• Title/Summary/Keyword: molecular contamination

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A View of Soil Microbial Contamination on the Three Sandy Beaches in Busan (부산광역시 세 해수욕장 백사장에서 세균 오염도 조사)

  • Huh, Man-Kyu;Cho, Kyung-Soon
    • Korean Journal of Environmental Biology
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    • v.29 no.3
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    • pp.202-207
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    • 2011
  • Bacterial contamination of beach sand was examined in April, June, July, and August. Twenty four topsoil and subsoil samples were taken from the 1m and 5m points from the coastline in three Busan beaches (Haeundae, Gwanganli, and Songjeong). The 5m points from the coastline showed higher coliform contamination than 1 m points. July showed the highest bacterial contamination on beaches among surveyed months. Coliform contamination in the subsoil was higher than that of the topsoil. The bacterial contamination of 5m points of topsoil and subsoil in June except the Songjeong Beach was higher than those of July and August. We investigated Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio cholerae, and Bacillus cereus. Only B. cereus was detected at the beach in August. Although microbiological pollution of the Gwanganli Beach was the highest among three Busan beaches, the degree of contamination was not high compared to those of other countries. However, sandy soil management in public beach for pathogenic microorganisms is needed.

Investigation of Pollution of Polycyclic Aromatic Hydrocarbons and Heavy Metals in Soil near Railway Rails (철도레일 부근 토양의 다환방향족 탄화수소 및 중금속 오염도 조사)

  • Choi, Hyun-Kyung;Yoon, In-Ju;Shin, Tae-Cheon;Kim, Young-Hun
    • Journal of Environmental Science International
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    • v.27 no.11
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    • pp.947-956
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    • 2018
  • Trains have been a major means of transport in Korea during these past decades. However, train facilities such as stations and repair shops are contaminated with organic and inorganic substances. There is a high probability of train facility contamination with polyaromatic hydrocarbons (PAHs). This study evaluated the PAH and heavy metal contamination of soil near railroads in the Kyungpook area. A total of 18 soil samples were collected from the railroads and analyzed for 16 PAHs and 6 heavy metal species. The contamination level of the top soil was found to be slightly higher than that of the subsoil for contamination with PAHs. The ratio of carcinogenic PAH concentration to the total PAH concentration was relatively high, with a maximum of 0.9. The toxicity equivalent (TEQ) of the PAHs were 500.6 ng/kg in the topsoil and 355.5 ng/kg in the subsoil. The ratio of low molecular PAHs (LPAHs) to high molecular PAHs (LPAHs) ranged from 6.7 to 29.5; this shows that contamination is primarily due to combustion of fuel rather than due to petroleum. The ratio of phenanthrene to anthracene and the ratio of fluoranthene to pyrene also show that contamination occurred due to combustion for transportation. The heavy metal contamination level was lower than the Korean standard, but higher than the background concentration; this indicates that the soil was affected by the operation of the railways.

An efficient method using the modified view factor for estimating the molecular backscattering probability in the space conditions (Modified View Factor를 이용한 인공위성 분자오염 역류확률 예측법)

  • Lee, Jin-Won;Lee, Jae-Dal;Yi, Min-Young;Han, Dong-In;Lee, Chang-Ho;Lee, S.-R.
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.4
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    • pp.57-62
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    • 2005
  • Satellite contamination from back-scattered molecules has long been analyzed using the BGK theory or the DSMC technique which are rather inefficient in that they are complicated or take a long time in the analysis. This study presents a new technique of estimating the back-scattering contamination, which is very simple and easy to use like the view factor method and also very accurate. This method, called the modified view factor method, is equivalent to the DSMC in so far as the molecular thermal velocity is much smaller than the satellite velocity and the mean free path much longer than the satellite.

Current Progress of Next Generation Battery of Toxicology-Cellular and Molecular Toxicology

  • Ryu, Jae-Chun;Kim, Youn-Jung
    • Molecular & Cellular Toxicology
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    • v.1 no.1
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    • pp.26-31
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    • 2005
  • The detection and the regulation of man-made synthetic chemicals and the establishment of toxicity that may pose a genetic hazard in our environment are subjects of great concern because of its close correlation between environmental contamination and human health. Since the tens of thousands of man-made chemicals that have been introduced into the environment in the last few decades must also be tested for their damaging effect on DNA, the agents that cause this damage must be identified.

