• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.65-71
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• 1994

This study was conducted to investigate the influence of treatment of fly ash on heavy metal contents in the arable soils. Rice was cultivated on the two types of paddy field(clay loam and sandy loam soil) with 0, 4, 8, 12t/10a of anthracite fly ash and bituminous coal fly ash, respectively. And soybean was cultivated on the same types of upland field with those of 0, 3, 6, 9t/10a, respectively. At the harvest time, the heavy metal contents in surface and subsoil were investigated. The results were summarized as follows : 1. Anthracite fly ash. 1) In the paddy field of clay loam, the contents of Cu and Zn in the surface soil and Cd and Ni in the subsoil were increased with the increase of the amount of fly ash applied, but the others didn't show that tendency. 2) In the paddy field of sandy loam, only the content of Fe was increased in the surface and subsoils. 3) In the case of upland soil, the concentration of Ni and Cr in the surface soil and Cd in the subsoil were increased in the clay loam soil, and those of Cr in the surface soil and Pb in the subsoil were increased in the sandy loam soil. 2. Bituminous coal fly ash 1) In the paddy field of clay loam, the contents of Cu and Zn in the subsoil were increased with increase of the amount of fly ash applied, but in the case of sandy loam, those of Pb and Ni in the surface soil were increased. 2) In the upland soil of clay loam, the concentration of Ni in the surface soil and Pb in the subsoil were increased. 3) In case of upland soil of sandy loam, the contents of Cr and Fe were increased in the surface and subsoil, respectively, but those of Cu and Mn were increased in the both of the surface and subsoil.

• Economic and Environmental Geology
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• v.39 no.3 s.178
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• pp.213-227
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• 2006

The geochemical evolution of mine drainage and leachate from waste rock dumps and stream water in Pb-As-rich abandoned Sechang mine area was investigated to elucidate mechanisms of trace metals. Total and sequential extractions were applied to estimate the distribution of trace metals in constituent phases of the waste rocks and to assess the mobility of trace metals according to physicochemical conditions. These discharged waters varied largely in chemical composition both spatially and temporally, and included cases with significant]y low pH (in the range 2.1-3.3), and extremely sulphate (up to 661 mg/l and metal contents (e.g. up to 169 mg/l for Zn, 27 mg/l for As, 3.97 mg/l for Pb, 2.99 mg/l for Cu, and 1.88 mg/l for Cd). Arsenic and heavy metal concentrations at the down-stream of Sechang mine have been decreased nearly to the background level in downstream sites (sites 8 and 16) without any artificial treatments. The oxidation of Fe-sulfides and the subsequent hydrolysis, of Fe(II), with precipitation of poorly crystallized minerals, constituted an efficient mechanism of natural attenuation which reduces considerably the transference of trace metals (i.e. Fe and As) to rivers. The dilution of drainage by mixing with pristine waters provoked an additional decrease of trace metal concentrations and a progressive pH increase. On the other hand, the most soluble cations (i.e. Zn) remained significantly as dissolved solutes until the pH was raised to approximately neutral values. With respect to ecotoxicity, it is likely that the Zn pollution is of particular concern in Sechang mine area. This was confirmed by the sequential extraction experiment, where Zn in wet waste-rock samples occurred predominantly in the exchangeable fraction (65-89% of total), while Pb was the highest in the reducible and carbonate fractions, and Cd, Cu and As in the residual fraction. Pb concentration in the readily available exchangeable fraction (34-48% of total) was dominated for dried waste rock samples. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreased in the order of Zn>Pb>Cd>As=Cu.

• Korean Journal of Environmental Agriculture
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• v.39 no.1
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• pp.10-19
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• 2020

