Arsenic activation analysis of freshwater fish through the precipitation of elemental arsenic

International Nuclear Information System (INIS)

Comparetto, G.M.; Jester, W.A.; Skinner, W.F.

1982-01-01

The activation analysis of trace elements of arsenic in biological samples is complicated by the interference of a 82 Br photo peak (554KeV) and the compton continuum with the major 76 As photo peak of 559 KeV. In addition, the half-lives of 24 Na, 82 Br, and 76 As are too similar to be resolved by varying irradiation and/or decay times. Thus post irradiation chemical separation of arsenic is often required. A study of existing radiochemistry techniques reported in the literature found that existing methods were complex x and/or lengthy. In this work, a more rapid and less extensive method was required to analyze a large number of fish samples exposed to fly ash sluice water from coalburning power plant. A method has been developed which involves the dissolution of irradiated homogenized fish samples, the addition of an arsenic carrier, and the reduction of arsenic to the +3 state. Arsenic is then precipitated as elemental arsenic. An important factor in this work was the discovery that this procedure produced arsenic yields of 81+-3% for both the fish samples and the NBC Orchard leaves standard employed in this analysis. Thus the determination of absolute arsenic yields is not required. This method has been used to analyze 32 of the fish samples the average arsenic content of which was found to vary between 0.08 and 4.8 ppm. (author)

Mouse arsenic (+3 oxidation state) methyltransferase genotype affects metabolism and tissue dosimetry of arsenicals after arsenite administration in drinking water.

Science.gov (United States)

Chen, Baowei; Arnold, Lora L; Cohen, Samuel M; Thomas, David J; Le, X Chris

2011-12-01

Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes methylation of inorganic arsenic (iAs) producing a number of methylated arsenic metabolites. Although methylation has been commonly considered a pathway for detoxification of arsenic, some highly reactive methylated arsenicals may contribute to toxicity associated with exposure to inorganic arsenic. Here, adult female wild-type (WT) C57BL/6 mice and female As3mt knockout (KO) mice received drinking water that contained 1, 10, or 25 ppm (mg/l) of arsenite for 33 days and blood, liver, kidney, and lung were taken for arsenic speciation. Genotype markedly affected concentrations of arsenicals in tissues. Summed concentrations of arsenicals in plasma were higher in WT than in KO mice; in red blood cells, summed concentrations of arsenicals were higher in KO than in WT mice. In liver, kidney, and lung, summed concentrations of arsenicals were greater in KO than in WT mice. Although capacity for arsenic methylation is much reduced in KO mice, some mono-, di-, and tri-methylated arsenicals were found in tissues of KO mice, likely reflecting the activity of other tissue methyltransferases or preabsorptive metabolism by the microbiota of the gastrointestinal tract. These results show that the genotype for arsenic methylation determines the phenotypes of arsenic retention and distribution and affects the dose- and organ-dependent toxicity associated with exposure to inorganic arsenic.

Arsenic removal for ceramic water filters

Directory of Open Access Journals (Sweden)

Mishant Kumar

2013-02-01

Full Text Available Arsenic in drinking water is a hazard to human health and is a known carcinogen (Mass 1992. Resource Development International – Cambodia (RDIC has researched, developed, and manufactured simple ceramic water fi lters (CWF which have proved to be extremely effective in removing pathogens from water. These fi lters however, do not remove arsenic from water, which exists in the source water at levels above the World Health Organisation (WHO guideline of 10μg/L. The aims of this literature based study were to investigate conventional and non-conventional arsenic removal processes, and to discuss the options for applying an arsenic removal technology to the CWFs produced by RDIC. It was found that conventional arsenic removal technologies are diffi cult to implement in the context of household water treatment in a developing country. This study suggested that non-conventional arsenic removal technologies shall be more effective and that field studies must be undertaken to verify the success of such methods.

Poisoning by coal smoke containing arsenic and fluoride

Energy Technology Data Exchange (ETDEWEB)

An, D.; He, Y.G.; Hu, Q.X. [Guizhou Sanitary and Epidemiological Station, Guiyang (China)

1997-02-01

An investigation was made into a disease involving skin pigmentation, keratosis of the hands and feet, dental discoloration, and generalized bone and joint pain, stiffness and rigidity, in the village of Bazhi, Zhijin County, Ghizhou Province, People`s Republic of China. Measurements were made of the arsenic and fluoride levels of coal, water, air, food, urine and hair in Bazhi and a control village, Xinzhai, in which coal with a low arsenic content was used. Up to 188 people, including children, in Bazhi and 752 in Xinzhai, were examined for the presence of chronic arsenium, skeletal fluorosis, dental fluorosis and electrocardiogram abnormalities. The coal in Bazhi was found to contain high levels of arsenic and fluoride resulting, after burning in homes without an adequate chimney systems, in pollution of air and food with arsenic and fluoride. The coal in Xinzhai did not cause arsenic pollution but did produce a higher level of fluoride pollution. It was concluded that the endemic disease in Bazhi was caused by pollution by coal smoke containing arsenic and fluoride. It is suggested that arsenic may act synergistically with fluoride so that a lower level of fluoride may produce fluoride toxicity with dental and skeletal fluorosis.

Developmental and reproductive toxicity of inorganic arsenic: animal studies and human concerns.

Science.gov (United States)

Golub, M S; Macintosh, M S; Baumrind, N

1998-01-01

Information on the reproductive and developmental toxicity of inorganic arsenic is available primarily from studies in animals using arsenite and arsenate salts and arsenic trioxide. Inorganic arsenic has been extensively studied as a teratogen in animals. Data from animal studies demonstrate that arsenic can produce developmental toxicity, including malformation, death, and growth retardation, in four species (hamsters, mice, rats, rabbits). A characteristic pattern of malformations is produced, and the developmental toxicity effects are dependent on dose, route, and the day of gestation when exposure occurs. Studies with gavage and diet administration indicate that death and growth retardation are produced by oral arsenic exposure. Arsenic is readily transferred to the fetus and produces developmental toxicity in embryo culture. Animal studies have not identified an effect of arsenic on fertility in males or females. When females were dosed chronically for periods that included pregnancy, the primary effect of arsenic on reproduction was a dose-dependent increase in conceptus mortality and in postnatal growth retardation. Human data are limited to a few studies of populations exposed to arsenic from drinking water or from working at or living near smelters. Associations with spontaneous abortion and stillbirth have been reported in more than one of these studies, but interpretation of these studies is complicated because study populations were exposed to multiple chemicals. Thus, animal studies suggest that environmental arsenic exposures are primarily a risk to the developing fetus. In order to understand the implications for humans, attention must be given to comparative pharmacokinetics and metabolism, likely exposure scenarios, possible mechanisms of action, and the potential role of arsenic as an essential nutrient.

Development of reference material for proficiency tests: arsenic in fish tissue

International Nuclear Information System (INIS)

Santana, Luciana Vieira de; Sarkis, Jorge E.S.; Ulrich, Joao C.; Hortellani, Marcos Antonio

2013-01-01

Proficiency tests (PT) are extensively used to evaluate the analytical competence of laboratories, and are also used as a part of accreditation processes. For this reason are important tool for quality control of laboratories including laboratories that act directly with food exporting companies. In Brazil there are no providers of proficiency testing for toxic metals, such as arsenic in fish tissue. This study presents a protocol to produce reference material to be used in proficiency test for arsenic in fish tissue following the recommendations of the ISO Guide 35. The preparation scheme consisted of: selecting of individuals, cleaning of scale and skin, trituration, homogenization, and spiking with arsenic at two levels of concentration. The mixture was then irradiated in a cyclotron Cyclone 30 Applications ion beam with cobalt 60 at 10.00 ± 1.05 KGy, before being packed into sachets. To verify the efficacy of the irradiation procedure, 26 (randomly selected) irradiated sachets and 26 non-irradiated sachets were assessed for homogeneity and stability. The results indicate that irradiation with cobalt 60 is crucial for ensuring the preservation of the integrity of the material, providing stable material at room temperature for 2 months. The samples can therefore be transported at room temperature. (author)

Development of reference material for proficiency tests: arsenic in fish tissue

Energy Technology Data Exchange (ETDEWEB)

Santana, Luciana Vieira de; Sarkis, Jorge E.S.; Ulrich, Joao C.; Hortellani, Marcos Antonio, E-mail: santana-luciana@ig.com.br, E-mail: jesarkis@ipen.br, E-mail: jculrich@ipen.br, E-mail: mahortel@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Proficiency tests (PT) are extensively used to evaluate the analytical competence of laboratories, and are also used as a part of accreditation processes. For this reason are important tool for quality control of laboratories including laboratories that act directly with food exporting companies. In Brazil there are no providers of proficiency testing for toxic metals, such as arsenic in fish tissue. This study presents a protocol to produce reference material to be used in proficiency test for arsenic in fish tissue following the recommendations of the ISO Guide 35. The preparation scheme consisted of: selecting of individuals, cleaning of scale and skin, trituration, homogenization, and spiking with arsenic at two levels of concentration. The mixture was then irradiated in a cyclotron Cyclone 30 Applications ion beam with cobalt 60 at 10.00 ± 1.05 KGy, before being packed into sachets. To verify the efficacy of the irradiation procedure, 26 (randomly selected) irradiated sachets and 26 non-irradiated sachets were assessed for homogeneity and stability. The results indicate that irradiation with cobalt 60 is crucial for ensuring the preservation of the integrity of the material, providing stable material at room temperature for 2 months. The samples can therefore be transported at room temperature. (author)

Removal of arsenic from drinking water by natural adsorbents

OpenAIRE

MD SHAHNOOR ALAM KHAN

2017-01-01

The presence of arsenic in groundwater has been reported in many countries across the world and it is a serious threat to public health. The aim of this study was to identify prospective natural materials with high arsenic adsorption capacity and durable hydraulic property to produce adequate flow of water. The comparative study identified Skye sand as the best natural adsorbent. The prototype household filter with Skye sand achieved complete removal of arsenic and iron. Arsenic removal by du...

Application of colloidal gas aphron suspensions produced from Sapindus mukorossi for arsenic removal from contaminated soil.

Science.gov (United States)

Mukhopadhyay, Soumyadeep; Mukherjee, Sumona; Hashim, Mohd Ali; Sen Gupta, Bhaskar

2015-01-01

Colloidal gas aphron dispersions (CGAs) can be described as a system of microbubbles suspended homogenously in a liquid matrix. This work examines the performance of CGAs in comparison to surfactant solutions for washing low levels of arsenic from an iron rich soil. Sodium Dodecyl Sulfate (SDS) and saponin, a biodegradable surfactant, obtained from Sapindus mukorossi or soapnut fruit were used for generating CGAs and solutions for soil washing. Column washing experiments were performed in down-flow and up flow modes at a soil pH of 5 and 6 using varying concentration of SDS and soapnut solutions as well as CGAs. Soapnut CGAs removed more than 70% arsenic while SDS CGAs removed up to 55% arsenic from the soil columns in the soil pH range of 5-6. CGAs and solutions showed comparable performances in all the cases. CGAs were more economical since it contains 35% of air by volume, thereby requiring less surfactant. Micellar solubilization and low pH of soapnut facilitated arsenic desorption from soil column. FT-IR analysis of effluent suggested that soapnut solution did not interact chemically with arsenic thereby facilitating the recovery of soapnut solution by precipitating the arsenic. Damage to soil was minimal arsenic confirmed by metal dissolution from soil surface and SEM micrograph. Copyright © 2014 Elsevier Ltd. All rights reserved.

Treatability of inorganic arsenic and organoarsenicals in groundwater

International Nuclear Information System (INIS)

Kuhlmeier, P.D.; Sherwood, S.P.

1996-01-01

A 2-year three-phase study into methods for treatment of mixed inorganic and organic arsenic species to drinking water levels was conducted at a former pesticide facility in Houston, Tex. The species present include monomethylarsinic acid, dimethylarsinic acid, arsenate, and arsenite. Phase One studies reported here included the evaluation of four adsorbents using bottle roll and column flow through techniques, oxidation through the application of Fenton's reagent followed by coprecipitation, coprecipitation without oxidation, and ultraviolet (UV)/ozone tests. The four adsorbents tested were activated carbon, activated alumina, ferrous sulfide, and a strongly basic ion exchange resin. All adsorbents removed some arsenic, but none except ferrous sulfide was sufficiently effective to warrant follow-up studies. Two small ferrous sulfide column tests, run under different conditions, removed arsenic but not to the levels and loading capacities needed to make this method practical. Organic compound destruction was tested using Fenton's reagent (a mixture of hydrogen peroxide and ferrous iron) before coprecipitation. Arsenic was reduced to 170 ppb in the treated liquor. Coprecipitation without oxidative pretreatment produced a liquor containing 260 ppb arsenic. A two-stage Fenton-type coprecipitation procedure produced a supernatant containing 110 ppb total arsenic. Preliminary tests with a second-stage oxidative process, using ozone and UV radiation, showed approximately 80% destruction of an organic-arsenic surrogate (cacodylic acid) in 1 hour

Correlation of Breastmilk Arsenic With Maternal, Infant Urinary Arsenic and Drinking Water Arsenic in an Arsenic Affected Area of Bangladesh

Science.gov (United States)

Alauddin, M.; Islam, M. R.; Milton, A. H.; Alauddin, S. T.; Mouly, T.; Behri, E.; Ayesha, A.; Akter, S.; Islam, M. M.

2016-12-01

About 97% of population in Bangladesh depend on groundwater as the principle source of drinking water and this water is highly contaminated with inorganic arsenic. Consumption of arsenic contaminated drinking water by pregnant women raises the prospect of early life exposure to inorganic arsenic for newborn which may be lead to adverse health effect in later life. This work was carried out in parts of Gopalganj district in Bangladesh, a region affected by arsenic contamination in groundwater. The objective of the work was to assess potential early life exposure to arsenic for infants through breastfeeding by mothers who were drinking water with arsenic levels ranging from 100 to 300 µg/l. A cohort of 30 mother-baby pairs were selected for the current study. Breastmilk samples from mothers, urine samples from each pair of subjects at 1, 6 and 9 month age of infant were collected and total arsenic were determined in these samples. In addition speciation of urinary arsenic and metabolites were carried out in 12 mother-baby pairs. Median level for breastmilk arsenic were 0.50 µg/l. Urinary arsenic of infants did not correlate with breastmilk arsenic with progressing age of infants. Maternal and infant urinary total arsenic at 1 month age of infant showed some positive correlation (r = 0.39). In infant urine major metabolite were dimethyl arsenic acid (DMA) (approximately 70%) indicating good methylating capacity for infants at 1 and 6 months of age. In conclusion, infants were not exposed to arsenic through breastfeeding even though mothers were exposed to significant levels of arsenic through drinking water.

Arsenic speciation in food chains from mid-Atlantic hydrothermal vents

Science.gov (United States)

Taylor, Vivien F.; Jackson, Brian P.; Siegfried, Matthew R.; Navratilova, Jana; Francesconi, Kevin A.; Kirshtein, Julie; Voytek, Mary

2012-01-01

Arsenic concentration and speciation were determined in benthic fauna collected from the Mid-Atlantic Ridge hydrothermal vents. The shrimp species, Rimicaris exoculata, the vent chimney-dwelling mussel, Bathymodiolus azoricus, Branchipolynoe seepensis, a commensal worm of B. azoricus and the gastropod Peltospira smaragdina showed variations in As concentration and in stable isotope (δ13C and δ15N) signature between species, suggesting different sources of As uptake. Arsenic speciation showed arsenobetaine to be the dominant species in R. exoculata, whereas in B. azoricus and B. seepensis arsenosugars were most abundant, although arsenobetaine, dimethylarsinate and inorganic arsenic were also observed, along with several unidentified species. Scrape samples from outside the vent chimneys covered with microbial mat, which is a presumed food source for many vent organisms, contained high levels of total As, but organic species were not detectable. The formation of arsenosugars in pelagic environments is typically attributed to marine algae, and the pathway to arsenobetaine is still unknown. The occurrence of arsenosugars and arsenobetaine in these deep sea organisms, where primary production is chemolithoautotrophic and stable isotope analyses indicate food sources are of vent origin, suggests that organic arsenicals can occur in a foodweb without algae or other photosynthetic life.

Arsenic speciation in food chains from mid-Atlantic hydrothermal vents.

Science.gov (United States)

Taylor, Vivien F; Jackson, Brian P; Siegfried, Matthew; Navratilova, Jana; Francesconi, Kevin A; Kirshtein, Julie; Voytek, Mary

2012-05-04

Arsenic concentration and speciation were determined in benthic fauna collected from the Mid-Atlantic Ridge hydrothermal vents. The shrimp species, Rimicaris exoculata , the vent chimney-dwelling mussel, Bathymodiolus azoricus , Branchipolynoe seepensis , a commensal worm of B. azoricus , and the gastropod Peltospira smaragdina showed variations in As concentration and in stable isotope (δ 13 C and δ 15 N) signature between species, suggesting different sources of As uptake. Arsenic speciation showed arsenobetaine to be the dominant species in R. exoculata , whereas in B. azoricus and B. seepensis arsenosugars were most abundant, although arsenobetaine, dimethylarsinate, and inorganic arsenic were also observed, along with several unidentified species. Scrape samples from outside the vent chimneys, covered with microbial mat, which is a presumed food source for many vent organisms, contained high levels of total As, but organic species were not detectable. The formation of arsenosugars in pelagic environments is typically attributed to marine algae, and the pathway to arsenobetaine is still unknown. The occurrence of arsenosugars and arsenobetaine in these deep sea organisms, where primary production is chemolithoautotrophic and stable isotope analyses indicate food sources are of vent origin, suggests that organic arsenicals can occur in a food web without algae or other photosynthetic life.

Identification of an S-adenosylmethionine (SAM) dependent arsenic methyltransferase in Danio rerio

Energy Technology Data Exchange (ETDEWEB)

Hamdi, Mohamad [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States); Yoshinaga, Masafumi; Packianathan, Charles; Qin, Jie [Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, FL33199 (United States); Hallauer, Janell; McDermott, Joseph R. [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States); Yang, Hung-Chi [Department of Medical Biotechnology and Laboratory Sciences, Chang-Gung University, Tao-Yuan, Kwei-San 333, Taiwan (China); Tsai, Kan-Jen [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Liu, Zijuan, E-mail: liu2345@oakland.edu [Department of Biological Sciences, Oakland University, Rochester, MI 48309 (United States)

2012-07-15

Arsenic methylation is an important cellular metabolic process that modulates arsenic toxicity and carcinogenicity. Biomethylation of arsenic produces a series of mono-, di- and tri-methylated arsenic metabolites that can be detected in tissues and excretions. Here we report that zebrafish exposed to arsenite (As{sup III}) produces organic arsenicals, including MMA{sup III}, MMA{sup V} and DMA{sup V} with characteristic tissue ratios, demonstrating that an arsenic methylation pathway exists in zebrafish. In mammals, cellular inorganic arsenic is methylated by a SAM-dependent arsenic methyltransferase, AS3MT. A zebrafish arsenic methyltransferase homolog, As3mt, was identified by sequence alignment. Western blotting analysis showed that As3mt was universally expressed in zebrafish tissues. Prominent expression in liver and intestine correlated with methylated arsenic metabolites detected in those tissues. As3mt was expressed in and purified from Escherichia coli for in vitro functional studies. Our results demonstrated that As3mt methylated As{sup III} to DMA{sup V} as an end product and produced MMA{sup III} and MMA{sup V} as intermediates. The activity of As3mt was inhibited by elevated concentrations of the substrate As{sup III} as well as the metalloid selenite, which is a well-known antagonistic micronutrient of arsenic toxicity. The activity As3mt was abolished by substitution of either Cys160 or Cys210, which corresponds to conserved cysteine residues in AS3MT homologs, suggesting that they are involved in catalysis. Expression in zebrafish of an enzyme that has a similar function to human and rodent orthologs in catalyzing intracellular arsenic biomethylation validates the applicability of zebrafish as a valuable vertebrate model for understanding arsenic-associated diseases in humans. -- Highlights: ► Zebrafish methylated As{sup III} to MMA{sup III}, MMA{sup V} and DMA{sup V}. ► A zebrafish arsenic methyltransferase (As3mt) was purified in E. coli. �

Investigating the biogeochemical interactions involved in simultaneous TCE and Arsenic in situ bioremediation

Science.gov (United States)

Cook, E.; Troyer, E.; Keren, R.; Liu, T.; Alvarez-Cohen, L.

2016-12-01

The in situ bioremediation of contaminated sediment and groundwater is often focused on one toxin, even though many of these sites contain multiple contaminants. This reductionist approach neglects how other toxins may affect the biological and chemical conditions, or vice versa. Therefore, it is of high value to investigate the concurrent bioremediation of multiple contaminants while studying the microbial activities affected by biogeochemical factors. A prevalent example is the bioremediation of arsenic at sites co-contaminated with trichloroethene (TCE). The conditions used to promote a microbial community to dechlorinate TCE often has the adverse effect of inducing the release of previously sequestered arsenic. The overarching goal of our study is to simultaneously evaluate the bioremediation of arsenic and TCE. Although TCE bioremediation is a well-understood process, there is still a lack of thorough understanding of the conditions necessary for effective and stable arsenic bioremediation in the presence of TCE. The objective of this study is to promote bacterial activity that stimulates the precipitation of stable arsenic-bearing minerals while providing anaerobic, non-extreme conditions necessary for TCE dechlorination. To that end, endemic microbial communities were examined under various conditions to attempt successful sequestration of arsenic in addition to complete TCE dechlorination. Tested conditions included variations of substrates, carbon source, arsenate and sulfate concentrations, and the presence or absence of TCE. Initial arsenic-reducing enrichments were unable to achieve TCE dechlorination, probably due to low abundance of dechlorinating bacteria in the culture. However, favorable conditions for arsenic precipitation in the presence of TCE were eventually discovered. This study will contribute to the understanding of the key species in arsenic cycling, how they are affected by various concentrations of TCE, and how they interact with the key

Binational Arsenic Exposure Survey: Methodology and Estimated Arsenic Intake from Drinking Water and Urinary Arsenic Concentrations

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Robin B. Harris

2012-03-01

Full Text Available The Binational Arsenic Exposure Survey (BAsES was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and Sonora, Mexico. Adults responded to questionnaires and provided dietary information. A first morning urine void and water from all household drinking sources were collected. Associations between urinary arsenic concentration (total, organic, inorganic and estimated level of arsenic consumed from water and other beverages were evaluated through crude associations and by random effects models. Median estimated total arsenic intake from beverages among participants from Arizona communities ranged from 1.7 to 14.1 µg/day compared to 0.6 to 3.4 µg/day among those from Mexico communities. In contrast, median urinary inorganic arsenic concentrations were greatest among participants from Hermosillo, Mexico (6.2 µg/L whereas a high of 2.0 µg/L was found among participants from Ajo, Arizona. Estimated arsenic intake from drinking water was associated with urinary total arsenic concentration (p < 0.001, urinary inorganic arsenic concentration (p < 0.001, and urinary sum of species (p < 0.001. Urinary arsenic concentrations increased between 7% and 12% for each one percent increase in arsenic consumed from drinking water. Variability in arsenic intake from beverages and urinary arsenic output yielded counter intuitive results. Estimated intake of arsenic from all beverages was greatest among Arizonans yet participants in Mexico had higher urinary total and inorganic arsenic concentrations. Other contributors to urinary arsenic concentrations should be evaluated.

Arsenic control during aquifer storage recovery cycle tests in the Floridan Aquifer.

Science.gov (United States)

Mirecki, June E; Bennett, Michael W; López-Baláez, Marie C

2013-01-01

Implementation of aquifer storage recovery (ASR) for water resource management in Florida is impeded by arsenic mobilization. Arsenic, released by pyrite oxidation during the recharge phase, sometimes results in groundwater concentrations that exceed the 10 µg/L criterion defined in the Safe Drinking Water Act. ASR was proposed as a major storage component for the Comprehensive Everglades Restoration Plan (CERP), in which excess surface water is stored during the wet season, and then distributed during the dry season for ecosystem restoration. To evaluate ASR system performance for CERP goals, three cycle tests were conducted, with extensive water-quality monitoring in the Upper Floridan Aquifer (UFA) at the Kissimmee River ASR (KRASR) pilot system. During each cycle test, redox evolution from sub-oxic to sulfate-reducing conditions occurs in the UFA storage zone, as indicated by decreasing Fe(2+) /H2 S mass ratios. Arsenic, released by pyrite oxidation during recharge, is sequestered during storage and recovery by co-precipitation with iron sulfide. Mineral saturation indices indicate that amorphous iron oxide (a sorption surface for arsenic) is stable only during oxic and sub-oxic conditions of the recharge phase, but iron sulfide (which co-precipitates arsenic) is stable during the sulfate-reducing conditions of the storage and recovery phases. Resultant arsenic concentrations in recovered water are below the 10 µg/L regulatory criterion during cycle tests 2 and 3. The arsenic sequestration process is appropriate for other ASR systems that recharge treated surface water into a sulfate-reducing aquifer. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

A new metabolic pathway of arsenite: arsenic-glutathione complexes are substrates for human arsenic methyltransferase Cyt19

Energy Technology Data Exchange (ETDEWEB)

Hayakawa, Toru [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan); Chiba University, Faculty of Pharmaceutical Sciences, Chiba (Japan); Kobayashi, Yayoi; Cui, Xing; Hirano, Seishiro [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan)

2005-04-01

The metabolism of arsenic is generally accepted to proceed by repetitive reduction and oxidative methylation; the latter is mediated by arsenic methyltransferase (Cyt19). In human urine, the major metabolites of inorganic arsenicals such as arsenite (iAs{sup III}) and arsenate (iAs{sup V}) are monomethylarsonic acid (MMA{sup V}) and dimethylarsinic acid (DMA{sup V}). On the other hand, in rat bile, the major metabolites of iAs{sup III} have been reported to be arsenic-glutathione (As-GSH) complexes. In the present study we investigate whether these As-GSH complexes are substrates for arsenic methyltransferase by using human recombinant Cyt19. Analyses by high-performance liquid chromatography-inductively coupled plasma mass spectrometry suggested that arsenic triglutathione (ATG) was generated nonenzymatically from iAs{sup III} when GSH was present at concentrations 2 mM or higher. Human recombinant Cyt19 catalyzed transfer of a methyl group from S-adenosyl-l-methionine to arsenic and produced monomethyl and dimethyl arsenicals. The methylation of arsenic was catalyzed by Cyt19 only when ATG was present in the reaction mixture. Moreover, monomethylarsonic diglutathione (MADG) was a substrate of Cyt19 for further methylation to dimethylarsinic glutathione (DMAG). On the other hand, monomethylarsonous acid (MMA{sup III}), a hydrolysis product of MADG, was not methylated to dimethyl arsenical by Cyt19. These results suggest that As-GSH complexes such as ATG and MADG were converted by Cyt19 to MADG and DMAG, respectively. Both MADG and DMAG were unstable in solution when the GSH concentration was lower than 1 mM, and were hydrolyzed and oxidized to MMA{sup V} and DMA{sup V}, respectively. Metabolism of iAs{sup III} to methylated arsenicals by Cyt19 was via ATG and MADG rather than by oxidative methylation of iAs{sup III} and MMA{sup III}. (orig.)

Phytoremediation of arsenic in submerged soil by wetland plants.

Science.gov (United States)

Jomjun, Nateewattana; Siripen, Trichaiyaporn; Maliwan, Saeouy; Jintapat, Nateewattana; Prasak, Thavornyutikarn; Somporn, Choonluchanon; Petch, Pengchai

2011-01-01

Wetland aquatic plants including Canna glauca L., Colocasia esculenta L. Schott, Cyperus papyrus L. and Typha angustifolia L. were used in the phytoremediation of submerged soil polluted by arsenic (As). Cyperus papyrus L. was noticed as the largest biomass producer which has arsenic accumulation capacity of 130-172 mg As/kg plant. In terms of arsenic removal rate, however, Colocasia esculenta L. was recognized as the largest and fastest arsenic remover in this study. Its arsenic removal rate was 68 mg As/m2/day while those rates of Canna glauca L., Cyperus papyrus L. and Typha angustifolia L. were 61 mg As/m2/day, 56 mg As/m2/day, and 56 mg As/m2/day, respectively. Although the 4 aquatic plants were inferior in arsenic accumulation, their high arsenic removal rates were observed. Phytostabilization should be probable for the application of these plants.

Dissolution of arsenic minerals mediated by dissimilatory arsenate reducing bacteria: estimation of the physiological potential for arsenic mobilization.

Science.gov (United States)

Lukasz, Drewniak; Liwia, Rajpert; Aleksandra, Mantur; Aleksandra, Sklodowska

2014-01-01

The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V) reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i) produced siderophores that promote dissolution of minerals, (ii) were resistant to dissolved arsenic compounds, (iii) were able to use the dissolved arsenates as the terminal electron acceptor, and (iii) were able to use copper minerals containing arsenic minerals (e.g., enargite) as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings) under reductive conditions by dissimilatory arsenate reducers in indirect processes.

Dissolution of Arsenic Minerals Mediated by Dissimilatory Arsenate Reducing Bacteria: Estimation of the Physiological Potential for Arsenic Mobilization

Directory of Open Access Journals (Sweden)

Drewniak Lukasz

2014-01-01

Full Text Available The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i produced siderophores that promote dissolution of minerals, (ii were resistant to dissolved arsenic compounds, (iii were able to use the dissolved arsenates as the terminal electron acceptor, and (iii were able to use copper minerals containing arsenic minerals (e.g., enargite as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings under reductive conditions by dissimilatory arsenate reducers in indirect processes.

