• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.1-7
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• 2013

This study was on leaching test(KSLT, TCLP) of the aggregate for the products(RA-1) and for the site(RA-2) to evaluate the characteristics of contaminants and the possibility of contamination arising from the aggregate. On the basis pH, conductivity and heavy metal contents in the aggregate, RA-1 indicated higher than RA-2. As a result of the leaching test, the pollutants were eluted from the aggregate increased as the particle size of the aggregate was smaller. The pH in the aggregate had a strong alkali by a pH value of 9.0~12.3, the conductivity was higher in less than 10mm RA-1 due to the leaching of dissolved inorganic ions. The heavy metals satisfied the leaching standards of KSLT and less 10% was eluted from the aggregate. As a result of evaluating water pollution possibility of the aggregate, the pH displayed in items with a very high possibility of contamination, conductivity and turbidity did in item with a low possibility of contamination and on the other hand the heavy metals did in item with a very low possibility of contamination.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.2
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• pp.101-112
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• 2003

This paper designs and implements the management system that can calibrate the contamination vulnerability of the ground water, using an object oriented data model. Geographic-objects are specified by features extracted from an applicable geographic domain, and geographic-fields are defined by chemical factors extracted from each driven water. To show the topological relationships among the geographic-objects and the geographic-fields, this paper attach the weight and the ratio of the drastic model to chemical factors represented on the land use digital map and the ground water digital map. The geographic feature class, administrative boundary class, land use class and driven water class consist of a class composition hierarchy for evaluating the convenient contamination vulnerability calibration with spatial relationships among the well objects. Therefore, this management system for evaluating the contamination vulnerability can also contribute to the application of other natural environments.

• Journal of Preventive Medicine and Public Health
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• v.50 no.3
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• pp.158-164
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• 2017

Objectives: To identify bacterial contamination rates of laryngoscope blades and handles stored in emergency crash carts by hospital and area according to the frequency of intubation attempts. Methods: One hundred forty-eight handles and 71 blades deemed ready for patient use from two tertiary hospitals were sampled with sterile swabs using a standardized rolling technique. Samples were considered negative (not contaminated) if no colonies were present on the blood agar plate after an 18-hour incubation period. Samples were stratified by hospital and according to the frequency of intubation attempts (10 attempts per year) using the ${\chi}^2-test$ and Fisher exact test. Results: One or more species of bacteria were isolated from 4 (5.6%) handle tops, 20 (28.2%) handles with knurled surfaces, and 27 (18.2%) blades. No significant differences were found in microbial contamination levels on the handle tops and blades between the two hospitals and two areas according to the frequency of intubation attempts. However, significant differences were found between the two hospitals and two areas in the level of microbial contamination on the handles with knurled surfaces (p<0.05). Conclusions: Protocols and policies must be reviewed to standardize procedures to clean and disinfect laryngoscope blades and handles; handles should be re-designed to eliminate points of contact with the blade; and single-use, one-piece laryngoscopes should be introduced.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.1-8
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• 1997

The contamination structure and process on SUS 316 under various exposure conditions were investigated using x-ray photoelectron spectroscopy. The metal-oxide, metal-H-oxides, CO, COH, and $C_xH_y$ are the main components of contaminants on the SUS surface. The compositional profiles of the contaminants are shown to be $C_xH_y$/CO(COH)/metal-oxide on SUS. The contamination proceeds in two steps. The oxidation of the metallic constituents followed by adsorption of hydrocarbons. Under UHV conditions the contamination is mainly due to the oxidation, and, as the exposure time increases, the oxidation continues. In HV or higher pressure, most of the oxides are formed almost immediately after exposure and as the exposure time increases the contamination of hydrocarbons continues to grow. For the SUS sample exposed to atmosphere, the metal oxide is distributed deep inside the surface with an exponentially decreasing concentration, and its thickness is nearly in the order of photoelectron mean free path. It is also seen that the Fe oxide is segregated over Cr oxide in the highly oxidized samples.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.19-35
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• 2003

In order 새 investigate the spatial and seasonal variations of heavy metal pollution in heavily industrialized urban area, urban roadside sediments were collected for five years from gully pots in Seoul City. A series of studies have been carried out concerning the physicochemical characteristics of the sediments in order to evaluate the contamination of heavy metals such as Cd, Co, Cr, Cu, Ni, Pb and Zn. Roadside sediments and uncontaminated stream sediments were analyzed for total metal concentrations using acid extraction. The roadside sediments are characterized by very high concentrations of Zn (2,665.0$\pm$1,815.0 $\mu\textrm{g}$/g), Cu (445.6$\pm$708.0 $\mu\textrm{g}$/g), Pb (214.3$\pm$147.9 $\mu\textrm{g}$/g) and Cr (182.1$\pm$268.8 $\mu\textrm{g}$/g), indicating an artificial accumulation of these metals to the sediment chemistry. Comparing with average contents of uncontaminated stream sediments, roadside sediments were shown zinc 14 times (up to 64.4), copper 9 times (up to 181.7), lead 6 times (up to 63.7), cobalt 6 times (up to 168.7), nickel 4 times (up to 98.4), cadmium 2 times (up to 12.8) and chrome 2 times (up to 40.2) high content. The relative degree of heavy metal pollution for roadside sediments collected from each district in Seoul City is evaluated using the “geoaccumulation index”. As a result, heavy-metal contamination is highest centering the oldest residential district and industry area, and contamination level decreases as go to outer block of the city. The factor analysis results indicate that the levels of Cu, Ni, Fe and Cr are strongly related to numbers of factories, whereas the concentrations of Cr, Zn and Cd dependant on pollution index, indicating artificial contamination due to site-specific traffic density.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.191-196
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• 2007

