• 제목/요약/키워드: Contamination agents

검색결과 114건 처리시간 0.022초

Studies on the Storage Characteristics of Angelica dahuricae Radix, Glehnia littoralis Radix Treated with Gamma-irradiation (감마선 처리에 의한 방풍, 백지의 저장성 연구)

  • Kim, Soo-Min;Kim, Eun-Ju
    • The Korea Journal of Herbology
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    • 제24권1호
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    • pp.1-7
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    • 2009
  • Objectives : The purpose of this study is to investigate on storage characteristics of Herbal materials treated with Gamma-irradiation(10 KGy). Methods : This experiments were carried out by field survey and storage characteristics were carried out by physicochemical determination. Results : Antimicrobial activity of oriental medicine materials(Angelica dahurica Radix, Glehnia littoralis Radix) were examined, together with investigation of effects on gamma-irradiation. Oriental medicine materials contaminated in microbial cell were tend to be pinhole in packaging materials(polypropylene) by bug and Larva. At the same time, PVDC (polyvinylldichloride) package also was founded in bug and Larva by microbial contamination during storage in room temperature. Conclusions : In conclusion, it is very desirable to dose gamma-irradiation(10 KGy) in these oriental medicine materials in order to prevent microbial activity.

A Study on Several Minerals Contaminated with Asbestiform Fibers in Korea (우리나라 일부 광물중 석면섬유의 함유에 대한 조사)

  • Choi, Jung Keun;Paek, Do Myung;Paik, Nam Won;Hisanaga, Naomi;Sakai, Kiyoshi
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • 제8권2호
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    • pp.254-263
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    • 1998
  • A worker employed in a serpentine mine was found developed mesothelioma as the first case of Korea in 1997. Asbestos was known as a causative agent for mesothelioma. Thus, asbestos contamination in mines could be a big health threat to those workers who were unknowingly exposed. However, there was no report that any minerals found in Korea contained asbestos. This study was carried out to find the presence of any asbestiform fibers in minerals which could be obtained in Korean mines. We examined fifteen minerals from 44 mines which were suspected contaminated with asbestiform fibers. Asbestiform analysis was done with high resolution transmission electron microscope(TEM), with energy dispersive X-ray spectroscope(EDX) and X-ray diffraction(XRD) analyses. Among asbestiform fibers, chrysotile was found in chrysotile, serpentine, talc and pyrophylite specimens from 11 mines. Tremolite was found in tremolite and talc specimens from three mines. Mordenite was found in zeolite specimens from two mines. Wallastonite and sepiolite were found in wallastonite and sepiolite specimens respectively. Crocidolite, antigorite and actinolite were found from talc specimens. But no asbestiform fiber contaminants were found in doromite, vermiculite, limestone, marble, gypsum, kaolin, and clary specimens. Thus, these asbestiform fibers such as such as chrysotile, tremolite, mordenite, crocidolite, antigorite and actinolite could be the responsible agents for the health hazards such as mesothelioma and other cancers.

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Urine and Hair Metal Concentrations in Subjects with Long Term Intake of Herbal Medicine

  • Park Yeong-Chul;Lee Sun-Dong;Park Hae-Mo;Kim Jong-Bong
    • Toxicological Research
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    • 제22권1호
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    • pp.47-54
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    • 2006
  • One of the main attractions of treatment with herbal medicine is its apparent lack of side effects compared with the drug therapies used in allopathic medicine. However, evidence from various countries suggest that Asian herbal medicine carry a significant risk of contamination with toxic heavy metals at levels that may seriously threaten health. The aims of this study were to analyze and compare concentrations of heavy metals in urine and hair from 184 patients taking herbal medicines in the form of decoctions and/or pills in comparison to 101 control subjects taking either Western or no medications. Levels of metal concentrations exceeding WHO reference values were observed in a number of hair and urine samples for all subjects. After adjusting for potential confounders, taking decoctions or pills was associated with higher levels of some metals (such as Cu, Pb in urine), as well a higher odds ratio of exceeding the upper limit of reference ranges for Pb, Hg in hair. In contrast, taking decoctions or pills was associated with lower levels of some metals (such as Cu in urine and Cd, Cu, Hg, Pb in hair), suggesting that some herbal medicines may have a chelating effect on heavy metals in the body. Overall, the results obtained in the study show a mixed picture and suggest that heavy metals contamination in herbs is sometimes present, but may also be counteracted by the potential for some herbal medicines to act as chelating agents. Further study must be followed to obtain more concrete evidence.

