• Economic and Environmental Geology
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• v.41 no.1
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• pp.151-163
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• 2008

Since the country's opening to the world, China's rapid economic growth has resulted in strong demand for a wide variety of mineral commodities. During the same period, China's mineral production increased sharply. China's increased mineral production and demand affected the worldwide availability of minerals and metals, the market prices, and trade. Ministry of Land and Resources of China (MLR) planned to build as many as 10 strategic mineral reserve, including reserves of aluminium, copper, manganese, uranium, and other mineral that the country urgently needed. In white paper of China's mineral resources, China is planning the mineral resources conservation and its reasonable utilization, domestic supply increase of resources, activation of cooperative development with foreign partners, balance in resources development and environment conservation, and sustainable resources management as the mineral resources policies for the China's economic development.

• Korean Journal of Veterinary Service
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• v.29 no.4
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• pp.459-467
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• 2006

This study was designed to investigate if there were groundwater contamination in 17 landfill where slaughtered animals were buried during the crisis of 2002 foot-and-mouth-disease (FMD) outbreaks in Gyeonggi province. From March to August 2005 groundwater was collected once a month from 17 sites, and examined with potential for hydrogen (pH), colour, turbidity, lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), copper (Cu), zinc (Zn) , iron (Fe), manganese (Mn) , aluminium (Al), nitrate-nitrogen $(NO_3-N)$, ammonia-nitrogen $(NH_3-N)$, microbial pathogen and Escherichia spp. In the examination of $NH_3-N$ which of the mean concentration was from not-detected (ND) to 0.05 mg/l. The range of $NH_3-N$ level was $0.3-24.1mg/{\ell}$. However, groundwater from four sites was to go beyond the drinking water quality standard (DWQS), i.e., the mean concentration of those were $15.5mg/{\ell}\;(site\;1),\;20.7mg/{\ell}\;(site\;9),\;24.1mg/{\ell}\;(site\;13)\;and\;10.6mg/{\ell}\;(site\;17)$. In the investigation of pH, colour and turbidity, all of the pH were below of DWQS (pH 5.8-6.6), but one site in color test and four sites in turbidity test were over the standard level. Among 9 metal ions examined, Mn was in excess of DWQS, and its concentration was $2.4mg/{\ell}$. Pb, Cd, Hg and As were not traced. The contents of Cu, Zn, Fe and Al were $ND-0.22mg/{\ell},\;0.01-0.05mg/{\ell},\;ND-0.05mg/{\ell}\;and\;0.03-0.16mg/{\ell}$, respectively. Escherichiae spp were not identified, but bacterial colonies were detected at 3 groundwater including 2 sites over the DWQS at the level of $491CFU/m{\ell}\;(site\;4)\;and\;217CFU/m{\ell}\;(site\;15)$.

• Korean Journal of Soil Science and Fertilizer
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• v.2 no.1
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• pp.15-26
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• 1969

The study on physico-chemical characteristics of the acid sulfate soil present in Kimhae plain was carried out with 28 surface and subsoils from lower and higher produtive area and two representative profile samples from the areas reclaimed a few decades ago and around 10 years ago respectively. 1. There are no differences in soil texture between lower and higher productive soils being mostly silty clay loam and silty clay. 2. Very significant differences in pH, degree of base saturation and extractable aluminium content are observed; lower pH, lower degree of base saturation and higher aluminium in the lower productive soils and subsoils. The pH and degree of base saturation of these soils are extremely low whereas aluminium content is very high compared to ordinary paddy soil. 3. Cation exchange capacity of these soils are slightly higher than ordinary paddy soils. In higher productive soils, exchangeable calcium and magnesium are of same order, whereas in lower productive soils magnesium content is appreciably higher than calcium. 4. Though the soil is derived from marine and estuarine sediment, the soluble salt content is not high. There are only few lower productive surface soils and subsoils having Ec values of the saturation extracts higher than 4 mmhos but lower than 9 mmhos/cm. 5. Organic matter content of these soils is a bit higher compared to ordinary paddy soils, but, nitrogen content is comparatively low. C/N ratio of these soils is around 12. 6. Sulfur content is considerably higher but oxidizable sulfur is found to be very low. Total sulfur is generally high in subsoils and lower productive soils. 7. Active iron and available silica are slightly higher than ordinary paddy soils but easily reducible manganese is very low. Almost no differences are also observed between lower and higher productive soils. 8. Available phosphorus content is extremely low in particular, regardless of higher or lower productive soils. 9. The two representative profiles from the area of earlier reclamation and recent one show that samples from earlier reclaimed area contain less amount of free acids, sulfur compounds, toxic aluminium and soluble salts etc. than the other. This indicate greater leaching and possible addition of lime for a longer period of time. 10. From the results obtained, it can be concluded the higher productivity of group I soils is due to the greater leaching and neutralisation of acidity by liming materials, It can also be concluded that the productivity of both types can be increased by addition of liming materials and improvement of drainage facilities.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.812-817
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• 2003

This study was conducted to estimate the contents of heavy metals in tea products (n=200) and to provide a scientific basis for standardization of heavy metals in the Korea Food Code. The contents of mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), manganese (Mn), zinc (Zn), and aluminium (Al) were determined using a mercury analyzer, an AAS (atomic absorption spectrophotometer), and ICP (inductively coupled plasma spectrometer). The values of heavy metals in tea products were [minimum-maximum (mean), mg/kg] Hg: $N.D.{\sim}0.02$ (0.003), Pb: $N.D.{\sim}0.35$ (0.03), Cd: $N.D.{\sim}0.07$ (0.007), As: $N.D.{\sim}0.19$ (0.006), Cu: $N.D.{\sim}24.41$ (2.73), Mn: $N.D.{\sim}767.88$ (66.91), Zn: $N.D.{\sim}18.60$ (4.54), Al: $N.D.{\sim}1304.30$ (85.53). These results showed that metal contents in tea products in our markets were similar to those reported in other countries. The average weekly intakes of lead, cadmium, and mercury from tea products were $0.1{\sim}0.2%$ of PTWI (Provisional Tolerable Weekly Intake) that the JECFA (Joint FAO/WHO Expert Committee on Food Additives) has set to evaluate their safeties.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.349-355
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• 2012

In this study, we configured a system which ranks hazardous chemicals to determine their management priorities based on experts' opinions and the existing CRS (chemical ranking and scoring). Aggregate exposure of food, health functional food, oriental/herbal medicine and cosmetics have been taken into account to determine management priority. In this study, 25 hazardous chemicals were selected, such as cadmium, lead, mercury, and arsenic, etc. These 25 materials were ranked according to their 1) risk (exposure or hazard) indexes, 2) exposure source-based weight, and 3) public interests, which were also formed based on the existing priority ranking system. Cadmium was scored the highest (178.5) and bisphenol A the lowest (56.8). Ten materials -- cadmium, lead, mercury, arsenic, tar, acrylamide, benzopyrene, aluminium, benzene, and PAHs -- scored higher than 100. Eight materials -- aflatoxin, manganese, phthalate, chromium, nitrate/nitrite, ethylcarbamate, formaldehyde, and copper -- recorded scores in the range from 70 to 100. Also evaluated as potential risks were 7 materials; sulfur dioxide, ochratoxin, dioxins, PCBs, fumonisin, methyl mercury, and bisphenol A, and these materials were scored above 50. Then we compared risk index and correlation coefficient of total scores to confirm the validity of the total scores; we analyzed correlation coefficient of parameter and indicator. We discovered that the total score and weight, which has incorporated public interests, were high and statistically significant. In conclusion, the result of this study contributes to strengthening risk assessment and risk management of hazardous chemicals.