• 자원환경지질
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• 제45권2호
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• pp.205-215
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• 2012

금속이온은 토양이나 퇴적물 내의 광물에 수착되어 고착화될 수 있다. 여기서는 광물 표면의 화학적 특성과 금속이온의 수착에 관련된 이론 및 수착 연구를 위한 X-선 흡수 미세구조(extended X-ray absorption fine structure, EXAFS) 분석방법에 대해 알아보고 금속이온의 광물표면 수착에 관한 원자 단위 연구 결과를 정리하였다. 광물표면의 특성과 금속이온의 수착에 관한 원자 단위 이론의 이해는 원자 단위 분광법의 분석을 수행하는데 있어서 기초가 된다. 여기에 정리된 원자 단위 수착상 연구 결과는 외부권 착물, 내부권 착물, 표면침전뿐 아니라 공침전, 삼성분 착물, 수착반응 시간의 효과, 탈착가능성을 포함한다.

• 대한예방한의학회지
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• 제19권3호
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• pp.103-113
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• 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.

• Journal of Microbiology
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• 제39권2호
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• pp.83-88
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• 2001

There is considerable interest in how microbiological processes can affect the behaviour of metal contaminants in natural and engineered environments and their potential for bioremediation. The extent to which microorganisms can affect metal contaminants is dependent on the identity and chemical form of the metal and the physical and chemical nature of the contaminated site or substance. In general terms, microbial processes which solubilize metals increase their bioavailability and potential toxicity, whereas those that immobilize them reduce bioavailability. The balance between mobilization and immobilization varies depending on the metal, the organisms, their environment and physico-chemical conditions.

• 한국환경과학회지
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• 제7권4호
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• pp.565-572
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• 1998

This study estimate the degree of contamination in the streamwater around the Sudokwon landfill site. It was sampled at 10 sites in Jan., Apr., Jul. and Oct., 1996. There were analyzed five kinds of toxic chemical material-CN, AES, PCB, As, Org-p, and four kinds of heavy metal-Pb, Hg, Cd, $C^{+6}$ The result are 1)The COD was generally increased to compare before landfall, 2) The Org-P and PCB were not detected at all points, 3) The concentrations of Pb, $C^{+6}$ and As were lower than the environmental criteria values, 4) The CN, Hg and Cd were over envirommental criteria values. and so emergent regulation is needed, 5) The effects of the streamwater contamination were not only the leachate of the landfall, but also the small factories and agricultural land around the landfill.

• ALGAE
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• 제21권4호
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• pp.471-477
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• 2006

Amphora costata W. Smith 1853 is a down thrown diatom species and also known as metal corrosive ship-fouling organism. A. costata was isolated from Alang ship breaking yard, Alang and evaluated the toxicity tolerance and growth responses of the cultures exposed to different doses of toxic and relatively accessible heavy metals, such as Fe, Mn, Cd, Co, Cu, Zn, Ni, and Pb in the constantly monitored laboratory culture conditions. The strongest toxic effect was observed on A. costata exposed to Cd even at relatively low concentrations as compared to other metals. The following trend of decreasing order of toxicity i.e. Cd>Zn>Ni>Co>Pb>Cu>Fe was observed, when they were exposed to equal concentration and expose time.

• Advances in nano research
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• 제3권4호
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• pp.243-255
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• 2015

In this investigation, ecotoxicity of nano and micro metal oxides, namely silica ($SiO_2$) and alumina ($Al_2O_3$), on the growth of green algae (Porphyridium aerugineum Geitler) is discussed. Effects of nano and micro particles on the growth, chlorophyll content and protein content of algae are analysed using standard protocols. Results indicate that $SiO_2$ nano and micro $SiO_2$ particles are non-toxic to P. aerugineum Geitler up to a concentration of 1000 mg/L. In addition, $Al_2O_3$ microparticles are less toxic to P. aerugineum Geitler, whereas $Al_2O_3$ nanoparticles are found to be highly toxic at 1000 mg/L. Moreover, $Al_2O_3$ nanoparticles decrease the growth, chlorophyll content, and protein content of tested algae. In addition, zeta potential and contact angle are also important in enhancing the toxicity of metal oxide nanoparticles in aquatic environment. This study highlights a new insight into toxicity evaluation of nanoparticles on beneficial aquatic organisms such as algae.

