• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.129-130
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• 2005

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.55-59
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• 2003

The fixation and leaching characteristics of chromated copper arsenate (CCA Type C) and chromium- copper-fluoride-zinc (CCFZ) in domestic softwood (Japanese red pine, Korean pine, and Japanese larch) sapwood were investigated using the expressate method to follow chromium fixation and the American Wood-Preservers' Association (AWPA) leaching procedure to determine leaching properties after fixation. The rates of fixation were affected by preservative types; CCA was fixed much faster than CCFZ for all species evaluated. There were definite differences in the fixation rates of different species, with Korean pine requiring shorter to fix than the other species evaluated. Chromium fixation was greatly enhanced by elevated temperatures, and fixation time can be estimated according to fixation temperatures applied. The percentage of arsenic and zinc leached from domestic softwoods was relatively high compared to chromium and copper, indicating that there is still a relatively high unfixed arsenic and zinc components after complete chromium fixation in CCA-and CCFZ-treated samples, respectively.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.266-272
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• 2010

The present study was carried out to assess exposure & risk for Korean by total and inorganic As intake through agricultural products. Total arsenic analysis was performed using microwave device and ICP-MS. 50% MeOH extraction and anion-exchange HPLC-ICP-MS method has been used to determine arsenic species. 329 samples covering 20 kinds of agricultural products were collected from various retail outlets and markets across Korea. The concentration of total As was in the range of 0.001~0.718 mg/kg, while inorganic and organic arsenic species in all samples was not determined. For risk assessment, probable daily intake was calculated and compared with provisional tolerable weekly intake (PTWI, 15 ${\mu}g$/kg b.w./week for inorganic arsenic) established by JECFA. The median daily exposure to total and inorganic As by intake of agricultural products except rice was ranged 0.0002~0.012, 0.0001~0.001 ${\mu}g$/kg b.w./day, corresponding to 0.01~0.5%, 0.002~0.1% of PTWI, respectively. The median level of total and inorganic As intake through rice was 0.603 and 0.041 ${\mu}g$/kg b.w./day, and 28.1% and 1.9% of PTWI, respectively. Therefore, the level of overall exposure to arsenic for Korean through agricultural products was below the recommended JECFA levels, indicating of least possibility of risk.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.175-177
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• 2005

Effect of arsenite, arsenate and dimethylarsinic acid (DMA) on the growth of seedling plants were investigated in order to compare the toxicity of arsenic species in soil environments. Test plants were mung bean (Phaseolus radiatus), wheat (Triticum aestivum), barely (Hordeum vulgare), cucumber (Cucumis sativus L.). Seedling growth in As-contaminated soil were significantly reduced in all test species. Arsenite was more toxic than arsenate and DMA. Among the test plants, mung bean was most sensitive to arsenic, followed by cucumber, wheat, and barely.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.189-195
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• 2019

In this study, we performed an analysis of the accumulation of inorganic arsenic and growth rate with changes in phosphate concentration in Hizikia fusiforme. When exposed to inorganic arsenic for fourteen days, we found that the collection of inorganic arsenic hardly increased at high phosphate concentrations (2 mg L^-1). However, when the phosphate concentration was low (0.02 mg L^-1), accumulation of inorganic arsenic increased. Additionally, H. fusiforme decreased in a growth rate of 14.5% in low phosphate concentration (0.02 mg L^-1) and fell in a growth rate of 30% when exposed to inorganic arsenic (10 ㎍ L^-1). H. fusiforme cannot distinguish between phosphate and inorganic arsenic. Thus, when phosphate concentration was lower, the inorganic arsenic accumulation increased, and accumulated inorganic arsenic inhibited photosynthesis and cell division, reducing the growth rate. H. fusiforme is known to have higher inorganic arsenic accumulation than other seaweeds. Therefore, various studies are needed to secure the food safety of H. fusiforme which is an essential aquaculture species in Korea.

• Economic and Environmental Geology
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• v.38 no.1
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• pp.23-31
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• 2005

This study was performed to investigate the effect of humic acid on the adsorption of arsenic onto hematite and its binding mechanism through the chemical speciation modeling in the binary system and the adsorption modeling in the ternary system. The complexation modeling of arsenic and humic acid was suitable for the binding model with the basis of the electrostatic repulsion and the effect of bridging metal. In comparison with the experimental adsorption data in the ternary system, the competitive adsorption model from the binary intrinsic equilibrium constants was consistent with the amount of arsenic adsorption. However, the additive rule showed the deviation of model in the opposite way of cationic heavy metals, because the reduced organic complexation of arsenic and the enhanced oxyanionic competition diminished the adsorption of arsenic. In terms of the reaction mechanism, the organic complex of arsenic, neutral As(III) and oxyanionic As(V) species were transported and adsorbed competitively to the hematite surface forming the inner-sphere complex in the presence of humic acid.

