• Title/Summary/Keyword: toxic pollutants.

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Measurement of Persistent Toxic Substances in Gosan, Jeju (제주도 고산에서의 미량독성 유해물질 측정)

  • 김영성;김진영;문길주;한진석;김영준;윤순창;김용표;강창희;권성안
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.77-78
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    • 2003
  • 2001년 5월 스톡홀름에서는 92개국이 DDT, 다이옥신 등 12개 잔류성 유기오염물질 (POPs, persistent organic pollutants)의 궁극적 소멸을 목표로, 배출 및 사용 저감을 위하여 유엔협약인 이른바 스톡홀름협약에 서명하였다. 이는 유럽에서 UNECE (United Nations Economic Commissions for Europe) 장거리 이동 대기오염 협약의 일환으로 1998년 6월 덴마크 오후스에서 체결된 POPs에 관한 의정서에 뒤이은 결과이다 1998년 6월 오후스에서는 POPs와 함께 수은, 카드뮴, 납 등 3개 중금속에 관한 의정서가 체결되어 중금속에 관한 향후 국제사회의 동향을 짐작케 하고 있다. (중략)

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Effects of Environmental Factors on Degradation of Aroclors by Gram-negative Bacteria (Gram 음성세균에 의한 Aroclor 분해에 미치는 환경요소의 영향)

  • 김치경;김문식
    • Korean Journal of Microbiology
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    • v.28 no.2
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    • pp.145-150
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    • 1990
  • The effects of environmental factors on degradation of Aroclor 1242 were investigated with four Gram-negative bacterial isolates. Their biodegradabilities of the Aroclor were well correlated to their growth rates on the Aroclor added as a sole carbon and energy source. The optimum concentration of the Aroclor for biodegradation of the substrate in MM2 medium was 0.5mg/ml in HK-100, HK-123, and MS-1003 strains, but 1 mg/ml in DJ-26 strain. The optimum temperature and pH were $30^{\circ}C$ and 7.0, respectively, for all the strains. On the basis of the results which the strain of DJ-26 showed the highest degradability of the Aroclor as well as the highest growth rate under the optimum environmental conditions, the bacterial isolate identified as Pseudomonas sp. was found to be a strain usable for treatment of the toxic and recalcitrant chemical pollutants, such as polychlorinated aromatic hydrocarbons.

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Preparation of Energetic Metal Particles and Their Stabilization (에너제틱 금속입자 제조 및 안정화 기술)

  • Lee, Hye Moon;Kim, Kyung Tae;Yang, Sangsun;Yu, Ji-Hun;Kim, Yong-Jin
    • Particle and aerosol research
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    • v.9 no.3
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    • pp.173-185
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    • 2013
  • Oxidations of metal generate large quantity of thermal and light energies but no toxic pollutants, so that metals with high calorific values, such as beryllium, boron, aluminum, magnesium, and lithium, are possible to be used as clean fuels instead of fossil fuels. However, they are so explosive due to very high oxidation rates that they should be stabilized by their surface passivation with oxides, organics and inorganics. For reasonable use of energetic metal particles as solid fuel, therefore, some detail information, such as thermal properties, preparation and passivation methods, and application area, of the energetic metals is introduced in this manuscript.

Identification of Ozone-induced Skin Damage and Screening of Antioxidant for Ozone (오존에 의한 피부손상 확인 및 이를 방어하는 피부 외용제 소재의 탐색)

  • 최신욱;김창수;정재형;김남경;한상화
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.39-51
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    • 2004
  • Ozone(O$_3$), one of best-known toxic air pollutant, act as a strong oxidant. It is possible that skins exposed to the air can be easily damaged by such oxidative air pollutants. Therefore, in the present study, anti-oxidative effects of natural product. on $O_2$ㆍ and ㆍOH were investigated by EPR. Ozone caused protein damage and lipid oxidation, in HaCaT and B16F10 leading ultimately to programmed cell death. It also reduced the level of antioxidant molecules including ascorbic acid and tocopherol in stratum comeum. However, antioxidants originated from natural products could protect skin from these products could protect skin from these oxidative damages. We concluded that eight natural extracts including Rosa davurica, Ligularia sibrica, Green tea acted as strong antioxidants against ozone.

탈질 조건에서 투과매질 내 미생물 성장에 관한 연구

  • 최영화;오재일;배범한
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.09a
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    • pp.366-369
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    • 2002
  • Subsurface biobarrier technology has potential applications to contain contaminated groundwater and/or to degrade toxic pollutants in groundwater. Most biobarrier studies were conducted under aerobic condition, however there were several obstacles to make aerobic condition. Thus, In this study, we examined biobarrier formation under denitrifying condition by using nitrate as an electron acceptor. Experiments were performed with a sand column inoculated with activated sludge from the nearby WWTP. The substrate medium was pumped to the sand column in an upflow mode. During the low substrate loading rate period, the extent of reduction rate in hydraulic conductivity was found similar throughout the column, and permeability became relatively stable after couple of days. However, during the high substrate loading rate period, the column demonstrated a gradient of permeability reduction, with the greatest reduction in sections nearest the column inlet. Rapid growth of microorganisms near the column inlet resulted in the unbalanced reduction of hydraulic conductivity throughout the sand column. As a result, at this denitrifying condition the thickness of biobarrier could be controlled by adjusting the medium conditions of microbial growth.