BACKGROUND: This study was to carry out risk assessment of contamination of cadmium (Cd), lead (Pb), and inorganic arsenic (I-As) in agricultural products of 25 crops from the abandoned mine areas. The 36 typical investigation sites located in Gyeongbuk provincial area were selected by considering the heavy metal levels, that had been known that the amount of the heavy metals exceeded the contamination level based on the previous survey. METHODS AND RESULTS: Cadmium, lead, and total arsenic (T-As) concentrations were determined using microwave device and ICP-MS. Inorganic arsenic was determined by HPLC-ICP-MS. The limits of quantification for heavy metals were 0.59 ㎍/kg for Cd, 0.42 ㎍/kg for Pb, 0.55 ㎍/kg for T-As, and sum of As (III) (1.74 ㎍/kg) and As (V) (2.25 ㎍/kg) for I-As, respectively. The contents of Cd, Pb, and I-As (only rice) were N.D.-0.958 mg/kg, N.D.-0.227 mg/kg, and 0.082 mg/kg, respectively, in the agricultural products. For risk assessment, dietary exposures of heavy metals through usual intake were 5.20×10^-4-7.15×10⁰ ㎍/day for Cd, 7.00×10^-5-7.75×10^-1 ㎍/day for Pb, and 1.17×10¹ ㎍/day for I-As, taking 0.01-14.37%, 0.01-2.05%, and 15.16% as risk indices, respectively. CONCLUSION: It requires to consider the critical levels of heavy metals in agricultural products due to unexpectedly high levels in a few places, while concentrations of heavy metals in the samples were relatively low in most areas.

• Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.2.1-2.9
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• 2019

In the present study, the protective effects of Hizikia fusiforme and Chlorella sp. extracts on lead acetate-induced hepatotoxicity were investigated. Hepatic damage was induced in rats by intraperitoneal (i.p.) injection of lead acetate and the protective effects of H. fusiforme (HZK) and Chlorella sp. (CHL) extracts on lead acetate-induced hepatic damage in rat liver were examined. The results revealed significantly increased glutamic oxaloacetate and glutamic pyruvic transaminase levels in the group treated with lead acetate only (Pb group); oral administration of HZK and CHL extracts tended to decrease the enzyme levels similar to those observed in the control group. Regarding antioxidant enzymes, superoxide dismutase activity was increased in the Pb group and decreased in a concentration-dependent manner in the HZK- and CHL-treated groups. Glutathione levels were increased in a concentration-dependent manner in the HZK- and CHL-treated groups. There was no significant difference in catalase activity. Western blot analysis showed inflammation-related protein expression in mitogen-activated protein kinase and Nrf2 pathways was affected in the HZK- and CHL-treated groups. Therefore, HZK and CHL extracts exerted antioxidant and anti-inflammatory effects against lead acetate-induced hepatotoxicity. Development of functional health foods containing HZK and CHL extracts, which have hepatoprotective effects against inhaled lead acetate, should be considered.

• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.22-33
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• 1992

In Iri industrial area, Heavy metals in ait of the factories, 10 metal and 8 non-metal factories, were examined for ten months(from Feb. to Nov, 1991). The methals in blood, urin and hair of 232 employees who have worked in the factories were also examined at the same time The results are summarized as follows 1. Heavy metals Pb, Cd and Mn in the metal factories were 0.031mg/m$^{3}$, 0.0065mg/m$^{3}$, and 0. 035mg/m$^{3}$ respectively, but 0.017mg/m$^{3}$, 0.021mg/m$^{3}$ and 0.014mg/m$^{3}$ in non-metal factories. 2. Heavy metals such as Pb, Cd and Mn in blood from employees in the metal factories were measured : 22.36$\mu$g/dl, 0.27$\mu$g/dl and 1.26$\mu$g/dl respectively, The values in the non-metal factories were 19.84$\mu$g/dl, 0.21$\mu$g/dl and 1.24$\mu$g/dl. 3. Heavy metals such as Pb, Cd and Mn in urine from employees in the metal factories were measured 32.94$\mu$g/l, 0.16$\mu$g/dl, and 1.60$\mu$g/dl respectively, whereas the values in the non-metal factories were 28.79$\mu$g/l, 0.13$\mu$g/dl and 1.35$\mu$g/l. 4. Heavy metals such as Pb, Cd and Mn in hair from employees in the metal factories were measured 8.92mg/kg, 0.33mg/kg and 3.71mg/kg respectively, but 8.14mg/kg, 0.31mg/kg and 3.26 rng/kg in the non-metal factories.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.96-96
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• 1993

