• Title/Summary/Keyword: toxic chemical

Search Result 1,044, Processing Time 0.026 seconds

A Study on Risk Analysis of Manufacturing Process Using the Bow-Tie Method (Bow-Tie기법을 이용한 제조공정의 위험성평가 연구)

  • Tae, Chan Ho;Lee, Heon Seok;Byun, Chul Hyun;Yang, Jae Mo;Park, Chulhwan;Ko, Jae Wook
    • Journal of the Korean Institute of Gas
    • /
    • v.17 no.3
    • /
    • pp.33-38
    • /
    • 2013
  • The chemical industries have used large amounts of chemicals. If an accident occurs, it caused physical and human damage. We intended to investigate risk assessment for the prevention of accidents. The risk assessment by HAZOP technique has been applide to major chemical industries, and that result has been utilized efficiently. In this study, we analyzed Bow-Tie and HAZOP technique, and risk assesment was performed by Bow-Tie on toxic material process. As a result, the risk that can not be found in the risk assessment of the other is derived, and improvements of 14 to remove the dangers derived. Bow-Tie risk assessment is suitable to derive the applicability of risk factors in the field and to establish the improvement measures.

Metal-Free Oxidation of Alcohols to Their Corresponding Carbonyl Compounds Using NH4NO3/Silica Sulfuric Acid

  • Zarei, Amin
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.7
    • /
    • pp.2149-2155
    • /
    • 2012
  • A metal-free and efficient procedure for the oxidation of alcohols into the corresponding carbonyl compounds has been described using ammonium nitrate in the presence of silica sulfuric acid under mild and heterogeneous conditions. The use of non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are among the advantages of this method.

PLR (Plastic Lithium Rechargeable) Batteries using Nanoscale Materials : A Convenient Source of Electrical Energy for the Future?$\dag$

  • G. Campet;N. Treuil;A. Poquet;S. J. Hwang;C. Labrugere;A. Deshayes;J. C. Frison;J. Portier;J. M. Reau;J. H. Choy
    • Bulletin of the Korean Chemical Society
    • /
    • v.20 no.8
    • /
    • pp.885-892
    • /
    • 1999
  • This communication describes the synthesis of : (i) non-toxic and low cost nanocrystalline electrode materials, which can be prepared advantageously at low temperature ; (ii) highly conductive electrolyte membranes formed by the nano-encapsulation within a poly(acrylonitrile)-based polymer matrix of a solution of LiPF6 in organic solvants. The performances of rechargeable PLR (Plastic Lithium Rechargeable) batteries using the above mentioned components are presented.

Changes in the Ecological Toxic Effects of the Contaminated Sediment of Singapore after Treatment (싱가포르 오염준설토 정화 후 생태 독성 변화)

  • Jho, Eun Hea;Yun, Seong Ho;Hwang, Sun Kyung;Lee, Sung Jong;Kim, Hongseok;Chae, Heehun
    • Journal of Soil and Groundwater Environment
    • /
    • v.22 no.5
    • /
    • pp.82-88
    • /
    • 2017
  • Contaminated sediment can be treated in order to reuse the treated sediment. Even though the chemical criteria are satisfied, the treated sediment could still impose toxic effects. Therefore, this study investigated the changes in the ecological toxic effects of the contaminated sediment from the J region in Singapore after treatment. The contaminated sediment was subject to sequential soil washing and thermal treatment, followed by pH neutralization. Toxic effects of the contaminated and treated sediments were determined by using Vibrio fischeri ($Microtox^{(R)}$), Triticum aestivum (wheat), and Eisenia foetida (earthworm). After treatment, the concentrations of total petroleum hydrocarbons and heavy metals were decreased by 98% and 59-93%, respectively, and satisfied the Industrial Maximum Values of the Dutch Standard, which were used as the remedial goal. The bioluminescence reduction of V. fischeri decreased significantly, and the earthworm survival increased from 0% to 90% after treatment. The germination rate increased from $0{\pm}0%$ to $75{\pm}13%$ after treatment, but the treated sediment may need additional treatment such as nutrient addition for better plant growth. Overall, this study showed that the treatment of the contaminated sediment satisfactorily removed mixed contaminants, and this led to reduction in toxic effects, suggesting improved potentials for reuse of the treated sediment.