• Journal of Environmental Health Sciences
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• v.42 no.3
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• pp.224-233
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• 2016

Objectives: The purpose of this study was to evaluate the relationship between residential surroundings, such as a power plant, steel mill and petrochemical facilities, and urinary arsenic concentrations in Chungcheongnam-do Province, Korea. Methods: Stratified by fish consumption and residential district, median and maximum block sampling was applied. A total of 346 spot urine samples were speciated for $As^{5+}$, $As^{3+}$, monomethylarsonic acid(MMA), dimethylarsonic acid (DMA) and arsenobetaine (AsB). Exposure assessment was based on questionnaires including data on sex, age, current tobacco use, fish consumption, type of water consumed, and occupational category. Results: Urinary $As^{5+}+As^{3+}+MMA+DMA$ concentrations of people living in the vicinity of a power plant ($GM=50.39{\mu}g/g$) were 61% higher than those of people living in the inland area according to median block sampling. Urinary $As^{5+}+As^{3+}+MMA+DMA+AsB$ concentrations of people living in the vicinity of industrial complex area were higher than those of people living in the inland area according to block sampling by median and maximum. Conclusion: Urinary arsenic concentrations of people living in vulnerable areas such as around industrial complexes, especially power plants, were higher than those of people living in an inland area.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3077-3083
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• 2010

The electrochemical detection of As(III) was investigated on a platinum-iron(III) nanoparticles modified multiwalled carbon nanotube on glassy carbon electrode(nanoPt-Fe(III)/MWCNT/GCE) in 0.1 M $H_2SO_4$. The nanoPt-Fe(III)/MWCNT/GCE was prepared via continuous potential cycling in the range from -0.8 to 0.7 V (vs. Ag/AgCl), in 0.1 M KCl solution containing 0.9 mM $K_2PtCl_6$ and 0.6 mM $FeCl_3$. The Pt nanoparticles and iron oxide were co-electrodeposited into the MWCNT-Nafion composite film on GCE. The resulting electrode was examined by cyclic voltammetry (CV), scanning electron microscopy (SEM), and anodic stripping voltammetry (ASV). For the detection of As(III), the nanoPt-Fe(III)/MWCNT/GCE showed low detection limit of 10 nM (0.75 ppb) and high sensitivity of $4.76\;{\mu}A{\mu}M^{-1}$, while the World Health Organization's guideline value of arsenic for drinking water is 10 ppb. It is worth to note that the electrode presents no interference from copper ion, which is the most serious interfering species in arsenic detection.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5191-5197
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• 2015

A partial response or resistance to chemotherapeutic agents is considered as a main obstacle in treatment of patients with cancer, including breast cancer. Refining taxane-based treatment procedures using adjuvant or combination treatment is a novel strategy to increase the efficiency of chemotherapy. PPM1D is a molecule activated by reactive oxygen species. whose expression is reported to modulate the recruitment of DNA repair molecules. In this study we examined the impact of arsenic trioxide on efficacy of paclitaxel-induced apoptosis in paclitaxel-resistant MCF-7 cells. We also investigated the expression of PPM1D and TP53 genes in response to this combination treatment. Resistant cells were developed from the parent MCF-7 cell line by applying increasing concentrations of paclitaxel. MTT assays were applied to determine the rate of cell survival. DAPI staining using fluorescent microscopy was employed to study apoptotic bodies. Real-time RT-PCR analysis was also applied to determine PPM1D mRNA levels. Our results revealed that combination of arsenic trioxide and paclitaxel elevates the efficacy of the latter in induction of apoptosis in MCF-7/PAC resistant cells. Applying arsenic trioxide also caused significant decreases in PPM1D mRNA levels (p<0.05). Our findings suggest that arsenic trioxide increases paclitaxel-induced apoptosis by down regulation of PPM1D expression. PPM1D dependent signaling can be considered as a novel target to improve the efficacy of chemotherapeutic agents in resistant breast cancer cells.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.1-10
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• 2020

Objectives: This study intends to evaluate the ecological risk of lead (Pb), arsenic (As), and their compounds according to the 2010 action plan on inventory and management for national priority chemicals and provide calculations of risks to the environment. By doing so, we aim to inform risk management measures for the target chemicals. Methods: We conducted species sensitivity distribution (SSD) analysis using the collected ecotoxicity data and obtained predicted no effect concentrations (PNECs) for the in-water environment using a hazardous concentration of 5% (HC5) protective of most species (95%) in the environment. Based on the calculated PNECs for aquatic organisms, PNEC values for soil and sediment were calculated using the partition coefficient. We also calculated predicted exposure concentration (PEC) from nation-wide environmental monitoring data and then the hazard quotient (HQ) was calculated using PNEC for environmental media. Results: Ecological toxicity data was categorized into five groups and five species for Pb and four groups and four species for As. Based on the HC5 values from SSD analysis, the PNEC value for aquatic organisms was calculated as 0.40 ㎍/L for Pb and 0.13 ㎍/L for As. PNEC values for soil and sediment calculated using a partition coefficient were 77.36 and 350.50 mg/kg for Pb and 24.20 and 112.75 mg/kg for As. The analysis of national environmental monitoring data showed that PEC values in water were 0.284 ㎍/L for Pb and 0.024 ㎍/L for As, while those in soil and sediment were respectively 45.9 and 44 mg/kg for Pb, and 11.40 and 19.80 mg/kg for As. Conclusions: HQs of Pb and As were 0.70 and 0.18 in water, while those in soil and sediment were 0.59 and 0.13 for Pb and 0.47 and 0.18 for As. With HQs <1 of lead and arsenic in the environment, their ecological risk levels are found to be low.