• Journal of Environmental Health Sciences
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• v.44 no.2
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• pp.153-159
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• 2018

Objectives: This study was carried out to determine $LD_{50}$ of benzo[a]pyrene to decide the possibility to designate them as toxic substance on the Act on the Registration and Evaluation, etc. of Chemical Substances, and to suggest that they should be managed in what level on the Chemical Control Act. Methods: Based on the result of a preliminary study, 300 mg/kg was set as the middle dose. A highest dose of 2,000 mg/kg and a lowest dose of 50 mg/kg were selected based on the OECD TG 423. Benzo[a]pyrene was orally administered once to female and male SD rats at dose levels of 50, 300, 2,000 mg/kg (body weight). All animals were monitored daily for clinical signs and mortality over 14 days. Also testicular spermatid count, motility and etc. were examined as well. Results: Under the condition of this experiment, $LD_{50}$ of benzo[a]pyrene was assumed to be >2,000 mg/kg. In the lesion according to autopsy, there were no specific symptoms in the control and experimental groups. At 2,000 mg/kg, a decrease in the sperm motility was observed. Benzo[a]pyrene should be designated to be toxic substance as the material assumed to be reproduction-toxicity on the Act on the Registration and Evaluation, etc. of Chemicals. Therefore we should abide by legal procedures determined by Chemicals Control Act in treating it. Conclusion: Considering the significant result that sperm motility in the experimental group was inferior to that in the reference group, we suggest that benzo[a]pyrene be designated as a toxic substance.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1993.06a
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• pp.4-5
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• 1993

Toxicity tests in our laboratory are conducted usually with mass-reared organisms. They are under the same environmentel conditions throughout seasons and are supplied at specific age. A total of 38 species of aquatic organisms are being reared. We have attempted to establish pruified strains or to select clones of various parthenogenic organisms. The merits or demerits of our culturing test organisms are discussed. The differences in the susceptibility among clones or strains of test organism are also discussed. For a single species test, algae, daphnia, fish are often used. However, we usually use early stages, but occasionally, adults fish are used for reproduction tests. As an another important aspect, the toxicity through food chains has been studied. In this study, we select a pair of species belonging different trophic levels. The differences between single species tests and multispecies tests will be discussed. Even a single species test intends to assess the effects of chemicals on ecosystem levels, however, this idea is not applicable to ecosystems. Single species tests with standard organisms and multispecies tests are contradictory in concept. One type of multispecles tests is indoor microcosms being composed of severel species artificially assembled, and another is composed of natural components (both indoor and outdoor). We have used three types of outdoor mesocosms using ponds and three types of artificial streams. The mesocosms is useful to not only to analyze the floral or faun61 changes but also to study the fate or behaviour of chemicals in naturd environments. Lastly, usefulness of the field observation or experiments or semi-field experiments will be discussed. This will enhance the exploitation of early warning systems utilizing indicator organisms or animal behaviour.aviour.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.3
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• pp.161-167
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• 2020

Objective: Oxidative stress has been suggested as a possible mechanism for the adverse effects of heavy metal toxicity on male reproduction. Cichorium intybus L. is used in Iranian folk medicine as a hepatoprotective agent as well as for its supposed fertility-enhancing properties. The present study was performed to investigate whether the ethanolic extract of C. intybus leaves could protect male rats against lead-induced testicular oxidative stress. Methods: In this experimental study, adult Wistar rats were treated with 0.1% lead acetate in drinking water alone or with 50, 100, or 200 mg/kg body weight of C. intybus extract via gavage once daily for 70 days. The weight of their reproductive organs, levels of serum hormones, histometric parameters of the seminiferous tubules, epidydimal sperm quality, and oxidative stress status were evaluated. Results: The testis weight, seminiferous tubule diameter, epididymal sperm count, serum testosterone level, and testicular levels of superoxide dismutase and glutathione peroxidase were significantly reduced (p< 0.05) in the lead-treated rats. Moreover, significantly (p< 0.05) higher levels of malondialdehyde were observed in the lead-exposed group compared to the control. However, the co-administration of C. intybus ethanolic extract in lead-treated rats was associated with a significant improvement in reproductive parameters. Conclusion: We conclude that C. intybus leaf extract has the potential to prevent lead-induced testicular toxicity and to suppress the adverse effects of lead on male reproductive health.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.110-110
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• 2002

