• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.541-555
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• 2016

This study determined the concentrations of lead and cadmium in 18 species of commonly consumed fish and assessed the risk based on provisional tolerable weekly (monthly) intakes [PTW(M)I] % as affected by behavioral characteristics, such as migration and settlement. In the 18 species, the mean concentrations of lead and cadmium were higher in the 11 species of migratory fish (llargehead hairtail Trichiurus lepturus, chub mackerel Scomber japonicus, Pacific saury Cololabis saira, skipjack tuna Katsuwonus pelamis, Pacific cod Gadus macrocephalus, anchovy Engraulis japonicus, Alaska pollack Theragra chalcogramm, brown croaker Miichthys miiuy, Japanese Spanish mackerel Scomberomorus niphonius, yellow croaker Larimichthys polyactis, and Pacific herring Clupea pallasii) than in the seven demersal species (red stingray Dasyatis akajei, brown sole Pleuronectes herzensteini, bastard halibut Paralichthys olivaceus, conger eel Conger myriaster, blackmouth angler Lophiomus setigerus, rockfish Sebastes schlegelii, and filefish Stephanolepis cirrhifer). Based on the mean concentrations, the PTWI % of lead and cadmium in commonly consumed migratory fish were 1.900 and 2.986%, respectively, which were higher than the values for lead and cadmium in the commonly consumed demersal fishes (0.257 and 0.318%, respectively). The estimation of weekly (monthly) intakes and target hazard quotients for the toxic elements lead and cadmium revealed that the commonly consumed migratory and demersal fish do not pose any health risks for consumers.

• Resources Recycling
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• v.9 no.6
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• pp.45-52
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• 2000

Generally, the residues of EAF's dusts treated by reduction process at high temperature are disposed. If the residues can be recycled as iron sources of EAF by upgrading their iron contents, it can be expected to reduce the amounts of disposed wastes and the environmental impacts. Reduction of EAF's dusts mixed with millscale was carried out in rotary hearth furnace to upgrade iron contents of reduction residues. Dusts should be reduced rapidly to protect from reoxidation of reduced iron residue which can be reoxidized at high temperature. In our experimental conditions, optimum reduction time was about 40min. and iron contents of the residues were increased with increasing mixing ratio of millscale and upgrade to 85% at 50%wt mixing ratio. Zinc and lead contents in residues were about 3% and 0.5% respectively. The residues reduced rapidly must be recycled in EAF because heavy metal elements in the residues can be extracted easily and contaminate air and water.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.510-522
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• 1999

The air pollutants ; $SO_2$, $SO{_4}^{-2}$, $NO{_3}^-$, $Cl^-$ are absorbed into soils through falling with dusts and rain from the atmosphere. The sources of heavy metal contaminants in the environments are agricultural and horticultural materials, sewage sludges, fossil fuel combustion, metallurgical industries, electronics and waste disposal etc.. The soils and hydrosphere can be polluted on the way of the circulation of these heavy metals. Studied pollutant anions are $SO{_4}^{-2}$, $NO{_3}^-$ and $Cl^-$ and heavy metals are Se, Mo, Zn, Cd, Pb, Mn, Cr, Co, V, As, Cu and Ni which are the elements to be concerned with the essentials for plants, with animal and human health. This study is with the aim of selecting the species of roadside trees and green space trees which have excellent absorption of air pollutants and heavy metals from the atmosphere and the soils in the urban area. Two areas are designated to carry out this study : urban area ; Kwangju city and rural area ; the yard of Forest Environment Institute of Chollanam-do, at Sanje-ri, Sampo-myum, Naju city, Chollanam-do (23km away from Kwangju). This study is carried out to understand the movement of anions and heavy metals from the soils to the trees in both areas, the absorption of anions and heavy metals from atmosphere into leaves and the amounts of anions and heavy metals in leaves and fine roots(< 1mm dia.) of roadside trees and green space trees in Kwangju and trees in the yard of Forest Environment Institute of Chollanam-do. The tree species selected for this study in both areas are Ginkgo biloba, Quercus acutissima, Cedrus deodara, Platanus occidentalis, Robinia pseudoacacia, Alnus japonica. Metasequoia glyptostroboides. Zekova serrata. Prunus serrulata var. spontanea, and Pinus densiflora. The results of the study are as follows : 1. $SO{_4}^{-2}$, $NO{_3}^-$ and $Cl^-$ concentrations are higher in the soils of the urban area than in those of the rural area, and $NO{_3}^-$ and $SO{_4}^{-2}$ are higher in the leaves than in the roots due to the absorption of the these pollutants through the stomata. 2. Ginkgo biloba, Robinia pseudoacacia. Zekova serrata, Quercus acutissima, and Platanus occidentalis can be adequated to the roadside trees and the environmental trees due to their good absorption of $NO{_3}^-$ and $SO{_4}^{-2}$. 3. Heavy metals in the soils of both areas are in the order of Mn > Zn > V > Cr > Pb > Ni > Cu > Mo> Cd, and in the leaves and roots of the trees in the both areas are in the order of Mn>Zn>Cr>Cu>V>Ni. Both orders are similar ones except V. There are more in the urban soils than in the rural soils in amount of Mn, Zn, Pb, V, Cu. 4. It is supposed that there is no antagonism between Mn and Zn in this study. 5. Se, Co and As are not detected in the soils, the leaves and the roots in both areas. Sn, Mo, Cd and Pb are also not detected in the leaves and roots in spite of considerable amount in the soils of both areas.

