Showing papers by "Pilje Kim published in 2016"
TL;DR: The effects of zinc oxide nanoparticles on dams and fetuses were investigated in rats after intravenous injection from gestation day 6 to 20 and lowest observed adverse effect level of injection route was suggested to be 5 mg/kg in dams and no observed adverse effects level was suggested in fetal developmental toxicity.
Abstract: Recent toxicity studies of zinc oxide nanoparticles by oral administration showed relatively low toxicity, which may be resulted from low bioavailability. So, the intrinsic toxicity of zinc oxide nanoparticles needs to be evaluated in the target organs by intravenous injection for full systemic concentration of the administered dosage. Although the exposure chance of injection route is low compared to oral and/or inhalation route, it is important to see the toxicity with different exposure routes to get better risk management tool. In this study, the effects of zinc oxide nanoparticles on dams and fetuses were investigated in rats after intravenous injection (5, 10, and 20 mg/kg) from gestation day 6 to 20. Two of 20 dams in the 20 mg/kg treatment group died during the treatment period. Hematological examination and serum biochemistry showed dose-dependent toxicity in treated dams. Histopathological analysis of treated dams revealed multifocal mixed cell infiltration and thrombosis in lung, tubular dilation in kidneys, and extramedullary hemopoiesis in liver. Total dead fetuses (post-implantation loss) were increased and the body weight of fetus was decreased in the 20 mg/kg treatment group. Statistical differences in corpora lutea, resorption, placental weight, morphological alterations including external, visceral and skeletal malformations were not observed in treated groups. Based on the data, lowest observed adverse effect level of injection route was suggested to be 5 mg/kg in dams and no observed adverse effect level was suggested to be 10 mg/kg in fetal developmental toxicity.
30 citations
TL;DR: In this paper, the presence of PFASs in sixty-five surface water samples collected from coastal areas of three southeastern industrialized bays, four major rivers, and six rice field areas in Korea were analyzed.
Abstract: Perfluoroalkyl substances (PFASs) have been found in water environment globally. However, the difference on occurrence profiles between PFASs in water from coastal areas and inland rivers or/and agricultural areas is still limited. In this study, the presence of thirteen PFASs in sixty-five surface water samples collected from coastal areas of three southeastern industrialized bays, four major rivers, and six rice field areas in Korea were analyzed. Total PFAS concentrations (ng/L) range from 0.22-73.9 (mean=22.1) for the major rivers, 0.54-3.19 (mean=1.77) for the rice field areas, and
17 citations
TL;DR: Pulmonary exposure to these two chemicals commonly found in commercial products can be a potential hazard to human health, and EG appears to amplify the harmful effects of DDAC on the lung.
Abstract: Didecyldimethylammonium chloride (DDAC), an antimicrobial agent, has been reported to induce pulmonary toxicity in animal studies. DDAC is frequently used in spray-form household products in combination with ethylene glycol (EG). The purpose of this study was to evaluate the toxic interaction between DDAC and EG in the lung. DDAC at a sub-toxic dose (100 μg/kg body weight) was mixed with a non-toxic dose of EG (100 or 200 μg/kg body weight), and was administrated to rats via intratracheal instillation. Lactate dehydrogenase activity and total protein content in the bronchoalveolar lavage fluid (BALF) were not changed by singly treated DDAC or EG, but significantly enhanced at 1 d after treatment with the mixture, with the effect dependent on the dose of EG. Total cell count in BALF was largely increased and polymorphonuclear leukocytes were predominantly recruited to the lung in rats administrated with the mixture. Inflammatory cytokines, tumor necrosis factor-alpha and interleukin-6 also appeared to be increased by the mixture of DDAC and EG (200 μg/kg body weight) at 1 d post-exposure, which might be associated with the increase in inflammatory cells in lung. BALF protein content and inflammatory cell recruitment in the lung still remained elevated at 7 d after the administration of DDAC with the higher dose of EG. These results suggest that the combination of DDAC and EG can synergistically induce pulmonary cytotoxicity and inflammation, and EG appears to amplify the harmful effects of DDAC on the lung. Therefore pulmonary exposure to these two chemicals commonly found in commercial products can be a potential hazard to human health.
14 citations
TL;DR: There is a need for careful monitoring of cyanotoxin in reservoir water and aquatic animals to protect public health due to the spatial distribution or temporal variation of microcystin.
Abstract: 【Objectives: Microcystin (MC) produced during cyanobacterial blooms is a worldwide problem presenting a serious health threats to humans and ecosystems. During July through October of 2013, the Ilwol Reservoir experienced a high biomass of phytoplankton (maximum $211.7mg/m^3$ of Chlorophyll-a) containing the toxigenic cyanobacterium Oscillatoria sp. The aim of this study is to analyze MC concentration in the reservoir water, as well as in representative fish species (Carassius cuvieri, Carassius auratus, Channa argus). We also evaluated the human health risk of exposure to MCs accumulated in the fish. Methods: Concentrations of MCs in the water and fish samples were analyzed by liquid chromatography with a triple quadrupole tandem mass spectrometer (LC/MS/MS) and enzyme-linked immunosorbent assay (ELISA). Results: The total levels of four MC variants, including MC-LR, MC-RR, MC-YR and MC-LA were below the WHO drinking water guideline limit (1 ug MC-LR per liter) both for the dissolved and particulate fraction present in the water samples. The mean MC concentrations in the livers of all species were significantly higher than in the gills (p $0.005-0.015{\mu}g/kg{\cdot}day$ , much lower than WHO's provisional tolerable daily intake of $0.04{\mu}g/kg{\cdot}day$ . Conclusion: This study suggests that, owing to the spatial distribution or temporal variation of MC, there is a need for careful monitoring of cyanotoxin in reservoir water and aquatic animals to protect public health.】
TL;DR: In this paper, the authors describe LCA as "a system that allows the user to decide whether or not to participate in a project with the help of a group of stakeholders".
Abstract: 나노기술의 급격한 발전은 다양한 산업응용분야에 기여를 하고 있다. 그러나 나노제품의 증가와 함께, 비의도적인 환경노출이 발생되고 있다. 나노제품에 의한 잠재적인 환경영향은 전과정평가(LCA)를 통해 해석할 수 있다. LCA는 제품의 생산과 폐기에 이르는 전체 공정상의 자원소모 및 배출에 관한 체계적인 해석을 할 수 있다. 본 연구에서는, 나노-TiO2를 이용한 초친수성 유수분리필터를 제조하는 공정에 관하여 LCA를 수행하였다. 이를 위해 무료로 공개된 TOTALTM을 사용하였으며, 6대 환경영향인자인 자원소모, 기후변화, 오존층영향, 산성화, 부영양화, 광화학산화물생성 등의 지표를 해석하였다. 또한 나노-TiO2를 사용하는 것이 유수분리필터 제조공정에서 벌크-TiO2를 사용하는 것보다 긍정적으로 환경영향인자에 기여하는 것으로 파악되었다.