• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.51-62
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• 2009

This study was carried out development a new composting system to lower copper and zinc concentration in plg sludge compost and conduct an inquiry into the possibility of crop cultivation. The concentrations of nitrogen, phosphorus and pH averaged 4.4%, 6.3% and 7.57, respectively, which were higher concentrations than in commercial organic fertilizers, and the concentrations of copper and zinc averaged 805 and 1,704 mg/kg, respectively, which were beyond the heavy metal concentration limit in byproduct compost. Hydrated citric acid I lowered the concentrations of copper and zinc by 58% and 97%, respectively and hydrated oxalic acid II lowered the concentrations of copper and zinc by 48% and 56%, respectively in pig sludge compost. Lower concentrations of copper and zinc in pig sludge resulted from the enhanced hydrated-citric acid concentration in organic acid solution mixed with distilled water. The concentrations of copper and zinc were 330, and 41 mg/kg in the pig sludge treated with 100% hydrated citric acid. Agitation composting system stabilized the compost earlier than the stationary composting system, in which the stabilization condition was confirmed by higher temperature by $4^{\circ}C$ at highest temperature and 7 days earlier cooling down after highest temperature. The levels of germination index (G.I) 80 were obtained 15 and 20 days after composting in agitation and stationary composting system, respectively. The concentrations of copper and zinc were 2.4 and 4.26 mg/kg respectively in soils amended with pig sludge compost after removing process of heavy metals by citric acid, but 8.0 and 22.37 mg/kg, respectively in soils amended with Pig Sludge. The concentrations of heavy metals was highest in com cultivated in soils amended with pig sludge. The copper and zinc concentrations In corn leaves were 75.2 and 50.56 mg/kg respectively, which were 4 and 2 fold higher than the com cultivated in soils amended with pig sludge compost after heavy metal removing process by hydrated citric acid.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.135-138
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• 2004

본 연구는 중금속으로 오염된 폐수처리에 있어 친환경적 유기흡착제로서 휴믹물질의 활용성을 평가하기 위한 기초 연구로서 이탄(peat moss)으로부터 Humin을 분리 한 후, 중금속 이온(Cd(II),Cu(II))과의 흡착특성을 조사하였다. 이탄으로부터 추출한 peat-Humin의 함량은 94%이상을 나타냈으며, 분자의 작용기 특성은 일반 토양 휴믹물질(soil humic substance)과 유사하였다. peat-Humin과 중금속 이온(Cd(II),Cu(II))과의 흡착 반응은 5분내에 빠른 흡착형을 보였으며, pH 5-6에서 가장 높은 중금속 제거율을 보였다. pH 3의 산성조건에서도 50%정도의 제거율을 보였다. pH 5에서의 등온흡착 실험결과를 Freundlich 등온식에 적용하여 해석한 결과, 각의 중금속에 대한 peat-Humin의 흡착상수(Kf)는 Cd(II)이 8.07 그리고 Cu(II)가 4.56으로 나타났다.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.111-116
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• 1999

Distribution of heavy metal (Zn, Pb, Cu, Cd) concentrations within forest soils was investigated in Mts. Surak and Bulam around the outskirt area, and Mts. Bukak and Inwang around the downtown area of Seoul. Metal concentrations in these soils were higher in the A horizons than in the B horizons. The mean concentrations of Zn, Pb, Cu, and Cd in the A horizons were 4.39 mg/kg, 9.09 mg/kg, 1.67 mg/kg, and 0.03 mg/kg, respectively. The concentrations in the B horizons were 2.18 mg/kg in Zn, 5.74 mg/kg in Pb, 0.55 mg/kg in Cu, and 0.01 mg/kg in Cd, respectively. With positive correlation among the metal concentrations, Zn, Pb, and Cu concentrations in the A horizon were positively correlated with soil organic matter contents (r=0.39~0.83, p<0.01), while Pb and Cu concentrations were negatively correlated with soil pH (r=-0.53~0.59, p<0.01). The results suggest that the metals in forest soils have accumulated more in the downtown than in the outskirt areas.