• Analytical Science and Technology
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• v.9 no.4
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• pp.336-344
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• 1996

The extraction of trace cobalt, copper, nickel, cadmium, lead and zinc in urine samples of organic and alkali metal matrix into chloroform by the complex with a dithizone was studied for graphite furnace AAS determination. Various experimental conditions such as the pretreatment of urine, the pH of sample solution, and dithizone concentration in a solvent were optimized for the effective extraction, and some essential conditions were also studied for the back-extraction and digestion as well. All organic materials in 100 mL urine were destructed by the digestion with conc. $HNO_3$ 30 mL and 30% $H_2O_2$ 50 mL. Here, $H_2O_2$ was added dropwise with each 5.0 mL, serially. Analytes were extracted into 15.0 mL chloroform of 0.1% dithizone from the digested urine at pH 8.0 by shaking for 90 minutes. The pH was adjusted with a commercial buffer solution. Among analytes, cadmium, lead and zinc were back-extracted to 10.00 mL of 0.2 M $HNO_3$ from the solvent for the determination, and after the organic solvent was evaporated, others were dissolved with $HNO_3-H_2O_2$ and diluted to 10.00 mL with a deionized water. Synthetic digested urines were used to obtain optimum conditions and to plot calibration-eurves. Average recoveries of 77 to 109% for each element were obtained in sample solutions in which given amounts of analytes were added, and detection limits were Cd 0.09, Pb 0.59, Zn 0.18, Co 0.24, Cu 1.3 and Ni 1.7 ng/mL, respectively. It was concluded that this method could be applied for the determination of heavy elements in urine samples without any interferences of organic materials and major alkaline elements.

• Journal of Soil and Groundwater Environment
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• v.20 no.7
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• pp.61-69
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• 2015

This study was performed to provide fundamental data to establish the new soil pollution standards and the soil contamination management plans in a rational manner. The distribution characteristics of new soil contaminants such as barium (Ba) and chromium (Cr) in soils (n=140) were investigated in relation to land-use classification and geological features. Also, the sequential extraction test was conducted to evaluate fate and mobility of new soil contaminants. The soil samples taken from 140 sites were analyzed to survey distribution levels of selected new soil contaminants. The average concentration and range for hazardous metals (Ba, Cr) were Ba 128.946 (26.757~489.587) mg/kg, Cr 30.121 (2.579~132.783) mg/kg. Based on land use classification, the highest Ba concentration was found in factory soils, followed by dry field and park soils, while Cr concentration was highest in rice paddy soils, followed by dry field and factory soils. Within 10 geological units investigated the highest Ba and Cr concentrations were observed in the soils from Okcheon group and metamorphic rocks, respectively. The BCR (European Community Bureau of Reference) sequential extraction was conducted to identify chemical distributional existence of 2 elements of soils from each geological unit. Ba in soils is mainly assumed to exists as reducible form (such as BaSO₄, BaCO₃) and Cr in soils mainly is assumed to exist as residual form (such as Cr₂O₃, Cr_xFe_1-x(OH)₃(x < 1)).

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.44-50
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• 2000

This study was carried out to get the basic data on the efficient processing method of food wastes for utilizing as the resources of swine feeds composition, mineral and toxic elements of food waste were estimated in relation to the steps of processing and fermentation with MS (Miraculous soil-bacteria) microorganism complex. The chemical composition of food wastes was largely varied according to disposing sites, collection time and season. Offensive odor was reduced by anaerobic fermentation with MS microorganism complex. Food wastes fermented with MS microorganism complex have high contents in crude protein (24.1% D.M) and crude fat (12.9% D.M). Mineral composition was to be relatively well balanced compared to other plant or animal feed resources. Particularly the content of sodium was slightly higher than that of grains or agricultural byproducts. In food wastes fermented with MS microorganism complex, heavy metals such as Hg, As or F were not detected. Pb or Cd were detected in small quantities but their levels were below the dose s-permitted feeding standard of permitted dose in feeding standard. These results indicated that food wastes could be efficiently used for the resources of swine feeds through proper processing and fermentation.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.261-267
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• 2011

