• Economic and Environmental Geology
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• v.37 no.1
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• pp.73-86
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• 2004

In order to estimate the post-ingestion bioavailability of heavy metals and to assess the risk of adverse health effects on human exposure to toxic heavy metals, environmental geochemical surveys were undertaken around the Dogok Au-Ag-Cu and the Hwacheon Au-Ag-Pb-Zn mine sites. Human risk assessment of toxic heavy metals was performed with the results of the SBET(simple bioavailability extraction test) analysis for soil and chemical analytical data for crop plant and water. Arsenic and other heavy metals were highly elevated in tailings from the Dogok(218 As mg/kg, 90.2 Cd mg/kg, 3,053 Cu mg/kg, 9,473 Pb mg/kg, 14,500 Zn mg/kg) and the Hwacheon(72 As mg/kg, 12.4 Cd mg/kg. 578 Pb mg/kg, 1,304 Zn mg/kg) mines. These significant concentrations can impact on soils and waters around the tailing dumps. The quantities of As, Cd and Zn extracted from paddy soils in the Hwacheon mine using the SBET analysis were 55.4%, 20.8% and 26.4% bioavailability, respectively, and for farmland soils in the Dogok mine, 40.8%, 37.6% and 33.0% bioavailability, respectively. From the results of human risk assessment, HI(Hazard Index) value exceeded 1.0 for As in the Hwacheon mine and for Cd in the Dogok mine. Thus, toxic risks for As and Cd exist via exposure(ingestion) of contaminated soil, water and rice grain in these mine sites. The cancer risk for As by the consumption of rice and groundwater in the Hwacheon mine area was 8E-4 and 1E-4, respectively. This risk level exceeds the acceptable risk(1 in 100,000) for regulatory purpose. Therefore, regular ingestion of locally grown rice and ground-water by the local population can pose a potential health threat due to long-term arsenic exposure.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.87.1-87
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• 1999

• The Korean Journal of Ecology
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• v.22 no.3
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• pp.131-137
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• 1999

This study was carried out to investigate the activity of nitrogen fixation and accumulation of heavy metal and inorganic matter in Vicia amoena community at lower region in Kumho riverside, including Youngchon, Chimsangyo, Paldalgyo, Talseochon and Kumhogyo. The contents of inorganic matter and heavy metal of Kumho riverside soil increased in the down stream in each organ of the plant growing in the riverside. Generally, V. amoena community showed rapid growth of shoot and high value of Top/Root ratio. V. amoena community showed higher water content of shoot at late growth stage and higher chlorophyll content. The root nodule of V. amoena community appeared in April and increased by 0.30, 0.27, 0.24, 0.06 and 0.14 g/plant, and nitrogen fixation activity of nodule attained 20.1, 16.8, 15.4, 8.5 and 5.3 μmol·C₂H₄·g fw nodule/sup -1/·h/sup -1/ for non-contaminated area Youngchon, Chimsangyo, Paldalgyo, Talseochon and Kumhogyo, respectively, in June:. Nodule formation and nitrogen fixation activity were reduced in the down stream by the soil contamination and heavy metal accumulation and showed minimum values. at Talseochon and Paldalgyo. V. amoena showed growth adaptation against heavy metal toxicity by restricting heavy metal such as Pb, Cu, Zn, Fe from transport, and by accumulating high Ca ion in shoot, nitrogen and phosphorus in root at late growth stage than those at early one, respectively, but total heavy metal per plant showed higher values in shoot than those in root by high T/R ratio of plant growth.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.223-227
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• 2000

Absorption of Cadmium(Cd) and Arsenic(As) by lettuce following to the change of polyamine content in lettuce were examined to find the effect of these elements on lettuce growth and on the basic resistance mechanism. As the contents of Cd and As were increased in soil, the contents of these elements were significantly increased in lettuce but lettuce growth was decreased. Sequential fractionation experiment of the Cd and As treated soil was shown that exchangeable, dilute acid extractable, and organically bound form, which were more mobile and phyto-available, of Cd were increased by 5.6, 42.9, and 56.7% during a growing season whereas 17.6, 25.0, and 24.1% were increased in case of As, respectively. Specially, the Cd content of leaves and roots in lettuce was positively correlated with exchangeable, dilute acid extractable, and residual form of Cd in the treated soil. However, the As content of roots in lettuce was positively correlated with all chemical forms of As in the treated soil. The contents of putrescine and cadaverine, a kind of polyamine, were also increased in lettuce as both elements were increased in soil.