The Effect of Geological Media on the Denitrification of Nitrate in Subsurface Environments (지중환경 내 지질 매체가 질산염의 탈질 반응에 미치는 영향에 대한 고찰)

  • Jeon, Ji-Hun;Lee, Woo-Chun;Lee, Sang-Woo;Kim, Soon-Oh
    • Journal of Soil and Groundwater Environment
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    • 제25권2_spc호
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    • pp.16-27
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    • 2020
  • Nitrate contamination has received much attention at local as well as regional scales. The domestic situation is not out of exception, and it has been reported to be very serious, particularly within agricultural areas as a result of excessive usage of nitrogen fertilizers. Meanwhile, nitrate can be naturally attenuated by denitrification in subsurface environments. The denitrification occurs through biotic (biological) and abiotic processes, and numerous previous studies preferentially focused the former. However, abiotic denitrification seems to be significant in specific environments. For this reason, this study reviewed the previous studies that focused on abiotic denitrification processes. Firstly, the current status of nitrate contamination in global and domestic scales is presented, and then the effect of geological media on denitrification is discussed while emphasizing the significance of abiotic processes. Finally, the implications of the literature review are presented, along with future research directions that warrant further investigations. The results of previous studies demonstrated that several geological agents could play a vital role in reducing nitrate. Iron-containing minerals such as pyrite, green rust, magnetite, and dissolved ferrous ion are known to be powerful electron donors triggering denitrification. In particular, it was proven that the rate of denitrification by green rust was comparative to that of biological denitrification. The results indicate that abiotic denitrification should be taken into account for more accurate evaluation of denitrification in subsurface environments.

Identification of Jet fuel (JP-8) in Petroleum Hydrocarbon Contaminated Soil through the Qualitative Analysis of Antioxidants (유류 오염 토양 중 산화방지제 정성 분석을 통한 항공유(JP-8) 유종 판별)

  • Kim, Yonghun;Lee, Goontaek;Jang, Hanjeon;Jo, Yunju;Kim, Moongun;Choi, Jaeho;Kang, Jiyoung
    • Journal of Soil and Groundwater Environment
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    • 제27권4호
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    • pp.37-48
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    • 2022
  • Accurate analysis of petroleum hydrocarbons in soil is an important prerequisite for proper source tracking of contamination. Identification of petroleum compounds is commonly carried out by peak pattern matching in gas chromatography. However, this method has several technical limitations, especially when the soils underwent biological, physical and chemical transformation. For instance, it is very difficult to distinguish jet fuel (JP-8) from kerosene because JP-8 is derivatized from secondary reaction between chemical agents (e.g. anti-oxidants, antifreezer and so on) and kerosene. In this study, an alternative method to separately analyze JP-8 and kerosene in the petroleum hydrocarbon contaminated soil was proposed. Qualitative analyses were performed for representative phenolic antioxidants [2,6-di-tert-butyl phenol (2,6-DTBP), 2,4-di-tert- butylphenol(2,4-DTBP), 2,6-di-tert-butyl-4-methyl phenol (2,6-DTBMP)] using a two dimensional gas chromatograph mass spectrometer (2D GC×GC-TOF-MS). This qualitative analysis of antioxidants in soil would be a useful complementary tool for the peak pattern matching method to identify JP-8 contamination in soil.