The slaughter process for cattle will inevitably transfer some bacteria onto the carcasses. The goal of food safety programs is to minimize and effectively remove this contamination. This study was attempted by the Verif $EYE^{TM}$ machine-vision technology that might be useful for reducing microbial indicator counts and could reduce the contamination chance of E coli O157:H7 and Salmonella spp on beef carcasses. For the evaluation of the effectiveness of the Verif $EYE^{TM}$ technology, 80 samples were examined by the inspection device over 15 days. On an examination of FDS-positive samples compared to negative controls from the same carcasses, aerobic plate counts were bigger than the negative control samples (5.26 vs 4.60 log). Enterobacteriaceae counts were greater on the positive samples than the corresponding negative control samples (2.07 vs 1.17log). There was a consistent correlation between samples detected by the Verif $EYE^{TM}$ system with detectable counts. For example, 100% of positive samples had detectable APC and 91.2% of positive samples had detectable TCC. Therefore, if areas detected as positive for contamination by the Verif $EYE^{TM}$ system were removed from the carcasses, significant sources of microbial contamination will be reduced for objective compliance with HACCP. This results suggest that the use of Verif $EYE^{TM}$ machine-vision technology might be useful for reducing microbial indicator counts (APC, TCC) and could help reduce the risk of presence of E coJi O157:H7 and Salmonella spp on Beef carcasses.

• Journal of Pharmaceutical Investigation
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• v.39 no.4
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• pp.263-267
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• 2009

The purpose of this study is to evaluate the efficacy of stipulated cleaning process, and the prohibition of cross-contamination and microbiological contamination, which inadequate cleaning in multi-production could occur, through cleaning validation of multi-purpose facility used to produce five biopharmaceutical products as sterile injection. After production of five biopharmaceutical products such as hGH, rhGCSF, rhEPO, rhFSH and rhIFN using vial filling machine, the cleaning validation such as residual analysis of active ingredients or human serum albumin, measurement of total organic carbon (TOC), residual analysis of detergent and microbiological contamination were carried out. In the case of rhGH and rhGCSF clean validations, drug residues were not detected. Furthermore, in the case of rhEPO, rhFSH and rhIFN clean validations, human serum albumin residues were not detected. At TOC (total organic carbon) analysis, all clean validations gave the TOC of about average 137.93%, not more than 150% of acceptance criteria. At sodium analysis for the checking of residues of cleaning agent, sodium residues were not detected. In sterility test, they showed no microbiological contamination of bacteria and fungi. Thus, this cleaning validation was determined as successful in protection of cross-contamination and induction of safety in multi-purpose facility.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.162-167
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• 2003

The pool $(3m{\times}6m{\times}10m)$ in Irradiated Materials Examination Facility is usually used for the purpose of taking the specimen out of cask loaded into the pool, and carrying in/out the specimen to/from the hot cell. Always, it must be cared for the water into the pool to be fine condition because all operation are worked with the naked eye during taking an irradiated materials out of the cask and plunging them in the bucket-elevator. In the aspects of the radioactive contamination control, remained substances in the water must be controlled so that the amount of substances are to be lower than the standard amount prescribed by RCA Korea Activity in a part of radioactive contamination control. This paper describes a behavior of the quality of water and the radioactive contamination of pool water for working of pool water purging system and contamination diffusion distribution bahavior of each specimens carried in/out.

• Korean Journal of Veterinary Service
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• v.37 no.4
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• pp.253-261
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• 2014

Porcine circovirus disease (PCVD) is a major problem of swine industry worldwide, and diagnosis of PCV2, causal agent of PCVD, has been doing in clinical laboratories of pig disease by polymerase chain reaction (PCR) methods. But the PCR analyses have a serious problem of misdiagnosis by contamination of DNA, in particular, from carryover contamination with previously amplified DNA or extracted DNA from field samples. In this study, an uracil DNA glycosylase (UNG)-based direct PCR (udPCR) without DNA extraction process and DNA carryover contamination was developed and evaluated on PCV2 culture and field pig samples. The sensitivity of the udPCR combined with dPCR and uPCR was same or better than that of the commercial PCR (cPCR) kit (Median diagnostics, Korea) on PCV2-positive serum, lymph node and lung samples of the pigs. In addition, the udPCR method confirmed to have a preventing ability of mis-amplification by contamination of pre-amplified PCV2 DNA from previous udPCR. In clinical application, 170 pig samples (86 tissues and 84 serum) were analysed by cPCR kit and resulted in 37% (63/170) of positive reaction, while the udPCR was able to detect the PCV2 DNA in 45.3% (77/170) with higher sensitivity than cPCR. In conclusion, the udPCR developed in the study is a time, labor and cost saving method for the detection of PCV2 and providing a preventing effect for DNA carryover contamination that can occurred in PCR process. Therefore, the udPCR assay could be an useful alternative method for the diagnosis of PCV2 in the swine disease diagnostic laboratories.

• Journal of Radiation Protection and Research
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• v.27 no.3
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• pp.165-170
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• 2002

Combined with deposition model onto the ground of radionuclides, the influence of radioactive contamination to agricultural products was analyzed due to wet deposition as well as dry deposition from radioactive air concentration during a nuclear emergency. The previous dynamic food chain model, in which initial input parameter is only radionuclide concentrations on the ground, was improved for the evaluating of radioactive contamination to agricultural products from either radionuclide concentrations in air or radionuclide concentrations on the ground. As the results, in case of deposition onto the ground, wet deposition was more dominant process than thy deposition. While the contamination levels of agricultural products were dependent on the a variety of factors such as radionuclides and rainfall rate. It means that the contamination levels of agricultural products are determined from which is more dominant process between deposition on the ground and interception onto agricultural plants.