Isolation of arsenic-tolerant bacteria from arsenic-contaminated soil

Directory of Open Access Journals (Sweden)

Vorasan Sobhon*

2008-04-01

Full Text Available The disposal of toxic heavy metals such as arsenic posed high risk to the environment. Arsenite [As(III], a reduced form of arsenic, is more toxic and mobile than arsenate [As(V]. The aim of this work was to isolate arsenic-tolerant bacteria from contaminated soil collected in Ronphibun District, Nakorn Srithammarat Province, followed by screening these bacteria for their ability to adsorb arsenite. Twenty-four bacterial isolates were obtained from samples cultivated in basal salts medium plus 0.1% yeast extract and up to 40 mM sodium-arsenite at 30oC under aerobic condition. From these, isolates B-2, B-3, B-4, B-21, B-25 and B-27 produced extracellular polymeric-like substances into the culture medium, which may potentially be used in the bioremediation of arsenic and other contaminants. All isolates displayed arsenite adsorbing activities in the ranges of 36.87-96.93% adsorption from initial concentration of 40 mM sodium-arsenite, without any arsenic transforming activity. Five isolates with the highest arsenite adsorbing capacity include B-4, B-7, B-8, B-10 and B-13 which adsorbed 80.90, 86.72, 87.08, 84.36 and 96.93% arsenite, respectively. Identification of their 16S rDNA sequences showed B -7, B-8, and B-10 to have 97%, 99% and 97% identities to Microbacterium oxydans, Achromobacter sp. and Ochrobactrum anthropi, respectively. Isolates B-4 and B-13, which did not show sequence similarity to any bacterial species, may be assigned based on their morphological and biochemical characteristics to the genus Streptococcus and Xanthomonas, respectively. Thus, both isolates B-4 and B-13 appear to be novel arsenite adsorbing bacteria within these genuses.

Rapid biotransformation of arsenic by a model protozoan Tetrahymena thermophila

Energy Technology Data Exchange (ETDEWEB)

Yin Xixiang [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhang Yongyu; Yang Jun [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Zhu Yongguan, E-mail: ygzhu@rcees.ac.cn [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

2011-04-15

Arsenic biomethylation and biovolatilization are thought to be two important metabolic pathways in aquatic and soil environments. Tetrahymena thermophila is a genus of free-living ciliated protozoan that is widely distributed in freshwater environments around the world. In this study, we studied arsenic accumulation, speciation, efflux, methylation and volatilization in this unicellular eukaryote exposed to various concentrations of arsenate. Our results show that T. thermophila accumulated 187 mg.kg{sup -1} dry weight of arsenic when exposed to 40 {mu}M for 48 h, with MMAs(V) (monomethylarsenate) and DMAs(V) (dimethylarsenate) as the dominant species, accounting for 66% of the total arsenic. Meanwhile, arsenate, arsenite, MMAs(V) and DMAs(V) were detected in the culture medium; the last three were released by the cells. The production of volatile arsenic increased with increasing external As(V) concentrations and exposure time. To our knowledge, this is the first study on arsenic metabolism, particularly biomethylation and biovolatilization, in protozoa. - Tetrahymena thermophila can rapidly methylate arsenic, and produce volatile arsenicals.

Phytoextraction by arsenic hyperaccumulator Pteris vittata L. from six arsenic-contaminated soils: Repeated harvests and arsenic redistribution

Energy Technology Data Exchange (ETDEWEB)

Gonzaga, Maria I.S.; Santos, Jorge A.G. [Department of Soil Chemistry, Universidade Federal da Bahia, Cruz das Almas, 44380000 (Brazil); Ma, Lena Q. [Soil and Water Science Department, University of Florida, 2169 McCarty Hall, Gainesville, FL 32611-0290 (United States)], E-mail: lqma@ifas.ufl.edu

2008-07-15

This greenhouse experiment evaluated arsenic removal by Pteris vittata and its effects on arsenic redistribution in soils. P. vittata grew in six arsenic-contaminated soils and its fronds were harvested and analyzed for arsenic in October, 2003, April, 2004, and October, 2004. The soil arsenic was separated into five fractions via sequential extraction. The ferns grew well and took up arsenic from all soils. Fern biomass ranged from 24.8 to 33.5 g plant{sup -1} after 4 months of growth but was reduced in the subsequent harvests. The frond arsenic concentrations ranged from 66 to 6,151 mg kg{sup -1}, 110 to 3,056 mg kg{sup -1}, and 162 to 2,139 mg kg{sup -1} from the first, second and third harvest, respectively. P. vittata reduced soil arsenic by 6.4-13% after three harvests. Arsenic in the soils was primarily associated with amorphous hydrous oxides (40-59%), which contributed the most to arsenic taken up by P. vittata (45-72%). It is possible to use P. vittata to remediate arsenic-contaminated soils by repeatedly harvesting its fronds. - Pteris vittata was effective in continuously removing arsenic from contaminated soils after three repeated harvests.

Transplacental arsenic carcinogenesis in mice

International Nuclear Information System (INIS)

Waalkes, Michael P.; Liu, Jie; Diwan, Bhalchandra A.

2007-01-01

Our work has focused on the carcinogenic effects of in utero arsenic exposure in mice. Our data show that a short period of maternal exposure to inorganic arsenic in the drinking water is an effective, multi-tissue carcinogen in the adult offspring. These studies have been reproduced in three temporally separate studies using two different mouse strains. In these studies pregnant mice were treated with drinking water containing sodium arsenite at up to 85 ppm arsenic from days 8 to 18 of gestation, and the offspring were observed for up to 2 years. The doses used in all these studies were well tolerated by both the dam and offspring. In C3H mice, two separate studies show male offspring exposed to arsenic in utero developed liver carcinoma and adrenal cortical adenoma in a dose-related fashion during adulthood. Prenatally exposed female C3H offspring show dose-related increases in ovarian tumors and lung carcinoma and in proliferative lesions (tumors plus preneoplastic hyperplasia) of the uterus and oviduct. In addition, prenatal arsenic plus postnatal exposure to the tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate (TPA) in C3H mice produces excess lung tumors in both sexes and liver tumors in females. Male CD1 mice treated with arsenic in utero develop tumors of the liver and adrenal and renal hyperplasia while females develop tumors of urogenital system, ovary, uterus and adrenal and hyperplasia of the oviduct. Additional postnatal treatment with diethylstilbestrol or tamoxifen after prenatal arsenic in CD1 mice induces urinary bladder transitional cell proliferative lesions, including carcinoma and papilloma, and enhances the carcinogenic response in the liver of both sexes. Overall this model has provided convincing evidence that arsenic is a transplacental carcinogen in mice with the ability to target tissues of potential human relevance, such as the urinary bladder, lung and liver. Transplacental carcinogenesis clearly occurs with other agents in humans

Arsenic pollution sources.

Science.gov (United States)

Garelick, Hemda; Jones, Huw; Dybowska, Agnieszka; Valsami-Jones, Eugenia

2008-01-01

Arsenic is a widely dispersed element in the Earth's crust and exists at an average concentration of approximately 5 mg/kg. There are many possible routes of human exposure to arsenic from both natural and anthropogenic sources. Arsenic occurs as a constituent in more than 200 minerals, although it primarily exists as arsenopyrite and as a constituent in several other sulfide minerals. The introduction of arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Arsenic-containing bedrock formations of this sort are known in Bangladesh, West Bengal (India), and regions of China, and many cases of endemic contamination by arsenic with serious consequences to human health are known from these areas. Significant natural contamination of surface waters and soil can arise when arsenic-rich geothermal fluids come into contact with surface waters. When humans are implicated in causing or exacerbating arsenic pollution, the cause can almost always be traced to mining or mining-related activities. Arsenic exists in many oxidation states, with arsenic (III) and (V) being the most common forms. Similar to many metalloids, the prevalence of particular species of arsenic depends greatly on the pH and redox conditions of the matrix in which it exists. Speciation is also important in determining the toxicity of arsenic. Arsenic minerals exist in the environment principally as sulfides, oxides, and phosphates. In igneous rocks, only those of volcanic origin are implicated in high aqueous arsenic concentrations. Sedimentary rocks tend not to bear high arsenic loads, and common matrices such as sands and sandstones contain lower concentrations owing to the dominance of quartz and feldspars. Groundwater contamination by arsenic arises from sources of arsenopyrite, base metal sulfides, realgar and orpiment, arsenic-rich pyrite, and iron oxyhydroxide. Mechanisms by which arsenic is released from minerals are varied and are accounted for by

Oxidation and detoxification of trivalent arsenic species

International Nuclear Information System (INIS)

Aposhian, H. Vasken; Zakharyan, Robert A.; Avram, Mihaela D.; Kopplin, Michael J.; Wollenberg, Michael L.

2003-01-01

Arsenic compounds with a +3 oxidation state are more toxic than analogous compounds with a +5 oxidation state, for example, arsenite versus arsenate, monomethylarsonous acid (MMA III ) versus monomethylarsonic acid (MMA V ), and dimethylarsinous acid (DMA III ) versus dimethylarsinic acid (DMA V ). It is no longer believed that the methylation of arsenite is the beginning of a methylation-mediated detoxication pathway. The oxidation of these +3 compounds to their less toxic +5 analogs by hydrogen peroxide needs investigation and consideration as a potential mechanism for detoxification. Xanthine oxidase uses oxygen to oxidize hypoxanthine to xanthine to uric acid. Hydrogen peroxide and reactive oxygen are also products. The oxidation of +3 arsenicals by the hydrogen peroxide produced in the xanthine oxidase reaction was blocked by catalase or allopurinol but not by scavengers of the hydroxy radical, e.g., mannitol or potassium iodide. Melatonin, the singlet oxygen radical scavenger, did not inhibit the oxidation. The production of H 2 O 2 by xanthine oxidase may be an important route for decreasing the toxicity of trivalent arsenic species by oxidizing them to their less toxic pentavalent analogs. In addition, there are many other reactions that produce hydrogen peroxide in the cell. Although chemists have used hydrogen peroxide for the oxidation of arsenite to arsenate to purify water, we are not aware of any published account of its potential importance in the detoxification of trivalent arsenicals in biological systems. At present, this oxidation of the +3 oxidation state arsenicals is based on evidence from in vitro experiments. In vivo experiments are needed to substantiate the role and importance of H 2 O 2 in arsenic detoxication in mammals

Urinary arsenic species, toenail arsenic, and arsenic intake estimates in a Michigan population with low levels of arsenic in drinking water.

Science.gov (United States)

Rivera-Núñez, Zorimar; Meliker, Jaymie R; Meeker, John D; Slotnick, Melissa J; Nriagu, Jerome O

2012-01-01

The large disparity between arsenic concentrations in drinking water and urine remains unexplained. This study aims to evaluate predictors of urinary arsenic in a population exposed to low concentrations (≤50 μg/l) of arsenic in drinking water. Urine and drinking water samples were collected from a subsample (n=343) of a population enrolled in a bladder cancer case-control study in southeastern Michigan. Total arsenic in water and arsenic species in urine were determined using ICP-MS: arsenobetaine (AsB), arsenite (As[III]), arsenate (As[V]), methylarsenic acid (MMA[V]), and dimethylarsenic acid (DMA[V]). The sum of As[III], As[V], MMA[V], and DMA[V] was denoted as SumAs. Dietary information was obtained through a self-reported food intake questionnaire. Log(10)-transformed drinking water arsenic concentration at home was a significant (Pwater were removed and further improved when analyses were applied to individuals who consumed amounts of home drinking water above the median volume (R(2)=0.40, Pwater was 0.42. Results show that arsenic exposure from drinking water consumption is an important determinant of urinary arsenic concentrations, even in a population exposed to relatively low levels of arsenic in drinking water, and suggest that seafood intake may influence urinary DMA[V] concentrations.

Arsenic tolerance in Arabidopsis is mediated by two ABCC-type phytochelatin transporters

Science.gov (United States)

Song, Won-Yong; Park, Jiyoung; Mendoza-Cózatl, David G.; Suter-Grotemeyer, Marianne; Shim, Donghwan; Hörtensteiner, Stefan; Geisler, Markus; Weder, Barbara; Rea, Philip A.; Rentsch, Doris; Schroeder, Julian I.; Lee, Youngsook; Martinoia, Enrico

2010-01-01

Arsenic is an extremely toxic metalloid causing serious health problems. In Southeast Asia, aquifers providing drinking and agricultural water for tens of millions of people are contaminated with arsenic. To reduce nutritional arsenic intake through the consumption of contaminated plants, identification of the mechanisms for arsenic accumulation and detoxification in plants is a prerequisite. Phytochelatins (PCs) are glutathione-derived peptides that chelate heavy metals and metalloids such as arsenic, thereby functioning as the first step in their detoxification. Plant vacuoles act as final detoxification stores for heavy metals and arsenic. The essential PC–metal(loid) transporters that sequester toxic metal(loid)s in plant vacuoles have long been sought but remain unidentified in plants. Here we show that in the absence of two ABCC-type transporters, AtABCC1 and AtABCC2, Arabidopsis thaliana is extremely sensitive to arsenic and arsenic-based herbicides. Heterologous expression of these ABCC transporters in phytochelatin-producing Saccharomyces cerevisiae enhanced arsenic tolerance and accumulation. Furthermore, membrane vesicles isolated from these yeasts exhibited a pronounced arsenite [As(III)]–PC2 transport activity. Vacuoles isolated from atabcc1 atabcc2 double knockout plants exhibited a very low residual As(III)–PC2 transport activity, and interestingly, less PC was produced in mutant plants when exposed to arsenic. Overexpression of AtPCS1 and AtABCC1 resulted in plants exhibiting increased arsenic tolerance. Our findings demonstrate that AtABCC1 and AtABCC2 are the long-sought and major vacuolar PC transporters. Modulation of vacuolar PC transporters in other plants may allow engineering of plants suited either for phytoremediation or reduced accumulation of arsenic in edible organs. PMID:21078981

Trace metal distribution and mobility in drill cuttings and produced waters from Marcellus Shale gas extraction: Uranium, arsenic, barium

International Nuclear Information System (INIS)

Phan, Thai T.; Capo, Rosemary C.; Stewart, Brian W.; Graney, Joseph R.; Johnson, Jason D.; Sharma, Shikha; Toro, Jaime

2015-01-01

Highlights: • Distributions of U, As, and Ba in Marcellus Shale were determined. • As is primarily associated with sulfide minerals, Ba with exchange sites. • Most U is in the silicate minerals, but up to 20% is partitioned into carbonate. • Low [U] and [As] in produced water are consistent with reducing downhole conditions. • Proper waste management should account for potential mobilization of U and As. - Abstract: Development of unconventional shale gas wells can generate significant quantities of drilling waste, including trace metal-rich black shale from the lateral portion of the drillhole. We carried out sequential extractions on 15 samples of dry-drilled cuttings and core material from the gas-producing Middle Devonian Marcellus Shale and surrounding units to identify the host phases and evaluate the mobility of selected trace elements during cuttings disposal. Maximum whole rock concentrations of uranium (U), arsenic (As), and barium (Ba) were 47, 90, and 3333 mg kg −1 , respectively. Sequential chemical extractions suggest that although silicate minerals are the primary host for U, as much as 20% can be present in carbonate minerals. Up to 74% of the Ba in shale was extracted from exchangeable sites in the shale, while As is primarily associated with organic matter and sulfide minerals that could be mobilized by oxidation. For comparison, U and As concentrations were also measured in 43 produced water samples returned from Marcellus Shale gas wells. Low U concentrations in produced water (<0.084–3.26 μg L −1 ) are consistent with low-oxygen conditions in the wellbore, in which U would be in its reduced, immobile form. Arsenic was below detection in all produced water samples, which is also consistent with reducing conditions in the wellbore minimizing oxidation of As-bearing sulfide minerals. Geochemical modeling to determine mobility under surface storage and disposal conditions indicates that oxidation and/or dissolution of U

Roxarsone, inorganic arsenic, and other arsenic species in chicken: a U.S.-based market basket sample.

Science.gov (United States)

Nachman, Keeve E; Baron, Patrick A; Raber, Georg; Francesconi, Kevin A; Navas-Acien, Ana; Love, David C

2013-07-01

Inorganic arsenic (iAs) causes cancer and possibly other adverse health outcomes. Arsenic-based drugs are permitted in poultry production; however, the contribution of chicken consumption to iAs intake is unknown. We sought to characterize the arsenic species profile in chicken meat and estimate bladder and lung cancer risk associated with consuming chicken produced with arsenic-based drugs. Conventional, antibiotic-free, and organic chicken samples were collected from grocery stores in 10 U.S. metropolitan areas from December 2010 through June 2011. We tested 116 raw and 142 cooked chicken samples for total arsenic, and we determined arsenic species in 65 raw and 78 cooked samples that contained total arsenic at ≥ 10 µg/kg dry weight. The geometric mean (GM) of total arsenic in cooked chicken meat samples was 3.0 µg/kg (95% CI: 2.5, 3.6). Among the 78 cooked samples that were speciated, iAs concentrations were higher in conventional samples (GM = 1.8 µg/kg; 95% CI: 1.4, 2.3) than in antibiotic-free (GM = 0.7 µg/kg; 95% CI: 0.5, 1.0) or organic (GM = 0.6 µg/kg; 95% CI: 0.5, 0.8) samples. Roxarsone was detected in 20 of 40 conventional samples, 1 of 13 antibiotic-free samples, and none of the 25 organic samples. iAs concentrations in roxarsone-positive samples (GM = 2.3 µg/kg; 95% CI: 1.7, 3.1) were significantly higher than those in roxarsone-negative samples (GM = 0.8 µg/kg; 95% CI: 0.7, 1.0). Cooking increased iAs and decreased roxarsone concentrations. We estimated that consumers of conventional chicken would ingest an additional 0.11 µg/day iAs (in an 82-g serving) compared with consumers of organic chicken. Assuming lifetime exposure and a proposed cancer slope factor of 25.7 per milligram per kilogram of body weight per day, this increase in arsenic exposure could result in 3.7 additional lifetime bladder and lung cancer cases per 100,000 exposed persons. Conventional chicken meat had higher iAs concentrations than did conventional antibiotic

Arsenic biotransformation and volatilization in transgenic rice

Science.gov (United States)

Meng, Xiang-Yan; Qin, Jie; Wang, Li-Hong; Duan, Gui-Lan; Sun, Guo-Xin; Wu, Hui-Lan; Chu, Cheng-Cai; Ling, Hong-Qing; Rosen, Barry P.; Zhu, Yong-Guan

2011-01-01

Summary Biotransformation of arsenic includes oxidation, reduction, methylation and conversion to more complex organic arsenicals. Members of the class of arsenite [As(III)] S-adenosylmethyltransferase enzymes catalyze As(III) methylation to a variety of mono-, di- and trimethylated species, some of which are less toxic than As(III) itself. However, no methyltransferase gene has been identified in plants. Here, an arsM gene from the soil bacterium Rhodopseudomonas palustris was expressed in Japonica rice (Oryza sativa L.) cultivar Nipponbare, and the transgenic rice produced methylated arsenic species, which were measured by inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Both monomethylarsenate [MAs(V)] and dimethylarsenate [DMAs(V)] were detected in the root and shoot of transgenic rice. After 12-d exposure to As(III), the transgenic rice gave off 10-fold more volatile arsenicals. The present study demonstrates that expression of an arsM gene in rice induces arsenic methylation and volatilization, providing a potential stratagem for phytoremediation theoretically. PMID:21517874

Characterizations of arsenic-doped zinc oxide films produced by atmospheric metal-organic chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

Weng, Li-Wei, E-mail: onlyway54@hotmail.com [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Uen, Wu-Yih, E-mail: uenwuyih@ms37.hinet.net [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Lan, Shan-Ming; Liao, Sen-Mao [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Yang, Tsun-Neng; Wu, Chih-Hung; Hong, Hwe-Fen; Ma, Wei-Yang [Institute of Nuclear Energy Research, P.O. Box 3-11, Lungtan 32500, Taiwan (China); Shen, Chin-Chang [Chemical Engineering Division, Institute of Nuclear Energy Research, Longtan Township, Taoyuan 32546, Taiwan (China)

2013-07-15

p-type ZnO films were prepared by atmospheric metal-organic chemical vapor deposition technique using arsine (AsH{sub 3}) as the doping source. The electrical and optical properties of arsenic-doped ZnO (ZnO:As) films fabricated at 450–600 °C with various AsH{sub 3} flow rates ranging from 8 to 21.34 μmol/min were analyzed and compared. Hall measurements indicate that stable p-type ZnO films with hole concentrations varying from 7.2 × 10{sup 15} to 5.8 × 10{sup 18} cm{sup −3} could be obtained. Besides, low temperature (17 K) photoluminescence spectra of all ZnO:As films also demonstrate the dominance of the line related to the neutral acceptor-bound exciton. Moreover, the elemental identity and chemical bonding information for ZnO:As films were examined by X-ray photoelectron spectroscopy. Based on the results obtained, the effects of doping conditions on the mechanism responsible for the p-type conduction were studied. Conclusively, a simple technique to fabricate good-quality p-type ZnO films has been recognized in this work. Depositing the film at 550 °C with an AsH{sub 3} flow rate of 13.72 μmol/min is appropriate for producing hole concentrations on the order of 10{sup 17} cm{sup −3} for it. Ultimately, by increasing the AsH{sub 3} flow rate to 21.34 μmol/min for doping and depositing the film at 600 °C, ZnO:As films with a hole concentration over 5 × 10{sup 18} cm{sup −3} together with a mobility of 1.93 cm{sup 2}V{sup −1} s{sup −1} and a resistivity of 0.494 ohm-cm can be achieved.

A MODEL FOR PRODUCING STABLE, BROADBAND TERAHERTZ COHERENT SYNCHROTRON RADIATION IN STORAGE RINGS

International Nuclear Information System (INIS)

Sannibale, Fernando; Byrd, John M.; Loftsdottir, Agusta; Martin, MichaelC.; Venturini, Marco

2003-01-01

We present a model for producing stable broadband coherent synchrotron radiation (CSR) in the terahertz frequency region in an electron storage ring. The model includes distortion of bunch shape from the synchrotron radiation (SR), enhancing higher frequency coherent emission and limits to stable emission due to a microbunching instability excited by the SR. We use this model to optimize the performance of a source for CSR emission

Reaction Mechanism and Distribution Behavior of Arsenic in the Bottom Blown Copper Smelting Process

Directory of Open Access Journals (Sweden)

Qinmeng Wang

2017-08-01

Full Text Available The control of arsenic, a toxic and carcinogenic element, is an important issue for all copper smelters. In this work, the reaction mechanism and distribution behavior of arsenic in the bottom blown copper smelting process (SKS process were investigated and compared to the flash smelting process. There are obvious differences of arsenic distribution in the SKS process and flash process, resulting from the differences of oxygen potentials, volatilizations, smelting temperatures, reaction intensities, and mass transfer processes. Under stable production conditions, the distributions of arsenic among matte, slag, and gas phases are 6%, 12%, and 82%, respectively. Less arsenic is reported in the gas phase with the flash process than with the SKS process. The main arsenic species in gas phase are AsS (g, AsO (g, and As2 (g. Arsenic exists in the slag predominantly as As2O3 (l, and in matte as As (l. High matte grade is harmful to the elimination of arsenic to gas. The changing of Fe/SiO2 has slight effects on the distributions of arsenic. In order to enhance the removal of arsenic from the SKS smelting system to the gas phase, low oxygen concentration, low ratios of oxygen/ore, and low matte grade should be chosen. In the SKS smelting process, no dust is recycled, and almost all dust is collected and further treated to eliminate arsenic and recover valuable metals by other process streams.

THE ROLE OF FLAVONOIDS IN MODULATION OF THE METABOLISM OF ARSENIC

Science.gov (United States)

The biotransformation of inorganic arsenic (iAs) in humans produces trivalent and pentavalent methylated species. The pattern and extent of iAs conversion is critical for the overall toxicity and adverse health effects associated with arsenic exposure. Our previous work showed a ...

Iron coated pottery granules for arsenic removal from drinking water.

Science.gov (United States)

Dong, Liangjie; Zinin, Pavel V; Cowen, James P; Ming, Li Chung

2009-09-15

A new media, iron coated pottery granules (ICPG) has been developed for As removal from drinking water. ICPG is a solid phase media that produces a stable Fe-Si surface complex for arsenic adsorption. Scanning electron microscopy (SEM) was used to document the physical attributes (grain size, pore size and distribution, surface roughness) of the ICPG media. Several advantages of the ICPG media such as (a) its granular structure, (b) its ability to absorb As via the F(0) coating on the granules' surface; (c) the inexpensive preparation process for the media from clay material make ICPG media a highly effective media for removing arsenic at normal pH. A column filtration test demonstrated that within the stability region (flow rate lower than 15L/h, EBCT >3 min), the concentration of As in the influent was always lower than 50 microg/L. The 2-week system ability test showed that the media consistently removed arsenic from test water to below the 5 microg/L level. The average removal efficiencies for total arsenic, As(III), and As(V) for a 2-week test period were 98%, 97%, and 99%, respectively, at an average flow rate of 4.1L/h and normal pH. Measurements of the Freundlich and Langmuir isotherms at normal pH show that the Freundlich constants of the ICPG are very close to those of ferric hydroxide, nanoscale zero-valent iron and much higher than those of nanocrystalline titanium dioxide. The parameter 1/n is smaller than 0.55 indicating a favorable adsorption process [K. Hristovski, A. Baumgardner, P. Westerhoff, Selecting metal oxide nanomaterials for arsenic removal in fixed bed columns: from nanopowders to aggregated nanoparticle media, J. Hazard. Mater. 147 (2007) 265-274]. The maximum adsorption capacity (q(e)) of the ICPG from the Langmuir isotherm is very close to that of nanoscale zero-valent indicating that zero-valent iron is involved in the process of the As removal from the water. The results of the toxicity characteristic leaching procedure (TCLP

Iron coated pottery granules for arsenic removal from drinking water

International Nuclear Information System (INIS)

Dong Liangjie; Zinin, Pavel V.; Cowen, James P.; Ming, Li Chung

2009-01-01

A new media, iron coated pottery granules (ICPG) has been developed for As removal from drinking water. ICPG is a solid phase media that produces a stable Fe-Si surface complex for arsenic adsorption. Scanning electron microscopy (SEM) was used to document the physical attributes (grain size, pore size and distribution, surface roughness) of the ICPG media. Several advantages of the ICPG media such as (a) its granular structure, (b) its ability to absorb As via the F(0) coating on the granules' surface; (c) the inexpensive preparation process for the media from clay material make ICPG media a highly effective media for removing arsenic at normal pH. A column filtration test demonstrated that within the stability region (flow rate lower than 15 L/h, EBCT >3 min), the concentration of As in the influent was always lower than 50 μg/L. The 2-week system ability test showed that the media consistently removed arsenic from test water to below the 5 μg/L level. The average removal efficiencies for total arsenic, As(III), and As(V) for a 2-week test period were 98%, 97%, and 99%, respectively, at an average flow rate of 4.1 L/h and normal pH. Measurements of the Freundlich and Langmuir isotherms at normal pH show that the Freundlich constants of the ICPG are very close to those of ferric hydroxide, nanoscale zero-valent iron and much higher than those of nanocrystalline titanium dioxide. The parameter 1/n is smaller than 0.55 indicating a favorable adsorption process [K. Hristovski, A. Baumgardner, P. Westerhoff, Selecting metal oxide nanomaterials for arsenic removal in fixed bed columns: from nanopowders to aggregated nanoparticle media, J. Hazard. Mater. 147 (2007) 265-274]. The maximum adsorption capacity (q e ) of the ICPG from the Langmuir isotherm is very close to that of nanoscale zero-valent indicating that zero-valent iron is involved in the process of the As removal from the water. The results of the toxicity characteristic leaching procedure (TCLP) analysis

Evaluation of the sustainability of deep groundwater as an arsenic-safe resource in the Bengal Basin

OpenAIRE

Michael, Holly A.; Voss, Clifford I.

2008-01-01

Tens of millions of people in the Bengal Basin region of Bangladesh and India drink groundwater containing unsafe concentrations of arsenic. This high-arsenic groundwater is produced from shallow (150 m where groundwater arsenic concentrations are nearly uniformly low, and many more wells are needed, however, the sustainability of deep, arsenic-safe groundwater has not been previously assessed. Deeper pumping could induce downward migration of dissolved arsenic, permanently destroying the dee...

Phytoremediation of arsenic contaminated soil by arsenic accumulators: a three year study.

Science.gov (United States)

Raj, Anshita; Singh, Nandita

2015-03-01

To investigate whether phytoremediation can remove arsenic from the contaminated area, a study was conducted for three consecutive years to determine the efficiency of Pteris vittata, Adiantum capillus veneris, Christella dentata and Phragmites karka, on arsenic removal from the arsenic contaminated soil. Arsenic concentrations in the soil samples were analysed after harvesting in 2009, 2010 and 2011 at an interval of 6 months. Frond arsenic concentrations were also estimated in all the successive harvests. Fronds resulted in the greatest amount of arsenic removal. Root arsenic concentrations were analysed in the last harvest. Approximately 70 % of arsenic was removed by P. vittata which was recorded as the highest among the four plant species. However, 60 % of arsenic was removed by A. capillus veneris, 55.1 % by C. dentata and 56.1 % by P. karka of arsenic was removed from the contaminated soil in 3 years.

Predicting arsenic concentrations in groundwater of San Luis Valley, Colorado: implications for individual-level lifetime exposure assessment.

Science.gov (United States)

James, Katherine A; Meliker, Jaymie R; Buttenfield, Barbara E; Byers, Tim; Zerbe, Gary O; Hokanson, John E; Marshall, Julie A

2014-08-01

Consumption of inorganic arsenic in drinking water at high levels has been associated with chronic diseases. Risk is less clear at lower levels of arsenic, in part due to difficulties in estimating exposure. Herein we characterize spatial and temporal variability of arsenic concentrations and develop models for predicting aquifer arsenic concentrations in the San Luis Valley, Colorado, an area of moderately elevated arsenic in groundwater. This study included historical water samples with total arsenic concentrations from 595 unique well locations. A longitudinal analysis established temporal stability in arsenic levels in individual wells. The mean arsenic levels for a random sample of 535 wells were incorporated into five kriging models to predict groundwater arsenic concentrations at any point in time. A separate validation dataset (n = 60 wells) was used to identify the model with strongest predictability. Findings indicate that arsenic concentrations are temporally stable (r = 0.88; 95 % CI 0.83-0.92 for samples collected from the same well 15-25 years apart) and the spatial model created using ordinary kriging best predicted arsenic concentrations (ρ = 0.72 between predicted and observed validation data). These findings illustrate the value of geostatistical modeling of arsenic and suggest the San Luis Valley is a good region for conducting epidemiologic studies of groundwater metals because of the ability to accurately predict variation in groundwater arsenic concentrations.

