• Title/Summary/Keyword: Permissible limits

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Problems of Legal Permissible Limit in Metal Level of Herbal Drugs Using Current Korea (현행 한국의 한약재 중금속기준개정 필요성 고찰)

  • Lee Sun-Dong;Park Kyung-Sik
    • 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.

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Analysis of Variability Factors in Establishing Pesticide Residue Limits on Food Crops (농산물중 농약잔류 허용기준 설정시의 변이계수 분석)

  • Lee, Mi-Gyung;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.492-497
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    • 2005
  • In establishing legal limits of pesticide residues, various default values are employed to compensate for unavoidable variability in data. Because permissible errors in residue analysis reach ${\pm}30-40%$ RSD, maximum residue limits (MRLs) follow geometric progression. According to 5-yr period JMPR reports, variability factor (ratio of highest to median values) in field residue trials was 3.8-fold in 486 crop-pesticide combinations and round-up effort from highest residue to MRL was 1.5-fold, whereas regulatory margin (ratio of MRL to highest residue) used in Korea was 4.8-fold in 822 crop-pesticide combinations; Korean MRLs will be set at higher levels as compared with Codex limits if these margins are employed. Validation studies to compare and harmonize Korean and Codex MRLs of pesticide residues on food crops should be undertaken.

Study on Odor From Gestating Sow Barns and Boundary Area (양돈장의 임신돈사와 부지경계에서 발생하는 악취 연구)

  • Jeong, J.W.;Park, K.H.;Heu, M.Y.;Choi, D.Y.;Lee, M.J.;Gang, H.S.
    • Journal of Animal Environmental Science
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    • v.15 no.2
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    • pp.107-114
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    • 2009
  • Civil appeals on odor from swine barn have been increasing. This study was conducted to compile basic data of odor from swine barns as civil appeals on odor have been increasing. Odor was monitored from two gestating sow barns and the boundary of those barns in Suwon and Hwaseong city from June to November, 2008. Mean ammonia concentration measured at the boundary of A piggery in Suwon city was 0.9 ppm with occasional breaks of permissible limit (1.0 ppm). Mean concentrations of hydrogen sulfide and methyl mercaptan were 0.37 ppb and 0.01 ppb, which were lower than permissible limits of 20 ppb and 2 ppb, respectively. Mean ammonia concentration was 3.22 ppm and was maintained under 5.0 ppb. Ammonia concentration had increased since November when the barns were closed. Hydrogen sulfide and methyl mercaptan were lower than the permissible limits. Mean ammonia concentration measured at the boundary of B piggery in Hwaseong city was 16.3 ppm and steep increase of concentration was monitored after October when the barn was sealed up. Hydrogen sulfide and methyl mercaptan were 26.66 ppb and 7.45 ppb, respectively. In appropriate ventilation and raising environment would cause high ammonia concentration in swine barns. Emitted ammonia from barns and composting facilities were mixed, which would cause higher ammonia concentration on the boundary of barns. Hence improvement of raising environment, rapid manure treatment, and correct use of microbial preparation would be needed.

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Solidification and Leaching Characteristics of Cyclone Ash from Industrial Incineration Plant

  • Lee, Dong-Choon;Kim, Young-Ju
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.10 no.S_2
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    • pp.89-95
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    • 2001
  • The solidification and leaching characteristics of cyclone ash collected from an industrial incineration plant were investigated. Cement and calcium hydroxide were used as the solidifying materials. The leaching characteristics of the solidified cyclone ash were found to vary depending on both the quantitative and the qualitative aspects of the solidifying materials. Except for copper and lead, all the heavy metal ions in the leachate of the solidified material composed of 10~20 % cement or 10~20 % calcium hydroxide were found to be within their standard limit. Moreover, all the heavy metal ions were also observed to be within satisfactory limits in the leachate obtained from the solidified material composed of 30 % cement or 30 % calcium hydroxide. Therefore, to satisfy the standard compressive intensity and permissible limits of heavy metal ions leached from solidified material, it would appear that a 30 % proportion of either additive in the solidification product can meet the required standard for the leachate. The cost of solidifying cyclone ash per ton for ash-30 % cement and ash-30 % lime was calculated as 26,750 and 26,070 won, respectively. Accordingly, significant reduction in the waste toxicity and mobility as well as an improvement in the engineering properties of the solidified products were successfully achieved.

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Water Quality Impact Assessment in Korea - Comparing with the Integrated Control of Pollutant-Discharging Facilities - (수질분야 환경영향평가의 개선방안 - 환경오염시설의 통합관리와 대비하여 -)

  • Lee, Jong Ho;Cho, Jae Heon
    • Journal of Environmental Impact Assessment
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    • v.26 no.5
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    • pp.331-343
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    • 2017
  • The important changes in water environment management in Korea can be summarized as the enactment of Act on the Integrated Control of Pollutant-Discharging Facilities. Therefore water quality impact assessment should be reexamined and be revised. This study examines the present water quality impact assessment items (permissible discharge limits, standards for effluent water quality including Total Pollutant Load Management System) and considers the land use regulation for water quality conservation and NVZs(Nitrate Vulnerable Zones of EU and England). It also considers lately adopted standards(maximum discharge standards, permissible discharge standards, and marginal discharge standards etc) based on Act on the Integrated Control of Pollutant-Discharging Facilities and then compares Korean BAT and its counterpart control technology of U.S.A. And it also compares the items of water quality impact assessment with those of Integrated Control of Pollutant-Discharging Facilities, based on EIS reporting items. This study suggests five improvement measures for water quality impact assessment. First reflection of discharge impact analysis on impact prediction and assessment, second reflection of permissible discharge standards on agreed standards in the EIA procedure, third, reflection of diversified BAT on mitigation measures in the EIA procedure, forth introduction of land use regulation such as NVZs, finally strengthening linkage between water quality items and land use items etc.