ACKGROUND: Cadmium (Cd) has long been recognized as one of most toxic elements. Application of organic amendments and phosphate fertilizers can decrease the bioavailability of heavy metals in contaminated soil. METHODS AND RESULTS: This study was conducted to evaluate effect of combined application of phosphate fertilizer and manure in reducing cadmium phytoavailability in heavy metal contaminated soil. Phosphate fertilizers [Fused and super phosphate (FSP) and $K_2HPO_4$ (DPP)] and manure (M) were applied as single application (FSP, DPP, and M) to combined application (FSP+M and DPP+M) before radish seeding. $K_2HPO_4$ decreased $NH_4OAc$ extractable Cd and plant Cd concentration, mainly due to increases in soil pH and negative charge. However, FSP increased $NH_4OAc$ extractable Cd and plant Cd concentration. Manure significantly increased soil pH and negative charge. Combined application of phosphate fertilizer and manure were much more effective in reducing Cd phytoavailability than a simple application of each component. Calculated solubility diagram indicated that Cd concentrations in the solution of soils amended with phosphate fertilizers and manure were undersaturated with respect to all potential Cd minerals [$Cd_3(PO_4)_2$, $CdCO_3$, $Cd(OH)_2$, and $CdHPO_4$]. Plant Cd concentration and $NH_4OAc$ extractable Cd were negatively related to soil pH and negative charge. CONCLUSION: Alleviation of Cd phytoavailability with phosphate fertilizer and manure can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than Cd and phosphate precipitation. Therefore, combined application of alkaline phosphate materials and manure is effective for reducing Cd phytoavailability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1270-1276
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• 2013

Laver, a red algae belonging to the genus Porphyra tenera, is one of the most widely consumed edible seaweeds in Korea, China, and Japan. Lavers are usually consumed in dried, roasted, and seasoned forms to improve their palatability. We evaluated the composition of amino acids, minerals, and trace heavy metals in these three differently cooked forms of laver. The moisture and ash contents of three differently cooked lavers ranged from 1.49~9.69% and 6.07~10.31%, respectively. The crude protein and lipid content ranged from 17.24~36.88% and 0.52~42.42%, respectively. Dried laver was found to be a good source of amino acids such as taurine, alanine, and glutamic acid (871.10 mg, 833.53 mg, and 719.77 mg per 100 g dry weight, respectively). Laver was a good source of macro and micro minerals such as K, Ca, Mg, Na, P, I, and Fe, although laver more extensively cooked (roasted and seasoned) contained less minerals compared to the dried form. Mercury levels in the three differently cooked forms of laver were all less than 100 ng/g dry weight (the limit of detection with our methodology). The levels of arsenic were the most abundant elements in the differently cooked laver. There was a clear variation, depending on the cooking process, in terms of amino acid, mineral, and trace metal contents of laver.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.3940-3955
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• 2023

A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: ⁶⁰Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are Ф57 and Ф55; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable.

• Environmental and Resource Economics Review
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• v.14 no.2
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• pp.257-290
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• 2005

Korean energy use in industrial sector has increased more rapidly than other sectors during 1980~2000 periods. Relatively higher increases in industrial sector energy consumption raise questions whether government policy of rationalization of industrial energy use has been effective. In this study, we use 80-85-90 and 90-95-00 constant price input-output table to analyze increases in industrial energy use. Using an adjusted version of structural decomposition model introduced by Chen and Rose (1990), we decompose Changes of energy use into 17 elements. We classify entire industry sector into 32 sectors including four energy sectors (coal and coal products, refined petroleum, electricity and town gas). We then analyze changes of energy use by industrial level to check differences among industrial energy demand structures. Finally, we compare three industries, electronic product manufacturing, metal manufacturing and construction, that represent technology and capital intensive, energy and material intensive and labor and capital intensive industry. As results, we find that high energy using industries make the most effort to reduce energy use. Primary metal, petrochemical and mon-metal industries show improvements in elements such as energy and material productivity, energy and material imports, energy substitution and material substitutions towards energy saving. These results imply that although those industries are heavy users of energy, they put the best effort to reduce energy use relative to other industries. We find various patterns of change in industrial energy use at industrial level. To reduce energy use, electronic product manufacturing industry needs more effort to improve technological change element while construction industry needs more effort to improve material input structure element.