Tracking natural and anthropogenic origins of dissolved arsenic during surface and groundwater interaction in a post-closure mining context: Isotopic constraints.

Science.gov (United States)

Khaska, Mahmoud; Le Gal La Salle, Corinne; Verdoux, Patrick; Boutin, René

2015-01-01

Arsenic contamination of stream waters and groundwater is a real issue in Au-As mine environments. At the Salsigne Au-As mine, southern France, arsenic contamination persists after closure and remediation of the site. In this study, natural and anthropogenic arsenic inputs in surface water and groundwater are identified based on (87)Sr/(86)Sr, and δ(18)O and δ(2)H isotopic composition of water. In the wet season, downstream of the remediated zone, the arsenic contents in stream water and alluvial aquifer groundwater are high, with values in the order of 36 μg/L and 40 μg/L respectively, while upstream natural background average concentrations are around 4 μg/L. Locally down-gradient of the reclaimed area, arsenic concentrations in stream water showed 2 peaks, one during an important rainy event (101 mm) in the wet season in May, and a longer one over the dry period, reaching 120 and 110 μg/L respectively. The temporal variations in arsenic content in stream water can be explained i) during the dry season, by release of arsenic stored in the alluvial sediments through increased contribution from base flow and decreased stream flow and ii) during major rainy events, by mobilization of arsenic associated with important surface runoff. The (87)Sr/(86)Sr ratios associated with increasing arsenic content in stream waters downstream of the reclaimed area are significantly lower than that of the natural Sr inherited from Variscan formations. These low (87)Sr/(86)Sr ratios are likely to be associated with the decontaminating water treatment processes, used in the past and still at present, where CaO, produced from marine limestone and therefore showing a low (87)Sr/(86)Sr ratios, is used to precipitate Ca3(AsO4)2. The low Sr isotope signatures will then impact on the Sr isotope ratio of (1) the Ca-arsenate stored in tailing dams, (2) effluent currently produced by water treatment process and (3) groundwater draining from the overall site. Furthermore, Δ(2)H shows

Arsenic (+3 oxidation state) methyltransferase and the inorganic arsenic methylation phenotype

International Nuclear Information System (INIS)

Li Jiaxin; Waters, Stephen B.; Drobna, Zuzana; Devesa, Vicenta; Styblo, Miroslav; Thomas, David J.

2005-01-01

Inorganic arsenic is enzymatically methylated; hence, its ingestion results in exposure to the parent compound and various methylated arsenicals. Both experimental and epidemiological evidences suggest that some of the adverse health effects associated with chronic exposure to inorganic arsenic may be mediated by these methylated metabolites. If i As methylation is an activation process, then the phenotype for inorganic arsenic methylation may determine risk associated with exposure to this metalloid. We examined inorganic arsenic methylation phenotypes and arsenic (+3 oxidation state) methyltransferase genotypes in four species: three that methylate inorganic arsenic (human (Homo sapiens), rat (Rattus norwegicus), and mouse (Mus musculus)) and one that does not methylate inorganic arsenic (chimpanzee, Pan troglodytes). The predicted protein products from arsenic (+3 oxidation state) methyltransferase are similar in size for rat (369 amino acid residues), mouse (376 residues), and human (375 residues). By comparison, a 275-nucleotide deletion beginning at nucleotide 612 in the chimpanzee gene sequence causes a frameshift that leads to a nonsense mutation for a premature stop codon after amino acid 205. The null phenotype for inorganic arsenic methylation in the chimpanzee is likely due to the deletion in the gene for arsenic (+3 oxidation state) methyltransferase that yields an inactive truncated protein. This lineage-specific loss of function caused by the deletion event must have occurred in the Pan lineage after Homo-Pan divergence about 5 million years ago

Blood Pressure Associated with Arsenic Methylation and Arsenic Metabolism Caused by Chronic Exposure to Arsenic in Tube Well Water.

Science.gov (United States)

Wei, Bing Gan; Ye, Bi Xiong; Yu, Jiang Ping; Yang, Lin Sheng; Li, Hai Rong; Xia, Ya Juan; Wu, Ke Gong

2017-05-01

The effects of arsenic exposure from drinking water, arsenic metabolism, and arsenic methylation on blood pressure (BP) were observed in this study. The BP and arsenic species of 560 participants were determined. Logistic regression analysis was applied to estimate the odds ratios of BP associated with arsenic metabolites and arsenic methylation capability. BP was positively associated with cumulative arsenic exposure (CAE). Subjects with abnormal diastolic blood pressure (DBP), systolic blood pressure (SBP), and pulse pressure (PP) usually had higher urinary iAs (inorganic arsenic), MMA (monomethylated arsenic), DMA (dimethylated arsenic), and TAs (total arsenic) than subjects with normal DBP, SBP, and PP. The iAs%, MMA%, and DMA% differed slightly between subjects with abnormal BP and those with normal BP. The PMI and SMI were slightly higher in subjects with abnormal PP than in those with normal PP. Our findings suggest that higher CAE may elevate BP. Males may have a higher risk of abnormal DBP, whereas females have a higher risk of abnormal SBP and PP. Higher urinary iAs may increase the risk of abnormal BP. Lower PMI may elevate the BP. However, higher SMI may increase the DBP and SBP, and lower SMI may elevate the PP. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Association of oxidative stress with arsenic methylation in chronic arsenic-exposed children and adults

International Nuclear Information System (INIS)

Xu Yuanyuan; Wang Yi; Zheng Quanmei; Li Xin; Li Bing; Jin Yaping; Sun Xiance; Sun Guifan

2008-01-01

Though oxidative stress is recognized as an important pathogenic mechanism of arsenic, and arsenic methylation capacity is suggested to be highly involved in arsenic-related diseases, the association of arsenic methylation capacity with arsenic-induced oxidative stress remains unclear. To explore oxidative stress and its association with arsenic methylation, cross-sectional studies were conducted among 208 high and 59 low arsenic-exposed subjects. Levels of urinary arsenic species [inorganic arsenic (iAs), monomethylated arsenic (MMA) and dimethylated arsenic (DMA)] were determined by hydride generation atomic absorption spectrometry. Proportions of urinary arsenic species, the first methylation ratio (FMR) and the secondary methylation ratio (SMR) were used as indicators for arsenic methylation capacity. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations were analyzed by enzyme-linked immunosorbent assay kits. Reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity in whole blood were determined to reflect anti-oxidative status. The high arsenic-exposed children and adults were significantly increased in urinary 8-OHdG concentrations but decreased in blood GSH levels compared with the low exposed children and adults. In multiple linear regression models, blood GSH levels and urinary 8-OHdG concentrations of arsenic-exposed children and adults showed strong associations with the levels of urinary arsenic species. Arsenic-exposed subjects in the lower and the upper quartiles of proportions of urinary arsenic species, FMR or SMR were significantly different in urinary 8-OHdG, blood GSH and SOD. The associations of arsenic methylation capacity with 8-OHdG, GSH and SOD were also observed in multivariate regression analyses. These results may provide linkage between arsenic methylation capacity and oxidative stress in humans and suggest that adverse health effects induced by arsenic are related to arsenic methylation through oxidative stress

Stable producer cell lines for adeno-associated virus (AAV) assembly.

Science.gov (United States)

Chadeuf, Gilliane; Salvetti, Anna

2010-10-01

Stable producer cell lines containing both the rep and cap genes and recombinant adeno-associated virus (rAAV) vectors can be infected with a helper virus to provide reliable and efficient production of rAAV stocks. However, the development of these cell lines is time-consuming. The procedure described here is therefore recommended only for studies requiring the production of high amounts of rAAV, such as preclinical studies performed in large animals.

Naturally occurring arsenic in the groundwater at the Kansas City Plant

Energy Technology Data Exchange (ETDEWEB)

Korte, N.E.

1990-12-01

This report describes an investigation concerning the presence of arsenic in concentrations exceeding 0.4 mg/L in the groundwater under the Department of Energy's Kansas City Plant (KCP). The study consisted of four distinct phases: a thorough review of the technical literature, a historical survey of arsenic use at the facility, a laboratory study of existing techniques for determining arsenic speciation, and a field program including water, soil, and sediment sampling. The historical survey and literature review demonstrated that plant activities had not released significant quantities of arsenic to the environment but that similar occurrences of arsenic in alluvial groundwater are widespread in the midwestern United States. Laboratory studies showed that a chromatographic separation technique was necessary to accurately determine arsenic speciation for the KCP groundwater samples. Field studies revealed that naturally occurring reducing conditions prevalent in the subsurface are responsible for dissolving arsenic previously sorbed by iron oxides. Indeed, the data demonstrated that the bulk arsenic concentration of site subsoils and sediments is {approximately}7 mg/kg, whereas the arsenic content of iron oxide subsamples is as high as 84 mg/kg. Literature showed that similar concentrations of arsenic in sediments occur naturally and are capable of producing the levels of arsenic found in groundwater monitoring wells at the KCP. The study concludes, therefore, that the arsenic present in the KCP groundwater is the result of natural phenomena. 44 refs., 8 figs., 14 tabs.

Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

Energy Technology Data Exchange (ETDEWEB)

Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q

2004-10-01

The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

International Nuclear Information System (INIS)

Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q.

2004-01-01

The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

Sulfate and glutathione enhanced arsenic accumulation by arsenic hyperaccumulator Pteris vittata L

International Nuclear Information System (INIS)

Wei Shuhe; Ma, Lena Q.; Saha, Uttam; Mathews, Shiny; Sundaram, Sabarinath; Rathinasabapathi, Bala; Zhou Qixing

2010-01-01

This experiment examined the effects of sulfate (S) and reduced glutathione (GSH) on arsenic uptake by arsenic hyperaccumulator Pteris vittata after exposing to arsenate (0, 15 or 30 mg As L -1 ) with sulfate (6.4, 12.8 or 25.6 mg S L -1 ) or GSH (0, 0.4 or 0.8 mM) for 2-wk. Total arsenic, S and GSH concentrations in plant biomass and arsenic speciation in the growth media and plant biomass were determined. While both S (18-85%) and GSH (77-89%) significantly increased arsenic uptake in P. vittata, GSH also increased arsenic translocation by 61-85% at 0.4 mM (p < 0.05). Sulfate and GSH did not impact plant biomass or arsenic speciation in the media and biomass. The S-induced arsenic accumulation by P. vittata was partially attributed to increased plant GSH (21-31%), an important non-enzymatic antioxidant countering oxidative stress. This experiment demonstrated that S and GSH can effectively enhance arsenic uptake and translocation by P. vittata. - Sulfate and glutathione increased arsenic uptake and translocation in Pteris vittata.

Continuous bioscorodite crystallization in CSTRs for arsenic removal and disposal.

Science.gov (United States)

González-Contreras, Paula; Weijma, Jan; Buisman, Cees J N

2012-11-15

In CSTRs, ferrous iron was biologically oxidized followed by crystallization of scorodite (FeAsO(4)·2H(2)O) at pH 1.2 and 72 °C. The CSTRs were fed with 2.8 g L(-1) arsenate and 2.4 g L(-1) ferrous and operated at an HRT of 40 h, without seed addition or crystal recirculation. Both oxidation and crystallization were stable for periods up to 200 days. The arsenic removal efficiency was higher than 99% at feed Fe/As molar ratios between 1 and 2, resulting in effluents with 29 ± 18 mg As L(-1). Arsenic removal decreased to 40% at feed Fe/As molar ratios between 2 and 5. Microorganisms were not affected by arsenic concentrations up to 2.8 g As(5+) L(-1). The bioscorodite solid yield was 3.2 g/g arsenic removed. Bioscorodite crystals precipitated as aggregates, causing scaling on the glass wall of the reactor. The observed morphology through SE microscopy of the precipitates appeared amorphous but XRD analysis confirmed that these were crystalline scorodite. Arsenic leaching of bioscorodite was 0.4 mg L(-1) after 100 days under TCLP conditions, but when jarosite had been co-precipitated leaching was higher at 0.8 g L(-1). The robustness of the continuous process, the high removal efficiency and the very low arsenic leaching rates from bioscorodite sludge make the process very suitable for arsenic removal and disposal. Copyright © 2012 Elsevier Ltd. All rights reserved.

The die is cast - Arsenic exposure in early life and disease susceptibility

Science.gov (United States)

Abstract Early life exposure to arsenic in humans and mice produces similar patterns of disease in later life. Given the long interval between exposure and effect, epigenetic effects of early life exposure to arsenic may account for development and progression of disease in bo...

Thorium coprecipitation method for spectrophotometric determination of arsenic (III) and arsenic (V) in groundwaters

International Nuclear Information System (INIS)

Tamari, Yuzo; Yamamoto, Nobuki; Tsuji, Haruo; Kusaka, Yuzuru

1989-01-01

A new coprecipitation method for the spectrophotometry of arsenic (III) and arsenic (V) in groundwater has been developed. Arsenic (III) and arsenic (V) were coprecipitated with thorium (IV) hydroxide from 1000ml of groundwater at pH9. The precipitate was centrifuged and then dissolved with hydrochloric acid. Arsenic (III) was spectrophotometrically determined by the usual silver diethylditiocarbamate (Ag-DDTC) method after generating the arsenic to arsine with sodium tetrahydroborate under masking the thorium with EDTA-NaF at pH6. From another portion of the same groundwater, both arsenic (III) and arsenic (V) were determined by the Ag-DDTC method after reducing all the arsenic to arsine with sodium tetrahydroborate at pH less than 1 in the presence of the EDTA-NaF. The concentration of arsenic (V) was obtained by subtracting that of arsenic (III) from the total for arsenic. (author)

Development of bacteria-based bioassays for arsenic detection in natural waters.

Science.gov (United States)

Diesel, Elizabeth; Schreiber, Madeline; van der Meer, Jan Roelof

2009-06-01

Arsenic contamination of natural waters is a worldwide concern, as the drinking water supplies for large populations can have high concentrations of arsenic. Traditional techniques to detect arsenic in natural water samples can be costly and time-consuming; therefore, robust and inexpensive methods to detect arsenic in water are highly desirable. Additionally, methods for detecting arsenic in the field have been greatly sought after. This article focuses on the use of bacteria-based assays as an emerging method that is both robust and inexpensive for the detection of arsenic in groundwater both in the field and in the laboratory. The arsenic detection elements in bacteria-based bioassays are biosensor-reporter strains; genetically modified strains of, e.g., Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Rhodopseudomonas palustris. In response to the presence of arsenic, such bacteria produce a reporter protein, the amount or activity of which is measured in the bioassay. Some of these bacterial biosensor-reporters have been successfully utilized for comparative in-field analyses through the use of simple solution-based assays, but future methods may concentrate on miniaturization using fiberoptics or microfluidics platforms. Additionally, there are other potential emerging bioassays for the detection of arsenic in natural waters including nematodes and clams.

Development of bacteria-based bioassays for arsenic detection in natural waters

Energy Technology Data Exchange (ETDEWEB)

Diesel, Elizabeth; Schreiber, Madeline [Virginia Tech, Department of Geosciences, Blacksburg, VA (United States); Meer, Jan Roelof van der [University of Lausanne, Department of Fundamental Microbiology, Lausanne (Switzerland)

2009-06-15

Arsenic contamination of natural waters is a worldwide concern, as the drinking water supplies for large populations can have high concentrations of arsenic. Traditional techniques to detect arsenic in natural water samples can be costly and time-consuming; therefore, robust and inexpensive methods to detect arsenic in water are highly desirable. Additionally, methods for detecting arsenic in the field have been greatly sought after. This article focuses on the use of bacteria-based assays as an emerging method that is both robust and inexpensive for the detection of arsenic in groundwater both in the field and in the laboratory. The arsenic detection elements in bacteria-based bioassays are biosensor-reporter strains; genetically modified strains of, e.g., Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Rhodopseudomonas palustris. In response to the presence of arsenic, such bacteria produce a reporter protein, the amount or activity of which is measured in the bioassay. Some of these bacterial biosensor-reporters have been successfully utilized for comparative in-field analyses through the use of simple solution-based assays, but future methods may concentrate on miniaturization using fiberoptics or microfluidics platforms. Additionally, there are other potential emerging bioassays for the detection of arsenic in natural waters including nematodes and clams. (orig.)

Speciation-dependent studies on removal of arsenic by iron-doped calcium alginate beads

International Nuclear Information System (INIS)

Banerjee, Anupam; Nayak, Dalia; Lahiri, Susanta

2007-01-01

This work aims to study the differential attitude of Fe-doped calcium alginate (Fe-CA) beads towards As(III) and As(V) compounds so that speciation-dependent environmentally sustainable methodologies can be developed for removal of arsenic from contaminated water. Throughout the experiment, 76 As has been used as precursor of stable arsenic. The affinity of As(V) towards the Fe-CA beads is greater than that of As(III). Removal efficiency of Fe-CA beads for As(V) increases with increasing number of beads and longer shaking times. At pH 3, 30 Fe-CA beads remove As(V) completely from a solution containing 20 mg kg -1 As(V). The technique has been successfully applied to the ground water collected from an arsenic-contaminated area

Arsenic removal by magnetic nanocrystalline barium hexaferrite

Energy Technology Data Exchange (ETDEWEB)

Patel, Hasmukh A.; Byun, Jeehye; Yavuz, Cafer T., E-mail: yavuz@kaist.ac.kr [Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST) (Korea, Republic of)

2012-07-15

Nanoscale magnetite (Fe{sub 3}O{sub 4}) (<15 nm) is known to remove arsenic efficiently but is very difficult to separate or require high magnetic fields to separate out from the waste water after treatment. Anisotropic hexagonal ferrite (BaFe{sub 12}O{sub 19}, BHF) is a well-known permanent magnet (i.e., fridge magnets) and attractive due to its low cost in making large quantities. BHF offers a viable alternative to magnetite nanocrystals for arsenic removal since it features surfaces similar to iron oxides but with much enhanced magnetism. Herein, we employ BHF nanocrystalline materials for the first time in arsenic removal from wastewater. Our results show better (75 %) arsenic removal than magnetite of the similar sizes. The BHF nanoparticles, 6.06 {+-} 0.52 nm synthesized by thermolysis method at 320 Degree-Sign C do not show hexagonal phase, however, subsequent annealing at 750 Degree-Sign C produced pure hexagonal BHF in >200 nm assemblies. By using BHF, we demonstrate that nanoparticle removal is more efficient and fixed bed type cartridge applications are more possible.

The die is cast: arsenic exposure in early life and disease susceptibility.

Science.gov (United States)

Thomas, David J

2013-12-16

Early life exposure to arsenic in humans and mice produces similar patterns of disease in later life. Given the long interval between exposure and effect, epigenetic effects of early life exposure to arsenic may account for the development and progression of disease in both species. Mode of action and dosimetric studies in the mouse may help assess the role of age at exposure as a factor in susceptibility to the toxic and carcinogenic effects of arsenic in humans.

Post-depositional behaviour of mercury and arsenic in submarine mine tailings deposited in Buyat Bay, North Sulawesi, Indonesia.

Science.gov (United States)

Shepherd, Thomas; Rumengan, Inneke; Sahami, Ali

2018-06-01

The post-depositional geochemical behaviour of mercury and arsenic in submarine mine tailings from the Mesel Gold Mine in Buyat Bay, North Sulawesi, Indonesia was assessed by in situ sampling of tailings porewaters using dialysis arrays and seawater and fish monitoring. Under steady-state conditions one year after cessation of tailings discharge, the calculated arsenic efflux incrementally added 0.8 μg/L of arsenic to the overlying seawater. The mercury efflux across the tailings-seawater interface was negligible. The arsenic and mercury concentration in seawater bottom samples monitored biannually during a 9-year post-closure program were 1.54 μg/L and tailings are geochemically stable. Copyright © 2018 Elsevier Ltd. All rights reserved.

Subsurface iron and arsenic removal for shallow tube well drinking water supply in rural Bangladesh.

Science.gov (United States)

van Halem, D; Olivero, S; de Vet, W W J M; Verberk, J Q J C; Amy, G L; van Dijk, J C

2010-11-01

Subsurface iron and arsenic removal has the potential to be a cost-effective technology to provide safe drinking water in rural decentralized applications, using existing shallow tube wells. A community-scale test facility in Bangladesh was constructed for injection of aerated water (∼1 m(3)) into an anoxic aquifer with elevated iron (0.27 mmolL(-1)) and arsenic (0.27μmolL(-1)) concentrations. The injection (oxidation) and abstraction (adsorption) cycles were monitored at the test facility and simultaneously simulated in the laboratory with anoxic column experiments. Dimensionless retardation factors (R) were determined to represent the delayed arrival of iron or arsenic in the well compared to the original groundwater. At the test facility the iron removal efficacies increased after every injection-abstraction cycle, with retardation factors (R(Fe)) up to 17. These high removal efficacies could not be explained by the theory of adsorptive-catalytic oxidation, and therefore other ((a)biotic or transport) processes have contributed to the system's efficacy. This finding was confirmed in the anoxic column experiments, since the mechanism of adsorptive-catalytic oxidation dominated in the columns and iron removal efficacies did not increase with every cycle (stable at R(Fe)=∼8). R(As) did not increase after multiple cycles, it remained stable around 2, illustrating that the process which is responsible for the effective iron removal did not promote the co-removal of arsenic. The columns showed that subsurface arsenic removal was an adsorptive process and only the freshly oxidized adsorbed iron was available for the co-adsorption of arsenic. This indicates that arsenic adsorption during subsurface treatment is controlled by the amount of adsorbed iron that is oxidized, and not by the amount of removed iron. For operational purposes this is an important finding, since apparently the oxygen concentration of the injection water does not control the subsurface arsenic

Arsenic in Food

Science.gov (United States)

... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Food Home Food Foodborne Illness & Contaminants Metals Arsenic Share ... of the Method used to Measure Arsenic in Foods Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, ...

Metallothionein blocks oxidative DNA damage induced by acute inorganic arsenic exposure

Energy Technology Data Exchange (ETDEWEB)

Qu, Wei, E-mail: qu@niehs.nih.gov; Waalkes, Michael P.

2015-02-01

We studied how protein metallothionein (MT) impacts arsenic-induced oxidative DNA damage (ODD) using cells that poorly express MT (MT-I/II double knockout embryonic cells; called MT-null cells) and wild-type (WT) MT competent cells. Arsenic (as NaAsO{sub 2}) was less cytolethal over 24 h in WT cells (LC{sub 50} = 11.0 ± 1.3 μM; mean ± SEM) than in MT-null cells (LC{sub 50} = 5.6 ± 1.2 μM). ODD was measured by the immuno-spin trapping method. Arsenic (1 or 5 μM; 24 h) induced much less ODD in WT cells (121% and 141% of control, respectively) than in MT-null cells (202% and 260%). In WT cells arsenic caused concentration-dependent increases in MT expression (transcript and protein), and in the metal-responsive transcription factor-1 (MTF-1), which is required to induce the MT gene. In contrast, basal MT levels were not detectable in MT-null cells and unaltered by arsenic exposure. Transfection of MT-I gene into the MT-null cells markedly reduced arsenic-induced ODD levels. The transport genes, Abcc1 and Abcc2 were increased by arsenic in WT cells but either showed no or very limited increases in MT-null cells. Arsenic caused increases in oxidant stress defense genes HO-1 and GSTα2 in both WT and MT-null cells, but to much higher levels in WT cells. WT cells appear more adept at activating metal transport systems and oxidant response genes, although the role of MT in these responses is unclear. Overall, MT protects against arsenic-induced ODD in MT competent cells by potential sequestration of scavenging oxidant radicals and/or arsenic. - Highlights: • Metallothionein blocks arsenic toxicity. • Metallothionein reduces arsenic-induced DNA damage. • Metallothionein may bind arsenic or radicals produced by arsenic.

Developing robust arsenic awareness prediction models using machine learning algorithms.

Science.gov (United States)

Singh, Sushant K; Taylor, Robert W; Rahman, Mohammad Mahmudur; Pradhan, Biswajeet

2018-04-01

Arsenic awareness plays a vital role in ensuring the sustainability of arsenic mitigation technologies. Thus far, however, few studies have dealt with the sustainability of such technologies and its associated socioeconomic dimensions. As a result, arsenic awareness prediction has not yet been fully conceptualized. Accordingly, this study evaluated arsenic awareness among arsenic-affected communities in rural India, using a structured questionnaire to record socioeconomic, demographic, and other sociobehavioral factors with an eye to assessing their association with and influence on arsenic awareness. First a logistic regression model was applied and its results compared with those produced by six state-of-the-art machine-learning algorithms (Support Vector Machine [SVM], Kernel-SVM, Decision Tree [DT], k-Nearest Neighbor [k-NN], Naïve Bayes [NB], and Random Forests [RF]) as measured by their accuracy at predicting arsenic awareness. Most (63%) of the surveyed population was found to be arsenic-aware. Significant arsenic awareness predictors were divided into three types: (1) socioeconomic factors: caste, education level, and occupation; (2) water and sanitation behavior factors: number of family members involved in water collection, distance traveled and time spent for water collection, places for defecation, and materials used for handwashing after defecation; and (3) social capital and trust factors: presence of anganwadi and people's trust in other community members, NGOs, and private agencies. Moreover, individuals' having higher social network positively contributed to arsenic awareness in the communities. Results indicated that both the SVM and the RF algorithms outperformed at overall prediction of arsenic awareness-a nonlinear classification problem. Lower-caste, less educated, and unemployed members of the population were found to be the most vulnerable, requiring immediate arsenic mitigation. To this end, local social institutions and NGOs could play a

Arsenic removal by magnetic nanocrystalline barium hexaferrite

International Nuclear Information System (INIS)

Patel, Hasmukh A.; Byun, Jeehye; Yavuz, Cafer T.

2012-01-01

Nanoscale magnetite (Fe 3 O 4 ) ( 12 O 19 , BHF) is a well-known permanent magnet (i.e., fridge magnets) and attractive due to its low cost in making large quantities. BHF offers a viable alternative to magnetite nanocrystals for arsenic removal since it features surfaces similar to iron oxides but with much enhanced magnetism. Herein, we employ BHF nanocrystalline materials for the first time in arsenic removal from wastewater. Our results show better (75 %) arsenic removal than magnetite of the similar sizes. The BHF nanoparticles, 6.06 ± 0.52 nm synthesized by thermolysis method at 320 °C do not show hexagonal phase, however, subsequent annealing at 750 °C produced pure hexagonal BHF in >200 nm assemblies. By using BHF, we demonstrate that nanoparticle removal is more efficient and fixed bed type cartridge applications are more possible.

Arsenic Speciation and Extraction and the Significance of Biodegradable Acid on Arsenic Removal—An Approach for Remediation of Arsenic-Contaminated Soil

Science.gov (United States)

Nguyen Van, Thinh; Osanai, Yasuhito; Do Nguyen, Hai; Kurosawa, Kiyoshi

2017-01-01

A series of arsenic remediation tests were conducted using a washing method with biodegradable organic acids, including oxalic, citric and ascorbic acids. Approximately 80% of the arsenic in one sample was removed under the effect of the ascorbic and oxalic acid combination, which was roughly twice higher than the effectiveness of the ascorbic and citric acid combination under the same conditions. The soils treated using biodegradable acids had low remaining concentrations of arsenic that are primarily contained in the crystalline iron oxides and organic matter fractions. The close correlation between extracted arsenic and extracted iron/aluminum suggested that arsenic was removed via the dissolution of Fe/Al oxides in soils. The fractionation of arsenic in four contaminated soils was investigated using a modified sequential extraction method. Regarding fractionation, we found that most of the soil contained high proportions of arsenic (As) in exchangeable fractions with phosphorus, amorphous oxides, and crystalline iron oxides, while a small amount of the arsenic fraction was organic matter-bound. This study indicated that biodegradable organic acids can be considered as a means for arsenic-contaminated soil remediation.

Producing air-stable monolayers of phosphorene and their defect engineering.

Science.gov (United States)

Pei, Jiajie; Gai, Xin; Yang, Jiong; Wang, Xibin; Yu, Zongfu; Choi, Duk-Yong; Luther-Davies, Barry; Lu, Yuerui

2016-01-22

It has been a long-standing challenge to produce air-stable few- or monolayer samples of phosphorene because thin phosphorene films degrade rapidly in ambient conditions. Here we demonstrate a new highly controllable method for fabricating high quality, air-stable phosphorene films with a designated number of layers ranging from a few down to monolayer. Our approach involves the use of oxygen plasma dry etching to thin down thick-exfoliated phosphorene flakes, layer by layer with atomic precision. Moreover, in a stabilized phosphorene monolayer, we were able to precisely engineer defects for the first time, which led to efficient emission of photons at new frequencies in the near infrared at room temperature. In addition, we demonstrate the use of an electrostatic gate to tune the photon emission from the defects in a monolayer phosphorene. This could lead to new electronic and optoelectronic devices, such as electrically tunable, broadband near infrared lighting devices operating at room temperature.

Understanding arsenic metabolism through spectroscopic determination of arsenic in human urine

OpenAIRE

Brima, Eid I.; Jenkins, Richard O.; Haris, Parvez I.

2006-01-01

In this review we discuss a range of spectroscopic techniques that are currently used for analysis of arsenic in human urine for understanding arsenic metabolism and toxicity, especially in relation to genetics/ethnicity, ingestion studies and exposure to arsenic through drinking water and diet. Spectroscopic techniques used for analysis of arsenic in human urine include inductively coupled plasma mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS), hydride ...

