at 1,000 mg/kg/day, slight histopathological effects in uterus such as epithelial vacuolation or hyperplasia were observed. No treatment-related changes in precoital time and rate of copulation, fertility and gestation period were noted in all treated groups. There was no evidence of teratogenic effect of benzoyl peroxide, but body weight of pups at 1,000 mg/kg/day was significantly decreased. NOAEL for combined repeated dose and reproduction/developmental toxicity was 500 mg/kg/day.

• 한국환경보건학회지
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• 제28권4호
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• pp.17-22
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• 2002

In crustaceans, as in other arthropods, the molt cycle and the physiological process of growth are controlled by molting hormones (MH) which are steroid hormones, the ecdysteroids. Ecdysteroids are major arthropod hormones which control both development (embryonic and larval molts, metamorphosis) and reproduction. The purpose of the present study was to evaluate both fenarimol and methoprene for embryotoxicity to daphnids. The embryotoxicity associated with each compound was assessed to discern whether the embryotoxicity of methoprene might be due to ecdysone agonist and the ecdysone antagonistic effects of fenarimol on Daphnia embryo. Exposure of daphnids for three weeks to 50 M methoprene resulted in a significantly high incidence of offspring that exhibited general toxicity. This exposure concentration had significant effects on the overall number of embryo death. However, exposure to 3 or 1 $\mu$M fenarimol were no significant effects on the embryo toxicity. The incidence of both of these toxicity increased with methoprene exposure. This observation suggest that methoprene showed embryonic general toxicity during embryo development, while, only fenarimol showed weak general toxicity with early stages of embryonic development.

• 한국임상약학회지
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• 제11권2호
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• pp.68-77
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• 2001

Herbal medicines have been used since ancient times as medicines to treat and relieve the symptoms of many different human diseases. However, so far, relatively few herbal medicines have been evaluated scientifically to prove their safety, potential benefits and effectiveness. This study was conducted to provide the groundwork for improving the current registration regulations for herbal medicines in distinction from synthetic medicines. The study was performed based on the literature research and individual interviews with 5 experts who had extensive experience in registration of herbal medicines. When compared with synthetic drugs, herbal medicines exhibit some marked differences, namely the active principles are frequently unknown, standardization, stability and quality control are not easy, they are usually mixtures of complex compounds. Second, the current regulations for herbal medicines are reviewed by comparison of foreign regulation systems like the one in China. The regulation requirements of herbal medicine in China are in distinction from synthetic drugs. The authors conclude that new registration requirements for the herbal medicines should be changed as follows; the toxicity and efficacy data should be submitted as mixed herbal preparation and the documents and other research on the reproduction and generation toxicity need to be shown for the proof of reproduction and generation toxicity, if needed.

• 한국산업보건학회지
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• 제22권2호
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• pp.164-173
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• 2012

Objectives: Epichlorohydrin is a material that has been predicted to have high volatility and strong toxicity and is used normally in working area. Therefore, the hazardous and dangerous level and the foreign management system about epichlorohydrin should be invested at home and abroad and through hazard assessment for occupational environment measurement and exposure status of industrial workers in domestic working area. Methods: To assess risk and to suggest Development and Adoption to prevent health damage of workers owing to the epichlorohydrin exposure, the hazardousness and dangerousness of epichlorohydrin and its practical examples and regulation level for domestic and abroad health impairment are researched on the base of various references. Results: The epichlorohydrin caused skin and mucus membrane irritation, respiratory paralysis, kidney and live damage under the influence of acute toxicity and in animal study, it was confirmed as a doubtful carcinogenic substance to trigger reducement of sperm number and reproduction ability, abnormal spermatogenesis, mutagen, increase of forestomach epithelium and occurrence of papilloma and so on, as well as it induced stimulus asthma and allergic contact dermatitis for exposure workers. Conclusions: Epichlorohydrin was found to occur allergic contact dermatitis, carcinogenesis doubt and reproduction toxicity and was verified as a material which would be established reinforcement of management level to care health of handlers, such as denotement dangerousness of skin absorption.

• 한국동물생명공학회지
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• 제36권1호
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• pp.2-8
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• 2021

Dimethachlor is a synthetic herbicide, belonging to the chloroacetanilide group, that inhibits the undesirable growth of weeds via the suppression of very long-chain fatty acid synthesis. Although dimethachlor has been shown to run off from agricultural fields into aquatic ecosystems, the toxicity of dimethachlor on aquatic invertebrates and vertebrates is unknown. In our study, we assessed the toxicity of dimethachlor on developing zebrafish embryos by analyzing viability, hatching ability, and phenotypic changes. Embryonic viability decreased from 48 h post-fertilization (hpf) at the highest concentration of dimethachlor. Decreased hatching ratio, shortened body length, and pathological changes in the eye, heart, and yolk sac were observed at sub-lethal concentrations. Additionally, dimethachlor increased the number of apoptotic cells and level of reactive oxygen species 120 hpf. Our results indicate that dimethachlor may act as an anti-developmental toxicant when accumulated in an aquatic environment.

