• Title/Summary/Keyword: Toxic

Search Result 5,402, Processing Time 0.027 seconds

A Study on Definition and Classification System of Wastes (폐기물의 개념 및 분류체계에 관한 연구)

  • Hong, Dong-Hee
    • Journal of Environmental Policy
    • /
    • v.3 no.2
    • /
    • pp.113-137
    • /
    • 2004
  • The objective of this study is to introduce the definitions and classification methods of wastes in international agreements and legislations, examine the concept of wastes and their classification systems in Korea, and finally analyze and compare the concept of wastes in different countries for finding better solutions and suggestions. The study summarizes the concept of wastes as introduced in the Basel Convention, OECD, EU, US, and UK. First, each of the member countries adapt to the same concepts of wastes as defined in their international agreements; second, the intention of the wastes holder and the conditions of the wastes are considered at the same time when defining the concepts. Upon close examination of the classification of wastes systems as introduced in the Basel Convention, OECD, EU, US, and UK, the wastes are classified into toxic and non-toxic wastes according to the existence of poisonous substances. Therefore, it is classified as a toxic waste when any toxic substance on its list is included in the waste, while others are considered as a non-toxic waste if they don't contain poisonous substances. Secondly, in the UK, the matter of toxic or non-toxic wastes are classified, not according to the existence of the poisonous substances, but based on the generation of sources. In Korea, the concepts of wastes are divided into the two categories - a concept as defined in actual legislations and a concept in its translation. The Korean classification of the wastes include Wastes Management Act, amended in 1995, which stipulates that toxic substances should be managed in a special way as the designated wastes. It appears that the Act utilizes the classification method that classifies the wastes according to the existence of poisonous substance. Korea's concepts of wastes should be changed after recognition of the concepts in international agreement (Basel Convention, EU) and other foreign laws(US, UK) that consider subjective and objective standards at the same time when they define the concepts. Also, the development of technology in recycling and reuse of the wastes can remove the current absolute notion of the wastes so that it also should not be passed over. Also, because a classification structure of wastes has a close relationship with a disposal structure, its classification system should be fixed gradually to come up with the development of wastes disposal technology and its policy.

  • PDF

Soil Washing and Effluent Treatment for Contaminated Soil with Toxic Metals (유해원소로 오염된 토양 세척 및 세척수의 처리)

  • Yang, Jung-Seok;Hwang, Jin-Min;Baek, Kitae;Kwon, Man Jae
    • Korean Chemical Engineering Research
    • /
    • v.51 no.6
    • /
    • pp.745-754
    • /
    • 2013
  • This study evaluated the optimal soil washing conditions for toxic metals considering the removal efficiency of toxic metals from contaminated soils as well as from soil washing effluents. In the contaminated soils, As was the major contaminant and extracted by sodium hydroxide solution better than by sulfuric acid. However, in the case of the treatment of soil washing effluents, sodium hydroxide was less effective extractant because soil organic matter extracted by sodium hydroxide prevented the solid-liquid phase separation and toxic metal removal. In the treatment of soil washing effluents with sulfuric acid, toxic metals in the effluents were mostly precipitated at the pH above 6.5. In addition, granular ferric oxide (GFO) as an adsorbent enhanced the removal of As and Pb indicating that toxic metals in the washing effluents can be removed almost completely by the use of combined adsorption-neutralization process. This study suggests that soil washing techniques for toxic metals should be optimized based on the physical and chemical properties of the contaminated soils, the nature of chemical extractant, and the removal efficiency and effectiveness of toxic metals from the soils as well as soil washing effluents.

