• Journal of Soil and Groundwater Environment
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• v.23 no.5
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• pp.37-44
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• 2018

Soil trace elements and their bioaccumulation in agricultural products have attracted widespread concerns, yet the crop uptake characteristics of trace elements in different soil-plants systems have been rarely investigated. Experiments were carried out to investigate the effect of soil properties on trace element concentrations in cabbage and radish. Soil pH and total organic matter were major factors influencing trace elements transfer from soil to vegetables. Inclusion of other soil properties in the stepwise regression analysis improved the regression models for predicting trace element concentrations. Consideration of other soil properties should be taken into account for more precise prediction of trace element concentrations in the two vegetables, which could help quantitatively evaluate the ecologic risk of toxic trace elements accumulation in crops.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1533-1539
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• 2007

It is mainly due to the toxic gases, produced from the material combustion, threatens human body in case of urban railway car like subway which passes through underground tunnel. In the field of railway industry, fire accidents was not frequent but occurs in each country and, the causes was investigated. The advanced country established the test standard (e.g., BS, EN) to measure the toxic gases quantitatively and, have applied to enhance the fire safety of railway car. We must also follow the procedures to use gangway material for railway car as stated the Safety regulation for the urban railway car. In this study, various gangway materials(silicon, synthtic rubber, soaltapulin) are used to investigate element of toxic gases when the fire occurs. The amount of toxic gases measured from the ISO 5659 chamber using cone heater was measured and compared the results for each materials.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.778-784
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• 2017

We investigated the possibility of a bio-monitoring system for predicting toxic dinoflagellates (Genus Alexandrium) by the measuring shell valve movements(SVMs) of Pacific oyster, Crassostrea gigas (Mollusca: Bivalvia) using the Hall element sensor. We then described the SVMs of Pacific oyster exposed to the toxic algae under laboratory conditions. Pacific oyster used for experiment were fed Isochrysis galbana until they stabilized and kept under hunger conditions for three days to prevent the influence of food before the experiment. Pacific oyster were exposed to the toxic dinoflagellate, A. fundyense, and the potentially toxic dinoflagellate, A. affine. When Pacific oyster were exposed to A. fundyense, SVMs increased over 10 times/hr at low cell densities of 20 cells/mL. SVMs increased again at $14.1{\pm}5.7times/hr$ at 500 cells/mL, and $27.9{\pm}11.1times/hr$ at the high cell density of 5,000 cells/mL. However, in the presence of A. affine, SVMs increased at $6.7{\pm}3.9times/hr$ until 300 cells/mL, while they increased greatly to $15.3{\pm}10.8times/hr$ at 1,000 cells/mL. The SVMs of Pacific oyster indicated differences depending on species for toxic dinoflagellates. Therefore, the SVMs of Pacific oyster could be useful for A. fundyense, but would bedifficult to apply for A. affine.

• Economic and Environmental Geology
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• v.33 no.4
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• pp.273-282
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• 2000

In order to investigate the extent and degree of arsenic and heavy metal contamination and the bioavailability of toxic elements around the abandoned mine in Korea, an environmental geochemical survey was undertaken in the Daduk mine. After appropriate preparation, tailings, soil, stream sediment, crop plant and fingernail samples were analysed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-MS. Elevated levels of 8,782 mg/kg As, 8.3 mg/kg Cd, 489 mg/kg Cu, 3,638 mg/kg Pb and 919 mg/kg Zn were found in tailings from the Daduk mine. These significant concentrations can impact on soils and sediments around the tailing ponds. Mean concentrations of As, Cd, Pb, Cu and Zn in soils are significantly higher than those in world average soil, especially for As and Pb. Element concentrations in sediments decrease with distance from the tailing ponds due to a dilution effect by the mixing of uncontaminated sediments. Arsenic and Cd are elevated in rice grains and stalks, and Cu and Zn concentrations in chinese cabbage, sesame and bean leaves are higher than the upper limit values for normal plant. Arsenic concentration in fingernails of farmers are higher than the normal level with a maximum value of 1.5 mg/kg. The post-ingestion bioavailability of toxic heavy metals in some paddy and farmland soils has been also investigated using the SBET (simple bioavailability extract test) method. The method utilises synthetic leaching fluids closelyanalogous to those of the human stomach. The quantities of As, Cd, Cu, Pb and Zn extracted from paddy soils after 1 hour indicated 15.9, 65.4, 46.2, 39.4 and 29.4% bioavailability, respectively and for farmland soils, 12.4, 26.0, 31.2, 29.3 and 19.4% bioavailability, respectively. The results of the SBET indicate that regular ingestion of soils by the local population could pose a potential health threat due to long-term toxic element exposure.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.1
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• pp.31-40
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• 2001