Arsenic speciation in moso bamboo shoot - A terrestrial plant that contains organoarsenic species

Energy Technology Data Exchange (ETDEWEB)

Zhao Rui [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084, P.R. China (China); Zhao Mengxia [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China); Wang Hui [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China); Taneike, Yasuhito [Shimadzu Co Ltd, Spectroscopy Business Unit Analytical Instruments Div, Nakagyo Ku, Kyoto, 6048511 (Japan); Zhang Xinrong [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China)]. E-mail: xrzhang@chem.tsinghua.edu.cn

2006-12-01

Arsenic is predominantly found as an inorganic species in most terrestrial plants. However, we found that a significant proportion of organic arsenic was present in moso bamboo (Phyllostachys pubescens Mazel) shoot in a market survey of arsenic species in edible terrestrial plants. Moso bamboo shoots from different producing areas in China were collected for analysis to confirm the ubiquity of methylated arsenic species. The total arsenic concentrations of bamboo shoots were determined by hydride generation coupled atomic fluorescence spectrometry (HG-AFS), ranging from 27.7 to 94.0 {mu}g/kg. Information about arsenic species was acquired from cold trap-hydride generation-atomic absorption spectrometry (CT-HG-AAS). Dimethylarsinic acid (DMA) was present in the amount of 13.9% to 44.9% of sum of the arsenic species in all these samples. Monomethylarsonic acid (MMA) and trimethylarsine oxide (TMAO) were also detected in certain samples in the range of 4.2-16.5% and 11.8-18.4%, respectively. In addition, bamboo shoots collected in winter were found to have more total arsenic and organic arsenic than those collected in spring. To investigate the source of the organic arsenic in moso bamboo shoots, arsenic species in the rhizosphere soils of the plants were examined. The absence of organic arsenic in soils would suggest the possibility of formation of methylated arsenic in the plants. In addition, studies of arsenic speciation in the peel and core of winter bamboo shoots showed that all the cores contained organic arsenic while no organic arsenic was detected in the peels. The study provides useful information for better understanding of the distribution of arsenic species in terrestrial plants.

Chronic Arsenic Toxicity: Statistical Study of the Relationships Between Urinary Arsenic, Selenium and Antimony

OpenAIRE

Analía Boemo, BS; Irene María Lomniczi, PhD; Elsa Mónica Farfán Torres, PhD

2012-01-01

Background. The groundwater of Argentina’s Chaco plain presents arsenic levels above those suitable for human consumption. Studies suggest skin disorders among local populations caused by arsenic intake. The relationship between urinary arsenic and arsenic in drinking water is well known, but urinary arsenic alone is not enough for risk assessment due to modulating factors such as the intake of selenium and antimony. Objectives. Determining the relationship between urinary arsenic, seleniu...

Comparison of arsenic uptake ability of barnyard grass and rice species for arsenic phytoremediation.

Science.gov (United States)

Sultana, Razia; Kobayashi, Katsuichiro; Kim, Ki-Hyun

2015-01-01

In this research, the relative performance in arsenic (As) remediation was evaluated among some barnyard grass and rice species under hydroponic conditions. To this end, four barnyard grass varieties and two rice species were selected and tested for their remediation potential of arsenic. The plants were grown for 2 weeks in As-rich solutions up to 10 mg As L(-1) to measure their tolerance to As and their uptake capabilities. Among the varieties of plants tested in all treatment types, BR-29 rice absorbed the highest amount of As in the root, while Nipponbare translocated the maximum amount of As in the shoot. Himetainubie barnyard grass produced the highest biomass, irrespective of the quantity of As in the solution. In all As-treated solutions, the maximum uptake of As was found in BR-29 followed by Choto shama and Himetainubie. In contrast, while the bioaccumulation factor was found to be the highest in Nipponbare followed by BR-29 and Himetainubie. The results suggest that both Choto shama and Himetainubie barnyard grass varieties should exhibit a great potential for As removal, while BR-29 and Nipponbare rice species are the best option for arsenic phytoremediation.

Dimethylthioarsinic anhydride: A standard for arsenic speciation

International Nuclear Information System (INIS)

Fricke, Michael; Zeller, Matthias; Cullen, William; Witkowski, Mark; Creed, John

2007-01-01

Dimethylthioarsinic acid (DMTA V ) has recently been identified in biological, dietary and environmental matrices. The relevance of this compound to the toxicity of arsenic in humans is unknown and further exposure assessment and metabolic studies are difficult to conduct because of the unavailability of a well characterized standard. The synthesis of DMTA V was accomplished by the reaction of dimethylarsinic acid (DMA V ) with hydrogen sulfide. The initial reaction product produced is DMTA V but multiple products over the course of the reaction are also observed. Therefore, a chromatographic separation was developed to monitor the reaction progress via LC-ICP-MS. In this synthesis, conversion of DMA V to DMTA V was not taken to completion to avoid the production of side products. The product was isolated from the starting material by standard organic techniques. Single crystal diffraction demonstrated that solid DMTA V is present in the form of the oxygen-bridged dimethylthioarsinic anhydride. Dissolution of the anhydride in water produces the acid form of DMTA V and the aqueous phase DMTA V provided a characteristic molecular ion of m/z 155 by LC-ESI-MS. The synthesis and isolation of dimethylthioarsinic anhydride provides a stable crystalline standard suitable for identification, toxicological study and exposure assessment of dimethylthioarsinic acid

Approaches to increase arsenic awareness in Bangladesh: an evaluation of an arsenic education program.

Science.gov (United States)

George, Christine Marie; Factor-Litvak, Pam; Khan, Khalid; Islam, Tariqul; Singha, Ashit; Moon-Howard, Joyce; van Geen, Alexander; Graziano, Joseph H

2013-06-01

The objective of this study was to design and evaluate a household-level arsenic education and well water arsenic testing intervention to increase arsenic awareness in Bangladesh. The authors randomly selected 1,000 study respondents located in 20 villages in Singair, Bangladesh. The main outcome was the change in knowledge of arsenic from baseline to follow-up 4 to 6 months after the household received the intervention. This was assessed through a pre- and postintervention quiz concerning knowledge of arsenic. Respondents were between 18 and 102 years of age, with an average age of 37 years; 99.9% were female. The knowledge of arsenic quiz scores for study participants were significantly higher at follow-up compared with baseline. The intervention was effective in increasing awareness of the safe uses of arsenic-contaminated water and dispelling the misconception that boiling water removes arsenic. At follow-up, nearly all respondents were able to correctly identify the meaning of a red (contaminated) and green (arsenic safe) well relative to arsenic (99%). The educational program also significantly increased the proportion of respondents who were able to correctly identify the health implications of arsenic exposure. However, the intervention was not effective in dispelling the misconceptions in the population that arsenicosis is contagious and that illnesses such as cholera, diarrhea, and vomiting could be caused by arsenic. Further research is needed to develop effective communication strategies to dispel these misconceptions. This study demonstrates that a household-level arsenic educational program can be used to significantly increase arsenic awareness in Bangladesh.

Arsenic speciation in saliva of acute promyelocytic leukemia patients undergoing arsenic trioxide treatment

OpenAIRE

Chen, Baowei; Cao, Fenglin; Yuan, Chungang; Lu, Xiufen; Shen, Shengwen; Zhou, Jin; Le, X. Chris

2013-01-01

Arsenic trioxide has been successfully used as a therapeutic in the treatment of acute promyelocytic leukemia (APL). Detailed monitoring of the therapeutic arsenic and its metabolites in various accessible specimens of APL patients can contribute to improving treatment efficacy and minimizing arsenic-induced side effects. This article focuses on the determination of arsenic species in saliva samples from APL patients undergoing arsenic treatment. Saliva samples were collected from nine APL pa...

Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species

International Nuclear Information System (INIS)

Norton, Gareth J.; Adomako, Eureka E.; Deacon, Claire M.; Carey, Anne-Marie; Price, Adam H.; Meharg, Andrew A.

2013-01-01

Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. -- Highlights: ► High soil arsenic and organic matter caused a reduction in plant growth. ► A delayed flowering time was observed in high arsenic and organic matter soil. ► Total grain arsenic increased in high arsenic and organic matter soil. ► Percentage organic arsenic in the grain altered in arsenic and organic matter soil. -- The addition of high amounts of organic matter to soils led to an increase in total rice grain arsenic, as well as alteration in the percentage arsenic species in the rice grains

Removing Arsenic from Contaminated Drinking Water in Rural Bangladesh: Recent Fieldwork Results and Policy Implications

Energy Technology Data Exchange (ETDEWEB)

Mathieu, Johanna L.; Gadgil, Ashok J.; Kowolik, Kristin; Addy, Susan E.A.

2009-09-17

ARUBA (Arsenic Removal Using Bottom Ash) has proven effective at removing high concentrations of arsenic from drinking water in Bangladesh. During fieldwork in four sub-districts of the country, ARUBA reduced arsenic levels ranging from 200 to 900 ppb to below the Bangladesh standard of 50 ppb. The technology is cost-effective because the substrate--bottom ash from coal fired power plants--is a waste material readily available in South Asia. In comparison to similar technologies, ARUBA uses less media for arsenic removal due to its high surface area to volume ratio. Hence, less waste is produced. A number of experiments were conducted in Bangladesh to determine the effectiveness of various water treatment protocols. It was found that (1) ARUBA removes more than half of the arsenic from water within five minutes of treatment, (2) ARUBA, that has settled at the bottom of a treatment vessel, continues to remove arsenic for 2-3 days, (3) ARUBA's arsenic removal efficiency can be improved through sequential partial dosing (adding a given amount of ARUBA in fractions versus all at once), and (4) allowing water to first stand for two to three days followed by treatment with ARUBA produced final arsenic levels ten times lower than treating water directly out of the well. Our findings imply a number of tradeoffs between ARUBA's effective arsenic removal capacity, treatment system costs, and waste output. These tradeoffs, some a function of arsenic-related policies in Bangladesh (e.g., waste disposal regulations), must be considered when designing an arsenic removal system. We propose that the most attractive option is to use ARUBA in communityscale water treatment centers, installed as public-private partnerships, in Bangladeshi villages.

Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Shen, Hui; Niu, Qiang; Xu, Mengchuan; Rui, Dongsheng; Xu, Shangzhi; Feng, Gangling; Ding, Yusong; Li, Shugang; Jing, Mingxia

2016-02-06

Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (piAs), monomethyl arsenic (MMA), dimethyl arsenic (DMA), and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD): 1.00; 95% confidence interval (CI): 0.60-1.40; p< 0.00001) and MMA (SMD: 0.49; 95% CI: 0.21-0.77; p = 0.0006) also increase, while the percentage of DMA (SMD: -0.57; 95% CI: -0.80--0.31; p< 0.0001), primary methylation index (SMD: -0.57; 95% CI: -0.94--0.20; p = 0.002), and secondary methylation index (SMD: -0.27; 95% CI: -0.46--0.90; p = 0.004) decrease. Smoking, drinking, and older age can reduce arsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

Environmental Source of Arsenic Exposure

OpenAIRE

Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

2014-01-01

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a ...

Atomic scale simulations of arsenic ion implantation and annealing in silicon

International Nuclear Information System (INIS)

Caturla, M.J.; Diaz de la Rubia, T.; Jaraiz, M.

1995-01-01

We present results of multiple-time-scale simulations of 5, 10 and 15 keV low temperature ion implantation of arsenic on silicon (100), followed by high temperature anneals. The simulations start with a molecular dynamics (MD) calculation of the primary state of damage after 10ps. The results are then coupled to a kinetic Monte Carlo (MC) simulation of bulk defect diffusion and clustering. Dose accumulation is achieved considering that at low temperatures the damage produced in the lattice is stable. After the desired dose is accumulated, the system is annealed at 800 degrees C for several seconds. The results provide information on the evolution for the damage microstructure over macroscopic length and time scales and affords direct comparison to experimental results. We discuss the database of inputs to the MC model and how it affects the diffusion process

Application of microwave digestion to the preparation of sediment samples for arsenic speciation

Energy Technology Data Exchange (ETDEWEB)

Demesmay, C. [Lab. des Sciences Analytiques, Univ. Claude Bernard Lyon I, Villeurbanne (France); Olle, M. [Service Central d`Analyse du CNRS, Vernaison (France)

1997-04-01

Several extraction procedures are described allowing arsenic speciation in sediments. The extraction of organometallic compounds such as dimethylarsinic acid or monomethylarsonic acid is quite simple since these compounds are stable in the different extraction media (HCl/ HNO{sub 3}, H{sub 3}PO{sub 4}, ammonium oxalate) and are easily released independent of the extraction mode (magnetic stirring or microwave solubilization). Extraction yields are higher than 96% for these two arsenic forms. An HCl/HNO{sub 3} microwave solubilization procedure allows the quantitative solubilization of mineral arsenic, but the differentiation between the two oxidation states is not possible owing to the oxidation of As(III) to As(V). Extractions with orthophosphoric acid or ammonium oxalate allow the solubilization of mineral arsenic with extraction yields ranging from 90 to 95% and the differentiation between As(III) and As(V). Nevertheless, the amount of As(III) is underestimated owing to its partial oxidation. The usefulness and advantages of microwave solubilization compared with conventional extraction procedures are discussed. (orig.). With 3 figs., 2 tabs.

Arsenic volatilization in model anaerobic biogas digesters

International Nuclear Information System (INIS)

Mestrot, Adrien; Xie, Wan-Ying; Xue, Ximei; Zhu, Yong-Guan

2013-01-01

Highlights: • Arsenic is volatilized form all model anaerobic digesters, including the non-treated ones. • Volatile As species can be identified and quantified in all digesters. • Non-arsenic treated digesters volatilization rates are higher than Roxarsone treated ones. - Abstract: Arsenic is a class 1 non-threshold carcinogen which is highly ubiquitous. Arsenic undergoes many different transformations (biotic or abiotic) between and within environmental compartments, leading to a number of different chemical species possessing different properties and toxicities. One specific transformation is As biotic volatilization which is coupled with As biomethylation and has been scarcely studied due to inherent sampling issues. Arsenic methylation/volatilization is also linked with methanogenesis and occurs in anaerobic environments. In China, rice straw and animal manure are very often used to produce biogas and both can contain high amounts of As, especially if the rice is grown in areas with heavy mining or smelting industries and if Roxarsone is fed to the animals. Roxarsone is an As-containing drug which is widely used in China to control coccidian intestinal parasites, to improve feed efficiency and to promote rapid growth. Previous work has shown that this compound degrades to inorganic As under anaerobic conditions. In this study the focus is on biotic transformations of As in small microcosms designed as biogas digester models (BDMs) using recently validated As traps, thus, enabling direct quantification and identification of volatile As species. It is shown that although there was a loss of soluble As in the BDMs, their conditions favored biomethylation. All reactors produced volatile As, especially the monomethylarsonic acid spiked ones with 413 ± 148 ng As (mean ± SD, n = 3) which suggest that the first methylation step, from inorganic As, is a limiting factor. The most abundant species was trimethylarsine, but the toxic arsine was present in the

Correlation of arsenic exposure through drinking groundwater and urinary arsenic excretion among adults in Pakistan.

Science.gov (United States)

Ahmed, Mubashir; Fatmi, Zafar; Ali, Arif

2014-01-01

Long-term exposure to arsenic has been associated with manifestation of skin lesions (melanosis/keratosis) and increased risk of internal cancers (lung/bladder). The objective of the study described here was to determine the relationship between exposure of arsenic through drinking groundwater and urinary arsenic excretion among adults > or =15 years of age living in Khairpur district, Pakistan. Total arsenic was determined in drinking groundwater and in spot urine samples of 465 randomly selected individuals through hydride generation-atomic absorption spectrometry. Spearman's rank correlation coefficient was calculated between arsenic in drinking groundwater and arsenic excreted in urine. The median arsenic concentration in drinking water was 2.1 microg/L (range: 0.1-350), and in urine was 28.5 microg/L (range: 0.1-848). Positive correlation was found between total arsenic in drinking water and in urine (r = .52, p arsenic may be used as a biomarker of arsenic exposure through drinking water.

Urinary Arsenic Metabolites of Subjects Exposed to Elevated Arsenic Present in Coal in Shaanxi Province, China

Directory of Open Access Journals (Sweden)

Linsheng Yang

2011-06-01

Full Text Available In contrast to arsenic (As poisoning caused by naturally occurring inorganic arsenic-contaminated water consumption, coal arsenic poisoning (CAP induced by elevated arsenic exposure from coal combustion has rarely been reported. In this study, the concentrations and distributions of urinary arsenic metabolites in 57 volunteers (36 subjects with skin lesions and 21 subjects without skin lesions, who had been exposed to elevated levels of arsenic present in coal in Changshapu village in the south of Shaanxi Province (China, were reported. The urinary arsenic species, including inorganic arsenic (iAs [arsenite (iAsIII and arsenate (iAsV], monomethylarsonic acid (MMAV and dimethylarsinic acid (DMAV, were determined by high-performance liquid chromatography (HPLC combined with inductively coupled plasma mass spectroscopy (ICP-MS. The relative distributions of arsenic species, the primary methylation index (PMI = MMAV/iAs and the secondary methylation index (SMI = DMAV/MMAV were calculated to assess the metabolism of arsenic. Subjects with skin lesions had a higher concentration of urinary arsenic and a lower arsenic methylation capability than subjects without skin lesions. Women had a significantly higher methylation capability of arsenic than men, as defined by a higher percent DMAV and SMI in urine among women, which was the one possible interpretation of women with a higher concentration of urinary arsenic but lower susceptibility to skin lesions. The findings suggested that not only the dose of arsenic exposure but also the arsenic methylation capability have an impact on the individual susceptibility to skin lesions induced by coal arsenic exposure.

Delineating sources of groundwater recharge in an arsenic-affected Holocene aquifer in Cambodia using stable isotope-based mixing models

Science.gov (United States)

Richards, Laura A.; Magnone, Daniel; Boyce, Adrian J.; Casanueva-Marenco, Maria J.; van Dongen, Bart E.; Ballentine, Christopher J.; Polya, David A.

2018-02-01

Chronic exposure to arsenic (As) through the consumption of contaminated groundwaters is a major threat to public health in South and Southeast Asia. The source of As-affected groundwaters is important to the fundamental understanding of the controls on As mobilization and subsequent transport throughout shallow aquifers. Using the stable isotopes of hydrogen and oxygen, the source of groundwater and the interactions between various water bodies were investigated in Cambodia's Kandal Province, an area which is heavily affected by As and typical of many circum-Himalayan shallow aquifers. Two-point mixing models based on δD and δ18O allowed the relative extent of evaporation of groundwater sources to be estimated and allowed various water bodies to be broadly distinguished within the aquifer system. Model limitations are discussed, including the spatial and temporal variation in end member compositions. The conservative tracer Cl/Br is used to further discriminate between groundwater bodies. The stable isotopic signatures of groundwaters containing high As and/or high dissolved organic carbon plot both near the local meteoric water line and near more evaporative lines. The varying degrees of evaporation of high As groundwater sources are indicative of differing recharge contributions (and thus indirectly inferred associated organic matter contributions). The presence of high As groundwaters with recharge derived from both local precipitation and relatively evaporated surface water sources, such as ponds or flooded wetlands, are consistent with (but do not provide direct evidence for) models of a potential dual role of surface-derived and sedimentary organic matter in As mobilization.

Developmental and genetic modulation of arsenic biotransformation: A gene by environment interaction?

International Nuclear Information System (INIS)

Meza, Mercedes; Gandolfi, A. Jay; Klimecki, Walter T.

2007-01-01

The complexity of arsenic toxicology has confounded the identification of specific pathways of disease causation. One focal point of arsenic research is aimed at fully characterizing arsenic biotransformation in humans, a process that appears to be quite variable, producing a mixture of several arsenic species with greatly differing toxic potencies. In an effort to characterize genetic determinants of variability in arsenic biotransformation, a genetic association study of 135 subjects in western Sonora, Mexico was performed by testing 23 polymorphic sites in three arsenic biotransformation candidate genes. One gene, arsenic 3 methyltransferase (AS3MT), was strongly associated with the ratio of urinary dimethylarsinic acid to monomethylarsonic acid (D/M) in children (7-11 years) but not in adults (18-79 years). Subsequent analyses revealed that the high D/M values associated with variant AS3MT alleles were primarily due to lower levels of monomethylarsonic acid as percent of total urinary arsenic (%MMA5). In light of several reports of arsenic-induced disease being associated with relatively high %MMA5 levels, these findings raise the possibility that variant AS3MT individuals may suffer less risk from arsenic exposure than non-variant individuals. These analyses also provide evidence that, in this population, regardless of AS3MT variant status, children tend to have lower %MMA5 values than adults, suggesting that the global developmental regulation of arsenic biotransformation may interact with genetic variants in metabolic genes to result in novel genetic effects such as those in this report

Characterization of arsenic resistant bacteria from arsenic rich groundwater of West Bengal, India.

Science.gov (United States)

Sarkar, Angana; Kazy, Sufia K; Sar, Pinaki

2013-03-01

Sixty-four arsenic (As) resistant bacteria isolated from an arsenic rich groundwater sample of West Bengal were characterized to investigate their potential role in subsurface arsenic mobilization. Among the isolated strains predominance of genera Agrobacterium/Rhizobium, Ochrobactrum and Achromobacter which could grow chemolitrophically and utilize arsenic as electron donor were detected. Higher tolerance to As(3+) [maximum tolerable concentration (MTC): ≥10 mM], As(5+) (MTC: ≥100 mM) and other heavy metals like Cu(2+), Cr(2+), Ni(2+) etc. (MTC: ≥10 mM), presence of arsenate reductase and siderophore was frequently observed among the isolates. Ability to produce arsenite oxidase and phosphatase enzyme was detected in 50 and 34 % of the isolates, respectively. Although no direct correlation among taxonomic identity of bacterial strains and their metabolic abilities as mentioned above was apparent, several isolates affiliated to genera Ochrobactrum, Achromobacter and unclassified Rhizobiaceae members were found to be highly resistant to As(3+) and As(5+) and positive for all the test properties. Arsenate reductase activity was found to be conferred by arsC gene, which in many strains was coupled with arsenite efflux gene arsB as well. Phylogenetic incongruence between the 16S rRNA and ars genes lineages indicated possible incidence of horizontal gene transfer for ars genes. Based on the results we propose that under the prevailing low nutrient condition inhabitant bacteria capable of using inorganic electron donors play a synergistic role wherein siderophores and phosphatase activities facilitate the release of sediment bound As(5+), which is subsequently reduced by arsenate reductase resulting into the mobilization of As(3+) in groundwater.

Arsenic species excretion after dimercaptopropanesulfonic acid (DMPS) treatment of an acute arsenic trioxide poisoning

Energy Technology Data Exchange (ETDEWEB)

Heinrich-Ramm, R. [Ordinariat fuer Arbeitsmedizin der Universitaet Hamburg und Zentralinstitut fuer Arbeitsmedizin, Hamburg (Germany); Schaller, K.H.; Angerer, J. [Institut und Poliklinik fuer Arbeits-, Sozial- und Umweltmedizin der Universitaet Erlangen-Nuernberg, Schillerstr. 25, 91054 Erlangen (Germany); Horn, J. [Medizinische Klinik II, Toxikologische-internistische Intensivstation, Klinikum Nuernberg, Nuernberg (Germany)

2003-02-01

We studied the urinary excretion of the different arsenic species in urine samples from a young man who tried to commit suicide by ingesting about 0.6 g arsenic trioxide. He received immediate therapy with dimercaptopropanesulfonic acid (DMPS) after his delivery into the hospital. We assessed urinary arsenite (inorganic trivalent arsenic), arsenate (inorganic pentavalent arsenic), pentavalent dimethylarsinic acid (DMA) and pentavalent monomethylarsonic acid (MMA) in urine with ion-exchange chromatography and on-line hydride-technique atomic absorption spectrometry. The predominant amount of the excreted arsenic was unchanged trivalent inorganic arsenic (37.4%), followed by pentavalent inorganic arsenic (2.6%), MMA (2.1%), DMA (0.2%) and one unidentified arsenic species (0.7%, if calculated as DMA). In the first urine voiding in the clinic, the total arsenic concentration was 215 mg/l, which fell 1000-fold after 8 days of DMPS therapy. A most striking finding was the almost complete inhibition of the second methylation step in arsenic metabolism. As mechanisms for the reduced methylation efficiency, the saturation of the enzymatic process of arsenic methylation, the high dosage of antidote DMPS, which might inhibit the activity of the methyl transferases, and analytical reasons are discussed. The high dosage of DMPS is the most likely explanation. The patient left the hospital after a 12-day treatment with antidote. (orig.)

Arsenic waste management: a critical review of testing and disposal of arsenic-bearing solid wastes generated during arsenic removal from drinking water.

Science.gov (United States)

Clancy, Tara M; Hayes, Kim F; Raskin, Lutgarde

2013-10-01

Water treatment technologies for arsenic removal from groundwater have been extensively studied due to widespread arsenic contamination of drinking water sources. Central to the successful application of arsenic water treatment systems is the consideration of appropriate disposal methods for arsenic-bearing wastes generated during treatment. However, specific recommendations for arsenic waste disposal are often lacking or mentioned as an area for future research and the proper disposal and stabilization of arsenic-bearing waste remains a barrier to the successful implementation of arsenic removal technologies. This review summarizes current disposal options for arsenic-bearing wastes, including landfilling, stabilization, cow dung mixing, passive aeration, pond disposal, and soil disposal. The findings from studies that simulate these disposal conditions are included and compared to results from shorter, regulatory tests. In many instances, short-term leaching tests do not adequately address the range of conditions encountered in disposal environments. Future research directions are highlighted and include establishing regulatory test conditions that align with actual disposal conditions and evaluating nonlandfill disposal options for developing countries.

Binding of Industrial Deposits of Heavy Metals and Arsenic in the Soil by 3-Aminopropyltrimethoxysilane

Directory of Open Access Journals (Sweden)

Grzesiak Piotr

2014-06-01

Full Text Available The results of the research studies concerning binding of heavy metals and arsenic (HM+As, occurring in soils affected by emissions from Głogów Copper Smelter and Refinery, by silane nanomaterial have been described. The content of heavy metals and arsenic was determined by AAS and the effectiveness of heavy metals and arsenic binding by 3-Aminopropyltrimethoxysilane was examined. The total leaching level of impurities in those fractions was 73.26% Cu, 74.7% – Pb, 79.5% Zn, 65.81% – Cd and 55.55% As. The studies demonstrated that the total binding of heavy metals and arsenic with nanomaterial in all fractions was about as follows: 20.5% Cu, 9.5% Pb, 7.1% Zn, 25.3% Cd and 10.89% As. The results presented how the safety of food can be cultivated around industrial area, as the currently used soil stabilization technique of HM by soil pH does not guarantee their stable blocking in a sorptive complex.

The feasibility of well-logging measurements of arsenic levels using neutron-activation analysis

Science.gov (United States)

Oden, C.P.; Schweitzer, J.S.; McDowell, G.M.

2006-01-01

Arsenic is an extremely toxic metal, which poses a significant problem in many mining environments. Arsenic contamination is also a major problem in ground and surface waters. A feasibility study was conducted to determine if neutron-activation analysis is a practical method of measuring in situ arsenic levels. The response of hypothetical well-logging tools to arsenic was simulated using a readily available Monte Carlo simulation code (MCNP). Simulations were made for probes with both hyperpure germanium (HPGe) and bismuth germanate (BGO) detectors using accelerator and isotopic neutron sources. Both sources produce similar results; however, the BGO detector is much more susceptible to spectral interference than the HPGe detector. Spectral interference from copper can preclude low-level arsenic measurements when using the BGO detector. Results show that a borehole probe could be built that would measure arsenic concentrations of 100 ppm by weight to an uncertainty of 50 ppm in about 15 min. ?? 2006 Elsevier Ltd. All rights reserved.

Arsenic accumulation by two brake ferns growing on an arsenic mine and their potential in phytoremediation.

Science.gov (United States)

Wei, Chao-Yang; Chen, Tong-Bin

2006-05-01

In an area near an arsenic mine in Hunan Province of south China, soils were often found with elevated arsenic levels. A field survey was conducted to determine arsenic accumulation in 8 Cretan brake ferns (Pteris cretica) and 16 Chinese brake ferns (Pteris vittata) growing on these soils. Three factors were evaluated: arsenic concentration in above ground parts (fronds), arsenic bioaccumulation factor (BF; ratio of arsenic in fronds to soil) and arsenic translocation factor (TF; ratio of arsenic in fronds to roots). Arsenic concentrations in the fronds of Chinese brake fern were 3-704 mg kg-1, the BFs were 0.06-7.43 and the TFs were 0.17-3.98, while those in Cretan brake fern were 149-694 mg kg-1, 1.34-6.62 and 1.00-2.61, respectively. Our survey showed that both ferns were capable of arsenic accumulation under field conditions. With most of the arsenic being accumulated in the fronds, these ferns have potential for use in phytoremediation of arsenic contaminated soils.

Arsenic Methyltransferase

Science.gov (United States)

The metalloid arsenic enters the environment by natural processes (volcanic activity, weathering of rocks) and by human activity (mining, smelting, herbicides and pesticides). Although arsenic has been exploited for homicidal and suicidal purposes since antiquity, its significan...

Arsenic-Induced Genotoxicity and Genetic Susceptibility to Arsenic-Related Pathologies

Directory of Open Access Journals (Sweden)

Fabrizio Bianchi

2013-04-01

Full Text Available The arsenic (As exposure represents an important problem in many parts of the World. Indeed, it is estimated that over 100 million individuals are exposed to arsenic, mainly through a contamination of groundwaters. Chronic exposure to As is associated with adverse effects on human health such as cancers, cardiovascular diseases, neurological diseases and the rate of morbidity and mortality in populations exposed is alarming. The purpose of this review is to summarize the genotoxic effects of As in the cells as well as to discuss the importance of signaling and repair of arsenic-induced DNA damage. The current knowledge of specific polymorphisms in candidate genes that confer susceptibility to arsenic exposure is also reviewed. We also discuss the perspectives offered by the determination of biological markers of early effect on health, incorporating genetic polymorphisms, with biomarkers for exposure to better evaluate exposure-response clinical relationships as well as to develop novel preventative strategies for arsenic- health effects.

Combining Ferric Salt and Cactus Mucilage for Arsenic Removal from Water.