Geochemical Behavior, Dispersion and Enrichment of Environmental Toxic Elements in Coaly Metapelites and Stream Sediments at the Hoenam Area, up the Taecheong Lake, Korea (대청호 상류, 회남일대에 분포하는 탄질 변성니질암과 하상 퇴적물의 환경유해원소에 관한 지화학적 거동, 분산 및 부화)

  • Lee, Chan Hee;Lee, Hyun Koo
    • Economic and Environmental Geology
    • /
    • v.30 no.3
    • /
    • pp.209-222
    • /
    • 1997
  • The Hoenam area, up the Taecheong lake, composed mainly of low grade coal-bearing metapelites within the Ogcheon Supergroup. These coal formations are developed discontinuously several hundred meters and swelling from 10 to 300 cm along the host metapelites. Although the formations have been mined for coal, but already mined out, and the formations were higher content (mean value of 42 samples) of environmental toxic elements as As (13 ppm). Ba (1.81 wt. %), Cd (2 ppm), Cr (188 ppm), Cu (87 ppm), Mo (214 ppm), Pb (25 ppm), Sb (3 ppm), Se (12 ppm), U (55 ppm), V (2124 ppm) and Zn (234 ppm) than the host metapelites and the NASC. The Al, Ti, Mg, K and Na contents in stream sediments derived from the Hando and Bugook mine area were highly concentrations than the samples from the Samseongjeil mine area. The mean value (wt. %) of Fe (10.07), Mn (0.15), Ca (0.84), P (0.18) and Ba (0.77) influenced by the Samseongjeil mine were higher than the other mine drainage sediments. The mean content (ppm) of environmental toxic elements in drainage sediments from the Samseongjeil mine were taken As (2083), Cu (447), Mo (202), Ni (720), Pb (42), U (250), V (1070) and Zn (2632), which are extremely high concentrations against NASC and EPA. Characteristics of elemental behavior and dispersion of the all toxic elements are the same as increased with increasing U, V, and Cu. Rare earth elements in the sediments are enriched with LREE (La, Ce and Nd) from the drainage on strong concentration of toxic elements. The pH of stream water is neutral, but pH of the sediments ranged from 4.92 to 6.93 (mean 6.22), those are slightly acid in the Hando mine area. Major elements in the host rocks at the Hoenam area are mostly depleted especially Ca, excepting Ti and Ba, normalized with NASC. The sediments were highly enriched of Ti, Fe, Mg, Mn and Ba, but depleted of Al, K, Ca, Na and P on the basis of host rocks and NASC. Minor and environmental toxic elements in the host rocks were strongly enriched all elements (As, Cd, Mo, Se, D, V and Zn), excepting Co, Ni and Sr. Enrichment index (mean value) about toxic elements (As, Cr, Cu, Fe, Ni, Pb and Zn) of the sediments in this area have taken 41.35 (Hando mine drainage; 2.73, Samseongjeil mine drainage; 113.14 and Bugook mine drainage; 8.19), those are seriously contaminated by environmental toxic elements.

  • PDF

A Study on the Destruction or Removal Efficiency of Toxic Gas Reduction Facilities in Semiconductor and Display Industries (반도체 & 디스플레이 업종에서 사용되는 독성가스 저감시설의 처리효율 측정방법에 관한 연구)

  • Jang, Sung-Su;Han, Jae-Kook;Cho, Hyun-Il;Lee, Su-Kyung
    • Journal of the Korean Institute of Gas
    • /
    • v.21 no.6
    • /
    • pp.88-95
    • /
    • 2017
  • The usage of toxic gas in Korea is increasing in the development of high-tech industries such as semiconductors, displays and solar panels. The recent survey of domestic toxic gas consumption indicates an increase in annual average of 12.4 percent, but it is still focused on usage, and it is negligent in safety and treating the post. In September 2012, an accident occurred in Gu-mi involving hydrofluoric acid leak demonstrates the absence of safety management. Due to the incident, the government, industry and academia have been interested in chemical substances(toxic gas), and the government-led safety management has been established and implemented, but there are still a lot of safety blind spots. The purpose of this study is to develop effective measurement methods for the destruction or removal efficiency of gaseous materials emitted from the Scrubber used in the semiconductor and display industries. Also, this study demonstrated how toxic gas facilities can be applied without error by verification test for the measurement method guideline of the destruction or removal efficiency of the green-house gas reduction facility in the semiconductor and display industries used by the National Institute of Environmental Research and the UNFCCC, and suggested the differentiated measurement methods for toxic gas reduction facilities, and the third party certification for safety facilities is needed to prevent toxic gas accidents.