Rapidly progressive interstitial renal fibrosis has recently been reported in young women who have been on a slimming regimen including chinese herbs. Aristolochic acid, suspected as the causal factor of this renal disease, is a well known carcinogen. It has been known that Madouling (Aristolochiae fructus) contains aristolochic acid. The objective of this study was to investigate the effects of Madouling, Madouling-tang, which are the extract mixture from 10 different chinese herbs including Madouling, and aristolochic acid on reproductive and developmental toxicity. Female rats were administered orally with the extracts of Madouling, madouling-tang, and aristolochic acid from 14 days before mating to day 17 of gestation. Madouling (8mg/kg) decreased fertility in the 8mg/kg group, but Madouling-tang and aristolochic acids did not. Significant decrease of mean fetal body weights were observed in the 16mg/kg group of aristolochic acids. External, visceral and skeletal malformation of fetuses were not observed with treatment. Histopathological examination showed the discrete damage of kidney in the 8mg/kg group of Madouling and 16mg/kg groups of aristolochic acid. In whole embryo culture, Madouling and Madouling-tang caused the retardation of growth and development of embryo in the dose of 1 $\mu$g/ml and 0.02 $\mu\textrm{g}$/kg, respectively while aristolochic acids showed the similar effect in the dose of 300 $\mu\textrm{g}$/kg. These results indicate that Madouling, up to 0.05mg/kg (prescription dose to human) has no adverse effects on the fertility, reproduction and development of Sprague-Dawley rats.

• Molecular & Cellular Toxicology
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• v.5 no.3
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• pp.216-221
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• 2009

Bisphenol A (BPA) is commonly used in the production of pharmaceutical, industrial, and housing epoxy, as well as polycarbonate plastics. Owing to its extensive use, BPA can contaminate the environment either directly or through derivatives of these products. BPA has been classified as an endocrine disruptor chemicals (EDCs), and the primary toxicity of these EDCs in males involves the induction of reproductive system abnormality. First, in order to evaluate the direct effects on the Y chromosome associated with reproduction, we evaluated Y chromosome abnormalities using a Y chromosome microdeletion detection kit. However, we detected no Yq abnormality as the result of BPA exposure. Secondly, we performed high-density oligonucleotide array-based comparative genome hybridization (CGH) to assess genomic alteration as a component of our toxicity assessment. The results of our data analysis revealed some changes in copy number. Seven observed features were gains or losses in chromosomal DNA (P-value<1.0e-5, average log2 ratio>0.2). Interestingly, 21 probes of chr7:7312289-10272836 (qA1-qA2 in cytoband) were a commonly observed amplification (P-value 3.69e-10). Another region, chr14:4551029-10397399, was also commonly amplified (P-value 2.93e-12, average of log2 ratios in segment>0.3786). These regions include many genes associated with pheromone response, transcription, and signal transduction using ArrayToKegg software. These results help us to understand the molecular mechanisms underlying the reproductive effects induced by BPA.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.164-172
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• 1996

The comparative toxicity of abamectin to the predatory mite, Amblyseius womersleyi Schicha and the spider mites, Tetranychus urticae Koch and T. kanzawai Kishida was evaluated by leaf disc method. Abamectin was much less toxic to A. womersleyi than to the spider mites. Although survival rate of adult females of A. womersleyi tended to decrease with increasing abamectin concentration, 8-78% of predators remained alive at concentrations of 0.38-6 ppm. Likewise, reproduction was significantly reduced with increasing abamectin concentration. Abamectin neither affect the hatch of A. womersleyi eggs nor the development of surviving immature predators. Survival of immature predators decreased with increasing abamectin concentration. However, 42-90% of immature predators reached adulthood at 0.38-3 ppm. Adult female predators survived on a diet of spider mites intoxicated with abamectin, although their fecundity and the sex-ratio of the progeny were significantly affected. Abamectin at selective sublethal concentrations (0.38-0.75 ppm) could he of value in adjusting predatorlprey ratios in integrated management of T. urticae and T. kanzawai.

• Molecules and Cells
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• v.38 no.12
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• pp.1096-1104
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• 2015

Particulate $matter_{2.5}$ ($PM_{2.5}$) is notorious for its strong toxic effects on the cardiovascular, skin, nervous, and reproduction systems. However, the molecular mechanism by which $PM_{2.5}$ aggravates disease progression is poorly understood, especially in a water-soluble state. In the current study, we investigated the putative physiological effects of aqueous $PM_{2.5}$ solution on lipoprotein metabolism. Collected $PM_{2.5}$ from Seoul, Korea was dissolved in water, and the water extract (final 3 and 30 ppm) was treated to human serum lipoproteins, macrophages, and dermal cells. $PM_{2.5}$ extract resulted in degradation and aggregation of high-density lipoprotein (HDL) as well as low-density lipoprotein (LDL); apoA-I in HDL aggregated and apo-B in LDL disappeared. $PM_{2.5}$ treatment (final 30 ppm) also induced cellular uptake of oxidized LDL (oxLDL) into macrophages, especially in the presence of fructose (final 50 mM). Uptake of oxLDL along with production of reactive oxygen species was accelerated by $PM_{2.5}$ solution in a dose-dependent manner. Further, $PM_{2.5}$ solution caused cellular senescence in human dermal fibroblast cells. Microinjection of $PM_{2.5}$ solution into zebrafish embryos induced severe mortality accompanied by impairment of skeletal development. In conclusion, water extract of $PM_{2.5}$ induced oxidative stress as a precursor to cardiovascular toxicity, skin cell senescence, and embryonic toxicity via aggregation and proteolytic degradation of serum lipoproteins.

