• Environmental Analysis Health and Toxicology
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• v.29
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• pp.18.1-18.9
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• 2014

Objectives The purpose of this study was to determine a separation method for each arsenic metabolite in urine by using a high performance liquid chromatography (HPLC)-inductively coupled plasma-mass spectrometer (ICP-MS). Methods Separation of the arsenic metabolites was conducted in urine by using a polymeric anion-exchange (Hamilton PRP X-100, $4.6mm{\times}150mm$, $5{\mu}m$) column on Agilent Technologies 1260 Infinity LC system coupled to Agilent Technologies 7700 series ICP/MS equipment using argon as the plasma gas. Results All five important arsenic metabolites in urine were separated within 16 minutes in the order of arsenobetaine, arsenite, dimethylarsinate, monomethylarsonate and arsenate with detection limits ranging from 0.15 to $0.27{\mu}g/L$ ($40{\mu}L$ injection). We used G-EQUAS No. 52, the German external quality assessment scheme and standard reference material 2669, National Institute of Standard and Technology, to validate our analyses. Conclusions The method for separation of arsenic metabolites in urine was established by using HPLC-ICP-MS. This method contributes to the evaluation of arsenic exposure, health effect assessment and other bio-monitoring studies for arsenic exposure in South Korea.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.4
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• pp.449-457
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• 2016

In this study, the effectiveness of electrodialysis in removing inorganic arsenic from groundwater was investigated. To evaluate the feasibility of the electrodialysis, operating parameters such as treatment time, feed concentration, applied voltage and superficial velocity were experimentally investigated on arsenic removal. The higher conductivity removal and arsenic removal efficiency were obtained by increasing applied voltages and operation time. An increase of salinity concentrations in arsenic polluted groundwater exerted no effects on the arsenic separation ratios. Arsenic polluted waters were successfully treated with stack voltages of 1.8 ~ 2.4 V/cell-pair to approximately 93.4% of arsenic removal. Increase flow rate in diluate cell gave positive effect to removal rate. However, increase of superficial velocity in the concentrated cell exerted no effects on either the conductivity reduction or on the separation efficiency. Hopefully, this paper will provide direction in selecting appropriate operating conditions of electrodialysis for arsenic removal.

• Economic and Environmental Geology
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• v.57 no.3
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• pp.305-317
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• 2024

To investigate the effect of changes in microbial communities on arsenic release in soil, experiments were conducted on arsenic-contaminated soils (F1, G7, and G10). The experiments involved three groups of the experimental sets; ① BAC: sterilized soil + Bacillus fungorum, ② IND: indigenous bacteria, and ③ MIX: indigenous bacteria + B. fungorum, and incubated them for seven weeks using lactate as a carbon source under anaerobic conditions. The experimental results showed that higher concentrations of arsenic were released from the IND and MIX soils, where indigenous bacterial communities existed, compared to BAC. Significantly higher levels of arsenic were released from the G10 soil, which showed higher pH, compared to the F1 and G7 soils. In the G10 soil, unlike other soils, the proportion of As(III) among the released arsenic was also low. These results may be attributed to differences in microbial community composition that vary depending on the soil. By the seventh week, the diversity of microbial species in the IND and MIX soils had significantly decreased, with dominant orders such as Eubacteriales and Bacillales thriving. Bacteroidales in the seventh week of the MIX in the F1 soil, Rummeliibacillus in the seventh week of the IND and MIX of the G7 soil, and Enterobacterales in the IND and MIX of the G10 soil were dominant. At present, it is not known which mechanisms of microbial community changes affect the geochemical behavior of arsenic; however, these results indicate that microbiome in the soil may function as one of the factors regulating arsenic release.

• Journal of Evidence-Based Herbal Medicine
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• v.2 no.1
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• pp.33-42
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• 2009

Sodium arsenate and Yeonlyeonggobon-dan (nianlinggubendan) extract, a herbal restorative were treated p.o. 20mg/kg and 500mg/kg respectively and concurrently to rats, and examined the variation of the body weight and the accumulation of arsenic in organs. Yeonlyeonggobon-dan (nianlinggubendan) extract(YGD) resulted in the increase of body weight, and the increase ratio of body weight in arsenic-treated group was dropped but the group of concurrent administration with YGD showed significant recovery. The ratio of liver weight / body weight of arsenic-treated group increased but the group of concurrent administration with YGD showed significant decrease. The accumulation of arsenic in liver and kidney of arsenic-treated group increased but the group of concurrent administration with YGD showed significant decrease.