• 한국동물생명공학회지
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• 제37권3호
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• pp.176-182
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• 2022

Norflurazon is widely used on agricultural lands and has a high potential to pollute water sources. However, its effects on fish have not been fully elucidated. The purpose of our study was to determine whether norflurazon adversely affects the developmental stage of zebrafish, which are frequently used as a model system to evaluate the environmental impact of pollutants. Norflurazon interfered with the hatching of zebrafish embryos and induced several sublethal deformities including body length reduction, increased yolk sac volume, and enlargement of the pericardial region. We further examined the cardiotoxicity of norflurazon in the flk1:eGFP transgenic zebrafish line. The vascular network, mainly in the brain region, was significantly disrupted in norflurazon-exposed zebrafish. In addition, due to the failure of cardiac looping, norflurazon-exposed zebrafish had an abnormal cardiac structure. These developmental abnormalities were related to the apoptotic process triggered by norflurazon. Overall, the present study demonstrated the non-target toxicity of norflurazon by analyzing the hazardous effects of norflurazon on developing zebrafish.

• 한국동물생명공학회지
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• 제37권3호
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• pp.162-168
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• 2022

Mecoprop-p, a chlorophenoxy herbicide, has been widely used since the 1980s. Due to its high water solubility, it could be detected in the aquatic environment, as it has already been detected in the surface water or groundwater in several countries. The toxicity of other chlorophenoxy herbicides has been reported; however, there are few studies on the toxicity of mecoprop-p, one of the chlorophenoxy herbicides, on aquatic organisms. Here, we investigated the toxic effects of mecoprop-p using zebrafish. After mecoprop-p exposure, we observed that the zebrafish larvae eyes did not form normally, heart edema was generated, and the body length was shortened. The number of cells undergoing apoptosis also increased in the anterior part including head, heart, and yolk sac of the mecoprop-p-treated zebrafish compared to the untreated controls. Moreover, cardiovascular structures, including the heart and aortic arches, were also malformed after exposure to mecoprop-p. Therefore, our results suggest that mecoprop-p could cause abnormal development in zebrafish larvae and there is also a high possibility that mecoprop-p would be toxic to other aquatic organisms.

• 한국환경과학회지
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• 제16권4호
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• pp.425-432
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• 2007

The water flea has been used as a test organism of toxicity test for surface water. Toxicity test with water flea is categorized into two parts. One is acute toxicity test with observing immobility and mortality and the other is chronic toxicity test determined by survival and reproduction of water flea. Heartbeat measurement of water flea was designed as a short-term toxicity test in this study. Direct measurement of heartbeat under microscope by aid of video camera gives and early diagnosis of mortality in short time. Therefore, the effects of measuring illumination, measuring time, and non-feeding during the test on heartbeat of water flea was evaluated to establish a new test approach. Test organisms used in this study are Daphnia magna, a well standardizes toxicity test organism, and Simocephalus mixtus, a newly refined organism $IC_{50}$ values of these test organism by heartbeat measurement were compared and discussed. It was found that toxicity test by heartbeat measurement was a reproducible, easy and simple method accomplished in a few hours.

• Environmental Analysis Health and Toxicology
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• 제18권4호
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• pp.305-310
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• 2003

A rapid, inexpensive enzymatic method is proposed for indirect water quality testing in terms of heavy metal toxicity. The activity of glucose-6-phosphate dehydrogenase was applied for heavy metal toxicity test as an effective criterion in water quality. The toxicity of Pb (lead) and Cd (cadmium) for water flea, Moina macrocopa, were evaluated for 2-8 days with variables of mobilization ability. And the reproduction impairment of Moina macrocopa were investigated as the parameter of chronic toxicity test for Pb and Cd. As a result, the EC$_{50}$ for immobilization of Moina macrocopa were Pb and Cd were 1.6749 and 0.4683, respectively. The values of reproductive impairment to Moina macrocopa for Pb and Cd were 9.5938 and 8.3264 in EC$_{50}$ A significant alteration of G6PDH (Glucose-6-phosphate dehydrogenase) activity of Moina macrocopa was observed when Cd and Pb were treated in media. The results obtained indicate that G6PDH activity of Moina macrocopa can be used as an indicative parameter in aquatic toxicity tests for heavy metals.als.

• Environmental Analysis Health and Toxicology
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• 제30권
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• pp.7.1-7.7
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• 2015

Objectives The widely promising applications of graphene nanomaterials raise considerable concerns regarding their environmental and human health risk assessment. The aim of the current study was to evaluate the toxicity profiling of graphene family nanano-materials (GFNs) in alternative in vitro and in vivo toxicity testing models. Methods The GFNs used in this study are graphene nanoplatelets ([GNPs]-pristine, carboxylate [COOH] and amide [$NH_2$]) and graphene oxides (single layer [SLGO] and few layers [FLGO]). The human bronchial epithelial cells (Beas2B cells) as in vitro system and the nematode Caenorhabditis elegans as in vivo system were used to profile the toxicity response of GFNs. Cytotoxicity assays, colony formation assay for cellular toxicity and reproduction potentiality in C. elegans were used as end points to evaluate the GFNs' toxicity. Results In general, GNPs exhibited higher toxicity than GOs in Beas2B cells, and among the GNPs the order of toxicity was pristine > $NH_2$ > COOH. Although the order of toxicity of the GNPs was maintained in C. elegans reproductive toxicity, but GOs were found to be more toxic in the worms than GNPs. In both systems, SLGO exhibited profoundly greater dose dependency than FLGO. The possible reason of their differential toxicity lay in their distinctive physicochemical characteristics and agglomeration behavior in the exposure media. Conclusions The present study revealed that the toxicity of GFNs is dependent on the graphene nanomaterial's physical forms, surface functionalizations, number of layers, dose, time of exposure and obviously, on the alternative model systems used for toxicity assessment.