Evaluation of Field Application of Soil Conditioner and Planting Chrysanthemum zawadskii on the Roadside Soils Damaged by Deicing Agents

  • Yang, Ji;Lee, Jae-Man;Yoon, Yong-Han;Ju, Jin-Hee
    • Journal of People, Plants, and Environment
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    • 제23권6호
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    • pp.625-636
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    • 2020
  • Background and objects: Soil contamination caused by CaCl2 that is used to deice slippery roads in winter is now recognized as one of the major causes of damage of roadside plants. The aim of this study is to identify the salt mitigation effects of planting Chrysanthemum zawadskii and using a soil conditioner. Methods: The study was conducted at the site where Pinus densiflora f. multicaulis was planted on the roadside between Konkuk University Sageori and Danwol Samgeori located in Chungju-si. We classified the soils collected from the field experimental site according to the degree of the damage caused by deicing agents and divided the site into six blocks of three 80 × 80 cm plots replicated by treatment type. Three selected plots were treated with loess-balls on the soil surface (high salinity with loess-balls, medium salinity with loess-balls, low salinity with loess-balls) and three were left as an untreated control (H = high salinity, M = medium salinity, L = low salinity). The soil properties were measured including pH, EC and exchangeable cations as well as the growth of Chrysanthemum zawadskiia. Results: In the results of soil analysis, pH before planting Chrysanthemum zawadskiia was 6.39-6.74 and in September, five months after planting, the acidity was reduced to 5.43-5.89. Electrical conductivity (EC) was measured to be H > M > L with the higher degree of damage by deicing agents. The analysis of deicing exchangeable cations showed that the content of Ca2+ of soils were significantly correlated to deicing exchangeable cations (Ca2+, Na+, Mg2+) in the shoot part of Chrysanthemum zawadskii. The loess-ball treatment showed a lower content of deicing exchangeable cations than the treatment where Chrysanthemum zawadskiia was planted. Conclusion: In this study, the use of a new system made of loess-balls is proposed as a soil conditioner to protect soils from the adverse effects of road deicing salts. These data suggest that treatment of soil conditioners and planting Chrysanthemum zawadskiia are effective in mitigation of salt stress on the soils damaged by deicing agents.

Preparation of Selectively Permeable Membrane Materials with Enhanced Protective Capability against Blister Agents (수포작용제 방호성능이 향상된 선택투과막 제조)

  • Kwon, Tae-Geun;Kim, Jin-Won;Kang, Jae-Sung;Park, Hyen-Bae;Lee, Hae-Wan;Seo, Hyeon-Kwan
    • Membrane Journal
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    • 제24권2호
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    • pp.167-175
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    • 2014
  • For selectively permeable membrane based on cellulose acetate butyrate (CAB) and polyethyleneimine (PEI) with water vapor transportability and DMMP protective performance, we intended to improve protective performance of the membrane against CEES using several additives. Results showed that CAB/PEI membranes possessed performance with good water vapor permeation (${\geq}1,800g/m^2/day$) and enhanced protective capability against CEES contamination ($7.1{\sim}11.5{\mu}g/cm^2{\cdot}day$). Of these membranes, the membrane containing $Ag^+$ ion and ionic exchange resin showed the best protective performance. And, we identified that the CAB/PEI membranes show excellent protection against aerosols with various particle sizes ($0.005{\sim}3{\mu}m$) simulating biological agents.

Antimicrobial Resistance and Minimum Inhibitory Concentrations of Vibrio parahaemolyticus Strains Isolated from Seawater and Commercial Fisheries (해수 및 시판 수산물에서 분리한 장염비브리오균(Vibrio parahaemolyticus)의 항균제 내성 및 최소발육억제농도의 규명)

  • Cho, Eui-Dong;Kim, Hee-Dai;Park, Kwon-Sam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제52권6호
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    • pp.587-595
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    • 2019
  • Eighty-three Vibrio parahaemolyticus isolates from surface seawater in Gomso Bay on the west coast of Korea, and commercial fisheries from Gunsan fisheries center were analyzed for the presence of virulence genes and susceptibility to 30 different antimicrobials. All 83 isolates were examined for the presence of two virulence genes (tdh or trh) using polymerase chain reaction; however, neither gene was found in any of the isolates. A disk diffusion susceptibility test, showed that all of the strains studied were resistant to clindamycin, oxacillin, ticarcillin, and vancomycin, and also revealed varying levels of resistance to ampicillin (98.8%), penicillin G (95.2%), streptomycin (20.5%), cefoxitin (14.5%), amikacin (6.0%), cephalothin (4.8%), and erythromycin (3.6%). However, all of the strains were susceptible to 19 other antimicrobial agents, including cefepime, cefotaxime, chloramphenicol, gentamycin, nalidixic acid, sulfamethoxazole/trimethoprim, and trimethoprim. All 83 isolates (100%) were resistant to five or more classes of antimicrobials, and two strains exhibited resistance to ten antimicrobial agents. The average minimum inhibitory concentrations against V. parahaemolyticus of clindamycin, oxacillin, ticarcillin, and vancomycin were 55.9, 98.3, 499.3, and 44.3 ㎍/mL, respectively. These results provide new insight into the necessity for seawater sanitation in Gomso Bay and commercial fisheries, and provide evidence to help reduce the risk of contamination by antimicrobial-resistant bacteria.