Novel Mechanisms of Toxic Bile Salt-Induced Hepatocellular Apoptosis

  • Lee, Byung-Hoon
    • Proceedings of the Korean Society of Toxicology Conference
    • /
    • 2002.11b
    • /
    • pp.107-114
    • /
    • 2002
  • Cholestatic liver injury results from the accumulation of toxic bile salts within the liver. The aim of the present study was to understand the mechanism of bile salts-induced hepatocellular apoptosis in bile duct-ligated (BDL) rats, using Western blot and immunohistochemical analysis.(omitted)

  • PDF

A Studies on the Bio-monitoring using Shell Valve Movements (SVMs) of Pacific Oyster Crassostrea gigas for Toxic Dinoflagellates, Genus Alexandrium (참굴, Crassostrea gigas의 패각운동을 이용한 유독와편모조 Alexandrium 속의 모니터링 연구)

  • Kim, Yoon Jeong;Yoon, Yang Ho
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.11
    • /
    • pp.778-784
    • /
    • 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.

Selection of Transition Point through Calculation of Cumulative Toxic Load -Focused on Incheon Area- (누적독성부하 산정을 통한 주민소산 전환시점 선정에 관한 연구 -인천지역을 중심으로-)

  • Lee, Eun Ji;Han, Man Hyeong;Chon, Young Woo;Lee, Ik Mo;Hwang, Yong Woo
    • Journal of the Korean Society of Safety
    • /
    • v.35 no.6
    • /
    • pp.15-24
    • /
    • 2020
  • With the development of the chemical industry, the chemical accident is increasing every year, thereby increasing the risk of accidents caused by chemicals. The Ministry of Environment provides the criteria for determining shelter-in-place or outdoor evacuation by material, duration of accident, and distance from the toxic substance leak. However, it is hard to say that the criteria for determining the transition point are not clear. Transition point mean the time that evacuation method is switched from shelter-in-place to outdoor evacuation. So, the purpose of this study was to calculate appropriate transition point by comparing the cumulative toxic load. Namdong-gu in Incheon Metropolitan City was finally selected as the target area, considering the current status of the population of Incheon Metropolitan City in 2016 and the statistical survey of chemicals in 2016. The target materials were HCl, HF, and NH3. Modeling was simulated by ALOHA and performed assuming that the entire amount would be leaked for 10 min. Residents' evacuation scenarios were assumed to be shelter-in-place, immediate outdoor evacuation, and outdoor evacuation at an appropriate time after shelter-in-place. Based on the above method, the appropriate transition point from residents located in A(800 m away), B(1,200 m away), C(1,400 m away) and D(2,200 m away) was identified. In HCl, appropriate transition point was after 15 min, after 16 min, after 17 min, after 20 min in order by A, B, C and D. In HF, appropriate transition point was before 1 min or after 16 min, before 4 min or after 19 min, before 5 min or after 20 min, before 14 min or after 26 min in order by A, B, C and D. In NH3, appropriate transition point at A was before 4 min or after 16. Others are not in chemical cloud. This study confirmed the transition point to minimize the cumulative toxic load can be obtained by quantitative method. Through this, it might be possible to select evacuation method quantitatively that cumulative toxic load are minimal. In addition, if the shelter-in-place is maintained without transition to outdoor evacuation, the cumulative toxic load will increase more than outdoor evacuation. Therefore, it was confirmed that actions to reduce the concentration of chemicals in the room were necessary, such as conducting ventilation after the chemical cloud passed through the site.