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Fox, Dawn I; Stebbins, Daniela M; Alcantar, Norma A

2016-03-01

New methods to remediate arsenic-contaminated water continue to be studied, particularly to fill the need for accessible methods that can significantly impact developing communities. A combination of cactus mucilage and ferric (Fe(III)) salt was investigated as a flocculation-coagulation system to remove arsenic (As) from water. As(V) solutions, ferric nitrate, and mucilage suspensions were mixed and left to stand for various periods of time. Visual and SEM observations confirmed the flocculation action of the mucilage as visible flocs formed and settled to the bottom of the tubes within 3 min. The colloidal suspensions without mucilage were stable for up to 1 week. Sample aliquots were tested for dissolved and total arsenic by ICP-MS and HGAFS. Mucilage treatment improved As removal (over Fe(III)-only treatment); the system removed 75-96% As in 30 min. At neutral pH, removal was dependent on Fe(III) and mucilage concentration and the age of the Fe(III) solution. The process is fast, achieving maximum removal in 30 min, with the majority of As removed in 10-15 min. Standard jar tests with 1000 μg/L As(III) showed that arsenic removal and settling rates were pH-dependent; As removal was between 52% (high pH) and 66% (low pH).

Effectiveness of household reverse-osmosis systems in a Western U.S. region with high arsenic in groundwater

International Nuclear Information System (INIS)

Walker, Mark; Seiler, Ralph L.; Meinert, Michael

2008-01-01

It is well known to the public in Lahontan Valley in rural Nevada, USA, that local aquifers produce water with varied, but sometimes very high concentrations of arsenic (> 4 ppm). As a result, many residents of the area have installed household reverse-osmosis (RO) systems to produce drinking water. We examined performance of RO systems and factors associated with arsenic removal efficiency in 59 households in Lahontan Valley. The sampling results indicated that RO systems removed an average of 80.2% of arsenic from well water. In 18 of the 59 households, arsenic concentrations exceeded 10 ppb in treated water, with a maximum in treated water of 180 ppb. In 3 of the 59 households, RO treatment had little effect on specific conductance, indicating that the RO system was not working properly. Two main factors lead to arsenic levels in treated water exceeding drinking-water standards in the study area. First, arsenic concentrations were high enough in some Lahontan Valley wells that arsenic levels exceeded 10 ppb even though RO treatment removed more than 95% of the arsenic. Second, trivalent As +3 was the dominant arsenic species in approximately 15% of the wells, which significantly reduced treatment efficiency. Measurements of specific conductance indicated that efficiency in reducing arsenic levels did not always correlate with reductions in total dissolved solids. As a consequence, improvements in taste of the water or simple measurements of specific conductance made by technicians to test RO systems can mislead the public into assuming the water meets safety standards. Actual measurements of treated water are necessary to assure that household RO systems are reducing arsenic concentrations to safe levels, particularly in areas where groundwater has high arsenic concentrations or where As +3 is the dominant species

AN INVESTIGATION OF ARSENIC MOBILITY FROM IRON OXIDE SOLIDS PRODUCED DURING DRINKING WATER TREATMENT

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The Arsenic Rule under the Safe Drinking Water Act will require certain drinking water suppliers to add to or modify their existing treatment in order to comply with the regulations. One of the treatment options is iron co-precipitation. This treatment is attractive because ars...

Both Phosphorus Fertilizers and Indigenous Bacteria Enhance Arsenic Release into Groundwater in Arsenic-Contaminated Aquifers.

Science.gov (United States)

Lin, Tzu-Yu; Wei, Chia-Cheng; Huang, Chi-Wei; Chang, Chun-Han; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

2016-03-23

Arsenic (As) is a human carcinogen, and arsenic contamination in groundwater is a worldwide public health concern. Arsenic-affected areas are found in many places but are reported mostly in agricultural farmlands, yet the interaction of fertilizers, microorganisms, and arsenic mobilization in arsenic-contaminated aquifers remains uncharacterized. This study investigates the effects of fertilizers and bacteria on the mobilization of arsenic in two arsenic-contaminated aquifers. We performed microcosm experiments using arsenic-contaminated sediments and amended with inorganic nitrogenous or phosphorus fertilizers for 1 and 4 months under aerobic and anaerobic conditions. The results show that microcosms amended with 100 mg/L phosphorus fertilizers (dipotassium phosphate), but not nitrogenous fertilizers (ammonium sulfate), significantly increase aqueous As(III) release in arsenic-contaminated sediments under anaerobic condition. We also show that concentrations of iron, manganese, potassium, sodium, calcium, and magnesium are increased in the aqueous phase and that the addition of dipotassium phosphate causes a further increase in aqueous iron, potassium, and sodium, suggesting that multiple metal elements may take part in the arsenic release process. Furthermore, microbial analysis indicates that the dominant microbial phylum is shifted from α-proteobacteria to β- and γ-proteobacteria when the As(III) is increased and phosphate is added in the aquifer. Our results provide evidence that both phosphorus fertilizers and microorganisms can mediate the release of arsenic to groundwater in arsenic-contaminated sediments under anaerobic condition. Our study suggests that agricultural activity such as the use of fertilizers and monitoring phosphate concentration in groundwater should be taken into consideration for the management of arsenic in groundwater.

Rock-Bound Arsenic Influences Ground Water and Sediment Chemistry Throughout New England

Science.gov (United States)

Robinson, Gilpin R.; Ayotte, Joseph D.

2007-01-01

The information in this report was presented at the Northeastern Region Geological Society of America meeting held March 11-14, 2007, in Durham, New Hampshire. In the New England crystalline bedrock aquifer, concentrations of arsenic that exceed the drinking water standard of 10 ?g/L occur most frequently in ground water from wells sited in specific metamorphic and igneous rock units. Geochemical investigations indicate that these geologic units typically have moderately elevated whole-rock concentrations of arsenic compared to other rocks in the region. The distribution of ground water wells with As > 5 ?g/L has a strong spatial correlation with specific bedrock units where average whole-rock concentrations of arsenic exceed 1.1 mg/kg and where geologic and geochemical factors produce high pH ground water. Arsenic concentrations in stream sediments collected from small drainages reflect the regional distribution of this natural arsenic source and have a strong correlation with both rock chemistry and the distribution of bedrock units with elevated arsenic chemistry. The distribution of ground water wells with As > 5 ?g/L has a strong spatial correlation with the distribution of stream sediments where concentrations of arsenic exceed 6 mg/kg. Stream sediment chemistry also has a weak correlation with the distribution of agricultural lands where arsenical pesticides were used on apple, blueberry, and potato crops. Elevated arsenic concentrations in bedrock wells, however, do not correlate with agricultural areas where arsenical pesticides were used. These results indicate that both stream sediment chemistry and the solubility and mobility of arsenic in ground water in bedrock are influenced by host-rock arsenic concentrations. Stream sediment chemistry and the distribution of geologic units have been found to be useful parameters to predict the areas of greatest concern for elevated arsenic in ground water and to estimate the likely levels of human exposure to

Environmental source of arsenic exposure.

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Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

2014-09-01

Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

Environmental Source of Arsenic Exposure

Directory of Open Access Journals (Sweden)

Jin-Yong Chung

2014-09-01

Full Text Available Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

Assessing the Groundwater Concentrations and Geographical Distribution of Arsenic in Nepal

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Ma, J.; Liu, F.

2015-12-01

Arsenic 33As, one of the major groundwater contaminants, occurs in both natural and anthropogenic forms. Arsenic inhibits cellular respiration and the production of ATP in human body. Prolonged intake of non-lethal quantities of arsenic can cause cancer and diseases in vital organs such as the heart, liver, skin, and kidney. Each year, millions of people in the rural areas of Bangladesh, India, and other developing countries in South Asia are exposed to arsenic-poisoned groundwater. According to the World Health Organization, arsenic levels in drinking water should not exceed 10 parts per billion; however, the levels of arsenic found in groundwater in the heavily contaminated regions are often more than ten times of the recommended limit. Nepal is one of these regions. In most of the rural areas in Nepal, there is no infrastructure to produce clean filtered water, and wells thus became the major source. However, most of these wells were dug without testing for groundwater safety, because the test commands resources that the rural communities do not have access to. This is also limited data published on Nepal's groundwater contaminant levels. The scarcity of information prohibits the international community from recognizing the severity of arsenic poisoning in Nepal and coming up with the most efficient measures to help. With this project, we will present a method to determine groundwater safety by analyzing geologic data and using remote sensing. The original source of arsenic is the arsenic-bearing minerals in the sediments. Some geological formations have higher arsenic levels than others due to their depositional environments. Therefore, by using existing geologic data from Nepal and countries with similar types of arsenic contamination, we hope to determine correlations between areas where there are reports of high concentrations of arsenic in groundwater to the environmental factors that may cause a particular concentration of arsenic. Furthermore, with deeper

Urinary arsenic profile affects the risk of urothelial carcinoma even at low arsenic exposure

International Nuclear Information System (INIS)

Pu, Y.-S.; Yang, S.-M.; Huang, Y.-K.; Chung, C.-J.; Huang, Steven K.; Chiu, Allen Wen-Hsiang; Yang, M.-H.; Chen, C.-J.; Hsueh, Y.-M.

2007-01-01

Arsenic exposure is associated with an increased risk of urothelial carcinoma (UC). To explore the association between individual risk and urinary arsenic profile in subjects without evident exposure, 177 UC cases and 313 age-matched controls were recruited between September 2002 and May 2004 for a case-control study. Urinary arsenic species including the following three categories, inorganic arsenic (As III + As V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ), were determined with high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Arsenic methylation profile was assessed by percentages of various arsenic species in the sum of the three categories measured. The primary methylation index (PMI) was defined as the ratio between MMA V and inorganic arsenic. Secondary methylation index (SMI) was determined as the ratio between DMA V and MMA V . Smoking is associated with a significant risk of UC in a dose-dependent manner. After multivariate adjustment, UC cases had a significantly higher sum of all the urinary species measured, higher percent MMA V , lower percent DMA V , higher PMI and lower SMI values compared with controls. Smoking interacts with the urinary arsenic profile in modifying the UC risk. Differential carcinogenic effects of the urinary arsenic profile, however, were seen more prominently in non-smokers than in smokers, suggesting that smoking is not the only major environmental source of arsenic contamination since the UC risk differs in non-smokers. Subjects who have an unfavorable urinary arsenic profile have an increased UC risk even at low exposure levels

Cosmic-ray-produced stable nuclides: various production rates and their implications

International Nuclear Information System (INIS)

Reedy, R.C.

1981-01-01

The rates for a number of reactions producing certain stable nuclides, such as 3 He and 4 He, and fission in the moon are calculated for galactic-cosmic-ray particles and for solar protons. Solar-proton-induced reactions with bromine usually are not an important source of cosmogenic Kr isotopes. The 130 Ba(n,p) reaction cannot account for the undercalculation of 130 Xe production rates. Calculated production rates of 15 N, 13 C, and 2 H agree fairly well with rates inferred from measured excesses of these isotopes in samples with long exposure ages. Cosmic-ray-induced fission of U and Th can produce significant amounts of fission tracks and of 86 Kr, 134 Xe, and 136 Xe, especially in samples with long exposures to cosmic-ray particles

Pilot-scale demonstration of phytofiltration for treatment of arsenic in New Mexico drinking water.

Science.gov (United States)

Elless, Mark P; Poynton, Charissa Y; Willms, Cari A; Doyle, Mike P; Lopez, Alisa C; Sokkary, Dale A; Ferguson, Bruce W; Blaylock, Michael J

2005-10-01

Arsenic contamination of drinking water poses serious health risks to millions of people worldwide. To reduce such risks, the United States Environmental Protection Agency recently lowered the Maximum Contaminant Level for arsenic in drinking water from 50 to 10 microgL(-1). The majority of water systems requiring compliance are small systems that serve less than 10,000 people. Current technologies used to clean arsenic-contaminated water have significant drawbacks, particularly for small treatment systems. In this pilot-scale demonstration, we investigated the use of arsenic-hyperaccumulating ferns to remove arsenic from drinking water using a continuous flow phytofiltration system. Over the course of a 3-month demonstration period, the system consistently produced water having an arsenic concentration less than the detection limit of 2 microgL(-1), at flow rates as high as 1900 L day(-1) for a total treated water volume of approximately 60,000 L. Our results demonstrate that phytofiltration provides the basis for a solar-powered hydroponic technique to enable small-scale cleanup of arsenic-contaminated drinking water.

ARSENIC SPECIATION ANALYSIS IN HUMAN SALIVA

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Background: Determination of arsenic species in human saliva is potentially useful for biomonitoring of human exposure to arsenic and for studying arsenic metabolism. However, there is no report on the speciation analysis of arsenic in saliva. Methods: Arsenic species in saliva ...

Arsenic speciation in Chinese Herbal Medicines and human health implication for inorganic arsenic

International Nuclear Information System (INIS)

Liu Xiaojuan; Zhao Quanli; Sun Guoxin; Williams, Paul; Lu Xiujun; Cai Jingzhu; Liu Wenju

2013-01-01

Rice and drinking water are recognized as the dominant sources of arsenic (As) for human intake, while little is known about As accumulation and speciation in Chinese Herbal Medicines (CHMs), which have been available for many hundreds of years for the treatment of diseases in both eastern and western cultures. Inorganic arsenic was the predominant species in all of CHMs samples. The levels of inorganic arsenic in CHMs from fields and markets or pharmacies ranged from 63 to 550 ng/g with a mean of 208 ng/g and 94 to 8683 ng/g with a mean of 1092 ng/g, respectively. The highest concentration was found in the Chrysanthemum from pharmacies. It indicates that the risk of inorganic As in CHMs to human health is higher in medicines from markets or pharmacies than that collected directly from fields. Some CHMs may make a considerable contribution to the human intake of inorganic arsenic. - Highlights: ► Arsenic speciation was extracted using 1% HNO 3 in microwave. ► Inorganic arsenic was the predominant species in all of CHMs samples. ► The highest concentration of inorganic arsenic was found in the Chrysanthemum. - Inorganic arsenic was the predominant species in all of CHMs samples.

Dimethylthioarsinic anhydride: A standard for arsenic speciation

Energy Technology Data Exchange (ETDEWEB)

Fricke, Michael [United States Environmental Protection Agency, National Exposure Research Laboratory, Microbiological and Chemical Exposure Assessment Research Division, 26 W. Martin Luther King Drive, Cincinnati, OH 45268 (United States); Zeller, Matthias [STaRBURSTT-Cyberdiffraction Consortium, Department of Chemistry, Youngstown State University, One University Plaza, Youngstown, OH 44555-3663 (United States); Cullen, William [Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1 (Canada); Witkowski, Mark [Food and Drug Administration, Forensic Chemistry Center, Vibrational Spectroscopy Laboratory, 6751 Steger Drive, Cincinnati, OH 45237 (United States); Creed, John [United States Environmental Protection Agency, National Exposure Research Laboratory, Microbiological and Chemical Exposure Assessment Research Division, 26 W. Martin Luther King Drive, Cincinnati, OH 45268 (United States)]. E-mail: creed.jack@epa.gov

2007-01-30

Dimethylthioarsinic acid (DMTA{sup V}) has recently been identified in biological, dietary and environmental matrices. The relevance of this compound to the toxicity of arsenic in humans is unknown and further exposure assessment and metabolic studies are difficult to conduct because of the unavailability of a well characterized standard. The synthesis of DMTA{sup V} was accomplished by the reaction of dimethylarsinic acid (DMA{sup V}) with hydrogen sulfide. The initial reaction product produced is DMTA{sup V} but multiple products over the course of the reaction are also observed. Therefore, a chromatographic separation was developed to monitor the reaction progress via LC-ICP-MS. In this synthesis, conversion of DMA{sup V} to DMTA{sup V} was not taken to completion to avoid the production of side products. The product was isolated from the starting material by standard organic techniques. Single crystal diffraction demonstrated that solid DMTA{sup V} is present in the form of the oxygen-bridged dimethylthioarsinic anhydride. Dissolution of the anhydride in water produces the acid form of DMTA{sup V} and the aqueous phase DMTA{sup V} provided a characteristic molecular ion of m/z 155 by LC-ESI-MS. The synthesis and isolation of dimethylthioarsinic anhydride provides a stable crystalline standard suitable for identification, toxicological study and exposure assessment of dimethylthioarsinic acid.

Arsenic adsorption of lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil

Directory of Open Access Journals (Sweden)

Wuthiphun, L.

2007-05-01

Full Text Available Arsenic adsorption efficiency of soil covering materials (lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil obtained from Ronpiboon District, Nakhon Sri Thammarat Province tosolve arsenic air pollution problem was investigated using batch experiments. The four types of the aforementioned soil covering materials were examined to determine their arsenic adsorption efficiency, equilibriumtime as well as adsorption isotherms.The results revealed that among soil covering materials mixed with arsenic-contaminated soil at 10% w/w, the efficiency of arsenic adsorption of fly ash, lateritic soil, lime and limestone powder were 84, 60,38 and 1% respectively. The equilibrium time for lateritic soil at pH 4 was achieved within 4 hrs, whereas pH 7 and 12, the equilibrium time was 6 hrs. For fly ash, 2 hrs were required to reach the equilibrium at pH 12, while the equilibrium time was attained within 6 hrs at pH 4 and 7. Furthermore, lateritic soil possessedhigh arsenic adsorption efficiency at pH 7 and 4 and best fit with the Langmuir isotherm. The fly ash showing high arsenic adsorption efficiency at pH 12 and 7 fit the Freundlich isotherm at pH 12 and Langmuirisotherm at pH 7.This indicated that lateritic soil was suitable for arsenic adsorption at low pH, whilst at high pH,arsenic was well adsorbed by fly ash. The Freundlich and Langmuir isotherm could be used to determine quantities of soil covering materials for arsenic adsorption to prevent arsenic air pollution from arseniccontaminated soils.

The effects of arsenic or the combination of arsenic and radiation exposure is enhanced through the overexpression of the GSTO family member p28

International Nuclear Information System (INIS)

Giri, U.; Story, M.D.; Terry, N.H.A.; Giri, D.K.; Calkins, P.R.

2003-01-01

Full text: p28 is a member of the GST omega superfamily and has dehydroascorbate reductase, GST, and glutaredoxin activities. Furthermore, p28 is the rate-limiting enzyme in the bio-transformation of arsenic. The monomethyl arsenous reducatase activity of p28 produces dimethylarseniate, the most toxic form of arsenic. We investigated how p28 modulated arsenic cellular sensitivity in two mammalian models: 1) in LY-ar and LY-as cells where p28 is over-expressed and not expressed, respectively; and 2) in stably transfected A549 cells where p28 is over-expressed via a CMV promoter. The LY-ar mouse lymphoma cell line is radio and chemo-resistant and apoptosis refractory, whereas the parental cell line, LY-as, is radiosensitive and apoptotically permissive. In addition, we studied the effect of arsenic as a radiosensitizer in both cell systems. In LY-ar cells arsenic induced a dose- and time- dependent increase in apoptosis, which is comparable to that seen in LY-as cells. Arsenic plus 2.5Gy radiation induced apoptosis in LY-ar cells, which was more than additive. Survival in LY-ar cells was reduced to that of LY-as cells as well as p28 overexpression induced G2/M arrest in A549 cells and the combination of radiation with arsenic decreased the clonogenic survival of both the A549 and A549-p28 cells but the effect is more pronounced in the A549-P28 cell line. A549 and A549-p28 cells did not show a differential response to Taxol, which induces G2/M arrest and cell death via an inhibition of tubulin depolarization. Arsenic modulated the level of reduced GSH in both cell systems in a dose- and time- dependent manner, which correlated with survival outcome. This study illustrated that arsenic acts as a radiosensitizer and p28 augmented the potential of arsenic in inducing apoptosis, G2/M arrest, and radiosensitization. Further studies are underway to examine the bio-chemical pathways involved in arsenic-mediated cell death and the role of p28 therein

[Study on the variation of arsenic concentration in groundwater and chemical characteristics of arsenic in sediment cores at the areas with endemic arsenic poison disease in Jianghan Plain].

Science.gov (United States)

Zhou, Suhua; Ye, Hengpeng; Li, Mingjian; Xiong, Peisheng; Du, Dongyun; Wang, Jingwen

2015-06-01

To understand the variation of arsenic concentration in underground water at the endemic arsenic poison disease area of Jianghan Plain so as to better understand the spatial distribution of high arsenic groundwater, hydro-chemical evolution and source of arsenic in this region. Thirty underground water samples were collected respectively around 3 km radius of the two houses where arsenic poisoning patients lived, in Xiantao and Honghu. Sediment cores of three drillings were collected as well. Both paired t-test or paired Wilcoxon Signed Ranking Test were used to compare the arsenic concentration of water. The arsenic concentration in 2011-2012 appeared lower than that in 2006-2007 at the Nanhong village of Xiantao (t = 4.645 3, P arsenic concentration and Cl, HCO3(-), Fe, Mn. However, negative correlations were found between As and SO4(2-), NO3(-). The range of arsenic content in the sediment was 1.500 mg/kg to 17.289 mg/kg. The maximum arsenic content existed in the soil layer, while the minimum arsenic content existed in the sand layer. The concentration of arsenic varied widely with time and space at endemic arsenic poison disease area of Jianghan Plain. Characteristics of these water chemicals showed significant differences, when compared to the groundwater from Datong Basin, Shanxi Shanyin and Hetao Plain of Inner Mongolia, which presented a typical environment with high arsenic contents in the groundwater. The arsenic content in the sediment samples seemed related to the lithologic structure.

Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

International Nuclear Information System (INIS)

Hsieh, Yi-Chen; Lien, Li-Ming; Chung, Wen-Ting; Hsieh, Fang-I; Hsieh, Pei-Fan; Wu, Meei-Maan; Tseng, Hung-Pin; Chiou, Hung-Yi; Chen, Chien-Jen

2011-01-01

Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 μg/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 μg/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 μg/l). - Highlights: →Arsenic metabolic genes might be associated with carotid atherosclerosis. → A case

Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

Energy Technology Data Exchange (ETDEWEB)

Hsieh, Yi-Chen [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Lien, Li-Ming [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Neurology, Shin Kong WHS Memorial Hospital, Taipei, Taiwan (China); Chung, Wen-Ting [Department of Neurology, Wanfang Hospital, Taipei Medical University, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsieh, Fang-I; Hsieh, Pei-Fan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Wu, Meei-Maan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Graduate Institute of Basic Medicine, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan (China); Tseng, Hung-Pin [Department of Neurology, Lotung Poh-Ai Hospital, I-Lan, Taiwan (China); Chiou, Hung-Yi, E-mail: hychiou@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Chen, Chien-Jen [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China)

2011-08-15

Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 {mu}g/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 {mu}g/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 {mu}g/l). - Highlights: {yields}Arsenic metabolic genes might be associated with carotid atherosclerosis. {yields

Methylation of inorganic arsenic in different mammalian species and population groups.

Science.gov (United States)

Vahter, M

1999-01-01

Thousands of people in different parts of the world are exposed to arsenic via drinking water or contaminated soil or food. The high general toxic of arsenic has been known for centuries, and research during the last decades has shown that arsenic is a potent human carcinogen. However, most experimental cancer studies have failed to demonstrate carcinogenicity in experimental animals, indicating marked variation in sensitivity towards arsenic toxicity between species. It has also been suggested that there is a variation in susceptibility among human individuals. One reason for such variability in toxic response may be variation in metabolism. Inorganic arsenic is methylated in humans as well as animals and micro-organisms, but there are considerable differences between species and individuals. In many, but not all, mammalian species, inorganic arsenic is methylated to methylarsonic acid (MMA) and dimethylarsinic acid (DMA), which are more rapidly excreted in urine than is the inorganic arsenic, especially the trivalent form (AsIII, arsenite) which is highly reactive with tissue components. Absorbed arsenate (AsV) is reduced to trivalent arsenic (AsIII) before the methyl groups are attached. It has been estimated that as much as 50-70% of absorbed AsV is rapidly reduced to AsIII, a reaction which seems to be common for most species. In most experimental animal species, DMA is the main metabolite excreted in urine. Compared to human subjects, very little MMA is produced. However, the rate of methylation varies considerably between species, and several species, e.g. the marmoset monkey and the chimpanzee have been shown not to methylate inorganic arsenic at all. In addition, the marmoset monkey accumulates arsenic in the liver. The rat, on the other hand, has an efficient methylation of arsenic but the formed DMA is to a large extent accumulated in the red blood cells. As a result, the rat shows a low rate of excretion of arsenic. In both human subjects and rodents

A Phytoremediation Strategy for Arsenic

Energy Technology Data Exchange (ETDEWEB)

Meagher, Richard B.

2005-06-01

A Phytoremediation Strategy for Arsenic Progress Report May, 2005 Richard B. Meagher Principal Investigator Arsenic pollution affects the health of several hundred millions of people world wide, and an estimated 10 million Americans have unsafe levels of arsenic in their drinking water. However, few environmentally sound remedies for cleaning up arsenic contaminated soil and water have been proposed. Phytoremediation, the use of plants to extract and sequester environmental pollutants, is one new technology that offers an ecologically sound solution to a devastating problem. We propose that it is less disruptive to the environment to harvest and dispose of several thousand pounds per acre of contaminated aboveground plant material, than to excavate and dispose of 1 to 5 million pounds of contaminated soil per acre (assumes contamination runs 3 ft deep). Our objective is to develop a genetics-based phytoremediation strategy for arsenic removal that can be used in any plant species. This strategy requires the enhanced expression of several transgenes from diverse sources. Our working hypothesis is that organ-specific expression of several genes controlling the transport, electrochemical state, and binding of arsenic will result in the efficient extraction and hyperaccumulation of arsenic into aboveground plant tissues. This hypothesis is supported by theoretical arguments and strong preliminary data. We proposed six Specific Aims focused on testing and developing this arsenic phytoremediation strategy. During the first 18 months of the grant we made significant progress on five Specific Aims and began work on the sixth as summarized below. Specific Aim 1: Enhance plant arsenic resistance and greatly expand sinks for arsenite by expressing elevated levels of thiol-rich, arsenic-binding peptides. Hyperaccumulation of arsenic depends upon making plants that are both highly tolerant to arsenic and that have the capacity to store large amounts of arsenic aboveground

The effect of nanocrystalline magnetite size on arsenic removal

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J.T. Mayo et al

2007-01-01

Full Text Available Higher environmental standards have made the removal of arsenic from water an important problem for environmental engineering. Iron oxide is a particularly interesting sorbent to consider for this application. Its magnetic properties allow relatively routine dispersal and recovery of the adsorbent into and from groundwater or industrial processing facilities; in addition, iron oxide has strong and specific interactions with both As(III and As(V. Finally, this material can be produced with nanoscale dimensions, which enhance both its capacity and removal. The objective of this study is to evaluate the potential arsenic adsorption by nanoscale iron oxides, specifically magnetite (Fe3O4 nanoparticles. We focus on the effect of Fe3O4 particle size on the adsorption and desorption behavior of As(III and As(V. The results show that the nanoparticle size has a dramatic effect on the adsorption and desorption of arsenic. As particle size is decreased from 300 to 12 nm the adsorption capacities for both As(III and As(V increase nearly 200 times. Interestingly, such an increase is more than expected from simple considerations of surface area and suggests that nanoscale iron oxide materials sorb arsenic through different means than bulk systems. The desorption process, however, exhibits some hysteresis with the effect becoming more pronounced with small nanoparticles. This hysteresis most likely results from a higher arsenic affinity for Fe3O4 nanoparticles. This work suggests that Fe3O4 nanocrystals and magnetic separations offer a promising method for arsenic removal.

Effect of Arsenic on the Formation and Adsorption Property of Ferric Hydroxide Precipitates in ZVI Treatment

Energy Technology Data Exchange (ETDEWEB)

Peng, Xing; Xi, Beidou; Zhao, Ying; Shi, Qiantao; Meng, Xiaoguang; Mao, Xuhui; Jiang, Yonghai; Ma, Zhifei; Tan, Wenbing; Liu, Hongliang; Gong, Bin (Stevens); (Beijing NU); (CRAES); (Wuhan)

2017-08-14

Treatment of arsenic by zerovalent iron (ZVI) has been studied extensively. However, the effect of arsenic on the formation of ferric hydroxide precipitates in the ZVI treatment has not been investigated. We discovered that the specific surface area (ca. 187 m2/g) and arsenic content (ca. 67 mg/g) of the suspended solids (As-containing solids) generated in the ZVI treatment of arsenic solutions were much higher than the specific surface area (ca. 37 m2/g) and adsorption capacity (ca.12 mg/g) of the suspended solids (As-free solids) generated in the arsenic-free solutions. Arsenic in the As-containing solids was much more stable than the adsorbed arsenic in As-free solids. XRD, SEM, TEM, and selected area electron diffraction (SAED) analyses showed that the As-containing solids consisted of amorphous nanoparticles, while the As-free solids were composed of micron particles with weak crystallinity. Extended X-ray absorption fine structure (EXAFS) analysis determined that As(V) was adsorbed on the As-containing suspended solids and magnetic solid surfaces through bidentate binuclear complexation; and As(V) formed a mononuclear complex on the As-free suspended solids. The formation of the surface As(V) complexes retarded the bonding of free FeO6 octahedra to the oxygen sites on FeO6 octahedral clusters and prevented the growth of the clusters and their development into 3-dimensional crystalline phases.