Legal permissible limit of herbal drugs metal level in Korea is define 'less 30.0ppm in total(except mineral drugs)' including Pb Hg Cd As Cr Ni etc. This limit has a lot of problems in several factors, that is, not divide hazard and essential elements, not consider high and low toxic effect in each metal, not calculate dose-response relationship and average health behavior in Korean etc. As a that result, It has strong limits and weakness in the basic toxicology and Oriental medicine. To improve and correct these factors, We need to several new approach as like below. It must be radical study following problems in short and middle-long period in the future, toxic metal and essential element must be divide to basic toxicology and also be diverse toxic effect. But mineral drugs that included a amount of severe toxic metals is being used as active prescription drug until now. If toxic, safety and side-effect of metals will be considered, mineral drugs must prohibit instantly or use at least after examined toxic effect. But one of the most important things about herbal drugs contamination, all people and department (government, farmer and trader, oriental medicine doctors and association) will be participate cooperative and collection for preventive or the least contamination in herbal drugs.

• Economic and Environmental Geology
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• v.31 no.2
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• pp.111-125
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• 1998

Dispersion, migration and enrichment of environmental toxic elements from the Samkwang Au-Ag mine area were investigated based upon major, minor and rare earth element geochemistry. The Samkwang mine area composed mainly of Precambrian granitic gneiss. The mine had been mined for gold and silver, but closed in 1996. According to the X-ray powder diffraction, mineral composition of stream sediments and soils were partly variable mineralogy, which are composed of quartz, orthoclase, plagioclase, amphibole, muscovite, biotite and chlorite, respectively. Major element variations of the host granitic gneiss, stream sediments and soils of mining and non-mining drainage, indicate that those compositions are decrese $Al_2O_3$, $Fe_2O_3$, MgO, $TiO_2$, $P_2O_5$ and LOI with increasing $SiO_2$ respectively. Average compositional ranges (ppm) of minor and/or environmental toxic elements within those samples are revealed as As=<2-4500, Cd=<1-24, Cu=6-117, Sb=1-29, Pb=17-1377 and Zn=32-938, which are extremely high concentrations of sediments from the mining drainage (As=2006, Cd=l1, Cu=71, Pb=587 and Zn=481 ppm, respectively) than concentrations of the other samples and host granitic gneiss. Major elements (average enrichment index=6.53) in all samples are mostly enriched, excepting $SiO_2$, $Na_2O$ and $K_2O$, normalized by composition of host granitic gneiss. Rare earth element (average enrichment index=2.34) are enriched with the sediments from the mining drainage. Minor and/or environmental toxic elements within all samples on the basis of host rock were strongly enriched of all elements (especially As, Br, Cu, Pb and Zn), excepting Ba, Cr, Rb and Sr. Average enrichment index of trace elements in all samples is 15.55 (sediments of mining drainage=37.33). Potentially toxic elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) of the samples revealed that average enrichment index is 46.10 (sediments of mining drainage=80.20, sediments of nonmining drainage=5.35, sediments of confluent drainage=20.22, subsurface soils of mining drainage=7.97 and subsurface soils of non-mining drainage=4.15). Sediments and soils of highly concentrated toxic elements are contained some pyrite, arsenopyrite, sphalerite, galena and goethite.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.271-276
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• 1999

