• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.29-35
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• 2009

In this study, the effect of pH and temperature on the adsorption behavior of acid mine drainage (AMD) on coal mine drainage sludge (CMDS) has been investigated during the treatment of coal mine drainage (CMD) by electrical purification method. The pH$_{zero\;point\;charge}$ (pH$_{zpc}$) of CMDS was 5. The removal ratio of copper, zinc, cadmium, iron were increased according to the increase of pH value. The adsorption amount of copper showed 0.64 mg g$^{-1}$ sludge. It was independent of pH value. The adsorption amount of the other metals showed l.l times when pH was 3. The adsorption amount of chromium was a little bit increased at the pH value higher than 7 due to a small amount of the chromium was eluted as $Cr(OH)_6^{3-}$. The amount of metals' absorption were decreased according to temperature was increase at pH value was 3. The selectivity order was Cd>Fe > Zn > Cu. The amount of absorption showed q$_{max}$ Cu 2.747 mg g$^{-1}$ andZn 2.525 mg g$^{-1}$ when pH value higher than 5. It was independent of temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.3
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• pp.274-279
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• 1985

Proximate compositions, minerals and protein fractions of the roots of cultured and wild Codonopsis lanceolata of different age groups were examined as the basic research for the study of their source of processed foods. The most abundant proximate composition of the roots of C. lanceolata was observed to be total sugars and next come crude protein, crude fiber, crude fat and ash in descending order irrespective of cultured and wild ones. The richest mineral contained in the roots was noticed to be K and followed by Mg and Ca. Generally increased tendency of crude protein, fat, ash, K, Mg, Ca, Mn, Zn, Cu and P contents were observed with older roots, however, decreased total sugars and Fe content. Lead and cadmium content was far bellow the authorized tolerance limits. The quantitative fractionation of the protein of the roots ranked albumin the highest content, followed by globuin, prolamin and glutelin. Decreased albumin content was observed with the older age roots, while increased globulin, prolamin and glutelin content. The minimum solubility of the soluble protein of the roots was found to be at pH 4.0 and maximum, at pH 10.0. Disc gel electrophoresis of the soluble protein of C. lanceolata roots showed almost similar patterns and numbers of bands. The molecular weight for main band protein was estimated to be about 90,000.

• Journal of Environmental Health Sciences
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• v.36 no.6
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• pp.456-464
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• 2010

Recently, heavy metals contamination of the agricultural soil and crops surrounding mining areas has been identified as one of the most serious environmental problems in South Korea. The Ministry of the Environment in Korea conducted a Preliminary National Environmental Health Survey (PNEHS) in abandoned metal mines in 2007. The priority for a subsequent detailed examination was ranked from the results of PNEHS. The studied mine which was ranked as being of the highest priority is located in the midwestern part of Korea and was operated from 1911 to 1985. In this study, the contamination levels of the heavy metals in the abandoned metal mine were investigated. From the results, the average daily dose (ADD), target hazard quotient (THQ) and target cancer risk of the heavy metals were evaluated. The concentration of arsenic (As) in all of the tailings from the mine was higher than its countermeasure standard of Korea. In particular, the highest concentration of As, 330 mg/kg, was up to 15 times higher than its countermeasure standard. The average concentration of As in agricultural soils was higher than the warning standard of Korea, and higher than its countermeasure standard at six sites. The average concentrations of the analyzed heavy metals in agricultural soil were below the warning standard, but concentrations of cadmium (Cd) and lead (Pb) at 4 sites were higher than its warning standard. The average concentration of As in surface water exceeded the warning standard of Korea. The value of the THQ of As for the tailings was higher than the health protection standard 1. The value of THQ of As for the farmlands was lower than the standard, while the hazard index (HI) of As was higher than the standard. The value of target cancer risk (TCR) of As, $6.44{\times}10^{-4}$, were higher than the health protection standard of a lifetime risk for TCR at $1{\times}10^{-6}$. This suggests that the residents around the metal mines are exposed to As pollution with a carcinogenic risk.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.246-253
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• 1998

Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri which possessed the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The binding sites of heavy metal in the cells were investigated by chemical modification of functional groups the cell walls. To determine the binding sites of heavy metal in the cells, electrochemical charge of amine and carboxyl groups in the cell walls of heavy metal-tolerant microorganisms were chemically modified. Chemical modifications of amine groups did not affect the heavy metal uptake as compared to native cell walls. In contrast, modifications of carboxyl groups drastically decreased heavy metal uptake as compared to native cell walls, and electron microscopy confirmed that the form and structure of the heavy metal uptake were different from those of native cell walls. The results suggested that the carboxyl groups were the major sites of heavy metal uptake in the heavy metal-tolerant microorganism cell.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.73-81
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• 1997

Retention ponds have been dug along some of the motorways to control water flow during rainstorms and to minmize environmental pollution. A retention pond located at Les Ardilleres about 20km South of Orleans along the A-71 motorway has been selected to evaluate the effectiveness of such a pond as a trap for heavy metals. Based on the "index of geoaccumulation" and the "enrichment factor" normalized to Fe introduced by Muller in 1979 and by Helz in 1976, respectively, the degree of contamination by heavy metals for the roadside soil and the settling particles was evaluated. As expected, the contamination was very severe in the roadside soil, while it was not so great in the settling particles. Using these methods, cadmium anomaly was traced in the settling particles of the retention pond, their occurrence being attributed partly to natural and partly to anthropogenic pollution. The estimated input of heavy metals associated with settling particles to the pond was 0.9 g/day Pb, 2.1 g/day Zn and 6mg/day Cd. A tentative mass balance of Pb and Zn originated by motor vehicles suggested that only 5 to l1% of heavy metals deposited on the surface of the motorway is carried to the retention pond by runoff water ; suggestions are made to improve their efficiency.ve their efficiency.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.407-410
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• 2002

Monochromatic x-ray CT has several advantages over conventional CT, which utilizes bremsstrahlung white x-rays from an x-ray tube. There are several methods to produce such monochromatic x-rays. The most popular one is crystal diffraction monochromatization, which has been commonly used because of the fact that the energy spread is very narrow and the energy can be changed continuously. The alternative method is the use of fluorescent x-ray, which has several advantages such as large beam size and fast energy change. We have developed a parallel-beam and a fan-beam monochromatic x-ray CT, and compared some characteristics such as accuracy of CT numbers between those systems. The fan beam monochromatic x-rays were generated by irradiating target materials by incident white x-rays from a bending magnet beam line NE5 in 6.5 GeV Accumulation Ring at Tukuba. The parallel beam monochromatic x-rays were generated by using a silicon double crystal monochromator at the bending magnet beam line BL-20BM in Spring-8. A Cadmium telluride (CdTe) 256 channel array detector with 512mm sensitive width capable of operating at room temperature was used in the photon counting mode. A cylindrical phantom containing eight concentrations of gadolinium was used for the fan beam monochromatic x-ray CT system, while a phantom containing acetone, ethanol, acrylic and water was used for the parallel monochromatic x-ray CT system. The linear attenuation coefficients obtained from CT numbers of those monochromatic x-ray CT images were compared with theoretical values. They showed a good agreement within 3%. It was found that the quantitative measurement can be possible by using the fan beam monochromatic x-ray CT system as well as a parallel beam monochromatic X-ray CT system.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.162-169
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• 2020