간부분 절제술을 하지 않는 비수술적 방법으로서 D-galactosamine을 이용한 중기발암성 시험의 개발을 목적으로 F344 수괵 랫드를 이용하여 본 실험을 수행하였다. 실험 I 에서는 실험방법에 따라 3가지 모델로 구분하고, 각 모델에 처치군과 대조군을 두었다. 모델 1 에서는 실험개시시에 diethylinitrosamine (DEN)을 200 mg/kg body weight로 복강내로 1회 투여하고, 실험개시후 2및 5주에 D-galactosamine을 300 mg/kg body weight로 복강내로 각각 1회 투여하였다. 처치군에는 실험개시후 2주부터 6주간 2-acetylaminofluorene을 0.01%로 혼합한 사료를 급여하였으며, 대조군에는 기초사료를 계속 급여하였다. 모델 2에서는 모델 1의 4주차까지의 처치를 2회 반복하였다. 모델 3은 간부분 절제술을 하는 DEN-PH (diethylnitrosamine-partial hepatectomy) 모델과 같은 방법으로 처치하였다. 사육기간 중 매주 체중 및 사료소비량을 측정하였고, DEN 투여후 8주에 전동물을 부검하여 적출한 간의 중량을 측정하고, glutathione S-transferase placental form (GST-P) 양성 foci에 대한 면역조직화학적 염색표본을 만들어 GST-P 양성 foci의 수 및 면적을 측정하였다. 실험 II에서는 모델 1의 방법으로 phenobarbital(PB), 3-methylcholanthrene (3-MC), n-ethyl-n'-nitro-n-nitrosoguanidine 및 3,3'-diaminobenzidine외 GST-P 양성 foci의 발현정도를 조사하였다. 실험 I의 결과, 모델 1이 정상적인 체중 증가를 보여주었으며, 간조직의 GST-P 양성 foci 의 발현율이 가장 좋았다. GST-P 양성 foci의 면적은 큰것 부터 미상엽, 내측우엽, 외측우엽의 순으로 나타났으나 foci의 수는 모델별로 다르게 나타났다. 실험 II의 PB 투여군과 3-MC 투여군에서 GST-P 양성 foci의 수 및 면적의 유의성 있는 증가가 관찰되었다. 이와 같은 결과로 볼때, 비수술적 방법인 D-galactosamine 을 이용한 중기 발암성 검색법은 간부분 절제술을 이용한 중기발암성 검색법에 비하여 GST-P 양성foci의 발현능력이 동등하거나 더 우수하였으며, 간 및 간이외 장기의 발암물질에 대한 발암성 검색에 보다 유용할 것으로 생각된다.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.366-366
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• 2012

현재 사용되고 있는 투명전극재료 중에 ITO(Indium Tin Oxide)가 가장 투명하면서 전기도 잘 통하고 생산성도 좋다. 투명전극은 비저항이 $1{\times}10^{-3}{\Omega}/cm$이하, 면 저항이 $10^3{\Omega}/sq$이하로 전기전도성이 우수하고 380에서 780 nm의 가시광선 영역에서의 투과율이 80%이상이라는 두 가지 성질을 만족시키는 박막이다. 본 연구에서 X-ray Film을 제작하기 위하여 상용화된 ITO Glass 전극 기판에 X-ray가 조사되면 직접 전자 전공 쌍(electron-hole pair)을 발생시켜 전기적 신호를 발생하는 광도전체 물질(Photoconductor)인 PbO, $PbI_2$, $HgI_2$를 스크린 프린팅(Screen Printing)법을 이용하여 각각 제작하였다. 상부 전극으로 마그네틱 스퍼터링(Magnetic Sputtering) 진공 증착 장치를 사용하여 전류, 전압, 아르곤 및 산소 유입량등을 조절하면서 상부 전극을 증착하였다. 이때 타켓으로 $In_2O_3;SnO_2$ (조성비:90:10wt%)를 사용 하였고, base pressure는 $9{\times}10^{-7}torr$, deposition pressure는 $3{\times}10^5torr$를 고정하였다. 또한 전류와 전압은 각각 0.4A, 800V로 유지하고, $O_2$:0.3 ppm, Ar의 경우 4.9 ppm에서 70 ppm까지 올려 플라즈마를 활성화 시킨 후 90초 동안 ITO를 증착하였다. 본 실험에 제작된 박막으로 X-ray을 조사하여 검출기로써 특성 평가를 실시하였으며, 실험결과 X-선 투과와 전도성 등 두가지 특성이 동시에 만족 될 만한 성능을 가질 수 있음을 확인 할 수 있었다.