• Journal of Applied Biological Chemistry
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• v.63 no.2
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• pp.161-168
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• 2020

It is known that different plant species have ability to deposit different amounts of particulate matter (PM) on their leaves and plants can absorb heavy metals in PM through their leaves. Heavy metals in PM can have toxic effect on human body and plants. Therefore, PM on different roadside trees at Chungbuk national University including box tree (Buxus koreana), yew (Taxus cuspidate), royal azalea (Rhododendron yedoense), and retusa fringetree (Chionanthus retusa) was quantified based on particle size (PM_>10 and PM_2.5-10). The metal concentration in PM accumulated on leaves was analyzed using inductively coupled plasma-mass spectroscopy. In this study, the mass of PM_>10 deposited on the surface of the tree leaves ranged from 6.11 to 32.7 ㎍/㎠, while the mass of PM_2.5-10 ranged from 0 to 14.8 ㎍/㎠. The royal azaleas with grooves and hair on the leaf surface retained PM particles for longer time, while the yews and box trees with wax on leaf surfaces accumulated more PM. The PM contained elements in crustal material such as Al, Ca, Mg, and Fe and heavy metals including Cu, Pb and Zn. The concentration of elements in crustal material was higher in the coarser size, while heavy metal concentration was relatively higher in the finer size fraction. The Mn, Cd, Cu, Ni, Pb, and Zn concentrations of leaves and PM_2.5-10 were significantly correlated indicating that PM was taken up through tree leaves.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.352.1-352.1
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• 2016

양자점은 나노미터 크기의 반도체 결정으로 밴드갭에 따라 광학적, 전기적 성질이 달라지는 독특한 성질을 가지는 형광물질으로 활발히 연구되고 있다. 중금속을 기반으로 한 양자점은 높은 발광효율과 광안전성을 가지며, 가시광선 영역에서 빛을 내는 특징을 가지고 있다. 그러나 중금속을 사용하기 때문에 독성이 있어 인체나 환경에 유해하여 응용 연구에 제한적이다. 반면에, 탄소 기반의 양자점은 중금속 기반의 양자점과 비슷한 성질을 가질 뿐만 아니라, 높은 용해도와 낮은 독성으로 인해 생체적합성이 높다는 장점이 있다. 이를 이용하여 발광다이오드(LEDs), 태양전지, 광촉매 뿐만 아니라 바이오이미징, 바이오센서 등 생물학분야에도 응용 될 수 있다. 본 연구에서는 Bottom-up 합성 방법으로 유기전구체를 이용하여 질소를 함유하고 있는 양친매성 탄소 양자점(N-GQDs)을 합성하였다. 합성에 사용한 유기전구체는 기존에 보고된 유기전구체와 다르게 반응 진행 중에도 pH 측정 결과 중성을 나타내며, 반응 온도($225^{\circ}C$)와 유사한 온도에서도 pH 값은 여전히 6.0 이상의 값을 나타냈다. 중성을 띄는 특징으로 인해 추가적인 산제거 과정이나 표면안정화 과정이 필요 없다는 장점을 가지고 있다. 합성된 N-GQDs는 높은 결정성의 원형구조를 가지며, 원자힘현미경(AFM) 분석을 통해 높이가 ~ 1.5 nm 미만으로 3층 이하의 두께로 형성되었음을 확인하였다. 또한, 적외선 분광법(FT-IR) 분석을 통해 O-H기, 방향족 고리의 C = C (또는 C = N)기 및 C-N기가 각각 ~3250, ~1670과 ~1140 cm-1에서 확인할 수 있다. 합성된 양자점을 유기태양전지의 active layer에 소량(2 wt%) 첨가하여 양자점의 광학적, 전기적 성질을 확인하였다. 비교군 유기태양전지보다 N-GQDs가 첨가된 유기태양전지의 외부양자효율(PCE)이 7.3%에서 8.4%로 약 20%가 증가하는 것을 보였다. 이는 양자점이 상대적으로 흡수가 약한 단파장 영역의 빛을 흡수하고 PL을 내어 active layer로 에너지 트랜스퍼 현상이 일어나 전자전달을 원활하게 해 주기 때문이다. 앞으로 본 연구의 가능성과 추가적인 연구를 통해 더 많은 분야에 응용되기를 기대한다.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.740-744
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• 1994

