• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.347-350
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• 2002

Arsenic speciation changes between As(V) and As(III) are subject to changes in accordance with redox conditions in the environment. It is common to find contaminated sites associated with mixed wastes including both organic pollutants and heavy metals. We conducted microcosm experiment under hypothesis that the co-disposed organic pollutants would influence on the arsenic forms and concentrations, via degradation of the organic pollutants and the consequent impact on the redox conditions in soil. Artificially contaminated soil samples were run for 40 days with control samples without artificial contamination. We noticed arsenic in the contaminated soil showed different behaviour compared with the arsenic in the control soil. The findings indicate degradation of organic pollutants in the contaminated soil influenced on the arsenic speciation and concentrations. A further work is needed to understand the process quantitatively. However, we could confirm that degradation of organic pollutants can influence on the abiotic processes associated with geochemical reactions in contaminated soil. Degradation of organic pollutants can increase the mobility and toxicity of arsenic in soil and sediment by changing redox conditions in the geological media and subsequently from As(V) to As(III).

• Journal of Applied Biological Chemistry
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• v.51 no.1
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• pp.36-44
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• 2008

Organic forms of arsenic (As) were determined through fractionation procedure of soil organic matter (SOM) in soil, sediments and mine tailing samples from the Myungbong, Dongil, and Okdong mining areas of southern Korea. An alkaline extraction method was applied to soil samples followed by the fractionation procedures of SOM by the DAX-8 and XAD-4 resin adsorption method. Major fraction of organic As species (42% to 98%) was found in acid-soluble fraction, whereas minor fraction (0.1 % to 67.8%) was present in the humic-associated As. In acid-soluble fractions, the transphillic- and hydrophilic-associated As were dominant in addition to As binding with humic and fulvic SOM. Arsenic binding was the strongest between pH 6 to 8 and reduced to about 70% at both low and high pH regions. The amount of both transphillic and hydrophillic associated As was less changed than humic and fulvic-associated As, in both low and high pH regions. This apparently indicates that As has stronger affinity towards hydrophillic rather than hydrophobic organics. From the experimental observation of As-binding SOM in natural soil, the ligand exchange model may be a feasible explanation of transphillic and hydrophillic affinity of As.

• Toxicological Research
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• v.24 no.3
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• pp.219-225
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• 2008

A screening study of the acute toxicity of organic arsenics such as arsenobetaine and arsenocholine, a product of arsenic methylation metabolite, and inorganic arsenic was carried out to examine hematological and serum biochemical parameters in cynomolgus monkeys(Macaca fascicularis). We found soft and liquid feces, and vomiting in all treated groups with inorganic and organic arsenics. The monkeys in inorganic arsenic-treated group showed a significant increase in vomiting frequency compared with those in three organic arsenics-treated groups. These results suggest that inorganic arsenic might be more toxic than three other organic arsenics tested. The monkeys in inorganic arsenic-treated group showed a decrease in platelet and an increase in monocyte on day 4 and the monkeys in arsenocholine-treated group showed an increase in reticulocyte percentage on day 8. The monkeys in inorganic-treated group also showed decreases in AST and ALT values and the monkeys in arsenobetaine-treated group showed a decrease in AST value and an increase in T-CHO value. However, these hematological and biochemical changes were within the physiological ranges, showing that the single dose of inorganic and organic arsenics did not affect at least hematological and serum biochemical parameters. The present study of toxicity with single dose of arsenics provides valuable indicators for longer term study of toxicity of repeated doses of arsenics in primates.

• Toxicological Research
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• v.18 no.2
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• pp.107-116
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• 2002

Arsenic (As) is a ubiquitous element found in several forms in foods and water. Although certain foods, such as marine fish, contain substantial levels of organic arsenic forms, they are relatively low in toxicity compared to inorganic forms. in contrast, arsenic in drinking water is predominantly inorganic and highly toxic. Chronic ingestion of arsenic-contaminated drinking water is therefore the major pathway posing potential risk to human hearth. since the early 1990s in Bangladesh ozone, arsenic exposure has caused more than 7,000 deaths and uncounted thousands shout symptoms of long-term arsenic poisoning. Significant portion of world populations are exposed to low to moderate levels of arsenic of parts per billion (ppb) to hundreds of ppb. As a consequence, the World Health Organization (WHO) and U.S. environmental health agencies, such as the Environmental Protection Agency (EPA) made arsenic their highest priority. Recently, the WHO, European Union (EU), and US. EPA lowered an acceptable level of 10 ppb for arsenic in drinking water In this article, various health effects of arsenic in drinking water were reviewed and the current status for risk assessment to regulate arsenic in drinking water was discussed.