• Toxicological Research
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• v.26 no.1
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• pp.67-74
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• 2010

The present study was conducted to obtain information on the effects of amitraz on reproductive and developmental parameters in rats. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and up to lactational day 4. During the study period, clinical signs, body weights, food intake, organ weights, reproductive and littering findings, necropsy findings, sperm parameters, and histopathology were examined. At 360 ppm, decreases in the body weight gain, food consumption, and the number of live pups and an increase in the post-implantation loss were observed. In addition, decreases in the seminal vesicle weight and sperm motility were found in males. At 120 ppm, a decrease in the food consumption was found transiently in both males and females, but no reproductive and developmental toxicity was observed in both sexes. There were no signs of either general or reproductive and developmental toxicity in the 40 ppm group. Based on these results, it was concluded that the repeated oral administration of amitraz to rats resulted in a decrease in the food consumption at 120 ppm and decreases in the seminal vesicle weight, sperm motility, and the number of live pups and an increase in the post-implantation loss at 360 ppm in rats. Under these experimental conditions, the no-observed-adverse-effect level (NOAEL) of amitraz for general and reproduction/developmental toxicity was believed to be 120 ppm, and the no-observed-effect level (NOEL) of amitraz was believed to be 40 ppm in rats.

• Korean Journal of Ecology and Environment
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• v.45 no.3
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• pp.271-277
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• 2012

The present study was conducted to assess the suitability of domestic natural waters as a Daphnia magna culture medium. In order to assess survival rate and reproductive output, young female daphnids (parent animals), aged less than 24 hours at the start of the test and produced in the Elendt M4 medium, were exposed to Elendt M4 medium, de-chlorinated tap water, and natural mineral water for 21 days. D. magna cultured in Elendt M4 medium (reference medium) and natural mineral water met the criteria of OECD No. 211, Daphnia magna Reproduction Test Guidelines in terms of percent adult survival, first day of reproduction, and average young production. However, the mortalities of adult daphnids observed in de-chlorinated tap water were more than 20% in two reproduction tests for 21 days. Mortality was observed on exposure days 13, 15, and 18 in de-chlorinated water. The use of D. magna is recommended in water of hardness >80 mg $CaCO_3\;L^{-1}$. However, the hardness of de-chlorinated tap water used in the present study was 50~53 mg $CaCO_3\;L^{-1}$. Therefore, it is judged that the delayed mortalities observed in de-chlorinated tap water were caused by a rapid decreased in hardness when the medium was changed from Elendt M4 to de-chlorinated tap water. When D. magna is cultured using domestic natural waters (underground water, surface water, and de-chlorinated water), the quality-control (QC) data should be maintained through a standardization for health assessment method, toxicity test method using reference chemical, test intervals of reference toxicant toxicity test, and data treatment and interpretation. In the long term, national research programs are needed for the development of test species which are representative of domestic aquatic environmental conditions among indigenous daphnids.

• Development and Reproduction
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• v.1 no.2
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• pp.125-132
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• 1997

To investigate the cadmium (Cd) toxicity on the testis, male rats were treated with 1, 2, 4 and 8 mg/kg of Cd by IP. According to histochemical studies, Cd-treated testis tissue showed death of spermatozoa, death of Sertoli cells, death of all the spermatogenic cells, and finally disappearance of basal lamina of seminiferous tubules with increasing doses, and showed decreased ground substances and Leydig cells, increased inflammatory cells and fibroblasts, and fibroblasts, and finally disappearance of ground substances and all the cells except fibroblasts within interstitial tissues with increasing doses. According to biochemical studies, two kinds of proteins, 25 and 45 kDa, were dramatically disappeared from the total protein of rat testis treated with Cd comparing to normal testis. The result of electrophoresis of total protein suggests that actin (45 kDa), presumed on its mmolecular weight and amount, in the testis-cells is the primary target of Cd poisoning. Although its exact mechanism is not clear, the disappearance of two proteins when testis is exposed to Cd should give some clues to understnad the mechanism of necrosis of testis tissue crumbling by heavy metal pollutant such as Cd.