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.187-192
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• 1997

We carried out a survey on tributary streams in some agricultural areas along Nakdong River to evaluate the effects of agricultural practices on pollution of stream water and groundwater. General properties, nutrient materials and heavy metals in water samples were measured. General physicochemical properties of tributary stream waters were at levels favorable for agricultural water. Heavy metals, except Zn, were mostly not detected. Total-N contents were much higher than the criteria of agricultural water, and nitrate-N accounts for more than a half of total-N. Phosphorus contents were higher than the lower level of P for algae growth and the contents were high especially in summer. In ground waters which are used for irrigation, P were mostly at same levels as those in streams, and nitrate contents were higher than 10mg/L in some samples. In these results only those N and P contents in stream and ground waters higher than pollution criteria are problematic and they are traceable to agricultural nonpoint sources-fertilizers, livestock farms and sewage. Further researches are needed to evaluate contributions of each nonpoint source on stream water pollutions.

• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.25-40
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• 2001

In order to investigate the degree of heavy metal pollution, 280 urban gully-pot sediments were collected from 13 localities in eastern part of Seoul. The uncontaminated stream sediments were also studied for comparison. A series of studies have carried out concerning the physicochemical characteristics of the sediments and the distribution of Cd, Co, Cr, Cu, Ni, Pb, and Zn. Total metal concentrations of gully-pot sediments and uncontaminated stream sediments were analyzed using acid extraction. After predigestion with $NHO_3$, the sample was digested with mixed acid ($NHO_3$-$HClO_4$). The gully-pot sediments were characterized by very high concentrations of Zn, Cu, Pb and Cr, indicating an anthropogenic contribution of these metals to the sediment chemistry Heavy metal concentrations in the gully-pot sediments were 1-329 times higher than the mean content of metals in the uncontaminated stream sediments, depending on the metals. In particular, the highest mean concentrations of Zn, Cu, Pb and Cr were noticed in the gully-pot sediments from Yeouido, Junggu, Junggu, and Dongdaemungu, respectively. The mean value of total Zn concentration in the business and commercial areas is 2-3.5 times higher than that in industrial areas. This suggests that Zn is mainly derived from automobiles (rubber of automobile tires). The mean concentrations of Cu and Cr are significantly high in the commercial and industrial areas, indicating that industrial activities may cause the accumulation of Cu and Cr in the sediments. The Pb level in gully-pot sediments is comparatively low, due to the use of unleaded gasoline in automobiles since 1987.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.745-749
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• 1994

Animal experiments were conducted to confirm the suppressive effect of green tea on the intestinal absorption and tissue accumulation of toxic heavy metals in rats. When drinking water contaminated with 500 and 5000 times level of water quality standard for lead or cadmium was administrated to rats for 3 weeks, feed intake and body weight gain were not significantly differrent among all groups except for high cadmium group. In the relative weights of target organs, kidney and femur showed a significant difference by heavy metal administration and green tea did not influence on the weights. Green tea showed a suppressing effect on the accumulation of heavy metals in target organs, in which the reducing effect in femur was $25{\sim}45%$ for lead, and 42% for cadmium. As calcium content of femur decreased by heavy metal administration was increased in green tea group, it was concluded that heavy metal accumulation in femur was interrupted by tea beverage.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.31-42
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• 1999

To investigate the effects of the composts made of sewage sludges on the physico-chemical properties of soil and growth of paddy rice, the variations of chemical properties in soil, the contents of inorganic matters and heavy metals in plant tissues, the contents of heavy metals in brown rice, the growth response of paddy rice and grain yield were investigated. The results were summarized as follows : The contents of organic matters, N, available $P_2O_5$ and exchangeable K in soil were increased by application of the composts. The contents of N and available $P_2O_5$ in soil were remarkably decreased at the harvesting time in comparing with the 20th day after application of the composts. The contents of heavy metals in soil were increased very slightly by application of the com-post. At the harvesting time, the contents of N and K were not varied in all plant tissues at the plot of the compost in comparing with the plot of the NPK. The content of $P_2O_5$ in plant was increased by application of the composts. The contents of heavy metals in plant tissues and brown rice were not changed among the treatments. When the composts were applied to the pot at the rates of 1,000, 2,000, 4,000 and 6,000kg/10a with NPK, the numbers of grain yield were increased with 3, 18, 44 and 54% in comparing with NPK plot, respectively. Dry weight, the numbers of tillers and spikelet of the rice plant were increased by application of the composts.

