• Title/Summary/Keyword: W/Cu joint

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Safety Assessment of Heavy Metals in Agricultural Products of Korea (우리 나라에서 생산된 농산물의 중금속 안전성 평가)

  • Kim, Min-Kyeong;Kim, Won-Il;Jung, Goo-Bok;Yun, Sun-Gang
    • Korean Journal of Environmental Agriculture
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    • v.20 no.3
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    • pp.169-174
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    • 2001
  • This study was conducted to compare and evaluate the heavy metal contents of agricultural products in Korea and to compare with relevant international criteria such as the Average Daily Intake(ADI) and the Provisional Tolerable Weekly Intake(PTWI) proposed by the joint FAO/WHO Codex Committee on additives and contaminant. Contents of heavy metal in cereals, pulses, potatoes, vegetables and fruits were in the range of $0.010{\sim}0.073$ for Cd, $0.40{\sim}6.45$ for Cu, $0.083{\sim}0.698$ for Pb, $2.45{\sim}16.30$ for Zn, $0.171{\sim}1.378$ for Ni, $0.023{\sim}0.233$ for Cr and $0.026{\sim}0.070$ mg/kg(F.W.) for As. Heavy metal contents of cereals, pulses, potatoes, vegetables and fruits were with natural content levels proposed by FAO/WHO and were similar to value monitored in other countries. Also, average intake of heavy metal from agricultural products was lower than the ADI and PTWI by the joint FAO/WHO Codex Committee on Additives and Contaminants. Therefore, none of the cereals, pulses, potatoes, vegetables and fruits evaluated showed accumulation of such heavy metal high enough to cause health problems to human.

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Geochemical Exploration Technics in the Pungchon Limestone Area (풍촌 석회암지대 탐사에 적용될 새 지화학탐사법 연구)

  • Moon, Kun Joo
    • Economic and Environmental Geology
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    • v.23 no.4
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    • pp.369-381
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    • 1990
  • Most of significant ore deposits in South Korea such as the Sangdong W - Mo, the Yeonhwa Pb-Zn and the Geodo Cu-Fe skarn ore deposits occur at the southern limb of the Hambaeg syncline in the Taebaeg Basin. The mineralization took place in the interbedded limestone of the Myobong Formation and the Pungchon limestone of the Great Limestone Group of the Cambrian age, generally striking E-W and dipping 25-30 degrees north. There are no outcrops of the skarn-type orebody at the northern limb of the syncline. In order to find a clue of a possible hidden orebody localized at the limestones in the northern limb, a lithogeochemical exploration by using carbon isotope and some elements such as Si, Ca, Fe and Al at the Sangdong Mine area has been attempted as for a modelling study. For this study, 45 samples from the Pungchon limestone which do not show any megascopic indication of mineralization have been taken in both the mineralized zone and the unminerallized zone at the Sangdong Mine area. Analytical data show that there are big differences in the contents of CaO and $Al_2O_3$ between the Pungchon limestone of the mineralized zone and that of the unmineralized zone. Carbon isotope data exhibit that ${\delta}^{13}C$ values of the Pungchon limestone in the mineralized zone are highter than those in the unmineralized zone. The difference in the analytical values of CaO, $Al_2O_3$ and the carbon isotope between the mineralized and the unmineralized zones is as follows ; Unminerallized zone Mineralized zone CaO 51.3% 43.5% $Al_2O_3$ 0.6% 2.4% ${\delta}^{13}C$ -0.39 permil -0.56 permil $Fe_2O_3$ 0.9% 1.4% $SiO_2$ 3.0% 2.4% The decrease in the Si content of the Pungchon limestone in the mineralized zone is contrary to the result of the previous study (Moon, 1987). On the basis of identification of the increase in the Al content of the limestone in the mineralized zone, it could be deduced that the decrease in the Si content of the Pungchon limestone might be due to the result of increase in the alteration products mainly occurred along fracture-system such as joint cracks or minor faults and that the phenomena shown by the Si and Al content in the mineralized zone might be derived from the thermal effect of granite extended mineralizing activity to the overlied limestone on the surface. Higher mean values of Fe and Al as well as lower mean values of carbon content and the ${\delta}^{13}C$ than mean values of those in the Pungchon limestone at the northern limb of the Hambaeg Syncline may be applicable in exploration for blind orebodies.

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