This study was undertaken to prove the suppressing effect of green tea on the intestinal absorption of heavy metals using in vitro membrane filtration system. From drinking water contaminated with 10 and 100 times level of water quality standard for heavy metals, the removal ratio of lead (Pb) was $50{\sim}70%$ by green and black teas, and $30{\sim}40%$ by roasted barley tea. The removal ratio of cadmium (Cd) was $30{\sim}40%$ by green tea and black teas, and $10{\sim}20%$ by roasted barley tea. The removal effect from drinking water contaminated with both lead and cadmium was lower than that from water contaminated singly with lead or cadmium. It appears that tea components and filter membrane compete toward the adsorption of two heavy metals. Among the extraction conditions of raw tea materials at $70^{\circ}C$, 2 minutes and $95^{\circ}C$ , 10 minutes, the removal ratios of heavy metals were similar.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.409-413
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• 2015

To enhance phytoremediation, which removes heavy metal from soil, transgenic plants were applied to contaminated soil. We constructed a transformation vector expressing both $TgMTP_1$ (T. goesingense metal tolerance protein):HA and TgMTP:GFP genes. Transgenic plants were generated using an Agrobacterium-mediated transformation system that expressed the two vectors. Screening and analysis confirmed the incorporation of foreign genes into the Arabidopsis thaliana genome. Callus was induced in the 116 T3 line. These transgenic plants and calli were used for further analyses on the accumulation of Ni. The 116 T3-line plants and calli from selected lines were resistant to heavy metals and accumulated Ni in their leaves. The expression level of TgMTP RNA was equal in all leaves, but protein stability increased in the leaves with Ni treatment. According to these results, we suggest that $TgMTP_1$-overexpressing plants may be useful for phytoremediation of soil.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.220-226
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• 1997

To study the possibility of agricultural utilization of the municipal sewage and the industrial wastewater sludges, the chemical properties of soil, the growth response of corn plant and uptake of inorganic nutrients in plant tissues were investigated by application of the composts made of the sludges to the pots at the rate of 2,000kg/10a. The contents of organic matter, T-N, $P_2O_5$ and K in soil were increased by application of the composts. Each heavy metals contents in soil were increased very slightly by application of the composts. The fresh weights of corn plant were increased with $9{\sim}19%\;and\;60{\sim}79%$ at the plot of compost and NPK+composts in comparing with the plot of NPK, respectively. Uptake of N, $P_2O_5,\;K_2O$, CaO and MgO in stem and leaf of corn plant were increased by applications of the composts.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.44-53
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• 2021

Urban stormwater runoff contains heavy metals that accumulate in on-site treatment systems, thus resulting to facility deterioration and maintenance problems. In order to resolve these problems, low impact development (LID) technologies that promote natural materials circulation are widely used. LID facilities are capable of treating heavy metals in the runoff by means of plant uptake; however, the uptake or phytoremediation capabilities of plants have not been studied extensively, making it difficult to select the most suitable plant species for a certain LID design. This study investigated the vegetative components of an LID facility, roadside plants, and plants in landscape areas with different heavy metal exposure and frequency to determine the uptake capabilities of different plant species. The plants harvested inside the LID facilities and roadsides with high vehicular traffic exhibited greater heavy metal concentrations in their tissues as compared with the plants in landscape areas. Generally, the accumulation of heavy metals in the plant tissues were found to be influenced by the environmental characteristics (i.e. influent water quality, air pollution level, etc.). Dianthus, Metasequoia, Rhododendron lateritium, and Mugwort were found to be effective in removing Zn in the urban stormwater runoff. Additionally, Dianthus, Metasequoia, Mugwort, and Ginkgo Biloba exhibited excellent removal of Cu. Cherry Tree, Metasequoia, and mugwort efficiently removed Pb, whereas Dianthus was also found to be effective in treating As, Cr, and Cd in stormwater. Overall, different plant species showed varying heavy metal uptake capabilities. The results of this study can be used as an effective tool in selecting suitable plant species for removing heavy metals in the runoff from different land use types.