A proton induced X-ray emission (PIXE) analysis of concentration of major/trace and toxic elements in broiler gizzard and flesh of Tehsil Gujar Khan area in Pakistan

  • Nadeem, Khawar;Hussain, Javaid;Haq, Noaman Ul;Haq, A. Ul;Akram, Waheed;Ahmad, Ishaq
    • Nuclear Engineering and Technology
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    • v.51 no.8
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    • pp.2042-2049
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    • 2019
  • Ten gizzard and three flesh samples of the broiler were collected from different locations in Tehsil Gujar Khan District Rawalpindi, Pakistan. The samples were dried, crushed and ground. Pellets were prepared by pressing the powder of the samples and that of the Bovine liver 1577c reference material obtained from NIST, USA. Proton induced X-ray emission (PIXE) installed at National Center for Physics, Islamabad, Pakistan has been used as a reliable and improved technique to determine concentration of various major/trace and toxic elements e.g. S, Cl, K, Ca, Cl, Fe, Cu, Mn, Co, Zn, Ti, Cd, Ga, Cr, V and Ni, in the Gizzard and Flesh samples of the broiler. The concentrations of all the detected elements in the samples are statistically significant. The certified and measured values of the elements in the reference material were in agreement with each other within a deviation of 7%. S, Cl, K and Ca are within tolerable limits and are good for human consumption. Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn were more than the acceptable limits of World Health Organization, WHO whereas Ga, As, Sn, Sb and Pb are not detected in most of the samples.

Contribution of Water Chemistry in Initiation of Some Accelerated Corrosion Processes in CANDU-PHWR Primary System

  • Pirvan, Ioana;Radulescu, Maria;Fulger, Manuela
    • Corrosion Science and Technology
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    • v.7 no.2
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    • pp.85-91
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    • 2008
  • By operation in aqueous environment at high temperature and pressure, the structural materials from Primary Heat Transport System (PHTS) cover with protective oxide films, which maintain the corrosion rate in admissible limits. A lot of potential factors exist, which conduct to degradation of the protective films and consequently to intensification of the corrosion processes. The existing experience of different nuclear reactors shows that the water chemistry has an important role in integrity maintaining of the protective oxide films. To investigate the influence of water chemistry (pH, O2 dissolved, $Cl^-$, $F^-$) on corrosion of some structural materials (carbon and martensitic steel, Zr and Ni alloys) and to establish the maximum permissible values, corrosion experiments by static autoclaving and electrochemical methods were performed. The experimental results allowed us to establish the contribution of the water chemistry in initiation and evolution of some accelerated corrosion processes.

A 2.4 GHz 802.11b Throughput Estimation In a Noisy Environment Using an Experimental Noise Parameter

  • Hur Min-Ho;Lim Sung-Jin;Kwon Sewoong;Yoon Young-Joong
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.61-65
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    • 2005
  • In this paper, a numerical permissible disturbance model is proposed to preserve a throughput performance of a 2.4 GHz wireless LAN service. The model is composed of two parameters, a peak value and a time rate of noise signal. The model parameters are experimentally determined from an APD parameter measurement. The APD parameter is measured by using the APD measurement method which is recommended from CISPR/A/447/CD.

Gaseous by-products from the TiO2 Photocatalytic Oxidation of Benzene

  • Han, Sang-Wook;Lee, Jin-Hong;Kim, Jin-Seog;Oh, Sang-Hyub;Park, Young-Kwon;Kim, Hyun-Ook
    • Environmental Engineering Research
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    • v.13 no.1
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    • pp.14-18
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    • 2008
  • Photocatalytic oxidations of benzene gas using the closed system (batch reactor) were induced to determine its by-products and investigate the effect of humidity and oxygen concentration on their generation. The study was able to identify 11 gaseous by-products: 2-methylpropene, acetaldehyde, acetone, pentane, methylcyclobutane, methylcyclopentane, cyclohexane, 2,3-dimethylbutane, 2-methylpentane, 3-methylpentane, and hexane. All the by-products were saturated hydrocarbons, which are less toxic than benzene and were probably formed through hydrogenation reaction on the photocatalytic surface. The photocatalytic oxidation of benzene under higher humidity produced less by-products. However, the amount of acetone released increased with higher humidity and oxygen concentration.

Voltage Regulation Method at the Power Distribution System interconnected with DSG System (분산형전원이 연계된 배전계통의 전압조정에 관한 연구)

  • Choi, Joon-Ho;Chu, Dong-Wook;Kim, Jae-Chul;Hwang, Chi-Woo
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.250-252
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    • 1997
  • This paper deals with voltage regulation at the power Distribution system interconnected with DSG. Modern distribution substation adopt LDC method as the voltage regulation method to deliver suitable voltages to many customers. However, the operations of DSG interconnected with distribution system, the customers' voltage violate the permissible voltage limits. Therefore, to deliver suitable voltage to many customers at the distribution substation, an advanced voltage regulation method is required. In this paper, the on line realtime MLDC (Multiple Line Drop compensation) method, considered daedband and hysterical tap changing of the ULTC, is proposed. The result from a simulation study shows that the proposed method can be practical applications for the voltage regulation at the distribution system interconnected with DSG and unbalanced load pattern among feeders.

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