This study was conducted to survey levels of heavy metals, benzopyrene and mycotoxins in teas purchased from online markets, supermarkets, and traditional markets in Gwangju, Korea. We examined the arsenic, cadmium and lead content in heavy metals. We also tested for benzo(a)pyrene, which is classified as a carcinogen. In addition, we tested for the mycotoxins aflatoxin (AFB₁, AFB₂, AFG₁, AFG₂), ochratoxin A (OTA), fumonisin (FUB₁, FUB₂), and zearalenone (ZON). According to our results, heavy metals were detected within the allowable range (below 5.0 mg/kg for lead) and all samples met with the standards for tea as presented in the Korean Food Code. The Benzo(a)pyrene showed a detection rate of 12.8% in 16 of 125 samples and mycotoxins showed 23.2% in 29 of 125 samples. However, safe levels regarding benzo(a)pyrene and mycotoxin in tea were not ascertainable since the standards are not set in the Korean Food Code.

• Analytical Science and Technology
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• v.23 no.3
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• pp.284-294
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• 2010

In this study, river water-based reference materials (RMs), NIER-I08RW and NIER-I09, for trace metal analysis were prepared and certified for Pb, Cd, Cr and Cu with evaluation of uncertainties. The RMs were confirmed to be homogeneous enough to be used as proficiency testing materials since within-bottle homogenieties of the RMs were lower than 0.3 times of targeted standard deviation of proficiency testing. The RMs were distributed to environmental testing laboratories for the proficiency testing and the variation of Z scores of the proficiency testing results were compared for different assigned values. The relative bias, $B_{relative}$, deviations between reference values and consensus values, were lower than ${\pm}$1 except for cadmium of NIERI08RW. The results showed both values were in a good agreement and only 2.9% of Z scores changed by using a different assigned values such as consensus and reference values.

• Journal of Soil and Groundwater Environment
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• v.10 no.2
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• pp.44-51
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• 2005

Fractional composition and mobility of some heavy metals in sediments from Okdong stream are investigated. The fractional scheme for heavy metals in the sediment was established for five chemically defined heavy metal forms as adsorbed fraction, carbonate fraction, reducible fraction, organic fraction, and residual fraction. The most abundant fraction heavy metals in the sediments is reducible and secondly abundant is organic fraction. Adsorbed fraction is minor part of the total heavy metals. Mobilization of heavy metals in the sediments from Okdong stream occur $19.8{\sim}56.7%$ of total cadmium concentrate. The most abundant fraction of the sediment metal is organic fraction in Cu, Pb metals investigated. Labile fraction of sediment metals are $0.5{\sim}48.5%$ of total Zn, $2.6{\sim}48.1%$ of total Pb, and $0.2{\sim}36.9%$ of total Cu, respectively. Most of labile fraction consists of reducible fraction for Cd, Zn, adsorbed fraction for Pb, reducible fraction for Cu, adsorbed fraction for Ni. The Mobilization of Zn and Cu is most likely to occur when oxygen depletes and that of Pb and Ni occurs when physical impact, oxygen depletion and pH reduction.

• Journal of Mushroom
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• v.17 no.4
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• pp.191-196
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• 2019

The edible ectomycorrhizal mushroom Amanita javanica is a valuable species protected by forest law in Korea. However, basic characterization data on its use as an important forest resource has been limited. This study was performed to determine mycelia growth characteristics of the domestically isolated Amanita javanica strain NIFoS 1267 on potato dextrose agar media under diverse culture conditions. Physical factors temperature, pH, and light, as well as chemical factors salts, heavy metals, and pesticides were examined for their effects on the growth of the mushroom strain. The mycelia of A. javanica strain exhibited optimal growth when cultured in dark at 30℃ in media with a pH of 5-6. Normal levels of growth were observed in media containing up to 2% saline. At a heavy metal ion content of 50 ppm, mycelial growth was not affected by arsenic ion but was affected by cadmium and lead ions. In the tests performed with two pesticides used in Korean forests, the growth of the mushroom strain was not affected by the presence of abamectin, but was inhibited in media containing acetamiprid, emamectin benzoate, or thiacloprid. These results are expected to facilitate artificial cultivation of A. javanica as a new commercial product.