미국을 비롯한 선진국들은 이미 휘발성 유기화합물(volatile organic compounds) 과 독성 중금속(toxic metals)을 비롯한 유해 대기오염물(hazardous air pollutants)에 대해 ATEOS (Airborne Toxic Element and Organic Species), TEAM(Total Exposure Assessment Measurement) 연구등의 대규모 연구를 통하여 인체에 미치는 영향이 가장 큰 물질군이 휘발성 유기화합물임을 밝혀낸 바 있다. (중략)

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.5
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• pp.338-343
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• 2004

In general, the insulation and protective sheaths on electrical conductors are made of combustible substances like PVC, natural or synthetic rubbers, and other organic or synthetic materials. When an electrical fire starts due to overheating of conductors/joints or sparking/arcing, the first thing to ignite is usually the insulation on the cables. When the insulation bums, the produced fumes are very toxic. To solve the problem, we have surely need the fire resistance cable that doesn't bum in a high temperature and emit toxic fume for operating a disaster prevention installation. In this paper, we have simulated the thermal analysis for the fire resistance cable according to the values of current in a overload and a short, and the values of outside flame with the fire resistance cable of the L's company product(600 V, FR-8 : Four Core) using the finite element method(Flux2D).

• Journal of the Korean Wood Science and Technology
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• v.13 no.2
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• pp.35-44
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• 1985

The purposes of this study were, first, to investigate retention levels of toxic elements and oxide individual plies for each panel and, second, to examine disproportioning of individual toxic elements Thirty five water gum plywood panels were treated with a copper-chromium-arsenic preservative (CCA) by the soaking process as the treament time were applied. Such individual plies at a distance of 2.5cm, 7.5cm from the edge were assayed for CuO, $CrO_3$, and $As_2O_5$ on the basis of copper, chromium and arsenic content by Atomic Absorption Spectrophotometry. In these experiments, 12mm thickness plywood panels made of water gum, which were selling, were selected for the preservative treatment. Treating solutions were prepared for 10%, dilute solution of copper-chromium-arsenic preservative and then 1, 3, 6, 12 and 24 hours soaking trements in CCA preservative were applied. The results obtained are as follows: 1. The retention of total oxide in the face and back plies (1+7) retained more than the retention of total oxide in the other plies. The total oxide retention for the individual plies except the face and back plies (1+7) was showed in the following orders; cross plies (3+5), cross plies (2+6), core ply (4). 2. The retentions of total oxide increased as the increase of treatment time. The CCA treated plywood retained high levels of total oxide retention in the face and back plies (1+7). 3. All the retentions in the face and back plies (1+7) is over 5Kg/$m^3$, New Zealand Timber Preservation Standards Specification, and after 6 hours, the retentions in the cross plies (3+5) is over 4. The relative penetration of copper, chromium, and arsenic were not affected by the treatment time. The proportion of arsenic decreased in relation to both copper and chromium and the proportion of copper increased in relation to both chromium and arsenic. 5. A disproportioning of copper, chromium occurred with longer distance from edge, and with longer distance from edge the leachability resistance of CCA treated specimens decreased. After 6 hours (soaking time), the proportion of active elements at a distance of 2.5cm from the edge was consistent. And after 24 hours-soaking, the proportion of active elements at a distance of 7.5cm from the edge was consistent.

• Analytical Science and Technology
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• v.12 no.4
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• pp.346-353
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• 1999

For the non-destructive multi-elemental analysis of environmental and biological materials, instrumental neutron activation analysis (INAA) was applied for the determination of toxic and trace elements in a set of three Algae samples provided by the International Atomic Energy Agency (IAEA). The analytical quality control was evaluated by comparing the analytical results of two standard reference materials of the National Institute of Standards and Technology (NIST); Oyster Tissue (SRM 1566a) and Citrus Leaves (SRM 1572). According to given analytical procedure, the concentration of 15-25 elements including spiked elements such as As, Cd, Cr and Hg in Algae samples were determined. To identify and validate these results, a data intercomparison program using more than 35 analytical methods in 150 laboratories was carried out and the estimated statistical data are summarized. Result of INAA is favorable, therefore, it is illustrated that can be applied for routine analysis of essential and toxic elements in algae samples as well as analytical quality assurance.