• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.25-34
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• 1995

A Study on environmental Investigation in Imha Dam for the finding the degree of water quality and heavy metals was carried out at 4 sampling station during the period from August 15, 1993 to May 7, 1994. The results were as follows. 1. The ranges of values of pH for water were st. 1-7.56, st.2-7.77, st.3-7.9, st.4-7,7 on the average. Total average of pH values were 7.56-7.9 2. The ranges of values of DO for water were st.1-8.71($mg/{\ell}$), st.2-8.64($mg/{\ell}$), st.3-10. 25($mg/{\ell}$), st.4-9.01($mg/{\ell}$) on the average. Total average of DO of values were 8.64-10.25($mg/{\ell}$). 3. The ranges of values of BOD for water were st.1-1.1($mg/{\ell}$), st.2-1.0($mg/{\ell}$), st.3-0 86($mg/{\ell}$), st.4-0.99($mg/{\ell}$) on the average. Total average of BOD of values were 0.86-1.1($mg/{\ell}$). 4. The ranges of values of COD for water were st.1-1.12($mg/{\ell}$), st.2-1.4($mg/{\ell}$), st.3-0 98($mg/{\ell}$), st.4-1.46($mg/{\ell}$) on the average. Total average of COD of values were 0.98-1.46($mg/{\ell}$). 5, The ranges of values of T- N for water were st.1-0.36($mg/{\ell}$), st.2-0.49($mg/{\ell}$), st.3-0 23($mg/{\ell}$), st.4-0.83($mg/{\ell}$) on the average. Total average of T-N of values were 0.23-0.83($mg/{\ell}$). 6. The ranges of values of T-P for water were st.1-0.053($mg/{\ell}$), st.2-0.06($mg/{\ell}$), st.3-0.02($mg/{\ell}$), st.4-0.07($mg/{\ell}$) on the average. Total average of T-P of values were 0.02-0.07($mg/{\ell}$). 7. In the E. soli group distribution were counted st.1-1130, st.2-1113, st.3-152.3, st.4-1253 by the MPN test. Total distribution of E. soil group were 152.3-1253. 8. The concentration of heavy metals of Cu, Mn, Pb, Zn were measured st.1-0.59, 0.18, 0 04, 74.6( ${\mu}g/{\ell}$), st.2-0.39,0.29,0.03, 54.3(${\mu}g/{\ell}$), st.3-0.1,0.3, ND, 8(${\mu}g/{\ell}$), st.4-0.96, 0 26,0.23,45.6(${\mu}g/{\ell}$) on the average. Cd, Hg, Cr were not detected in the sampling site.

• 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.

• Journal of Preventive Medicine and Public Health
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• v.23 no.1 s.29
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• pp.1-10
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• 1990

The protective effect of sodium selenite($Na_2SeO_3$) against the cytogenetic toxicity of heavy metals was investigated on human whole-blood cultures in relation to induction of sister chromatid exchange (SCE) in secondary metaphase chromosome. Methylmercury chloride($CH_3HgCl$), cadmium chloride($CdCl_2$), potassium dichromate($K_2Cr_2O_7$), and sodium selenite caused to the typically dose-dependent increase in sister chromatid exchanges (SCEs) by the concentrations ranging from $0.3{\mu}M\;to\;10{mu}M$. However, the inductions of sister chromatid exchanges by methylmercury chloride or cadmium chloride were inhibited by the simultaneous addition of sodium selenite $1.2{mu}M$. The frequencies of SCE were decreased to the level of control in the molar ratios as 2:1, 1:1, 1:2, and 1:4 of selenium selenite vs. methylmercury chloride, and as 1:1 and 1:2 of selenium selenite vs. cadmium chloride, while the frequencies of SCE induced by potassium dichromate were not changed by the addition of sodium selenite in culture condition. Mitotic indices were decreased in the higher concentrations of chemicals and not significantly changed by the simultaneous addition of sodium selenite to the culture condition containing each chemicals.