Arsenic concentrations in Chinese coals

International Nuclear Information System (INIS)

Wang Mingshi; Zheng Baoshan; Wang Binbin; Li Shehong; Wu Daishe; Hu Jun

2006-01-01

The arsenic concentrations in 297 coal samples were collected from the main coal-mines of 26 provinces in China were determined by molybdenum blue coloration method. These samples were collected from coals that vary widely in coal rank and coal-forming periods from the five main coal-bearing regions in China. Arsenic content in Chinese coals range between 0.24 to 71 mg/kg. The mean of the concentration of Arsenic is 6.4 ± 0.5 mg/kg and the geometric mean is 4.0 ± 8.5 mg/kg. The level of arsenic in China is higher in northeastern and southern provinces, but lower in northwestern provinces. The relationship between arsenic content and coal-forming period, coal rank is studied. It was observed that the arsenic contents decreases with coal rank in the order: Tertiary > Early Jurassic > Late Triassic > Late Jurassic > Middle Jurassic > Late Permian > Early Carboniferous > Middle Carboniferous > Late Carboniferous > Early Permian; It was also noted that the arsenic contents decrease in the order: Subbituminous > Anthracite > Bituminous. However, compared with the geological characteristics of coal forming region, coal rank and coal-forming period have little effect on the concentration of arsenic in Chinese coal. The average arsenic concentration of Chinese coal is lower than that of the whole world. The health problems in China derived from in coal (arsenism) are due largely to poor local life-style practices in cooking and home heating with coal rather than to high arsenic contents in the coal

Arsenic responsive microRNAs in vivo and their potential involvement in arsenic-induced oxidative stress

International Nuclear Information System (INIS)

Ren, Xuefeng; Gaile, Daniel P.; Gong, Zhihong; Qiu, Wenting; Ge, Yichen; Zhang, Chuanwu; Huang, Chenping; Yan, Hongtao; Olson, James R.; Kavanagh, Terrance J.; Wu, Hongmei

2015-01-01

Arsenic exposure is postulated to modify microRNA (miRNA) expression, leading to changes of gene expression and toxicities, but studies relating the responses of miRNAs to arsenic exposure are lacking, especially with respect to in vivo studies. We utilized high-throughput sequencing technology and generated miRNA expression profiles of liver tissues from Sprague Dawley (SD) rats exposed to various concentrations of sodium arsenite (0, 0.1, 1, 10 and 100 mg/L) for 60 days. Unsupervised hierarchical clustering analysis of the miRNA expression profiles clustered the SD rats into different groups based on the arsenic exposure status, indicating a highly significant association between arsenic exposure and cluster membership (p-value of 0.0012). Multiple miRNA expressions were altered by arsenic in an exposure concentration-dependent manner. Among the identified arsenic-responsive miRNAs, several are predicted to target Nfe2l2-regulated antioxidant genes, including glutamate–cysteine ligase (GCL) catalytic subunit (GCLC) and modifier subunit (GCLM) which are involved in glutathione (GSH) synthesis. Exposure to low concentrations of arsenic increased mRNA expression for Gclc and Gclm, while high concentrations significantly reduced their expression, which were correlated to changes in hepatic GCL activity and GSH level. Moreover, our data suggested that other mechanisms, e.g., miRNAs, rather than Nfe2l2-signaling pathway, could be involved in the regulation of mRNA expression of Gclc and Gclm post-arsenic exposure in vivo. Together, our findings show that arsenic exposure disrupts the genome-wide expression of miRNAs in vivo, which could lead to the biological consequence, such as an altered balance of antioxidant defense and oxidative stress. - Highlights: • Chronic arsenic exposure induces changes of hepatic miRNA expression profiles. • Hepatic GCL activity and GSH level in rats are altered following arsenic exposure. • Arsenic induced GCL expression change is

Arsenic responsive microRNAs in vivo and their potential involvement in arsenic-induced oxidative stress

Energy Technology Data Exchange (ETDEWEB)

Ren, Xuefeng, E-mail: xuefengr@buffalo.edu [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Department of Pharmacology and Toxicology, School of Biomedical Sciences, The State University of New York, Buffalo, NY 14214 (United States); Gaile, Daniel P. [Department of Biostatistics, School of Public Health and Health Professions, the State University of New York, Buffalo, NY 14214 (United States); Gong, Zhihong [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Qiu, Wenting [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Ge, Yichen [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Zhang, Chuanwu; Huang, Chenping; Yan, Hongtao [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Olson, James R. [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Department of Pharmacology and Toxicology, School of Biomedical Sciences, The State University of New York, Buffalo, NY 14214 (United States); Kavanagh, Terrance J. [Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195 (United States); Wu, Hongmei, E-mail: hongmeiwwu@hotmail.com [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China)

2015-03-15

Arsenic exposure is postulated to modify microRNA (miRNA) expression, leading to changes of gene expression and toxicities, but studies relating the responses of miRNAs to arsenic exposure are lacking, especially with respect to in vivo studies. We utilized high-throughput sequencing technology and generated miRNA expression profiles of liver tissues from Sprague Dawley (SD) rats exposed to various concentrations of sodium arsenite (0, 0.1, 1, 10 and 100 mg/L) for 60 days. Unsupervised hierarchical clustering analysis of the miRNA expression profiles clustered the SD rats into different groups based on the arsenic exposure status, indicating a highly significant association between arsenic exposure and cluster membership (p-value of 0.0012). Multiple miRNA expressions were altered by arsenic in an exposure concentration-dependent manner. Among the identified arsenic-responsive miRNAs, several are predicted to target Nfe2l2-regulated antioxidant genes, including glutamate–cysteine ligase (GCL) catalytic subunit (GCLC) and modifier subunit (GCLM) which are involved in glutathione (GSH) synthesis. Exposure to low concentrations of arsenic increased mRNA expression for Gclc and Gclm, while high concentrations significantly reduced their expression, which were correlated to changes in hepatic GCL activity and GSH level. Moreover, our data suggested that other mechanisms, e.g., miRNAs, rather than Nfe2l2-signaling pathway, could be involved in the regulation of mRNA expression of Gclc and Gclm post-arsenic exposure in vivo. Together, our findings show that arsenic exposure disrupts the genome-wide expression of miRNAs in vivo, which could lead to the biological consequence, such as an altered balance of antioxidant defense and oxidative stress. - Highlights: • Chronic arsenic exposure induces changes of hepatic miRNA expression profiles. • Hepatic GCL activity and GSH level in rats are altered following arsenic exposure. • Arsenic induced GCL expression change is

Natural Arsenic Pollution and Hydrochemistry of Drinking Water of an Urban Part of Iran

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Mohammad Mosaferi

2014-12-01

Full Text Available Natural contamination of surface and groundwater resources with arsenic is a worldwide problem. The present study aimed to investigate and report on the quality of drinking water resources with special focus on arsenic presence in an urban part of Iran. Arsenic concentrations were measured by graphite furnace atomic absorption spectroscopy (GFAAS. In both surface and groundwater samples, arsenic concentrations ranged from 6 - 61 µg/L with an average value of 39 ± 20 µg/L. Concentration of arsenic, which was up to six times greater than guideline values (10 µg/L indicates the presence of arsenic bearing materials in the geological structure of the region. It was found that the quality of treated surface water produced by the water treatment facility was good in respect to arsenic (9 µg/L and solid content (EC = µs/cm. However, in drinking water samples of wells, total solids (mean EC = 1580 ± 150 µs/cm, total hardness (mean = 479 + 94 mg/L as CaCO3 and arsenic (mean = 42 + 16 µg/L were significantly higher. Correspondingly, there was a significant correlation between arsenic concentration and EC, Na+, K+ and Cl- values. The type of water in most of groundwater samples (70% was determined as HCO3-Na+. Considering the population of the city and probable health effects due to exposure to arsenic through drinking water, comprehensive measures as well as application of arsenic removal processes in water treatment facilities and replacement of contaminated wells with safe wells are required.

Performance of a New Magnetic Chitosan Nanoparticle to Remove Arsenic and Its Separation from Water

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Cheng Liu

2015-01-01

Full Text Available Removal performance of arsenic in water by a novel magnetic chitosan nanoparticle (MCNP with a diameter of about 10 nm, including adsorption kinetics, adsorption isotherm, main influencing factors, and regeneration effects, was investigated. In addition, the effective separation way for MCNP particles and the new application mode were developed to prompt the application of MCNP. The results showed that MCNP exhibited excellent ability to remove As(V and As(III from water in a wide range of initial concentrations, MCNP removed arsenic rapidly with more than 95% of arsenic adsorbed in initial 15 min, and the whole process fitted well to the pseudo-second-order model. The Langmuir model fits the equilibrium data better than the Freundlich isotherm model and the maximum adsorption capacities of As(V and As(III were 65.5 mg/g and 60.2 mg/g, respectively. The saturated MCNP could be easily regenerated and kept more than 95% of initial adsorption capacity stable after 10 regeneration cycles. A new magnetic material separation method was established to separate MCNP effectively. The continuous-operation instrument developed based on the MCNP could operate stably and guarantee that the concentration of arsenic meets the guideline limit of arsenic in drinking water regulated by the WHO.

INORGANIC ARSENIC SPECIATION IN THE ATMOSPHERE: STUDY IN ISFAHAN

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A KALANTARI

2000-06-01

Full Text Available Introduction. Arsenic is one of the most hazardous elements that associate with airborne particulate matter in the atmosphere. Among the different species of arsenic, ASIII has the most toxic and carcinogenic property between any other kind of this element. Arsenic speciation is important in environmental studies. Methods. We collected 59 samples of airborne particulate matter from the atmosphere in Isfahan in a three months period by a high volume air sampler with a flow rate of 1 m3 min-1. Air particulates were collected on the paper filter (Whatman No.41. Four different digestive procedures were examined in order to find the best method. At last we chose digestion of filter with HCI (10-4N due to its feasibility, cost benefit and efficacy. Other methods that examined were digestion of filter with a mixture of HN03 and H2O2, with a mixture of HNO3 and H2O2 and with HCI (1 N. The determination of As3+ and As5+ concentrations were performed by hydrIde generation atomic absorption spectrometry. The effect of Ph on the absorption signal was also investigated in arsenic speciation. Results. Average of total saspended particles (TSP in July, August, and September 1998 were 223, 172, and 247 mg.m3 respectively. The recovery of arsenic from airborne particulate matter was almost the same for the different digestion methods. The concentration and volume of NaBH4 was optimized for determining of different species of arsenic. At pH=5, Asv didn't produce any absorption signal. So, the determination of ASm was carried out easilyat the above mentioned pH. The concentrations of total arsenic were determined in 47 samples. The mean concentrations of total arsenic in July, August and September were 3.31, 2.01 and 2.6, respectively. Discussion. More than 50 percent of total atmospheric arsenic exists as ASIII which is the most toxic and carcinogenic forms of this element. So, it is recommended to make a suitable policy for decreasing of this hazardous

Determination of total arsenic in soil and arsenic-resistant bacteria from selected ground water in Kandal Province, Cambodia

International Nuclear Information System (INIS)

Hamzah, A.; Wong, K.K.; Hasan, F.N.; Mustafa, S.; Khoo, K.S.; Sarmani, S.B.

2013-01-01

Cambodia has geological environments conducive to generation of high-arsenic groundwater and people are at high risk of chronic arsenic exposure. The aims of this study are to investigate the concentration of total arsenic and to isolate and identify arsenic-resistant bacteria from selected locations in Kandal Province, Cambodia. The INAA technique was used to measure the concentration of total arsenic in soils. The arsenic concentrations in soils were above permissible 5 mg/kg, ranging from 5.34 to 27.81 mg/kg. Bacteria resistant to arsenic from two arsenic-contaminated wells in Preak Russey were isolated by enrichment method in nutrient broth (NB). Colonies isolated from NB was then grown on minimal salt media (MSM) added with arsenic at increasing concentrations of 10, 20, 30, 50, 100 and 250 ppm. Two isolates that can tolerate 750 ppm of arsenic were identified as Enterobacter agglomerans and Acinetobacter lwoffii based on a series of biochemical, physiological and morphological analysis. Optimum growth of both isolates ranged from pH 6.6 to 7.0 and 30-35 deg C. E. agglomerans and A. lwoffii were able to remove 66.4 and 64.1 % of arsenic, respectively at the initial concentration of 750 ppm, within 72 h of incubation. Using energy dispersive X-ray technique, the percentage of arsenic absorbed by E. agglomerans and A. lwoffii was 0.09 and 0.15 %, respectively. This study suggested that arsenic-resistant E. agglomerans and A. lwoffii removed arsenic from media due to their ability to absorb arsenic. (author)

Superior removal of arsenic from water with zirconium metal-organic framework UiO-66

Science.gov (United States)

Wang, Chenghong; Liu, Xinlei; Chen, J. Paul; Li, Kang

2015-01-01

In this study, water stable zirconium metal-organic framework (UiO-66) has been synthesized and for the first time applied as an adsorbent to remove aquatic arsenic contamination. The as-synthesized UiO-66 adsorbent functions excellently across a broad pH range of 1 to 10, and achieves a remarkable arsenate uptake capacity of 303 mg/g at the optimal pH, i.e., pH = 2. To the best of our knowledge, this is the highest arsenate As(V) adsorption capacity ever reported, much higher than that of currently available adsorbents (5–280 mg/g, generally less than 100 mg/g). The superior arsenic uptake performance of UiO-66 adsorbent could be attributed to the highly porous crystalline structure containing zirconium oxide clusters, which provides a large contact area and plenty of active sites in unit space. Two binding sites within the adsorbent framework are proposed for arsenic species, i.e., hydroxyl group and benzenedicarboxylate ligand. At equilibrium, seven equivalent arsenic species can be captured by one Zr6 cluster through the formation of Zr-O-As coordination bonds. PMID:26559001

Superior removal of arsenic from water with zirconium metal-organic framework UiO-66.

Science.gov (United States)

Wang, Chenghong; Liu, Xinlei; Chen, J Paul; Li, Kang

2015-11-12

In this study, water stable zirconium metal-organic framework (UiO-66) has been synthesized and for the first time applied as an adsorbent to remove aquatic arsenic contamination. The as-synthesized UiO-66 adsorbent functions excellently across a broad pH range of 1 to 10, and achieves a remarkable arsenate uptake capacity of 303 mg/g at the optimal pH, i.e., pH = 2. To the best of our knowledge, this is the highest arsenate As(V) adsorption capacity ever reported, much higher than that of currently available adsorbents (5-280 mg/g, generally less than 100 mg/g). The superior arsenic uptake performance of UiO-66 adsorbent could be attributed to the highly porous crystalline structure containing zirconium oxide clusters, which provides a large contact area and plenty of active sites in unit space. Two binding sites within the adsorbent framework are proposed for arsenic species, i.e., hydroxyl group and benzenedicarboxylate ligand. At equilibrium, seven equivalent arsenic species can be captured by one Zr6 cluster through the formation of Zr-O-As coordination bonds.

Effects of water chemistry on arsenic removal from drinking water by electrocoagulation.

Science.gov (United States)

Wan, Wei; Pepping, Troy J; Banerji, Tuhin; Chaudhari, Sanjeev; Giammar, Daniel E

2011-01-01

Exposure to arsenic through drinking water poses a threat to human health. Electrocoagulation is a water treatment technology that involves electrolytic oxidation of anode materials and in-situ generation of coagulant. The electrochemical generation of coagulant is an alternative to using chemical coagulants, and the process can also oxidize As(III) to As(V). Batch electrocoagulation experiments were performed in the laboratory using iron electrodes. The experiments quantified the effects of pH, initial arsenic concentration and oxidation state, and concentrations of dissolved phosphate, silica and sulfate on the rate and extent of arsenic removal. The iron generated during electrocoagulation precipitated as lepidocrocite (γ-FeOOH), except when dissolved silica was present, and arsenic was removed by adsorption to the lepidocrocite. Arsenic removal was slower at higher pH. When solutions initially contained As(III), a portion of the As(III) was oxidized to As(V) during electrocoagulation. As(V) removal was faster than As(III) removal. The presence of 1 and 4 mg/L phosphate inhibited arsenic removal, while the presence of 5 and 20 mg/L silica or 10 and 50 mg/L sulfate had no significant effect on arsenic removal. For most conditions examined in this study, over 99.9% arsenic removal efficiency was achieved. Electrocoagulation was also highly effective at removing arsenic from drinking water in field trials conducted in a village in Eastern India. By using operation times long enough to produce sufficient iron oxide for removal of both phosphate and arsenate, the performance of the systems in field trials was not inhibited by high phosphate concentrations. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Arsenical keratosis treated by dermatome shaving].

Science.gov (United States)

Kjerkegaard, Ulrik Knap; Heje, Jens Martin; Vestergaard, Christian; Stausbøl-Grøn, Birgitte; Stolle, Lars Bjørn

2014-05-05

Cutaneous malignancy in association with arsenic exposure is a rare but well-documented phenomenon. Signs of chronic arsenic exposure are very rare in Denmark today. However, arsenic was used in the medical treatment of psoriasis vulgaris up till the 1980's and several patients suffer from this arsenic treatment today. This case report shows that arsenical keratosis can be treated by dermatome shaving, a superficial destructive therapy.

Arsenic exposure disrupts epigenetic regulation of SIRT1 in human keratinocytes

Energy Technology Data Exchange (ETDEWEB)

Herbert, Katharine J. [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia); Holloway, Adele [Menzies Research Institute Tasmania, University of Tasmania, Hobart, TAS 7000 (Australia); Cook, Anthony L. [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia); Chin, Suyin P. [Menzies Research Institute Tasmania, University of Tasmania, Hobart, TAS 7000 (Australia); Snow, Elizabeth T., E-mail: elizabeth.snow@utas.edu.au [School of Health Sciences, University of Tasmania, Launceston, TAS 7250 (Australia)

2014-11-15

Arsenic is an environmental toxin which increases skin cancer risk for exposed populations worldwide; however the underlying biomolecular mechanism for arsenic-induced carcinogenesis is complex and poorly defined. Recent investigations show that histone deacetylase and DNA methyltransferase activity is impaired, and epigenetic patterns of gene regulation are consistently altered in cancers associated with arsenic exposure. Expression of the histone deacetylase SIRT1 is altered in solid tumours and haematological malignancies; however its role in arsenic-induced pathology is unknown. In this study we investigated the effect of arsenic on epigenetic regulation of SIRT1 and its targeting microRNA, miR-34a in primary human keratinocytes. Acetylation of histone H4 at lysine 16 (H4K16) increased in keratinocytes exposed to 0.5 μM arsenite [As(III)]; and this was associated with chromatin remodelling at the miR-34a promoter. Moreover, although SIRT1 protein initially increased in these As(III)-exposed cells, after 24 days expression was not significantly different from untreated controls. Extended exposure to low-dose As(III) (0.5 μM; > 5 weeks) compromised the pattern of CpG methylation at SIRT1 and miR-34a gene promoters, and this was associated with altered expression for both genes. We have found that arsenic alters epigenetic regulation of SIRT1 expression via structural reorganisation of chromatin at the miR-34a gene promoter in the initial 24 h of exposure; and over time, through shifts in miR-34a and SIRT1 gene methylation. Taken together, this investigation demonstrates that arsenic produces cumulative disruptions to epigenetic regulation of miR-34a expression, and this is associated with impaired coordination of SIRT1 functional activity. - Highlights: • Submicromolar arsenic concentrations disrupt SIRT1 activity and expression in human keratinocytes. • Arsenic-induced chromatin remodelling at the miR-34a gene promoter is associated with hyperacetylation

Arsenic exposure disrupts epigenetic regulation of SIRT1 in human keratinocytes

International Nuclear Information System (INIS)

Herbert, Katharine J.; Holloway, Adele; Cook, Anthony L.; Chin, Suyin P.; Snow, Elizabeth T.

2014-01-01

Arsenic is an environmental toxin which increases skin cancer risk for exposed populations worldwide; however the underlying biomolecular mechanism for arsenic-induced carcinogenesis is complex and poorly defined. Recent investigations show that histone deacetylase and DNA methyltransferase activity is impaired, and epigenetic patterns of gene regulation are consistently altered in cancers associated with arsenic exposure. Expression of the histone deacetylase SIRT1 is altered in solid tumours and haematological malignancies; however its role in arsenic-induced pathology is unknown. In this study we investigated the effect of arsenic on epigenetic regulation of SIRT1 and its targeting microRNA, miR-34a in primary human keratinocytes. Acetylation of histone H4 at lysine 16 (H4K16) increased in keratinocytes exposed to 0.5 μM arsenite [As(III)]; and this was associated with chromatin remodelling at the miR-34a promoter. Moreover, although SIRT1 protein initially increased in these As(III)-exposed cells, after 24 days expression was not significantly different from untreated controls. Extended exposure to low-dose As(III) (0.5 μM; > 5 weeks) compromised the pattern of CpG methylation at SIRT1 and miR-34a gene promoters, and this was associated with altered expression for both genes. We have found that arsenic alters epigenetic regulation of SIRT1 expression via structural reorganisation of chromatin at the miR-34a gene promoter in the initial 24 h of exposure; and over time, through shifts in miR-34a and SIRT1 gene methylation. Taken together, this investigation demonstrates that arsenic produces cumulative disruptions to epigenetic regulation of miR-34a expression, and this is associated with impaired coordination of SIRT1 functional activity. - Highlights: • Submicromolar arsenic concentrations disrupt SIRT1 activity and expression in human keratinocytes. • Arsenic-induced chromatin remodelling at the miR-34a gene promoter is associated with hyperacetylation

Effects of arsenic on nitrate metabolism in arsenic hyperaccumulating and non-hyperaccumulating ferns

Energy Technology Data Exchange (ETDEWEB)

Singh, Nandita [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India); Ma, Lena Q., E-mail: lqma@ufl.ed [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Vu, Joseph C. [Chemistry Research Unit, CMAVE, USDA-ARS, Gainesville, FL 32608-1069 and Agronomy Department, University of Florida, Gainesville, FL 32611-0500 (United States); Raj, Anshita [Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India)

2009-08-15

This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of four-month old Pteris vittata (arsenic - hyperaccumulator) and Pteris ensiformis (non-arsenic--hyperaccumulator) plants. The arsenic treatments (0, 150, and 300 muM as sodium arsenate) in hydroponics had adverse effects on the root and frond dry weights, and this effect was more evident in P. ensiformis than in P. vittata. Nitrate reductase and nitrite reductase activities of arsenate-treated plants were reduced more in P. ensiformis than in P. vittata. This effect was accompanied by similar decreases in tissue NO{sub 3}{sup -} concentrations. Therefore, this decrease is interpreted as being indirect, i.e., the consequence of the reduced NO{sub 3}{sup -} uptake and translocation in the plants. The study shows the difference in the tolerance level of the two Pteris species with varying sensitivity to arsenic. - Arsenic reduced the activity of nitrate and nitrite reductase more in Pteris ensiformis than Pteris vittata.

Arsenic speciation in shrimp and mussel from the Mid-Atlantic hydrothermal vents

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Quetel, C. R.; Munoz, R.

1997-01-01

Specimens of shrimp (Rimicaris exoculata) and mussel (Bathymodiolus puteoserpentis) were collected 3500 m below the ocean surface at the hydrothermal vents of the mid-Atlantic Ridge (TAG and Snake Pit sites, respectively). Arsenic, a potentially toxic element, is among the substances emitted...... by the hydrothermal vents. The hydrothermal vent shrimp, which are known to be a primary consumer of the primary producing chemolithoautotrophic bacteria, contained arsenic at 13 mu g g(-1) almost exclusively as arsenobetaine (AsB). Arsenic was present in the soft:issues of the mussel at 40 mu g g(-1) and the major...... of arsenic species found in the shrimp and mussel species in the deep-sea is similar to that found in their counterparts from the ocean surface. It is concluded that the autotrophic bacteria of the hydrothermal vent ecosystem and the symbiotic bacteria harboured in the mussel species are responsible...

Design of a rural water provision system to decrease arsenic exposure in Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Mathieu, Johanna [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2009-01-09

Researchers at the Lawrence Berkeley National Laboratory have invented ARUBA (Arsenic Removal Using Bottom Ash) a material that effectively and affordably removes high concentrations of arsenic from contaminated groundwater. The technology is cost-effective because the substrate-bottom ash from coal fired power plants-is a waste material readily available in South Asia. During fieldwork in four sub-districts of Bangladesh, ARUBA reduced groundwater arsenic concentrations as high as 680 ppb to below the Bangladesh standard of 50 ppb. Key results from three trips in Bangladesh and one trip to Cambodia include (1) ARUBA removes more than half of the arsenic from contaminated water within the first five minutes of contact, and continues removing arsenic for 2-3 days; (2) ARUBA's arsenic removal efficiency can be improved through fractionated dosing (adding a given amount of ARUBA in fractions versus all at once); (3) allowing water to first stand for two to three days followed by treatment with ARUBA produced final arsenic concentrations ten times lower than treating water directly out of the well; and (4) the amount of arsenic removed per gram of ARUBA is linearly related to the initial arsenic concentration of the water. Through analysis of existing studies, observations, and informal interviews in Bangladesh, eight design strategies have been developed and used in the design of a low-cost, community-scale water treatment system that uses ARUBA to remove arsenic from drinking water. We have constructed, tested, and analyzed a scale version of the system. Experiments have shown that the system is capable of reducing high levels of arsenic (nearly 600 ppb) to below 50 ppb, while remaining affordable to people living on less than $2 per day. The system could be sustainably implemented as a public-private partnership in rural Bangladesh.

Arsenic Exposure, Arsenic Metabolism, and Incident Diabetes in the Strong Heart Study

Science.gov (United States)

Howard, Barbara V.; Umans, Jason G.; Gribble, Matthew O.; Best, Lyle G.; Francesconi, Kevin A.; Goessler, Walter; Lee, Elisa; Guallar, Eliseo; Navas-Acien, Ana

2015-01-01

OBJECTIVE Little is known about arsenic metabolism in diabetes development. We investigated the prospective associations of low-moderate arsenic exposure and arsenic metabolism with diabetes incidence in the Strong Heart Study. RESEARCH DESIGN AND METHODS A total of 1,694 diabetes-free participants aged 45–75 years were recruited in 1989–1991 and followed through 1998–1999. We used the proportions of urine inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) over their sum (expressed as iAs%, MMA%, and DMA%) as the biomarkers of arsenic metabolism. Diabetes was defined as fasting glucose ≥126 mg/dL, 2-h glucose ≥200 mg/dL, self-reported diabetes history, or self-reported use of antidiabetic medications. RESULTS Over 11,263.2 person-years of follow-up, 396 participants developed diabetes. Using the leave-one-out approach to model the dynamics of arsenic metabolism, we found that lower MMA% was associated with higher diabetes incidence. The hazard ratios (95% CI) of diabetes incidence for a 5% increase in MMA% were 0.77 (0.63–0.93) and 0.82 (0.73–0.92) when iAs% and DMA%, respectively, were left out of the model. DMA% was associated with higher diabetes incidence only when MMA% decreased (left out of the model) but not when iAs% decreased. iAs% was also associated with higher diabetes incidence when MMA% decreased. The association between MMA% and diabetes incidence was similar by age, sex, study site, obesity, and urine iAs concentrations. CONCLUSIONS Arsenic metabolism, particularly lower MMA%, was prospectively associated with increased incidence of diabetes. Research is needed to evaluate whether arsenic metabolism is related to diabetes incidence per se or through its close connections with one-carbon metabolism. PMID:25583752

The future of producing separated stable isotopes at Oak Ridge National Laboratory for accelerator applications

International Nuclear Information System (INIS)

Collins, E.D.

1994-01-01

Separated stable isotopes, produced in the calutrons at Oak Ridge National Laboratory, are essential target materials for production of numerous radioisotopes in accelerators and reactors. Recently, separated stable isotope production has been curtailed because government appropriations were discontinued and salts revenues decreased. The calutrons were placed in standby and the operating staff reduced to enable support by sales from existing inventories. Appeals were made to industry and government to preserve this national capability. Methods for providing volume-based price reductions were created to attract support from commercial isotope users. In 1994, the Department of Energy's Isotope Production and Distribution Program was restructured and a strategy produced to seek appropriated funding for the future production of rare, nonprofitable isotopes for research uses. This strategy, together with new demands for medical isotopes, will enable future operation of the calutrons. Moreover, production may be enhanced by complementing calutron capabilities with the Plasma Separation Process

Acute and chronic arsenic toxicity

OpenAIRE

Ratnaike, R

2003-01-01

Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption o...

Stable groundwater quality in deep aquifers of Southern Bangladesh: The case against sustainable abstraction

International Nuclear Information System (INIS)

Ravenscroft, P.; McArthur, J.M.; Hoque, M.A.

2013-01-01

In forty six wells > 150 m deep, from across the arsenic-polluted area of south-central Bangladesh, groundwater composition remained unchanged between 1998 and 2011. No evidence of deteriorating water quality was found in terms of arsenic, iron, manganese, boron, barium or salinity over this period of 13 years. These deep tubewells have achieved operating lives of more than 20 years with minimal institutional support. These findings confirm that tubewells tapping the deep aquifers in the Bengal Basin provide a safe, popular, and economic, means of arsenic mitigation and are likely to do so for decades to come. Nevertheless, concerns remain about the sustainability of a resource that could serve as a source of As-safe water to mitigate As-pollution in shallower aquifers in an area where tens of millions of people are exposed to dangerous levels of arsenic in well water. The conjunction of the stable composition in deep groundwater and the severe adverse health effects of arsenic in shallow groundwater lead us to challenge the notion that strong sustainability principles should be applied to the management of deep aquifer abstraction in Bangladesh is, the notion that the deep groundwater resource should be preserved for future generations by protecting it from adverse impacts, probably of a minor nature, that could occur after a long time and might not happen at all. Instead, we advocate an ethical approach to development of the deep aquifer, based on adaptive abstraction management, which allows possibly unsustainable exploitation now in order to alleviate crippling disease and death from arsenic today while also benefiting future generations by improving the health, education and economy of living children. - Highlights: • Tens of millions of people in Bangladesh are affected by arsenic pollution of groundwater. • Deep wells in potentially non-renewable aquifers are the dominant form of mitigation. • Water quality in these aquifers has remained stable for 13

Stable groundwater quality in deep aquifers of Southern Bangladesh: The case against sustainable abstraction

Energy Technology Data Exchange (ETDEWEB)

Ravenscroft, P., E-mail: pravenscroft@unicef.org [UNICEF, BSL Office Complex, Minto Road, Dhaka 1000 (Bangladesh); McArthur, J.M.; Hoque, M.A. [Earth Sciences, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2013-06-01

In forty six wells > 150 m deep, from across the arsenic-polluted area of south-central Bangladesh, groundwater composition remained unchanged between 1998 and 2011. No evidence of deteriorating water quality was found in terms of arsenic, iron, manganese, boron, barium or salinity over this period of 13 years. These deep tubewells have achieved operating lives of more than 20 years with minimal institutional support. These findings confirm that tubewells tapping the deep aquifers in the Bengal Basin provide a safe, popular, and economic, means of arsenic mitigation and are likely to do so for decades to come. Nevertheless, concerns remain about the sustainability of a resource that could serve as a source of As-safe water to mitigate As-pollution in shallower aquifers in an area where tens of millions of people are exposed to dangerous levels of arsenic in well water. The conjunction of the stable composition in deep groundwater and the severe adverse health effects of arsenic in shallow groundwater lead us to challenge the notion that strong sustainability principles should be applied to the management of deep aquifer abstraction in Bangladesh is, the notion that the deep groundwater resource should be preserved for future generations by protecting it from adverse impacts, probably of a minor nature, that could occur after a long time and might not happen at all. Instead, we advocate an ethical approach to development of the deep aquifer, based on adaptive abstraction management, which allows possibly unsustainable exploitation now in order to alleviate crippling disease and death from arsenic today while also benefiting future generations by improving the health, education and economy of living children. - Highlights: • Tens of millions of people in Bangladesh are affected by arsenic pollution of groundwater. • Deep wells in potentially non-renewable aquifers are the dominant form of mitigation. • Water quality in these aquifers has remained stable for 13

AS3MT-mediated tolerance to arsenic evolved by multiple independent horizontal gene transfers from bacteria to eukaryotes

DEFF Research Database (Denmark)

Palmgren, Michael; Engström, Karin; Hallström, Björn M.