Some Toxic Heavy Metals Transferring Rates to Decoction of Five Most Generally Adopting Herbal Medicinal Prescriptions (다섯 가지 다용한약처방의 전탕 전후 유해 중금속 이행률 조사)

  • Kim, Kee Dong
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.19 no.3
    • /
    • pp.103-113
    • /
    • 2015
  • Objective : Five most generally adopting basic oriental prescriptions (yookmijihwangtang, ojeoksan, sipjeondaebotang, samultang, bojoongikgitang) samples were collected from 10 oriental hospitals nationwide and the transferring ratio to aqueous phase (TRAP) were calculated. Method : The samples are grounded evenly and the decocted at $120^{\circ}C$ for 12 min on hot plate and then filtered. The concentrations of As, Cd, Co, Cr and Pb in before and after decoction were measure by ICP/MS and the TRAPs were calculated. Results : The concentrations of As, Cr and Pb in the ground samples before decoction were all below criteria level, and TRAP values were also very low (<10%). For Cd, although some ground samples before decoction showed relatively high concentration level compare to the criteria level, because of their low TRAP (~3%), the actual concentrations in the decoction were quite low compare the criteria level. The Co's concentrations in the ground samples before decoction were all relatively low level. However, the TRAP of Co was astonishingly high value of around 40% average. Conclusion : The toxic heavy metal concentrations in the decoction were very low compare to the criteria level. The TRAPs are less than <10% except Co. The toxic heavy metals in the prescriptions are mainly remained in the residue and the only very small fraction may transferred to the decoctions. Therefore the toxicity of the oriental herbal medicine about the toxic heavy metal may be overstressed. The Co's TRAP turned out to be quite high value (40% average). Since the criteria level wes not established yet, the safety of decoctions according to Co was not fully confirmed.

Inhaled Formaldehyde Induces Bone Marrow Toxicity via Oxidative Stress in Exposed Mice

  • Yu, Guang-Yan;Song, Xiang-Fu;Liu, Ying;Sun, Zhi-Wei
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.13
    • /
    • pp.5253-5257
    • /
    • 2014
  • Formaldehyde (FA) is an economically important chemical, and has been found to cause various types of toxic damage to the body. Formaldehyde-induced toxic damage involves reactive oxygen species (ROS) that trigger subsequent toxic effects and inflammatory responses, which may increase risk of cancer. Therefore, in the present study, we aimed to investigate the possible toxic mechanism in bone marrow caused by formaldehyde. In accordance with the principle of randomization, the mice were divided into four groups of 6 mice per group. One group was exposed to ambient air and the other three groups were exposed to different concentrations of formaldehyde (20, 40, $80mg/m^3$) for 15 days in the respective inhalation chambers, 2h a day. At the end of the 15-day experimental period, all mice were killed. Bone marrow cells were obtained. Some of those were used for the determination of blood cell numbers, bone marrow karyote numbers, CFU-F, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content; others were used for the determination of mitochondrial membrane potential (MMP), cell cycle and Bcl-2, Bax, CytC protein expression. WBC and PLT numbers in median and high dose groups were obvious reduced, but there was no change on RBC numbers. There was also reduced numbers of bone marrow karyotes and CFU-F in the high dose group. SOD activity was decreased, but MDA content was increased. MMP and Bcl-2 expression were decreased with increasing formaldehyde concentration, while expression of Bax and Cyt C was increased. We also observed change in cell cycling, and found that there was S phase arrest in the high dose group. Our study suggested that a certain concentration of formaldehyde could have toxic effects on the hematopoietic system, with oxidative stress as a critical effect.