• Toxicological Research
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• v.26 no.3
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• pp.209-216
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• 2010

Limb bud (LB) and central nerve system (CNS) cells were prepared from 12.5 day old pregnant female Crj:CD (SD) rats and treated with olaquindox and vitamin A. Cytotoxicity and inhibition on differentiation were measured in each cell. Three doses of olaquindox (4, 21 and 100 mgkg), and 0.2 and 75 mg/kg of vitamin A were administered to pregnant rat for 11 days from $6^{th}$ to $16^{th}$ of pregnancy. $IC_{50}$ values of olaquindox for proliferation and differentiation in CNS cell were 22.74 and $28.32\;{\mu}g/ml$ and 79.34 and $23.29\;{\mu}g/ml$ in LB cell and those values of vitamin A were 8.13 and $5.94\;{\mu}g/ml$ in CNS cell and 0.81 and $0.05\;{\mu}g/ml$ in LB cell, respectively. Mean body weights of pregnant rats were decreased at high dose of olaquindox (110 mg/kg) but relative ovary weight, number of corpus lutea, and number of implantation were not changed. Resorption and dead fetus were increased at high dose of olaquindox, and relative ovary weight, the number of corpus lutea and implantation, and sex ratio of male to female were not significantly changed in all dose of olaquindox. Mean fetal and placenta weights were significantly (p < 0.01) decreased in rats of high group. Seven fetuses out of 103 showed external anomaly like bent tail, and 10 out of 114 fetuses showed visceral anomalies at high group. The ossification of sternebrae and metacarpals were significantly (p < 0.01) increased by low and middle dose of olaquindox but it was significantly (p < 0.01) prohibited by high dose of olaquindox. In rats treated with vitamin A, the resorption and dead fetus were increased by high dose. Mean fetal weights were significantly (p < 0.01) increased by low dose but significantly (p < 0.01) decreased by high dose. Thirty four fetuses out of 52 showed external anomaly; bent tail (1), cranioarchschisis (14), exencephaly (14), dome shaped head (22), anophthalmia (15), brcahynathia (10) and others (19). Forty five fetuses out of 52 showed soft tissue anomaly; cleft palate (42/52) and anophthalmia (22/52) by high dose of vitamin A. Sixty one fetuses out of 61 (85.2%) showed skull anomaly; defect of frontal, partial and occipital bone (21/61), defect of palatine bone (52/61) and others (50/61). In summary, we support that vitamin A is strong teratogen based on our micromass and in vivo data, and olaquindox has a weak teratogenic potential in LB cell but not in CNS cell. We provide the in vivo evidence that a high dose of olaquindox could have weak embryotoxic potential in rats.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.451-463
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• 2009

The purpose of this research is to develop thin film materials and fabrication process for efficient $TiO_2$/CdTe solar cells. In this work photocatalyst titanium dioxide was prepared by sol-gel procedure according to reaction condition, the mole ratio of $H_2O$/TTIP, pH of solution and aging condition of powder. The prepared titanium dioxide was thermally treated from 300 to $750^{\circ}C$. Maximum intensity of anatase phase of titanium dioxide was achieved by calcination at $600^{\circ}C$ for 2 hr. And it was mixture of anatase and rutile phase when temperature of calcination was $750^{\circ}C$. It has been known that the properties of synthesized titanium dioxide according to aging time and calcination temperature was converted to anatase phase crystal on increasing of aging time. Also the current density has been increased with aging time and temperature, the efficiency has been increased with because of reason on above results. The formation of chemical bonding on oxygen and cadmium telluride under oxygen circumstances had been observed, and oxygen of thin film surface on cadmium telluride had been decreased with the treatment of chromate and hydrazine. As results had been shown that the energy conversion efficiency of cadmium telluride use by rapidly treatmented heat at the condition of $550^{\circ}C$ under air circumstance got 12.0%, 6.0% values according to $0.07cm^2$, $1.0cm^2$ surface area, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.275-281
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• 1996

The objective of the study was to investigate the effects of water treatment sludge (WTS) on the growth of soybean and carrot, and uptake of some inorganic components in the plants. WTS was incorporated to field at the rates of 0, 1, 3, and 5 tons per 10a on the basis of dry weight. With the application of the sludge, OM and CEC in the soil increased slightly while the concentration of available phosphorous decreased. And heavy metals, including Pb, Cd, Cr, As and Hg, were not detected at the harvest stage in crops. With an increase in the application of the sludge, the concentration of phosphorous in the seed of soybean and the root of carrot tended to be decreased. There seems no correlation between rate of application of the sludge and uptake of Al in the plants. The yield of soybean was the highest when applied to one ton sludge and the yield on carrot increased with an increase in rate of applied sludge. Also, the concentration of carotene increased with an increased application of the sludge. But, application of WTS showed to deteriorate the visual quality with an irregularity of carrot's surface. This results indicate that application of WTS will be give a positive and negative effects on soil and crops.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.201-206
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• 2012