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A Study of Improvement on Collaboration Treatment Method of Electroplating Wastewater (도금폐수의 공동처리를 위한 공정개선에 관한 연구)

  • 이내우;최재욱;안병환
    • Journal of the Korean Society of Safety
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    • v.12 no.4
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    • pp.93-101
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    • 1997
  • A modified procedure for electroplating wastewater treatment using formaldehyde and hydrogen peroxide can destroy free cyanide. The representative diagram which is quite sensitive on reaction temperature is showed for this kinds of treatment. Principally free cyanide and some kinds of cyanide complex should be treated first, and then toxic heavy metals can be removed because cyanide component will be inhibited to remove other pollutants, if it is not destroyed perfectly. Formaldehyde and hydrogen peroxide are added in controlled amounts to cyanide treatment tank. Reasonable amounts of these chemicals are (HCHO/CN)=0.9 and ($H_2O_2/CN$)=1.1 in molar ratios, it is also variable on reaction temperature. Of course, actual treatment processes depending on plating material and chemical are good applicable, also to systematize operation manual for treating electroplating wastewater process, further works are desirable.

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호소 및 하천의 오염 저질토 sampling 방법 및 처리방안 연구

  • 최동호;배우근;최형주
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.115-119
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    • 2003
  • Pollutants from industry, mining, agriculture, and other sources have contaminated sediments in many surface water bodies. Sediment contamination poses a severe threat to human health and environment because many toxic contaminants that are barely detectable in the water body can accumulate in sediment at much higher levels, the purpose of this study was to make convenient sampling method and optimal treatment of sediment for water quality improvement in reservoir or stream based on an evaluation of degree of contamination. Results for analysis of S-reservoir sediments were observed that copper concentration of almost areas were higher than the regulation of soil pollution (50 mg/1) for the riverbed. S-stream sediments were observed that copper, arsenic and TPH concentration of almost areas were exceeded soil pollution concerning levels for factorial areas. We used Remscreen(version. 1.0) program which is contaminated soil recovery program to select optimal treatment method of contaminant sediments. The result was shown in the order of Thermal Calcination > Excavation, Retrieval and Off-site Disposal(comparative less then contaminant) > Low Temperature Thermal Desorption + Solidification/Stabilization.

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Disturbance in Testosterone Production in Leydig Cells by Polycyclic Aromatic Hydrocarbons

  • Oh, Seunghoon
    • Development and Reproduction
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    • v.18 no.4
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    • pp.187-195
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    • 2014
  • Polycyclic aromatic hydrocarbons (PAHs), which are ubiquitous in the air, are present as volatile and particulate pollutants that result from incomplete combustion. Most PAHs have toxic, mutagenic, and/or carcinogenic properties. Among PAHs, benzo[a]pyrene (B[a]P) and dimethylbenz[a]anthracene (DMBA) are suspected endocrine disruptors. The testis is an important target for PAHs, yet effects on steroidogenesis in Leydig cells are yet to be ascertained. Particularly, disruption of testosterone production by these chemicals can result in serious defects in male reproduction. Exposure to B[a]P reduced serum and intratesticular fluid testosterone levels in rats. Of note, the testosterone level reductions were accompanied by decreased steroidogenic acute regulatory protein (StAR) and $3{\beta}$-hydroxysteroid dehydrogenase isomerase ($3{\beta}$-HSD) expression in Leydig cells. B[a]P exposure can decrease epididymal sperm quality, possibly by disturbing the testosterone level. StAR may be a key steroidogenic protein that is targeted by B[a]P or other PAHs.

Performance Evaluation of Methodology for Personal Exposure Monitoring of ETS and VOCs in Non-occupational Environments (비작업장 환경에서의 ETS와 VOC에 대한 개인피폭량 측정 방법의 성능평가)

  • Baek Seong-Ok;Hwang Seung-Man;Mun Yeong-Hun;Kim Mi-Hyeon;Kim Seong-Ryeol;Choe Jin-Su
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.399-400
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    • 1999
  • From the scientific point of view, any regulation of the emissions of toxic air pollutants in general, and ETS or VOCs in particular, will inevitably be based on exposure levels and consequential health effects, data of this nature is still lacking for most of ETS and VOCs. In this context, the importance of personal monitoring measurements of ETS and VOCs in relation to risk assessment has been emphasized previously.(omitted)

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The Materials of Earth Friendly Architecture (친환경 건축물의 자재에 관한 연구)

  • Yoo, Ho-Chun;Lee, Young-A
    • Journal of the Korean Solar Energy Society
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    • v.23 no.4
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    • pp.81-88
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    • 2003
  • Earth friendly system is applied widely to industries for maintaining development. The declaration of earth friendly characteristic which is an indication of the total amount of energy in evaluation of earth friendly material is not easy to apply to building materials Therefore, Accurate standards about earth friendly materials are necessary. Earth friendly building materials should be considered in the fields of energy and resource consumption, changes in urban climate and resident health, etc. Among these fields, energy and resource consumption has released toxic pollutants into the air, caused indoor moisture problems and exhausted resources continuously. Especially, moisture problem is an indicator of main factors of earth friendly characteristic. Timber, Soil. Cement Mortar and Charcoal are used to examine the sustainable properties of materials of moisture control. The result shows that wood, charcoal and soil is vivid in changes of moisture absorption and discharge in comparison with that of cement mortar.