Contamination patterns of Listeria spp. in pork processing plants using random amplified polymorphic DNA (RAPD를 이용한 돈육 가공장의 Listeria 오염양상 분석)

  • Ha, Sung-Yeol;Choi, Weon-Sang;Bahk, Gyung-Jin;Hong, Chong-Hae
    • Korean Journal of Veterinary Research
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    • v.45 no.3
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    • pp.359-367
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    • 2005
  • This study was carried out to understand the contamination patterns of Listeria in pork processing plants. A total of 402 samples were collected from carcass, pork during processing, surfaces of equipment and environment, and 238 isolates of Listeria species were identified. L. innocua was found in 64.7% of the isolates, L. monocytogenes in 33.2%, and L. welshimeri in 2.1%. Random amplified polymorphic DNA (RAPD) analysis performed to investigate the origin and routes of Listeria contamination, showed 21 composite types of L. monocytogenes and 26 composite types of L. innocua. It was confirmed that Listeria contamination begins with contaminated incoming carcass and ever-present contaminants in the processing environments. The persistence and dissemination of the same strain of L. monocytogenes and L. innocua throughout the processing line revealed that the sanitation standard operating procedure should be implemented to minimize the risk of colonization in the workplace. Molecular subtyping of L. innocua allowed us to tracing the possibility of cross-contamination during processing.

Generation of a Specific Marker to Discriminate Bacillus anthracis from Other Bacteria of the Bacillus cereus Group

  • Kim, Hyoung-Tai;Seo, Gwi-Moon;Jung, Kyoung-Hwa;Kim, Seong-Joo;Kim, Jee-Cheon;Oh, Kwang-Geun;Koo, Bon-Sung;Chai, Young-Gyu
    • Journal of Microbiology and Biotechnology
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    • v.17 no.5
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    • pp.806-811
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    • 2007
  • Bacillus anthracis is a soil pathogen capable of causing anthrax that is closely related to several environmental species, including B. cereus, B. mycoides, and B. thuringiensis. DNA homology studies showed that B. anthracis, B. cereus, B. mycoides, and B. thuringiensis are closely related, with a high sequence homology. To establish a method to specifically detect B. anthracis in situations such as environmental contamination, we initially performed RAPD-PCR with a 10-mer random primer and confirmed the presence of specific PCR bands only in B. anthracis species. One region specific for B. anthracis was cloned and sequenced, and an internal primer set was designed to amplify a 241-bp DNA fragment within the sequenced region. The PCR system involving these specific primer sets has practical applications. Using lyses methods to prepare the samples for PCR, it was possible to quickly amplify the 241-bp DNA segment from samples containing only a few bacteria. Thus, the PCR detection method developed in this study is expected to facilitate the monitoring of environmental B. anthracis contamination.

Substantial Evidences Indicate That Inorganic Arsenic Is a Genotoxic Carcinogen: a Review

  • Roy, Jinia Sinha;Chatterjee, Debmita;Das, Nandana;Giri, Ashok K.
    • Toxicological Research
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    • v.34 no.4
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    • pp.311-324
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    • 2018
  • Arsenic is one of the most toxic environmental toxicants. More than 150 million people worldwide are exposed to arsenic through ground water contamination. It is an exclusive human carcinogen. Although the hallmarks of arsenic toxicity are skin lesions and skin cancers, arsenic can also induce cancers in the lung, liver, kidney, urinary bladder, and other internal organs. Arsenic is a non-mutagenic compound but can induce significant cytogenetic damage as measured by chromosomal aberrations, sister chromatid exchanges, and micronuclei formation in human systems. These genotoxic end points are extensively used to predict genotoxic potentials of different environmental chemicals, drugs, pesticides, and insecticides. These cytogenetic end points are also used for evaluating cancer risk. Here, by critically reviewing and analyzing the existing literature, we conclude that inorganic arsenic is a genotoxic carcinogen.

Effects of Inorganic Coagulants on Sizing and Contamination in Newsprint Mill (무기 응결제가 신문용지의 사이즈도와 공정오염에 미치는 영향)

  • Lee, Tai Ju;Seo, Jin Ho;Lee, Kwang Seob;Jeong, Sung Hyun;Ryu, Jeong Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.3
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    • pp.40-46
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    • 2015
  • For some Korean newsprint mill, addition level of aluminum sulfate has been reduced because sulfur from aluminum sulfate has detrimental effect on the efficiency of anaerobic water treatment. At this moment, an unexpected decrease in sizing degree of TMP mixed newspaper was occurred. The phenomena means that hydrophobic substance usually originated from TMP cannot be fixed on the paper. This study focused on effect of alum and PAC on sizing of paper and contamination. Also, substitutability of PAC was discussed as a possible alternatives of aluminum sulfate under anaerobic condition of water treatment. Evaluation of sizing degree and pitch deposit potential were performed at the varied addition level of PAC and aluminum sulfate. Hydrophobic substance mainly derived from TMP could be fixed on the surface of fiber by PAC. Fines retention was not changed by replacing aluminum sulfate with PAC. Additionally, fixing of hydrophobic substance without excessive agglomeration can be enhanced by PAC with low molecular weight. Consequently, sizing degree of newspaper and contamination of recycling process of ONP can be controlled by low molecular weighted PAC.