Antimicrobial Resistance and the Presence of Virulence Genes in Escherichia coli Strains Isolated from Ruditapes philippinarum in Gomso Bay, Korea (곰소만 해역의 바지락(Ruditapes philippinarum)에서 분리한 대장균 (Escherichia coli)의 항균제 내성 및 병원성 유전자의 보유성)

  • Kim, Tae-Ok;Eom, In-Seon;Park, Kwang-Ho;Park, Kwon-Sam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제49권6호
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    • pp.800-806
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    • 2016
  • In total, 151 Escherichia coli isolates from Ruditapes philippinarum in Gomso Bay were analyzed for their susceptibility to 18 different antimicrobial agents and for genes associated with virulence. For virulence genes, each strain of the isolates was positive for the enterotoxigenic E. coli (ETEC)-specific heat-stable toxin (estA), enteroinvasive E. coli (EIEC)-specific invasion-associated locus (iaa) gene and enteropathogenic E. coli (EPEC)-specific attaching and effacing (eae) gene. According to a disk diffusion susceptibility test, resistance to ampicillin was most prevalent (23.2%), followed by resistance to amoxicillin (22.5%), ticarcillin (20.5%), tetracycline (18.5%), nalidixic acid (12.6%), ciprofloxacin (10.6%), streptomycin (9.9%), and chloramphenicol (6.6%). More than 35.8% of the isolates were resistant to at least one antimicrobial agent, and 19.9% were resistant to four or more classes of antimicrobials; these were consequently defined as multidrug resistant. Minimum inhibitory concentration (MIC) ranges for the antimicrobial resistance of the 15 different antimicrobial agents of 54 E. coli strains were confirmed by varying the concentrations from $32-2,048{\mu}g/mL$. Overall, these results not only provide novel insights into the necessity for seawater and R. philippinarum sanitation in Gomso Bay but they also help to reduce the risk of contamination by antimicrobial-resistant bacteria.

IN VITRO STUDY ON THE CYTOTOXICITY OF THE DIFFERENTLY STERILIZED DEMINERALIZED BONE POWDER (멸균방법에 따른 탈회동종골의 세포독성 여부에 관한 실험적 연구)

  • Woo, Ki-Sun;Yim, Chang-Joon;Kim, Se-Won;Kim, Jong-Yeo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제19권3호
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    • pp.287-299
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    • 1997
  • Procurement, cutting, cleansing, freezing, freeze-drying, and demineralization of the allogeneic bone must be made under the germ-free stable condition without bacterial and/or viral contamination. Even thought the bone is procured under the germ free condition, we must have confidence on disinfection of all the solutions that come in contact with tissue during the whole procedure. Lots of antibacterial agents have been introduced for chemical sterilization. Recently ethylene oxide gas sterilization or radiation sterilization is frequently selected as a secendary sterilization procedure. The biological and biochemical response of the graft material differs with the type and concentration of the sterilizing agents, and various toxic reactions have been reported due to the graft material itself and the substance released by the chemicals. The authors conducted the Millipore filter test to observe the toxic effect on L929 fibroblasts according to the effect on activity of succinate dehydrogenase, during the secondary sterilization of the demineralized allogeneic bone powder with irradiation or ethylene oxide gas. The result were as follows : 1. Around the copper disk, positive control group, 10mm diameter discoloration was observed. 2. As same as the negative control group, the disk showed no discoloration. 3. The demineralized allogeneic bone which was sterilized with ethylene oxide gas or irradiation showed no cytotoxicity. 4. From this results, it is suggested that treatment with ethylene oxide gas or irradiation should be effective to sterilize the deminineralized allogeneic bone.

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