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.189-189
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• 2005

• Proceedings of the Membrane Society of Korea Conference
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• 1997.06a
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• pp.93-104
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• 1997

The objective of this study is to develop a method to reduce arsenic concentrations in contaminated water. This work is also aimed at increasing the specificity of membrane separation processes. Arsenic in contaminated waters is often present in the form of negatively charged oxyanions. These are relatively small molecules which cannot be separated directly by ultrafiltration. Oxyanions can be captured by polyelectrolytes and separated by ultrafiltration. Results will be presented on the use of two polyelectrolytes; polyethylenimine (PEI) and poly-diallyl dimethyl ammonium chloride (DADMAC) at various feed concentrations. A semi-continuous process utilizing PEI in a circulation loop was tested. The restfits indicate that better than 99.6 % recovery (permeate concentration < 0.001 $\mu$g/L) can be achieved based on an initial arsenic concentration of 300 $\mu$g/L. The results indicate that this treatment method is suitable as a main treatment process for drinking water or a polishing step after arsenic precipitation.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.1
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• pp.79-85
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• 2011

A study on characteristics for removal of arsenic ion using phosphorylated pine needles was performed. The surface condition of phosphorylated pine needles was confirmed by FT-IR, SEM(Scanning Electron Microscopy) and EDX(Energy Dispersive X-ray). The removal rate of arsenic ion was the highest as about 98% at pH 7. Most absorption for arsenic ion was also completed within 30min and decreased with time and pH of arsenic solution from 6.5 to 2.4.

• Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.3.1-3.8
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• 2019

The purpose of this study is to investigate the changes in growth, hematological parameters, and plasma components of juvenile starry flounder, Platichthys stellatus, following exposure to varying arsenic concentrations present at different water temperatures. P. stellatus (total length, $15.9{\pm}0.4cm$; body weight, $62.2{\pm}4.2g$) were exposed for 4 weeks to waterborne arsenic (sodium arsenite, As) at 0, 150, 300, and $600{\mu}g/L$ at temperatures of $12^{\circ}C$ and $18^{\circ}C$. Toxic effects of As exposure on P. stellatus were higher at the higher temperature and the growth and hematological parameters measured decreased with increasing arsenic concentration, while the concentration of plasma components measured increased. This indicates that waterborne As exposure and water temperature can cause toxic effects on growth, hematological parameters, and plasma components in Platichthys stellatus.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.33-44
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• 2009

The objective of the study was to develop a hybrid technology integrating biological and physicochemical technologies to efficiently remediate arsenic contaminated lands such as abandoned mine area. The tailing soil samples contaminated with As at a high level were obtained from Songchon abandoned mine, and the content of arsenic and heavy metals as well as physicochemical properties and mineral composition were investigated. In addition, two sets of sequential extraction methods were applied to analyze chemical speciations of arsenic and heavy metals to expect their leachability and mobility in geoenvironment. Based on these geochemical data of arsenic and heavy metal contaminants, column-type experiments on the bioleaching of arsenic were undertaken. Subsequently, experiments on the hybrid process incorporating bioleaching and electrokinetics were accomplished and its removal efficiency of arsenic was compared with that of the individual electrokinetic process. With the results, finally, the feasibilty of the hybrid technnology was evaluated. The arsenic removal efficiencies of the individual electrokinetic process (44 days) and the hybrid process incorporating bioleaching (28 days) and electrokinetics (16 dyas) were measured 57.8% and 64.5%, respectively, when both two processes were operated in an identical condition. On the contrary, the arsenic removal efficiency during the bioleaching process (28 days) appeared relatively lower (11.8%), and the result indicates that the bioleaching process enhanced the efficacy of the electrokinetic process as a result of mobilization of arsenic rather than removed arsenic by itself. In particular, the arsenic removal rate of the electrokinetics integrated with bioleaching was observed over than 2 times larger than that obtained by the electrokinetics alone. From the results of the study, if the bioleaching which is considered a relatively economic process is applied sufficiently prior to electrokinetics, the removal efficiency and rate of arsenic can be significantly improved. Consequently, the study proves the feasibility of the hybrid process integrating both technologies.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.812-821
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• 2007

The ecosystems of certain abandoned mines contain arsenic-resistant bacteria capable of performing detoxification when an ars gene is present in the bacterial genome. The ars gene has already been isolated from Pseudomonas putida and identified as a member of the membrane transport regulatory deoxyribonucleic acid family. The arsenite-oxidizing bacterial strains isolated in the present study were found to grow in the presence of 66.7 mM sodium arsenate($V;\;Na_2HAsO_4{\cdot}7H_2O$), yet experienced inhibited growth when the sodium arsenite($III;\;NaAsO_2$) concentration was higher than 26 mM. Batch experiment results showed that Pseudomonas putida strain OS-5 completely oxidized 1 mM of As(III) to As(V) within 35 h. An arsB gene encoding a membrane transport regulatory protein was observed in arsenite-oxidizing Pseudomonas putida strain OS-5, whereas arsB, arsH, and arrA were detected in strain OS-19, arsD and arsB were isolated from strain RW-18, and arsR, arsD, and arsB were found in E. coli strain OS-80. The leader gene of arsR, -arsD, was observed in a weak acid position. Thus, for bacteria exposed to weak acidity, the ars system may cause changes to the ecosystems of As-contaminated mines. Accordingly, the present results suggest that arsR, arsD, arsAB, arsA, arsB, arsC, arsH, arrA, arrB, aoxA, aoxB, aoxC, aoxD, aroA, and aroB may be useful for arsenite-oxidizing bacteria in abandoned arsenic-contaminated mines.