Studies on the Selective Toxicity of Insecticides for Rice Insect Pests between Some Dominant Rice Insect Pests and a Predatious Spider, Pirata subpiraticus (수도주요해충 및 포식성천적 황산적거미에 대한 살충제의 선택독성에 관한 연구)

  • Yoo J.K.;Kwon Y.W.;Park H.M.;Lee H.R.
    • Korean journal of applied entomology
    • /
    • v.23 no.3 s.60
    • /
    • pp.166-171
    • /
    • 1984
  • The present studies were conducted to investigate the relative toxicity of several insecticides to the rice insect pests and the predatious spider, Pirate subpiraticus. In laboratory test by topical application, BPMC and MIPC for the plant and leafhoppers were toxic to Nilaparvata lugens, but less toxic to Pirata subpiraticus. Other carbamate insecticides such as carbaryl, carbofuran, and MTMC showed highly toxic effect on P. subpiraticus as well as N. lugens. No organophosphates showed selective toxicity to P. subpiraticus. Thiocyclam, effective to Chilo suppressalis and Sesamia inferens, had highly good selective toxicity to P. subpiraticus. In case of insecticides for Nephotettix cincticeps, BPMC only had a little selective toxicity between N. cincticeps and P. subpiraticus. Organophosphate insecticides which had been reported to induce chemical resistance to N. cincticeps showed high $LD_{50}$ value to N. cincticeps. In pot trials, dust formulation was more toxic to P. subpiraticus than emulsifiable concentrate. It was more toxic to P. subpiraticus to increase number. of insecticide application.

  • PDF

Acute Toxicity Study of Recombinant Granulocyte-Macrophage Colony Stimulating Factor (LBD-005) in ICR mice

  • Kim, Hyoung-Chin;Song, Si-Whan;Cha, Shin-Woo;Shin, Chun-Chul;Ha, Chang-Su;Han, Sang-Seop
    • Biomolecules & Therapeutics
    • /
    • v.1 no.2
    • /
    • pp.270-274
    • /
    • 1993
  • The acute toxicity of a recombinant granulocyte-macrophage colony stimulating factor (code name: LBD-005) was evaluated in both sexes of ICR mice, 5~6 weeks old, by the oral, subcutaneous and intravenous routes of administration. Based on the results of the acute toxicity study, LBD-005 was not considered to induce any toxic effect on the mice in mortalities, clinical findings, body weights and gross findings. It is suggested that $LD_50$ values in mice would be >48 mg/kg in the oral route and >24 mg/kg in the subcutaneous or intravenous route.

  • PDF

Acute Toxicity Study of Recombinant Human Interferon ${\alpha}A$ (LBD-007) in ICR Mice

  • Kim, Hyoung-Chin;Song, Si-Whan;Cha, Shin-Woo;Shin, Chun-Chul;Ha, Chang-Su;Han, Sang-Seop
    • Biomolecules & Therapeutics
    • /
    • v.1 no.2
    • /
    • pp.266-269
    • /
    • 1993
  • The acute toxicity of a recombinant human interferon $\alpha$A (code name: LBD-007) was evaluated in both sexes of ICR mice, 5 weeks old, by the oral, subcutaneous and intravenous routes of administration. Based on the results, LBD-007 was not considered to induce any toxic effect on the mice in mortalities, clinical findigs, body weights and gross findings. It is suggested that LD$_{50}$ values in mice would be $>48{\times}10^8$ IU/kg in the oral, subcutaneous or intravenous routes.s.

  • PDF

Position/force Control using 6-axis Compliance Device for Chemical Coupler Assembly (케미컬 커플러 체결을 위한 순응장치를 이용한 위치/힘 동시제어)

  • Park, Shi-Baek;Kim, Han-Sung
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.25 no.5
    • /
    • pp.909-915
    • /
    • 2022
  • In this paper, a robot automation technology for chemical tank lorry unloading is presented. Handling chemical coupler between tank lorry and ACQC system may be hazardous or toxic to human operators, therefore robot automation is essential. Due to tight tolerance between couplers, even small pose error may result in very large internal force. In order to resolve the problem, compliance between male and female couplers should be introduced with 6-axis compliance device with F/T sensing. The proposed robot automation system consists of a collaborative robot, 6-ax is compliance device with F/T sensing, linear gripper, and robot vision. The position/force control algorithm and experimental results for assembling chemical couplers are presented.