• 한국환경농학회지
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• 제31권2호
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• pp.97-103
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• 2012

BACKGROUND: Metal mines were actively developed in the early twentieth century in Korea; however, most of these mines were closed and abandoned without proper management. Therefore, toxic metal contamination in the vicinity of Korean abandoned metal mines has been reported. A risk assessment for these metals was performed for residents near by abandoned Sanyang metal mine. METHODS AND RESULTS: Soil and groundwater samples were collected from May to October 2007 around the mine. After pretreatment of these samples, metal concentrations were measured and then a risk assessment was performed using the Korean soil-contamination risk assessment guidelines. Cancer risk was the highest from inhalation of Pb-contaminated soil, followed in descending order by As-contaminated soil inhalation and water ingestion. The sum of carcinogenic risks was $3.35{\times}10^{-3}$. The noncarcinogenic risk was observed for inhalation of Hg-contaminated soil (5.71). CONCLUSION: Inhalation of soil in dust was the principal pathway to cause the health risk and most of the risk was attributed to As, Pb,Cd, and Hg contamination.

• Membrane and Water Treatment
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• 제13권5호
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• pp.227-233
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• 2022

The objective of the study, to develop adsorbent based purifier for removal of radiological and nuclear contaminants from contaminated water. In this regard, 3-aminopropyl silica functionalized with ethylenediamine tetraacetic acid (APS-EDTA) adsorbent prepared and characterized by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Prepared APS-EDTA used for adsorptive studies of Cs(I), Co(II), Sr(II), Ni(II) and Cd(II) from contaminated water. The effect on adsorption of various parameters viz. contact time, initial concentration of metal ions and pH were also analyzed. The batch method has been employed using metal ions in solution from 1000-10000 ㎍/L, contact time 5-60 min., pH 4-10 and material quantities 50-200 mg at room temperature. The obtained adsorption data were used for drawing Freundlich and Langmuir isotherms model and both models were found suitable for explaining the metal ions adsorption on APS-EDTA. The adsorption data were followed pseudo second order reaction kinetics. The maximum adsorption capacity obtained 1.3037-1.4974 mg/g for above said metal ions. The results show that APS-EDTA have great potential to remove Cd(II), Co(II), Cs(I), Ni(II) and Sr(II) from aqueous solutions through chemisorption and physio-sorption.

• 환경생물
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• 제30권3호
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• pp.238-244
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• 2012

넙치, Paralichthys olivaceus 수정란의 부화율을 이용하여 중금속(Pb, Cr, As)의 독성 영향을 조사하였다. Pb, Cr, 및 As (0, 10, 100, 500, 1,000, 2,500, 5,000 ppb)에 수정란을 48 h 노출시킨 후, 정상 부화율을 백분율로 나타내었다. 중금속을 포함하지 않는 대조구에서는 정상 부화율이 80% 이상을 나타냈으나, 중금속 농도가 증가할수록 정상 부화율은 급격히 감소하였다. 정상 부화율은 Pb, Cr, 및 As에 대해 농도 의존적으로 감소하였으며, 각각 100, 100, 500 ppb 이상의 농도에서 유의한 차이를 나타내었다. P. olivaceus의 정상 부화율에 대한 Pb, Cr 및 As의 반수 영향농도($EC_{50}$)를 이용한 독성은 Cr>As>Pb 순으로 나타났다. Pb와 As의 NOEC와 LOEC 각각 100 ppb와 500 ppb로 유사한 값을 나타냈으며, Cr에 대한 NOEC는 10 ppb, LOEC는 100 ppb를 나타내었다. 이들 결과로부터 자연생태계 내에서 Pb과 As의 농도는 100 ppb, Cr 농도는 10 ppb를 초과할 경우 P. olivaceus 수정란의 정상 부화율은 독성 영향이 나타날 것으로 판단된다. 본 연구 결과를 바탕으로, P. olivaceus의 정상 부화율을 이용한 생물학적 평가방법은 중금속과 같은 유해물질에 대한 해양생태계의 영향을 판단하기 위한 시험방법으로 유용하게 이용될 수 있을 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.12-17
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• 2013

Heavy metal contamination of soil and water from industrial sources remains a worldwide environmental concern. Concentrations of toxic metals were measured in soil from banks of the Han and Anyang rivers. Pre-monsoon samples contained the highest heavy metal concentrations (Cu > As > Pb > Cd > $Cr^{6+}$; up to 57.80, 38.23, 25.43, 2.21, 0.32 mg/kg, respectively), but concentrations decreased at all sites during the monsoon and post-monsoon seasons. Higher heavy metal concentrations in pre-monsoon samples may be attributed to dust pollution, especially from roads near the river. A gradual reduction in heavy metal concentrations during the rainy season may be due to washing out. The high concentration of metals could cause health problems, especially in residential areas.