2017-01-01

the evolutionary origin of AS3MT and assessed the ability of different genotypes to produce methylated arsenic metabolites. Phylogenetic analysis suggests that multiple, independent horizontal gene transfers between different bacteria, and from bacteria to eukaryotes, increased tolerance to environmental arsenic...

Arsenic metabolism efficiency has a causal role in arsenic toxicity: Mendelian randomization and gene-environment interaction.

Science.gov (United States)

Pierce, Brandon L; Tong, Lin; Argos, Maria; Gao, Jianjun; Farzana, Jasmine; Roy, Shantanu; Paul-Brutus, Rachelle; Rahaman, Ronald; Rakibuz-Zaman, Muhammad; Parvez, Faruque; Ahmed, Alauddin; Quasem, Iftekhar; Hore, Samar K; Alam, Shafiul; Islam, Tariqul; Harjes, Judith; Sarwar, Golam; Slavkovich, Vesna; Gamble, Mary V; Chen, Yu; Yunus, Mohammad; Rahman, Mahfuzar; Baron, John A; Graziano, Joseph H; Ahsan, Habibul

2013-12-01

Arsenic exposure through drinking water is a serious global health issue. Observational studies suggest that individuals who metabolize arsenic efficiently are at lower risk for toxicities such as arsenical skin lesions. Using two single nucleotide polymorphisms(SNPs) in the 10q24.32 region (near AS3MT) that show independent associations with metabolism efficiency, Mendelian randomization can be used to assess whether the association between metabolism efficiency and skin lesions is likely to be causal. Using data on 2060 arsenic-exposed Bangladeshi individuals, we estimated associations for two 10q24.32 SNPs with relative concentrations of three urinary arsenic species (representing metabolism efficiency): inorganic arsenic (iAs), monomethylarsonic acid(MMA) and dimethylarsinic acid (DMA). SNP-based predictions of iAs%, MMA% and DMA% were tested for association with skin lesion status among 2483 cases and 2857 controls. Causal odds ratios for skin lesions were 0.90 (95% confidence interval[CI]: 0.87, 0.95), 1.19 (CI: 1.10, 1.28) and 1.23 (CI: 1.12, 1.36)for a one standard deviation increase in DMA%, MMA% and iAs%,respectively. We demonstrated genotype-arsenic interaction, with metabolism-related variants showing stronger associations with skin lesion risk among individuals with high arsenic exposure (synergy index: 1.37; CI: 1.11, 1.62). We provide strong evidence for a causal relationship between arsenic metabolism efficiency and skin lesion risk. Mendelian randomization can be used to assess the causal role of arsenic exposure and metabolism in a wide array of health conditions.exposure and metabolism in a wide array of health conditions.Developing interventions that increase arsenic metabolism efficiency are likely to reduce the impact of arsenic exposure on health.

Health Effects of Chronic Arsenic Exposure

Directory of Open Access Journals (Sweden)

Young-Seoub Hong

2014-09-01

Full Text Available Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.

Sequestration of arsenic in ombrotrophic peatlands

Science.gov (United States)

Rothwell, James; Hudson-Edwards, Karen; Taylor, Kevin; Polya, David; Evans, Martin; Allott, Tim

2014-05-01

Peatlands can be important stores of arsenic but we are lacking spectroscopic evidence of the sequestration pathways of this toxic metalloid in peatland environments. This study reports on the solid-phase speciation of anthropogenically-derived arsenic in atmospherically contaminated peat from the Peak District National Park (UK). Surface and sub-surface peat samples were analysed by synchrotron X-ray absorption spectroscopy on B18 beamline at Diamond Light Source (UK). The results suggest that there are contrasting arsenic sequestration mechanisms in the peat. The bulk arsenic speciation results, in combination with strong arsenic-iron correlations at the surface, suggest that iron (hydr)oxides are key phases for the immobilisation of arsenic at the peat surface. In contrast, the deeper peat samples are dominated by arsenic sulphides (arsenopyrite, realgar and orpiment). Given that these peats receive inputs solely from the atmosphere, the presence of these sulphide phases suggests an in-situ authigenic formation. Redox oscillations in the peat due to a fluctuating water table and an abundant store of legacy sulphur from historic acid rain inputs may favour the precipitation of arsenic sequestering sulphides in sub-surface horizons. Oxidation-induced loss of these arsenic sequestering sulphur species by water table drawdown has important implications for the mobility of arsenic and the quality of waters draining peatlands.

Arsenic speciation in hair and nails of acute promyelocytic leukemia (APL) patients undergoing arsenic trioxide treatment.

Science.gov (United States)

Chen, Baowei; Cao, Fenglin; Lu, Xiufen; Shen, Shengwen; Zhou, Jin; Le, X Chris

2018-07-01

Arsenic in hair and nails has been used to assess chronic exposure of humans to environmental arsenic. However, it remains to be seen whether it is appropriate to evaluate acute exposure to sub-lethal doses of arsenic typically used in therapeutics. In this study, hair, fingernail and toenail samples were collected from nine acute promyelocytic leukemia (APL) patients who were administered intravenously the daily dose of 10 mg arsenic trioxide (7.5 mg arsenic) for up to 54 days. These hair and nail samples were analyzed for arsenic species using high performance liquid chromatography separation and inductively coupled plasma mass spectrometry detection (HPLC-ICPMS). Inorganic arsenite was the predominant form among water-extractable arsenicals. Dimethylarsinic acid (DMA V ), monomethylarsonic acid (MMA V ), monomethylarsonous acid (MMA III ), monomethylmonothioarsonic acid (MMMTA V ), and dimethylmonothioarsinic acid (DMMTA V ) were also detected in both hair and nail samples. This is the first report of the detection of MMA III and MMMTA V as metabolites of arsenic in hair and nails of APL patients. Copyright © 2018 Elsevier B.V. All rights reserved.

Arsenic downregulates tight junction claudin proteins through p38 and NF-κB in intestinal epithelial cell line, HT-29

International Nuclear Information System (INIS)

Jeong, Chang Hee; Seok, Jin Sil; Petriello, Michael C.; Han, Sung Gu

2017-01-01

Arsenic is a naturally occurring metalloid that often is found in foods and drinking water. Human exposure to arsenic is associated with the development of gastrointestinal problems such as fluid loss, diarrhea and gastritis. Arsenic is also known to induce toxic responses including oxidative stress in cells of the gastrointestinal track. Tight junctions (TJs) regulate paracellular permeability and play a barrier role by inhibiting the movement of water, solutes and microorganisms in the paracellular space. Since oxidative stress and TJ damage are known to be associated, we examined whether arsenic produces TJ damage such as downregulation of claudins in the human colorectal cell line, HT-29. To confirm the importance of oxidative stress in arsenic-induced TJ damage, effects of the antioxidant compound (e.g., N-acetylcysteine (NAC)) were also determined in cells. HT-29 cells were treated with arsenic trioxide (40 μM, 12 h) to observe the modified expression of TJ proteins. Arsenic decreased expression of TJ proteins (i.e., claudin-1 and claudin-5) and transepithelial electrical resistance (TEER) whereas pretreatment of NAC (5–10 mM, 1 h) attenuated the observed claudins downregulation and TEER. Arsenic treatment produced cellular oxidative stress via superoxide generation and lowering glutathione (GSH) levels, while NAC restored cellular GSH levels and decreased oxidative stress. Arsenic increased phosphorylation of p38 and nuclear translocation of nuclear factor-kappa B (NF-κB) p65, while NAC attenuated these intracellular events. Results demonstrated that arsenic can damage intestinal epithelial cells by proinflammatory process (oxidative stress, p38 and NF-κB) which resulted in the downregulation of claudins and NAC can protect intestinal TJs from arsenic toxicity.

Neutron activation analysis of arsenic in Greece

International Nuclear Information System (INIS)

Grimanis, A.P.

1989-01-01

Arsenic is considered a toxic trace element for plant, animal, and human organisms. Arsenic and certain arsenic compounds have been listed as carcinogens by the U.S. Environmental Protection Agency. Arsenic is emitted in appreciable quantities into the atmosphere by coal combustion and the production of cement. Arsenic enters the aquatic environment through industrial activities such as smelting of metallic ores, metallurgical glassware, and ceramics as well as insecticide production and use. Neutron activation analysis (NAA) is a very sensitive, precise, and accurate method for determining arsenic. This paper is a review of research studies of arsenic in the Greek environment by NAA performed at our radioanalytical laboratory. The objectives of these studies were (a) to determine levels of arsenic concentrations in environmental materials, (b) to pinpoint arsenic pollution sources and estimate the extent of arsenic pollution, and (c) to find out whether edible marine organisms from the gulfs of Greece receiving domestic, industrial, and agricultural wastes have elevated concentrations of arsenic in their tissues that could render them dangerous for human consumption

Arsenic and Antimony Transporters in Eukaryotes

Directory of Open Access Journals (Sweden)

Ewa Maciaszczyk-Dziubinska

2012-03-01

Full Text Available Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters.

Arsenic and Antimony Transporters in Eukaryotes

Science.gov (United States)

Maciaszczyk-Dziubinska, Ewa; Wawrzycka, Donata; Wysocki, Robert

2012-01-01

Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters. PMID:22489166

Determination of total inorganic arsenic in potable water through spectroscopy of atomic absorption with generation of hydride

International Nuclear Information System (INIS)

Rodriguez Roman, S.

1997-01-01

This study developed a method for the cuantitative analysis of arsenic in potable water , through the spectrophotometric technique of atomic absorption. It used an automatic system of injection of flux for the generation of hydrides. It studied the effect produced by reducer agents, in the prereduction of arsenic in water, obtaining the best result with the use of potasium iodide 1.5% and ascorbic acid 0.25% in hydrochloric acid 3.7%, for the direct determination of total inorganic arsenic. It observed the effect produced by cadmium and selenium to the half of the concentration of arsenic, chromium, lead and silver at the same concentration, and barium at a ten times higher concentration, in the recuperation of total inorganic arsenic. It also used sodium borohydride 0.3% in sodium hydroxide 0.05% (5mL/min), for the formation of the volatile hydrides. It used hydrochloric acid 3.7% (12 mL/min) as disolution of transport; argon as inert gas, and a flame air-acetylene, for the atomization of the hydrides. This method was applied to 19 samples of potable water, and the result was no detectable for all of them. (S. Grainger)

Uptake and transformation of arsenic during the vegetative life stage of terrestrial fungi

International Nuclear Information System (INIS)

Nearing, Michelle M.; Koch, Iris; Reimer, Kenneth J.

2015-01-01

Many species of terrestrial fungi produce fruiting bodies that contain high proportions of arsenobetaine (AB), an arsenic compound of no known toxicity. It is unknown whether fungi produce or accumulate AB from the surrounding environment. The present study targets the vegetative life stage (mycelium) of fungi, to examine the role of this stage in arsenic transformations and potential formation of AB. The mycelia of three different fungi species were cultured axenically and exposed to AB, arsenate (As(V)) and dimethylarsinoyl acetic acid for 60 days. Agaricus bisporus was additionally exposed to hypothesized precursors for AB and the exposure time to As(V) and dimethlyarsinic acid was also extended to 120 days. The mycelia of all fungi species accumulated all arsenic compounds with two species accumulating significantly more AB than other compounds. Few biotransformations were observed in these experiments indicating that it is unlikely that the mycelium of the fungus is responsible for biosynthesizing AB. - Highlights: • Mycelia of terrestrial fungi were exposed to arsenobetaine (AB) and potential precursors. • Mycelium may be selectively accumulating AB and transporting it to fruiting bodies. • Mycelium did not biosynthesize AB. - Mycelia of edible mushrooms preferentially accumulate arsenobetaine but do not biosynthesize this non-toxic arsenical

MDI Biological Laboratory Arsenic Summit: Approaches to Limiting Human Exposure to Arsenic

OpenAIRE

Stanton, Bruce A.

2015-01-01

This report is the outcome of the meeting: “Environmental and Human Health Consequences of Arsenic”, held at the MDI Biological Laboratory in Salisbury Cove, Maine, August 13–15, 2014. Human exposure to arsenic represents a significant health problem worldwide that requires immediate attention according to the World Health Organization (WHO). One billion people are exposed to arsenic in food and more than 200 million people ingest arsenic via drinking water at concentrations greater than inte...

A novel approach for arsenic adsorbents regeneration using MgO.

Science.gov (United States)

Tresintsi, Sofia; Simeonidis, Konstantinos; Katsikini, Maria; Paloura, Eleni C; Bantsis, Georgios; Mitrakas, Manassis

2014-01-30

An integrated procedure for the regeneration of iron oxy-hydroxide arsenic adsorbents by granulated MgO is proposed in this study. A continuous recirculation configuration, with a NaOH solution flowing sequentially through the saturated adsorbent (leaching step) and the MgO (adsorption step) column beds, was optimized by utilizing the high arsenic adsorption efficiency of MgO at strong alkaline environments. Experimental results indicated that the total amount of leached arsenic was captured by MgO whereas the regenerated iron oxy-hydroxide recovered around 80% of its removal capacity upon reuse. The improved adsorption capacity of MgO for As(V), which is maximized at pH 10, is explained by the intermediate hydration to Mg(OH)2 and the following As(V) oxy-anions adsorption on its surface through the formation of monodentate inner sphere complexes, as it is deduced from the AsK-edge X-ray absorption fine structure (EXAFS) analysis. In addition to the economical-benefits, corresponding tests proved that the solid wastes of this process, namely spent MgO/Mg(OH)2, can be environmentally safely disposed as stable additives in cement products, while the alkaline solution is completely detoxified and can be recycled to the regeneration task. Copyright © 2013 Elsevier B.V. All rights reserved.

Relationship between arsenic and selenium in workers occupationally exposed to inorganic arsenic.

Science.gov (United States)

Janasik, Beata; Zawisza, Anna; Malachowska, Beata; Fendler, Wojciech; Stanislawska, Magdalena; Kuras, Renata; Wasowicz, Wojciech

2017-07-01

The interaction between arsenic (As) and selenium (Se) has been one of the most extensively studied. The antagonism between As and Se suggests that low Se status plays an important role in aggravating arsenic toxicity in diseases development. The objective of this study was to assess the Se contents in biological samples of inorganic As exposed workers (n=61) and in non-exposed subjects (n=52). Median (Me) total arsenic concentration in urine of exposed workers was 21.83μg/g creat. (interquartile range (IQR) 15.49-39.77) and was significantly higher than in the control group - (Me 3.75μg/g creat. (IQR 2.52-9.26), piAs+MMA+DMA) was significantly associated with the high total selenium urine excretion (B=0.14 (95%CI (confidence interval) 0.05-0.23)). Combination of both arsenic and selenium status to assess the risk of arsenic-induced diseases requires more studies with regard to both the analysis of speciation, genetics and the influence of factors such as nutritional status. Copyright © 2017 Elsevier GmbH. All rights reserved.

Arsenic K-edge X-ray absorption near-edge spectroscopy to determine oxidation states of arsenic of a coastal aquifer–aquitard system

International Nuclear Information System (INIS)

Wang, Ya; Jiao, Jiu Jimmy; Zhu, Sanyuan; Li, Yiliang

2013-01-01

Determination of oxidation states of solid-phase arsenic in bulk sediments is a valuable step in the evaluation of its bioavailability and environmental fate in deposits, but is difficult when the sediments have low arsenic contents and heterogeneous distribution of arsenic species. As K-edge X-ray absorption near-edge spectroscopy (XANES) was used to determine quantitatively the oxidation states of arsenic in sediments collected from different depths of boreholes in the Pearl River Delta, China, where the highest aquatic arsenic concentration is 161.4 μg/L, but the highest solid arsenic content only 39.6 mg/kg. The results demonstrated that XANES is efficient in determining arsenic oxidation states of the sediments with low arsenic contents and multiple arsenic species. The study on the high-resolution vertical variations of arsenic oxidation states also indicated that these states are influenced strongly by groundwater activities. With the help of geochemical data, solid arsenic speciation, toxicity and availability were further discussed. -- Highlights: •XANES is efficient in determining arsenic oxidation states of the bulk sediments. •Distribution of arsenic oxidation states is consistent with geochemical conditions. •Arsenic oxidation states are influenced strongly by groundwater activities. -- As K-edge X-ray absorption near-edge spectroscopy is efficient in determining arsenic oxidation states of the bulk sediments with low arsenic contents and heterogeneous distribution of arsenic species

Russian ElectroKhimPribor integrated plant - producer and supplier of enriched stable isotopes

International Nuclear Information System (INIS)

Tatarinov, A.N.; Polyakov, L.A.

1997-01-01

Russian ElectroKhimPribor Integrated Plant, as well as ORNL, is a leading production which manufactures and supplied to the world market such specific products as stable isotopes. More than 200 isotopes of 44 elements can be obtained at its electromagnetic separator. Changes being underway for a few last years in Russia affected production and distribution of stable isotopes. There arose a necessity in a new approach to handling work in this field so as to create favourable conditions for both producers and customers. As a result, positive changes in calutron operation at ElectroKhimPribor has been reached; quality management system covering all stages of production has been set up; large and attractive stock of isotopes has been created; prospective scientific isotope-based developments are taken into account when planning separation F campaigns; executing the contracts is guaranteed; business philosophy has been changed to meet maximum of customer needs. For more than forty years ElectroKhimPribor have had no claim from customers as to quality of products or implementing contracts. Supplying enriched stable isotopes virtually to all the world's leading customers, ElectroKhimPribor cooperates successfully with Canadian company Trace Science since 1996

Voltammetric Study of Arsenic (III and Arsenic (V in Ground Water of Hajigonj and Kalkini in Bangladesh

Directory of Open Access Journals (Sweden)

Mohammad Arifur Rahman

2008-06-01

Full Text Available The speciation of arsenic in groundwater samples using Square Wave Anodic Stripping Voltammetry (SWASV, Differential Pulse Anodic Stripping Voltammetry (DPASV and Normal Pulse Anodic Stripping Voltammetry (NPASV are described. Good resolution of the species, arsenic (III and arsenic (V is achieved using SWASV. The reliability of the methods was checked by analyzing the total arsenic content of the samples by Hydride Generation Atomic Absorptioion Spectrophotometer and by analyzing prepared controlled laboratory standard solution. Since this technique is comparatively cheaper than other available techniques it could be a better analytical technique for arsenic speciation from water. In this study, the assessment of inorganic arsenic species in ground water of Kalkini (Madaripur and Hajigonj (Chandpur is reported. It shows that arsenic content in water in different locations is irregular. Most of the locations contain higher level of As(III than As(V. The highest concentration of arsenic is found in Anayetnagor (554.46 ± 0.07 mg/L of Kalkini and Raichar (562 ± 0.50 mg/L of Hajigonj. However, the level of total arsenic and As(III of most of the villages of the study areas are more than the WHO guideline value (50mg/L. Therefore a proper monitoring process should be evolved along with the development of methods to keep the water free from arsenic.

Removal of arsenic from contaminated groundwater by solar-driven membrane distillation

International Nuclear Information System (INIS)

Manna, Ajay K.; Sen, Mou; Martin, Andrew R.; Pal, Parimal

2010-01-01

Experimental investigations were carried out on removal of arsenic from contaminated groundwater by employing a new flat-sheet cross flow membrane module fitted with a hydrophobic polyvinylidenefluoride (PVDF) microfiltration membrane. The new design of the solar-driven membrane module in direct contact membrane distillation (DCMD) configuration successfully produced almost 100 per cent arsenic-free water from contaminated groundwater in a largely fouling-free operation while permitting high fluxes under reduced temperature polarization. For a feed flow rate of 0.120 m 3 /h, the 0.13 μm PVDF membrane yielded a high flux of 74 kg/(m 2 h) at a feed water temperature of 40 deg. C and, 95 kg/m 2 h at a feed water temperature of 60 deg. C. The encouraging results show that the design could be effectively exploited in the vast arsenic-affected rural areas of South-East Asian countries blessed with abundant sunlight particularly during the critical dry season. - Solar-driven membrane distillation has the potential of removing arsenic from contaminated groundwater.

Arsenic removal by lime softening

DEFF Research Database (Denmark)

Kaosol, T.; Suksaroj, C.; Bregnhøj, Henrik

2002-01-01

This paper focuses on the study of arsenic removal for drinking water by lime softening. The initial arsenic (V) concentration was 500 and 1,000 ug/L in synthetic groundwater. The experiments were performed as batch tests with varying lime dosages and mixing time. For the synthetic groundwater......, arsenic (V) removal increased with increasing lime dosage and mixing time, as well as with the resulting pH. The residual arsenic (V) in all cases was lower than the WHO guideline of 10 ug/L at pH higher than 11.5. Kinetic of arsenic (V) removal can be described by a first-order equation as C1 = C0*e......^-k*t. The relation between the constant (k value) and increasing lime dosage was found to be linear, described by k = 0.0034 (Dlime). The results support a theory from the literature that the arsenic (V) was removed by precipitation af Ca3(AsO4)2. The results obtained in the present study suggest that lime...

Incorporation of arsenic into gypsum: Relevant to arsenic removal and immobilization process in hydrometallurgical industry

Energy Technology Data Exchange (ETDEWEB)

Zhang, Danni; Yuan, Zidan [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Shaofeng, E-mail: wangshaofeng@iae.ac.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Jia, Yongfeng, E-mail: yongfeng.jia@iae.ac.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Demopoulos, George P. [Department of Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada)

2015-12-30

Highlights: • Quantitatively studied the incorporation of arsenic into the structure of gypsum. • Arsenic content in the solid increased with pH and initial arsenic concentration. • Calcium arsenate phase precipitated in addition to gypsum at higher pH values. • The structure of gypsum and its morphology was altered by the incorporated arsenate. • The incorporated arsenate formed sainfeldite-like local structure in gypsum. - Abstract: Gypsum precipitates as a major secondary mineral during the iron-arsenate coprecipitation process for the removal of arsenic from hydrometallurgical effluents. However, its role in the fixation of arsenic is still unknown. This work investigated the incorporation of arsenic into gypsum quantitatively during the crystallization process at various pHs and the initial arsenic concentrations. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray absorption near edge spectroscopy (XANES) and scanning electron microscopy (SEM) were employed to characterize the coprecipitated solids. The results showed that arsenate was measurably removed from solution during gypsum crystallization and the removal increased with increasing pH. At lower pH where the system was undersaturated with respect to calcium arsenate, arsenate ions were incorporated into gypsum structure, whereas at higher pH, calcium arsenate was formed and constituted the major arsenate bearing species in the precipitated solids. The findings may have important implications for arsenic speciation and stability of the hydrometallurgical solid wastes.

Arsenic chemistry in soils and sediments

Energy Technology Data Exchange (ETDEWEB)

Fendorf, S.; Nico, P.; Kocar, B.D.; Masue, Y.; Tufano, K.J.

2009-10-15

Arsenic is a naturally occurring trace element that poses a threat to human and ecosystem health, particularly when incorporated into food or water supplies. The greatest risk imposed by arsenic to human health results from contamination of drinking water, for which the World Health Organization recommends a maximum limit of 10 {micro}g L{sup -1}. Continued ingestion of drinking water having hazardous levels of arsenic can lead to arsenicosis and cancers of the bladder, skin, lungs and kidneys. Unfortunately, arsenic tainted drinking waters are a global threat and presently having a devastating impact on human health within Asia. Nearly 100 million people, for example, are presently consuming drinking water having arsenic concentrations exceeding the World Health Organization's recommended limit (Ahmed et al., 2006). Arsenic contamination of the environment often results from human activities such as mining or pesticide application, but recently natural sources of arsenic have demonstrated a devastating impact on water quality. Arsenic becomes problematic from a health perspective principally when it partitions into the aqueous rather than the solid phase. Dissolved concentrations, and the resulting mobility, of arsenic within soils and sediments are the combined result of biogeochemical processes linked to hydrologic factors. Processes favoring the partitioning of As into the aqueous phase, potentially leading to hazardous concentrations, vary extensively but can broadly be grouped into four categories: (1) ion displacement, (2) desorption (or limited sorption) at pH values > 8.5, (3) reduction of arsenate to arsenite, and (4) mineral dissolution, particularly reductive dissolution of Fe and Mn (hydr)oxides. Although various processes may liberate arsenic from solids, a transition from aerobic to anaerobic conditions, and commensurate arsenic and iron/manganese reduction, appears to be a dominant, but not exclusive, means by which high concentrations of

Adsorption and reaction mechanism of arsenic vapors over γ-Al2O3 in the simulated flue gas containing acid gases.

Science.gov (United States)

Hu, Hongyun; Chen, Dunkui; Liu, Huan; Yang, Yuhan; Cai, Hexun; Shen, Junhao; Yao, Hong

2017-08-01

Arsenic emission from fuel combustion and metal smelting flue gas causes serious pollution. Addition of sorbents is a promising way for the arsenic capture from high temperature flue gas. However, it is difficult to remove arsenic from SO 2 /HCl-rich flue gas due to the competitive reaction of the sorbents with arsenic and these acid gases. To solve this problem, arsenic adsorption over γ-Al 2 O 3 was studied in this work to evaluate its adsorption mechanism, resistance to acid gases as well as regeneration behavior. The results show that γ-Al 2 O 3 had good resistance to acid gases and the arsenic adsorption by γ-Al 2 O 3 could be effectively carried out at a wide temperature range between 573 and 1023 K. Nevertheless, adsorption at higher-temperature (like 1173 K) leaded to the decrease of surface area and the rearrangement of crystal structure of γ-Al 2 O 3 , reducing the active sites for arsenic adsorption. The adsorption of arsenic was confirmed to occur at different active sites in γ-Al 2 O 3 by forming various adsorbed species. Increasing temperature facilitated arsenic transformation into more stable chemisorbed As 3+ and As 5+ which were difficult to remove through thermal treatment regeneration. Fortunately, the regeneration of spent γ-Al 2 O 3 could be well performed using NaOH solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Investigation of the association between arsenic levels in drinking water and suicide rate of Hungarian settlements between 2005 and 2011. A preliminary study].

Science.gov (United States)

Rihmer, Zoltán; Hal, Melinda; Kapitány, Balázs; Gonda, Xénia; Vargha, Márta; Döme, Péter

2016-01-01

Both suicidal behaviour and consumption of arsenic-contaminated drinking-water represent major public health problems. Previous epidemiological and animal studies showed that high arsenic intake may also be associated with the elevated risk for depression. Since untreated depression is the most powerful risk factor for suicidal behaviour, we postulated that the consumption of arsenic-contaminated tap drinking-water may also be related to suicide. Based on the level of arsenic in their drinking water Hungarian settlements with more then 500 inhabitants (n=1639) were divided into four groups. Then average age-standardized suicide rates of the four groups were compared. We found that the higher is the arsenic level in the drinking water the higher is the suicide rate of the settlements. In addition to the practical consequences of our preliminary results (e.g. in the suicide prevention) they also suggest that high level of arsenic in drinking water might contribute, at least in part, to the well-known and stable in time regional differences in suicide mortality of Hungary since the highest arsenic levels in drinking water have been found in counties with traditionally high suicide rates, such as Bacs-Kiskun, Csongrad, Bekes and Hajdu- Bihar.

Understanding Arsenic Dynamics in Agronomic Systems to ...

Science.gov (United States)

This review is on arsenic in agronomic systems, and covers processes that influence the entry of arsenic into the human food supply. The scope is from sources of arsenic (natural and anthropogenic) in soils, biogeochemical and rhizosphere processes that control arsenic speciation and availability, through to mechanisms of uptake by crop plants and potential mitigation strategies. This review makes a case for taking steps to prevent or limit crop uptake of arsenic, wherever possible, and to work toward a long-term solution to the presence of arsenic in agronomic systems. The past two decades have seen important advances in our understanding of how biogeochemical and physiological processes influence human exposure to soil arsenic, and thus must now prompt an informed reconsideration and unification of regulations to protect the quality of agricultural and residential soils. Consumption of staple foods such as rice, beverages such as apple juice, or vegetables grown in historically arsenic-contaminated soils is now recognized as a tangible route of arsenic exposure that, in many cases, is more significant than exposure from drinking water. Understanding the sources of arsenic to crop plants and the factors that influence them is key to reducing exposure now and preventing exposure in future. In addition to the abundant natural sources of arsenic, there are a large number of industrial and agricultural sources of arsenic to the soil; from mining wastes, coal fly

Arsenic: natural and anthropogenic

National Research Council Canada - National Science Library

Matschullat, Jörg; Deschamps, Eleonora

2011-01-01

.... Based on state-of-the-art investigations into the global arsenic cycle, the related human toxicology and available remediation technologies, it assesses arsenic in all the environmental compartments...