• Journal of Environmental Health Sciences
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• v.49 no.5
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• pp.237-246
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• 2023

Background: Arsenic is a metalloid of public health significance due to its unique material properties and toxicity and the widespread pollution in the environment. Arsenic exists as inorganic arsenic and organic arsenic with distinct chemical properties. Its toxicity varies depending on the properties. Objectives: Although the carcinogenicity of arsenic has been identified, the various diseases that occur after acute and chronic exposure to arsenic are not yet clearly known. Methods: Research on the effects of chronic exposure to arsenic on human health was searched and the results were summarized. Results: It has been found that cancer occurs due to exposure to high concentrations of arsenic in areas with elevated exposure to arsenic, but research results have recently been presented on health effects caused by chronic exposure to low concentrations of arsenic. Cancers have also been identified to be related to inorganic arsenic, including skin cancer, lung cancer, and bladder cancer. Significant relationships with neurological diseases, cardiovascular diseases, and diabetes mellitus have been suggested as well. Conclusions: Our results suggest that it is necessary to evaluate the health impact on residents around abandoned metal mines and industrial complexes in South 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.

• Toxicological Research
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• v.24 no.3
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• pp.161-167
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• 2008

Recently, arsenic-toxicity has become the major focus of strenuous assessment and dynamic research from the academy and regulatory agency. To elucidate the cause and the mechanism underlying the serious adverse health effects from chronic ingestion of arsenic-contaminated drinking water, numerous studies have been directed on the investigation of arsenic-toxicity using various in vitro as well as in vivo systems. Neverthless, some questions for arsenic effects remain unexplained, reflecting the contribution of unknown factors to the manifestation of arsenic-toxicity. Interestingly, very recent studies on arsenic metabolites have discovered that trivalent methylated arsenicals show stronger cytotoxic and genotoxic potentials than inorganic arsenic or pentavalent metabolites, arguing that these metabolites could play a key role in arsenic-associated disorders. In this review, recent progress and literatures are summarized on the metabolism of trivalent methylated metabolites and their toxicity on body systems including cardiovascular system in an effort to provide an insight into the future research on arsenic-associated disorders.

• Journal of Environmental Science International
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• v.28 no.1
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• pp.99-106
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• 2019

Arsenic is among the heavy metals commonly found in aqueous environments. Iron oxide is known as an efficient adsorbent for the arsenic. A new synthetic method was applied to provide iron oxide giving a large specific surface area. The mixing method affects the formation of iron oxide. Ultrasonic waves assisted the formation of very fine iron oxide in an organic phase. The synthesized iron oxide is amorphous type with a high surface area of more than $181.3m^2/g$. Sorption capacity of the synthesized adsorbent was relatively very high for arsenic and varied depending on the oxidation state of arsenic: a higher capacity was obtained with As(V). Lower solution pH provided a higher sorption capacity for As(V). The competitive effect of co-exist anions such as chloride, nitrate, and sulfate was minimal in sorption capacity of the iron oxide for arsenic.

• 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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.318-322
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• 2004

Arsenic is a toxic and carcinogenic metalloid, whose sources in nature include mineral dissolution and volcanic eruption. Abandoned mines and hazardous waste disposal sites are another major source of arsenic contamination of soil and aquatic systems. To predict concentrations of the toxic inorganic arsenic in aqueous phase. the biogeochemical redox processes and transport behavior need to be studied together and be coupled in a reactive transport model. A new reaction module describing the fate and transport of inorganic arsenic species (As(II)), dissolved oxygen, nitrate, ferrous iron, sulfate, and dissolved organic carbon are developed and incorporated into the RT3D code.