Horse manure general composition and contaminants, heavy metals content analysis was investigated as follows. The moisture content of horse feces was 76.1% and 96% for horse urine. The average T-N, T-P, T-K concentrations of the racing horse were 0.18%, 0.10%, 0.22% respectively and 2.88%, 0.0015%, 0.84% for urine. And the average BODs, COD, SS concentrations were 26,906 $mg/{\ell}$, 36,642 $mg/{\ell}$, 89,375 $mg/{\ell}$ respectively and 14,298 $mg/{\ell}$, 7,484 $mg/{\ell}$, 6,987 $mg/{\ell}$ for urine. In addition, the Cr, Cu, Ni, Cd, Pb, Zn concentrations of feces were 2.65 mg/kg, 7.05 mg/kg, 1.24 mg/kg, 0.07 mg/kg, 0.01 mg/kg, 45.11 mg/kg respectively and 1.52 mg/kg, 1.62 mg/kg, 0.00 mg/kg, 0.03 mg/kg, 0.03 mg/kg, 4.49 mg/kg for urine on the fresh matter basis. The end of the survey was that the quality of the compost can be used as a raw material, and manure is necessary to constantly driven forward horse manure composting research.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1257-1263
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• 2003

The modified engineering methodology and the modified electronic circuit in classical ultrasonic principles were applied to ultrasonic aerosol nebulizer for inhalation toxicology study of cadmium aerosol. 1532.96ppm Cd nebulizing solution was used to generate cadmium aerosol for particle size analysis with the modifying source and inlet temperatures. The results of particle size analysis for cadmium aerosol were as following. The highest particle counting for source temperature 20℃ was 399.75 × 10² in inlet temperature 100℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 50℃ was 399.70 × 10² in inlet temperature 50℃ and particle diameter 0.75㎛. The highest particle counting for source temperature 70℃ was 411.14 × 10² in inlet temperature 100℃ and particle diameter 0.75㎛. The ranges of geometric mean diameter were 0.74-0.79㎛ in source temperature 20℃, 0.65-0.72㎛ in source temperature 50℃, and 0.65-0.80㎛ in source temperature 70℃. The smallest geometric mean diameter was 0.65㎛ in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the largest geometric mean diameter was 0.80㎛ in source temperature 70℃ and inlet temperature 100℃. The ranges of geometric standard deviation were 1.71-1.80 in source temperature 20℃, 1.27-1.61 in source temperature 50℃, and 1.27-2.29 in source temperature 70℃. The lowest geometric standard deviation was 1.27 in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the highest geometric standard deviation was 2.29 in source temperature 70℃ and inlet temperature 100℃. Generated aerosol for cadmium inhalation toxicology study was polydisperse aerosol with the above geometric standard deviation 1.2. The ranges of mass median diameter(MMD) were 1.75-2.25㎛ in source temperature 20℃, 1.27-1.61㎛ in source temperature 50℃, and 1.27-2.29㎛ in source temperature 70℃. The smallest MMD was 1.27㎛ in source temperature 50, 70℃ and inlet temperature 20, 50℃, and the largest MMD was 2.29㎛ in source temperature 70℃ and inlet temperature 100℃. Cadmium chloride concentration in nebulizing solution affected the particle size and distribution of cadium aerosol in air. MMO for inhalation toxicology testing in OECD and EU is less than 3㎛ and EPA guidance is less than 4㎛. In our results, in source temperatures of 20, 50, 70℃, and inlet temperatures of 20, 50, 100, 150, 200, 250℃ were conformed to the those guidance.

• 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.

• Journal of the Korean GEO-environmental Society
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• v.17 no.9
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• pp.37-45
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• 2016

This study analyzes the environmental and durability problems of traditional (LW) grouting method. And the proposed method was compared to the others effects by analyzing the in-situ applicability and effect of performance of the method using the silica sol. This study analyzed the eco-friendly, effects of high strength silica sol through laboratory tests. The effects of the construction process were identified through the field tests. The compressive strength was increased by 1.3 times compared to the LW method and the shrinkage is 3~8 times less than that of LW method with water glass. No toxicity, which could affect soil contamination. In particular, it was confirmed that the Toxicity fish also survived with little pH change in the concentration tank. Also it confirmed the construction effects through field test. Field tests are a standard penetration test, permeability test, LLT, BST. Permeability was reduced to $1{\times}10^{-5{\sim}-6}cm/sec$.