• Economic and Environmental Geology
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• v.35 no.6
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• pp.553-565
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• 2002

Seasonal variations in vertical distributions of metals were investigated in the contaminated paddy soils around Siheung Cu-Pb-Zn and Deokeum Au-Ag mines. Geochemical behavior of metals was also evaluated with respect to redox changes during the cultivation of rice. Two microcosms simulating the rice-growing paddy field were set up in the laboratory. The raw paddy soils from two sites showed differences in mineralogy, metal concentrations and gecochemical parameters, and it is suggested that high proportions of exchangeable fractions in metals may give high dissolution rates at Deokeum. In both microcosms of Siheung and Deokeum, redox differences between surface and subsurface of paddy soils were maintained during the flooded period of 18 weeks. Siheung soil had neutral to alkaline pH conditions, while strongly acidic conditions and high Eh values were found at the surface soil of Deokeum. The concentrations of dissolved Fe and Mn were higher in the subsurface pore waters than in interface and upper waters from both microcosms, indicating reductive dissolution under reducing conditions. On the contrary, dissolved Pb and Zn had high concentrations at the surface under oxidizing conditions. From the Siheung microcosm, release of dissolved metals into upper waters was decreased. presumably by the trap effect of Fe- and Mn-rich layers at the interface. However, in the Deokeum microcosm, significant amounts of Pb and Zn were released into upper water despite the relatively lower contents in raw paddy soil, and seasonal variations in the chemical fractionation of metals were observed between flooded and drained conditions. Under acidic conditions, rice may uptake high amounts of metals from the surface of paddy soils during the flooded periods, and increases of exchangeable phases may also increase the bioavailability of heavy metals in the drained conditions.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.371-379
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• 2018

In many countries, recycling coal ashes as backfill materials for subsided lands, abandoned mine tunnels, and road pipeline constructions by making low-strength concretes with minimal amounts of cement is frequently considered for massive treatment of coal ashes. This study investigates the variation of heavy metals in the concrete test pieces prepared for the cases of using only Portland cement as binding material, fly ash as a replacement of the cement, sand as aggregates, and disposed ashes in the ash ponds as a replacement of aggregates. Heavy metal contents were measured based on the aqua regia extraction technique following the Korean Standard for Fair Testing of Soil Contamination and the influences of each materials on the total heavy metal contents were also assessed. Results show that the cement has the highest Cu, Pb, and Zn concentrations than any other materials. Therefore, the test pieces show significant concentration decreases for those metals when the cement was replaced by fly ash. Ponded ash shows low concentrations relative to fly ash in most of the parameters but shows higher Cu and Ni, and lower Pb levels than the sand aggregate. In overall, heavy metal levels of the test pieces are regulated by mixing among the used materials. Test pieces prepared during this study always show concentrations much lower than the Worrisome Level of Soil Contamination (Area 1), which was designated by the Soil Environment Conservation Act of Korea.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.55-61
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• 2016

BACKGROUND: This study was carried out to survey the levels of heavy metals in perennial root vegetables and to assess dietary exposure and risk to the Korean population health.METHODS AND RESULTS: Perennial root vegetables (n=214) including Panax ginseng C.A mayer, Woodcultivated ginseng, Codonopsis lanceolata, and Platycodon granditloum were collected from markets or harvested from farmhouse in Korea. Lead(Pb), cadmium(Cd) and arsenic (As) analysis were performed with microwave device and inductively coupled plasma mass spectrometer. Limit of detection for heavy metals were 0.010~0.050 μg/kg, while limit of quantitation were 0.035~0.175 μg/kg. The recovery results were in the range of 76~102%. The average contents of heavy metals in perennial root vegetables were in the range of Pb 0.013(Panax ginseng C.A Mayer)~0.070 (Wood-cultivated ginseng) mg/kg, Cd 0.009(Panax ginseng C.A Mayer)~0.034(Codonopsis lanceolata) mg/kg, and As 0.002(Panax ginseng C.A Mayer)~0.004(Plafycodon grandiflorum) mg/kg, respectively. For risk assessment, daily intakes of heave metals were estimated and risk indices were calculated in comparison with reference dose. The dietary exposures of heavy metals through usual intake were Pb 0.070 μg/day, Cd 0.041 μg/day and As 0.008 μg/day, taking 0.03%, 0.08% and 0.0003% as risk indices, respectively.CONCLUSION: The risk level for Korean population exposed to heavy metals through intake of perennial root vegetables was far low, indicating of little possibility of concern.