• Asian Journal of Atmospheric Environment
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• v.6 no.2
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• pp.118-126
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• 2012

To investigate the effect of aircraft traffic emissions on soil pollution, metal levels were analyzed for 8 metals (Fe, Cr, Pb, Zn, Cu, Ni, Mn and Cd) from the vicinity of the Indira Gandhi International (IGI) airport in Delhi, India. The texture of the airport soil was observed to be sandy. Among the metals, Cd showed minimum concentration ($2.07{\mu}g\;g^{-1}$), while Fe showed maximum concentration ($4379{\mu}g\;g^{-1}$). The highest metal accumulation was observed at the landing site. Significant correlations were observed between metals and different textures (sand, silt, and clay) as well as with organic carbon (OC). The results indicate that grain size play a major role in OC retention in soil and subsequently helps in adsorption of metals in soil. M$\ddot{u}$ller's geoaccumulation index (I-geo) showed that airport soil was contaminated due to Cd and Pb with the pollution class 2 and 1, respectively. Pollution load index of the airport site was 1.34-3 times higher than the background site. The results of factor analysis suggested that source of the soil metal is mainly from natural weathering of soil, aircraft exhaust, and automobile exhaust from near by area. With respect to Dutch target values, the airport soils showed ~3 times higher Cd concentration. The study highlighted the future risk of enhanced metal pollution with respect to Cd and Pb due to aircraft trafficking.

• Economic and Environmental Geology
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• v.42 no.2
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• pp.121-131
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• 2009

The distribution characteristics of heavy metals for surface sediments in east oceanic dumping area (EDA) and west oceanic dumping area (WDA) are evaluated by grain sizes, minerals, sedimentation rates and compositions of heavy metals. The mean grain sizes in EDA and WDA range from $7.95{\Phi}$ to $8.51{\Phi}$ and $7.42{\Phi}$ to $8.15{\Phi}$, respectively. These are mostly belonging to the M (mud) type. Minerals in the surface sediments consist of illite with chlorite, smectite, and kaolinite. Sedimentation rates estimated by $^{210}Pb$ method in EDA and WDA are 1.11 mm/yr$\sim$1.73 mm/yr and 1.87 mm/yr, respectively. According to the interrelationship, concentrations of Ni, Cu, Cr, and Zn are closely associated with mean grain size, Al, and Fe, whereas concentrations of Cd and Pb are poorly associated with ones. The enrichment factors of these elements are higher than 1.5, suggesting that the concentrations of Cd and Pb in the surface sediments are affected by anthropogenic sources. The $I_{geo}$-class numbers of Cd and Pb in the surface sediments are mostly classified in 2 to 4, showing moderate to strongly polluted. These numbers in EDA are higher than that of WDA, and the highest number is 4, indicative of the strongly polluted class. Our results show that the disposed wastes at EDA include mineralogical wastes, dredged materials from sewage disposals, and sludges from constructions having materials of WDA. The annual amount of oceanic dumping in EDA is double than that in WDA.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.204-215
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• 1993

Epoxy-activated chitin was synthesized by the reaction of epichlorohydrin with chitin which was isolated from waste marine sources such as crab shell. Followed by the reaction of epoxy-activated chitin with hexamethylenediamine, the aminohexyl chitin was synthesized. The aminohexyl chitin was subsequently reacted with epichlorohydrin to prepare the epoxy-activated aminohexyl chitin. Finally, the tannin-immobilized chitin (Resin I) was synthsized by the reaction of tannin solution with epoxy-activated aminohexyl chitin. Using silane coupling agent, the tannin-immobilized chitosan(Resin II) was synthesized by the reaction of $\gamma$-glycidoxypropyltrimethoxy silane with chitosan which was prepared by the deacetylation of chitin. Upon the pH variation, adsorptivities of these immobilized tannins to the metal ions such as $Cu^{+2}$, $Ni^{+2}$, $Cr^{+6}$, $Co^{+2}$, $Ca^{+2}$, $Pb^{+2}$, $Ba^{+2}$, and $UO_2{^{+2}}$ ions were determined by batch method. The adsorptivity tendencies of these immobilized tannin to the most of metallic ions were increased with pH. Furthermore, the adsorptivities of Resin(I) and Resin(II) upon the variation of pH, contact time, amount of resin and concentration of metal ion were investigated. As a result, it was found that these immobilized tannin on both chitin and chitosan showed good adsorptivities for uranyl ion.