Arsenic transport by zebrafish aquaglyceroporins

Directory of Open Access Journals (Sweden)

Landfear Scott M

2009-11-01

Full Text Available Abstract Background Arsenic is one of the most ubiquitous toxins and endangers the health of tens of millions of humans worldwide. It is a mainly a water-borne contaminant. Inorganic trivalent arsenic (AsIII is one of the major species that exists environmentally. The transport of AsIII has been studied in microbes, plants and mammals. Members of the aquaglyceroporin family have been shown to actively conduct AsIII and its organic metabolite, monomethylarsenite (MAsIII. However, the transport of AsIII and MAsIII in in any fish species has not been characterized. Results In this study, five members of the aquaglyceroporin family from zebrafish (Danio rerio were cloned, and their ability to transport water, glycerol, and trivalent arsenicals (AsIII and MAsIII and antimonite (SbIII was investigated. Genes for at least seven aquaglyceroporins have been annotated in the zebrafish genome project. Here, five genes which are close homologues to human AQP3, AQP9 and AQP10 were cloned from a zebrafish cDNA preparation. These genes were named aqp3, aqp3l, aqp9a, aqp9b and aqp10 according to their similarities to the corresponding human AQPs. Expression of aqp9a, aqp9b, aqp3, aqp3l and aqp10 in multiple zebrafish organs were examined by RT-PCR. Our results demonstrated that these aquaglyceroporins exhibited different tissue expression. They are all detected in more than one tissue. The ability of these five aquaglyceroporins to transport water, glycerol and the metalloids arsenic and antimony was examined following expression in oocytes from Xenopus leavis. Each of these channels showed substantial glycerol transport at equivalent rates. These aquaglyceroporins also facilitate uptake of inorganic AsIII, MAsIII and SbIII. Arsenic accumulation in fish larvae and in different tissues from adult zebrafish was studied following short-term arsenic exposure. The results showed that liver is the major organ of arsenic accumulation; other tissues such as gill, eye

Determination of arsenic compounds in earthworms

Energy Technology Data Exchange (ETDEWEB)

Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology

1998-08-01

Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

Variability in human metabolism of arsenic

International Nuclear Information System (INIS)

Loffredo, C.A.; Aposhian, H.V.; Cebrian, M.E.; Yamauchi, Hiroshi; Silbergeld, E.K.

2003-01-01

Estimating the nature and extent of human cancer risks due to arsenic (As) in drinking water is currently of great concern, since millions of persons worldwide are exposed to arsenic, primarily through natural enrichment of drinking water drawn from deep wells. Humans metabolize and eliminate As through oxidative methylation and subsequent urinary excretion. While there is debate as to the role of methylation in activation/detoxification, variations in arsenic metabolism may affect individual risks of toxicity and carcinogenesis. Using data from three populations, from Mexico, China, and Chile, we have analyzed the distribution in urine of total arsenic and arsenic species (inorganic arsenic (InAs), monomethyl arsenic (MMA), and dimethyl arsenic (DMA). Data were analyzed in terms of the concentration of each species and by evaluating MMA:DMA and (MMA+DMA):InAs ratios. In all persons most urinary As was present as DMA. Male:female differences were discernible in both high- and low-exposure groups from all three populations, but the gender differences varied by populations. The data also indicated bimodal distributions in the ratios of DMA to InAs and to MMA. While the gene or genes responsible for arsenic methylation are still unknown, the results of our studies among the ethnic groups in this study are consistent with the presence of functional genetic polymorphisms in arsenic methylation leading to measurable differences in toxicity. This analysis highlights the need for continuing research on the health effects of As in humans using molecular epidemiologic methods

Mathematical model insights into arsenic detoxification

Directory of Open Access Journals (Sweden)

Nijhout H Frederik

2011-08-01

Full Text Available Abstract Background Arsenic in drinking water, a major health hazard to millions of people in South and East Asia and in other parts of the world, is ingested primarily as trivalent inorganic arsenic (iAs, which then undergoes hepatic methylation to methylarsonic acid (MMAs and a second methylation to dimethylarsinic acid (DMAs. Although MMAs and DMAs are also known to be toxic, DMAs is more easily excreted in the urine and therefore methylation has generally been considered a detoxification pathway. A collaborative modeling project between epidemiologists, biologists, and mathematicians has the purpose of explaining existing data on methylation in human studies in Bangladesh and also testing, by mathematical modeling, effects of nutritional supplements that could increase As methylation. Methods We develop a whole body mathematical model of arsenic metabolism including arsenic absorption, storage, methylation, and excretion. The parameters for arsenic methylation in the liver were taken from the biochemical literature. The transport parameters between compartments are largely unknown, so we adjust them so that the model accurately predicts the urine excretion rates of time for the iAs, MMAs, and DMAs in single dose experiments on human subjects. Results We test the model by showing that, with no changes in parameters, it predicts accurately the time courses of urinary excretion in mutiple dose experiments conducted on human subjects. Our main purpose is to use the model to study and interpret the data on the effects of folate supplementation on arsenic methylation and excretion in clinical trials in Bangladesh. Folate supplementation of folate-deficient individuals resulted in a 14% decrease in arsenicals in the blood. This is confirmed by the model and the model predicts that arsenicals in the liver will decrease by 19% and arsenicals in other body stores by 26% in these same individuals. In addition, the model predicts that arsenic

Arsenic in the soils of Zimapan, Mexico

Energy Technology Data Exchange (ETDEWEB)

Ongley, Lois K. [Oak Hill High School, P.O. Box 400, Sabattus, ME 04280 (United States)]. E-mail: loisongley@earthlink.net; Sherman, Leslie [Department of Chemistry, Washington College, 300 Washington Avenue, Chestertown, MD 21620 (United States); Armienta, Aurora [Instituto de Geofisica, UNAM, Mexico D.F. 04510 (Mexico); Concilio, Amy [Department of Earth, Ecological, and Environmental Sciences, University of Toledo, Toledo, OH 43606 (United States); Salinas, Carrie Ferguson [Department of Agronomy and Environmental Management, Louisiana State University, Baton Rouge, LA 70803 (United States)

2007-02-15

Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg{sup -1}. Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg{sup -1} only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic.

Arsenic in the soils of Zimapan, Mexico

International Nuclear Information System (INIS)

Ongley, Lois K.; Sherman, Leslie; Armienta, Aurora; Concilio, Amy; Salinas, Carrie Ferguson

2007-01-01

Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg -1 . Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg -1 only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic

Arsenic speciation and sorption in natural environments

Science.gov (United States)

Campbell, Kate M.; Nordstrom, D. Kirk

2014-01-01

Aqueous arsenic speciation, or the chemical forms in which arsenic exists in water, is a challenging, interesting, and complicated aspect of environmental arsenic geochemistry. Arsenic has the ability to form a wide range of chemical bonds with carbon, oxygen, hydrogen, and sulfur, resulting in a large variety of compounds that exhibit a host of chemical and biochemical properties. Besides the intriguing chemical diversity, arsenic also has the rare capacity to capture our imaginations in a way that few elements can duplicate: it invokes images of foul play that range from sinister to comedic (e.g., “inheritance powder” and arsenic-spiked elderberry wine). However, the emergence of serious large-scale human health problems from chronic arsenic exposure in drinking water has placed a high priority on understanding environmental arsenic mobility, toxicity, and bioavailability, and chemical speciation is key to these important questions. Ultimately, the purpose of arsenic speciation research is to predict future occurrences, mitigate contamination, and provide successful management of water resources.

Protective effects of plasma alpha-tocopherols on the risk of inorganic arsenic-related urothelial carcinoma

International Nuclear Information System (INIS)

Chung, Chi-Jung; Pu, Yeong-Shiau; Chen, Ying-Ting; Su, Chien-Tien; Wu, Chia-Chang; Shiue, Horng-Sheng; Huang, Chao-Yuan; Hsueh, Yu-Mei

2011-01-01

Arsenic plays an important role in producing oxidative stress in cultured cells. To investigate the interaction between high oxidative stress and low arsenic methylation capacity on arsenic carcinogenesis, a case-control study was conducted to evaluate the relationship among the indices of oxidative stress, such as urinary 8-hydroxydeoxyquanine (8-OHdG), as well as plasma micronutrients and urinary arsenic profiles on urothelial carcinoma (UC) risk. Urinary 8-OHdG was measured using high-sensitivity enzyme-linked immunosorbent assay kits. The urinary arsenic species were analyzed using high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Plasma micronutrient levels were analyzed using reversed-phase high-performance liquid chromatography. The present study showed a significant protective effect of plasma alpha-tocopherol on UC risk. Plasma alpha-tocopherol levels were significantly inversely related to urinary total arsenic concentrations and inorganic arsenic percentage (InAs%), and significantly positively related to dimethylarsinic acid percentage (DMA%). There were no correlations between plasma micronutrients and urinary 8-OHdG. Study participants with lower alpha-tocopherol and higher urinary total arsenic, higher InAs%, higher MMA%, and lower DMA% had a higher UC risk than those with higher alpha-tocopherol and lower urinary total arsenic, lower InAs%, lower MMA%, and higher DMA%. These results suggest that plasma alpha-tocopherol might modify the risk of inorganic arsenic-related UC. - Research Highlights: → Plasma alpha-tocopherol levels were significantly inversely related to UC risk. → There were no correlations between plasma micronutrients and urinary 8-OHdG. → People with lower alpha-tocopherol and higher total arsenic had increased UC risk.

Protective effects of plasma alpha-tocopherols on the risk of inorganic arsenic-related urothelial carcinoma

Energy Technology Data Exchange (ETDEWEB)

Chung, Chi-Jung [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Chen, Ying-Ting [Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Wu, Chia-Chang [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, Taipei Medical Universtiy-Shuang Ho Hospital, Taipei, Taiwan (China); Shiue, Horng-Sheng [Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Huang, Chao-Yuan [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China)

2011-02-15

Arsenic plays an important role in producing oxidative stress in cultured cells. To investigate the interaction between high oxidative stress and low arsenic methylation capacity on arsenic carcinogenesis, a case-control study was conducted to evaluate the relationship among the indices of oxidative stress, such as urinary 8-hydroxydeoxyquanine (8-OHdG), as well as plasma micronutrients and urinary arsenic profiles on urothelial carcinoma (UC) risk. Urinary 8-OHdG was measured using high-sensitivity enzyme-linked immunosorbent assay kits. The urinary arsenic species were analyzed using high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Plasma micronutrient levels were analyzed using reversed-phase high-performance liquid chromatography. The present study showed a significant protective effect of plasma alpha-tocopherol on UC risk. Plasma alpha-tocopherol levels were significantly inversely related to urinary total arsenic concentrations and inorganic arsenic percentage (InAs%), and significantly positively related to dimethylarsinic acid percentage (DMA%). There were no correlations between plasma micronutrients and urinary 8-OHdG. Study participants with lower alpha-tocopherol and higher urinary total arsenic, higher InAs%, higher MMA%, and lower DMA% had a higher UC risk than those with higher alpha-tocopherol and lower urinary total arsenic, lower InAs%, lower MMA%, and higher DMA%. These results suggest that plasma alpha-tocopherol might modify the risk of inorganic arsenic-related UC. - Research Highlights: {yields} Plasma alpha-tocopherol levels were significantly inversely related to UC risk. {yields} There were no correlations between plasma micronutrients and urinary 8-OHdG. {yields} People with lower alpha-tocopherol and higher total arsenic had increased UC risk.

Urinary arsenic speciation and its correlation with 8-OHdG in Chinese residents exposed to arsenic through coal burning

Energy Technology Data Exchange (ETDEWEB)

Li, X.; Pi, J.B.; Li, B.; Xu, Y.Y.; Jin, Y.P.; Sun, G.F. [China Medical University, Shenyang (China). Dept. for Occupational & Environmental Health

2008-10-15

In contrast to arsenicosis caused by consumption of water contaminated by naturally occurring inorganic arsenic, human exposure to this metalloid through coal burning has been rarely reported. In this study, arsenic speciation and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in urine were determined in the Chinese residents exposed to arsenic through coal burning in Guizhou, China, an epidemic area of chronic arsenic poisoning caused by coal burning. The urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and total arsenic (tAs) of high-arsenic exposed subjects were significantly higher than those of low-arsenic exposed residents. A biomarker of oxidative DNA damage, urinary 8-OHdG level was significantly higher in high-arsenic exposed subjects than that of low exposed. Significant positive correlations were found between 8-OHdG levels and concentrations of iAs, MMA, DMA and tAs, respectively. In addition, a significant negative correlation was observed between 8-OHdG levels and the secondary methylation ratio (DMA/(MMA + DMA)). The results suggest that chronic arsenic exposure through burning coal rich in arsenic is associated with oxidative DNA damages, and that secondary methylation capacity is potentially related to the susceptibility of individuals to oxidative DNA damage induced by arsenic exposure through coal burning in domestic living.

Method of arsenic removal from water

Science.gov (United States)

Gadgil, Ashok

2010-10-26

A method for low-cost arsenic removal from drinking water using chemically prepared bottom ash pre-treated with ferrous sulfate and then sodium hydroxide. Deposits on the surface of particles of bottom ash form of activated iron adsorbent with a high affinity for arsenic. In laboratory tests, a miniscule 5 grams of pre-treated bottom ash was sufficient to remove the arsenic from 2 liters of 2400 ppb (parts per billion) arsenic-laden water to a level below 50 ppb (the present United States Environmental Protection Agency limit). By increasing the amount of pre-treated bottom ash, even lower levels of post-treatment arsenic are expected. It is further expected that this invention supplies a very low-cost solution to arsenic poisoning for large population segments.

Determinants and Consequences of Arsenic Metabolism Efficiency among 4,794 Individuals: Demographics, Lifestyle, Genetics, and Toxicity.

Science.gov (United States)

Jansen, Rick J; Argos, Maria; Tong, Lin; Li, Jiabei; Rakibuz-Zaman, Muhammad; Islam, Md Tariqul; Slavkovich, Vesna; Ahmed, Alauddin; Navas-Acien, Ana; Parvez, Faruque; Chen, Yu; Gamble, Mary V; Graziano, Joseph H; Pierce, Brandon L; Ahsan, Habibul

2016-02-01

Exposure to inorganic arsenic (iAs), a class I carcinogen, affects several hundred million people worldwide. Once absorbed, iAs is converted to monomethylated (MMA) and then dimethylated forms (DMA), with methylation facilitating urinary excretion. The abundance of each species in urine relative to their sum (iAs%, MMA%, and DMA%) varies across individuals, reflecting differences in arsenic metabolism capacity. The association of arsenic metabolism phenotypes with participant characteristics and arsenical skin lesions was characterized among 4,794 participants in the Health Effects of Arsenic Longitudinal Study (Araihazar, Bangladesh). Metabolism phenotypes include those obtained from principal component (PC) analysis of arsenic species. Two independent PCs were identified: PC1 appears to represent capacity to produce DMA (second methylation step), and PC2 appears to represent capacity to convert iAs to MMA (first methylation step). PC1 was positively associated (P 4.32/AS3MT region polymorphisms were strongly associated with PC1, but not PC2. Patterns of association for most variables were similar for PC1 and DMA%, and for PC2 and MMA% with the exception of arsenic exposure and SNP associations. Two distinct arsenic metabolism phenotypes show unique associations with age, sex, BMI, 10q24.32 polymorphisms, and skin lesions. This work enhances our understanding of arsenic metabolism kinetics and toxicity risk profiles. ©2015 American Association for Cancer Research.

Volatile arsenic species released from Escherichia coli expressing the AsIII S-adenosylmethionine methyltransferase gene.

Science.gov (United States)

Yuan, Chungang; Lu, Xiufen; Qin, Jie; Rosen, Barry P; Le, X Chris

2008-05-01

Biological systems, ranging from bacteria and fungi to humans, can methylate arsenic. Recent studies have suggested that the AsIII S-adenosylmethionine methyltransferase (arsM) gene in bacteria was responsible for the removal of arsenic as the volatile arsines from the bacteria. However, there has been no direct measure of the arsines released from bacteria cultures. We describe here an integrated system incorporating the bacterial incubation and volatile arsenic species analysis, and we demonstrate its application to the identification of the volatile arsines produced in bacterial cultures. The headspace of the bacterial cultures was purged with helium, and the volatile arsenic species were trapped in a chromatographic column immersed in liquid nitrogen. The cryogenically trapped arsines [AsH3, (CH3)AsH2, (CH3)2AsH, and (CH3)3As] were separated by gas chromatography and were detected by inductively coupled plasma mass spectrometry. A hydride generation system was coupled to the bacterial culture system, allowing for spiking standards and for generating calibration arsines necessary for quantitative analysis. Both bacteria containing the arsM gene or its variant arsMC2 gene were able to produce 400-500 ng of trimethylarsine. No trimethylarsine was detectable in bacteria lacking the arsM gene (containing the vector plasmid as negative control). These results confirm that arsM is responsible for releasing arsenic as volatile species from the arsenic-resistant bacteria. Our results also show traces of AsH3, CH3AsH2, and (CH3)2AsH in cultures of bacteria expressing arsM. The method detection limits for AsH3, CH3AsH2, (CH3)2AsH, and (CH3)3As were 0.5, 0.5, 0.7, and 0.6 pg, respectively. The ability to quantify trace levels of these volatile arsenic species makes it possible to study the biotransformation and biochemical roles of the evolution of these volatile arsenic species by biological systems.

Microbial Community Structure and Arsenic Biogeochemistry in Two Arsenic-Impacted Aquifers in Bangladesh

Directory of Open Access Journals (Sweden)

Edwin T. Gnanaprakasam

2017-11-01

Full Text Available Long-term exposure to trace levels of arsenic (As in shallow groundwater used for drinking and irrigation puts millions of people at risk of chronic disease. Although microbial processes are implicated in mobilizing arsenic from aquifer sediments into groundwater, the precise mechanism remains ambiguous. The goal of this work was to target, for the first time, a comprehensive suite of state-of-the-art molecular techniques in order to better constrain the relationship between indigenous microbial communities and the iron and arsenic mineral phases present in sediments at two well-characterized arsenic-impacted aquifers in Bangladesh. At both sites, arsenate [As(V] was the major species of As present in sediments at depths with low aqueous As concentrations, while most sediment As was arsenite [As(III] at depths with elevated aqueous As concentrations. This is consistent with a role for the microbial As(V reduction in mobilizing arsenic. 16S rRNA gene analysis indicates that the arsenic-rich sediments were colonized by diverse bacterial communities implicated in both dissimilatory Fe(III and As(V reduction, while the correlation analyses involved phylogenetic groups not normally associated with As mobilization. Findings suggest that direct As redox transformations are central to arsenic fate and transport and that there is a residual reactive pool of both As(V and Fe(III in deeper sediments that could be released by microbial respiration in response to hydrologic perturbation, such as increased groundwater pumping that introduces reactive organic carbon to depth.

Distributional patterns of arsenic concentrations in contaminant plumes offer clues to the source of arsenic in groundwater at landfills

Science.gov (United States)

Harte, Philip T.

2015-01-01

The distributional pattern of dissolved arsenic concentrations from landfill plumes can provide clues to the source of arsenic contamination. Under simple idealized conditions, arsenic concentrations along flow paths in aquifers proximal to a landfill will decrease under anthropogenic sources but potentially increase under in situ sources. This paper presents several conceptual distributional patterns of arsenic in groundwater based on the arsenic source under idealized conditions. An example of advanced subsurface mapping of dissolved arsenic with geophysical surveys, chemical monitoring, and redox fingerprinting is presented for a landfill site in New Hampshire with a complex flow pattern. Tools to assist in the mapping of arsenic in groundwater ultimately provide information on the source of contamination. Once an understanding of the arsenic contamination is achieved, appropriate remedial strategies can then be formulated.

Effect of alpha-lipoic acid on the removal of arsenic from arsenic-loaded isolated liver tissues of rat

Directory of Open Access Journals (Sweden)

Noor-E-Tabassum

2006-06-01

Full Text Available The patient of chronic arsenic toxicity shows oxidative stress. To overcome the oxidative stress, several antioxidants such as beta-carotene, ascorbic acid, α-tocopherol, zinc and selenium had been suggested in the treatment of chronic arsenic toxicity. In the present study universal antioxidant (both water and lipid soluble antioxidant α-lipoic acid was used to examine the effectiveness of reducing the amount of arsenic from arsenic-loaded isolated liver tissues of rat. Isolated liver tissues of Long Evans Norwegian rats were cut into small pieces and incubated first in presence or absence of arsenic and then with different concentrations of α-lipoic acid during the second incubation. α-Lipoic acid decreases the amount of arsenic and malondialdehyde (MDA in liver tissues as well as increases the reduced glutathione (GSH level in dose dependent manner. These results suggest that α-lipoic acid remove arsenic from arsenic-loaded isolated liver tissues of rat.

Poisoning of bees by industrial arsenic emissions

Energy Technology Data Exchange (ETDEWEB)

Jaroslav, S

1962-01-01

Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3 to 7 km. Settled fly-ash contained 0.0004 to 0.75 percent arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed.

Poisoning of bees by industrial arsenic emissions

Energy Technology Data Exchange (ETDEWEB)

Svoboda, J

1962-01-01

Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3-7 km. Settled fly-ash contained 0.0004-0.75% arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed. 5 references.

Airborne arsenic and urinary excretion of arsenic metabolites during boiler cleaning operations in a Slovak coal-fired power plant

Energy Technology Data Exchange (ETDEWEB)

Yager, J.W.; Hicks, J.B.; Fabianova, N. [EPRI, Palo Alto, CA (United States). Environment Group

1997-08-01

Little information is available on the relationship between occupational exposure to inorganic arsenic in coal fly ash and urinary excretion of arsenic metabolites. This study was undertaken in a coal-fired power plant in Slovakia during a routine maintenance outage. Arsenic was measured in the breathing zone of workers during 5 consecutive workdays, and urine samples were obtained for analysis of arsenic metabolites-inorganic arsenic (As), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) prior to the start of each shift. Results from a small number of cascade impacter air samples indicated that approximately 90% of total particle mass and arsenic was present in particle size fractions {ge} 3.5 {mu}m. The 8-hr time-weighted average (TWA) mean arsenic air concentration was 48.3 {mu}g/m{sup 3} (range 0.17-375.2) and the mean sum of urinary arsenic (Sigma As) metabolites was 16.9 {mu}g As/g creatinine (range 2.6-50.8). For an 8-hr TWA of 10 {mu}g/m{sup 3} arsenic from coal fly ash, the predicted mean concentration f the Sigma As urinary metabolites was 13.2 {mu}g As/g creatinine. Comparisons with previously published studies of exposure to arsenic trioxide vapors and dusts in copper smelters suggest that bioavailability of arsenic from airborne coal fly ash (as indicated by urinary excretion) is about one-third that seen in smelters and similar settings. Arsenic compound characteristics, matrix composition, and particle size distribution probably play major roles in determining actual uptake of airborne arsenic.

Evidence against the nuclear in situ binding of arsenicals-oxidative stress theory of arsenic carcinogenesis

International Nuclear Information System (INIS)

Kitchin, Kirk T.; Wallace, Kathleen

2008-01-01

A large amount of evidence suggests that arsenicals act via oxidative stress in causing cancer in humans and experimental animals. It is possible that arsenicals could bind in situ close to nuclear DNA followed by Haber-Weiss type oxidative DNA damage. Therefore, we tested this hypothesis by using radioactive 73 As labeled arsenite and vacuum filtration methodology to determine the binding affinity and capacity of 73 As arsenite to calf thymus DNA and Type 2A unfractionated histones, histone H3, H4 and horse spleen ferritin. Arsenicals are known to release redox active Fe from ferritin. At concentrations up to about 1 mM, neither DNA nor any of the three proteins studied, Type II-A histones, histone H3, H4 or ferritin, bound radioactive arsenite in a specific manner. Therefore, it appears highly unlikely that initial in situ binding of trivalent arsenicals, followed by in situ oxidative DNA damage, can account for arsenic's carcinogenicity. This experimental evidence (lack of arsenite binding to DNA, histone Type II-A and histone H3, H4) does not rule out other possible oxidative stress modes of action for arsenic such as (a) diffusion of longer lived oxidative stress molecules, such as H 2 O 2 into the nucleus and ensuing oxidative damage, (b) redox chemistry by unbound arsenicals in the nucleus, or (c) arsenical-induced perturbations in Fe, Cu or other metals which are already known to oxidize DNA in vitro and in vivo

Hydrological and Mineralogical Factors Influencing Paradoxical Groundwater Arsenic Release in the Red River Delta, Vietnam

Science.gov (United States)

Nghiem, A.; Bostick, B. C.

2017-12-01

In South and Southeast Asia, the widespread contamination of groundwater arsenic (As) via microbial reduction of As-bearing iron (Fe) minerals in the subsurface results in toxic levels of arsenic above the World Health Organization (WHO) drinking water standard of 10 ug/L. High groundwater arsenic levels are generally found in gray Holocene aquifers whereas orange-sanded Pleistocene aquifers are typically a safer, lower As alternative. In the Red River Delta of Vietnam and elsewhere, Pleistocene aquifers can also have elevated arsenic levels, often due to increased groundwater pumping from the growing Hanoi area drawing high As water from Holocene aquifers, or from reduction induced by advected groundwater and organic carbon from the Red River. To determine which factors threaten the Pleistocene aquifers, we critically examine the hydrological and geochemical factors that could influence arsenic levels in the area. Exploiting an asymmetry in the region just south of Hanoi, yearlong spatiotemporal measurements of dissolved arsenic levels reveals a paradox between a Pleistocene aquifer site in Yen My (west bank) with higher As concentrations than a Holocene site in Van Duc (east bank). We monitor the influence of local and regional hydrology via water table measurements, stable water isotopes and conservative anion concentrations linked to the release of aqueous As. Preliminary x-ray absorption spectroscopy (XAS) data point to As(V)/arsenic sulfide minerals in Yen My versus As(III) minerals in Van Duc. Coupled to hydrology, downcore Fe Extended X-Ray Absorption Fine Structure (EXAFS) and As X-ray Absorption Near Edge Structure (XANES) stratigraphy and spatiotemporal dissolved organic carbon data serve to narrow down the possible sources of carbon and reductive processes that affect As speciation and transport. Overall, understanding sources that endanger the Pleistocene aquifers may elucidate important As cycling mechanisms at play that threatens water quality for

Chromosome analysis of arsenic affected cattle

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S. Shekhar

2014-10-01

Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

Geomicrobial interactions with arsenic and antimony

Science.gov (United States)

Oremland, Ronald S.

2015-01-01

Although arsenic and antimony are generally toxic to life, some microorganisms exist that can metabolize certain forms of these elements. Some can use arsenite or stibnite as potential or sole energy sources, whereas others can use aresenate and antimonite (as was discovered only recently) as terminal electron acceptors. Still other microbes can metabolize arsenic and antimony compounds to detoxify them. These reactions are important from a geomicrobial standpoint because they indicate that a number of microbes contribute to arsenic and antimony mobilization or immobilization in the environment and play a role in arsenic and antimony cycles. Recent reviews include five on prokaryotes and arsenic metabolism, a review with an arsenic perspective on biomining, and a series on environmental antimony, including one about antimony and its interaction with microbiota.

Arsenic exposure, urinary arsenic speciation, and peripheral vascular disease in blackfoot disease-hyperendemic villages in Taiwan

International Nuclear Information System (INIS)

Tseng, C.-H.; Huang, Y.-K.; Huang, Y.-L.; Chung, C.-J.; Yang, M.-H.; Chen, C.-J.; Hsueh, Y.-M.

2005-01-01

Long-term exposure to ingested inorganic arsenic is associated with peripheral vascular disease (PVD) in the blackfoot disease (BFD)-hyperendemic area in Taiwan. This study further examined the interaction between arsenic exposure and urinary arsenic speciation on the risk of PVD. A total of 479 (220 men and 259 women) adults residing in the BFD-hyperendemic area were studied. Doppler ultrasound was used to diagnose PVD. Arsenic exposure was estimated by an index of cumulative arsenic exposure (CAE). Urinary levels of total arsenic, inorganic arsenite (As III ) and arsenate (As V ), monomethylarsonic acid (MMA V ), and dimethylarsinic acid (DMA V ) were determined. Primary methylation index [PMI = MMA V /(As III + As V )] and secondary methylation index (SMI = DMA V /MMA V ) were calculated. The association between PVD and urinary arsenic parameters was evaluated with consideration of the interaction with CAE and the confounding effects of age, sex, body mass index, total cholesterol, triglycerides, cigarette smoking, and alcohol consumption. Results showed that aging was associated with a diminishing capacity to methylate inorganic arsenic and women possessed a more efficient arsenic methylation capacity than men did. PVD risk increased with a higher CAE and a lower capacity to methylate arsenic to DMA V . The multivariate-adjusted odds ratios for CAE of 0, 0.1-15.4, and >15.4 mg/L x year were 1.00, 3.41 (0.74-15.78), and 4.62 (0.96-22.21), respectively (P 6.93, PMI > 1.77 and SMI > 6.93, PMI > 1.77 and SMI ≤ 6.93, and PMI ≤ 1.77 and SMI ≤ 6.93 were 1.00, 2.93 (0.90-9.52), 2.85 (1.05-7.73), and 3.60 (1.12-11.56), respectively (P V have a higher risk of developing PVD in the BFD-hyperendemic area in Taiwan

Source of arsenic-bearing pyrite in southwestern Vermont, USA: Sulfur isotope evidence

Energy Technology Data Exchange (ETDEWEB)

Mango, Helen, E-mail: helen.mango@castleton.edu [Department of Natural Sciences, Castleton State College, 233 South Street, Castleton, VT 05735 (United States); Ryan, Peter, E-mail: pryan@middlebury.edu [Department of Geology, Middlebury College, 276 Bicentennial Way, Middlebury, VT 05753 (United States)

2015-02-01

Arsenic-bearing pyrite is the source of arsenic in groundwater produced in late Cambrian and Ordovician gray and black slates and phyllites in the Taconic region of southwestern Vermont, USA. The aim of this study is to analyze the sulfur isotopic composition of this pyrite and determine if a relationship exists between pyrite δ{sup 34}S and arsenic content. Pyrite occurs in both sedimentary/diagenetic (bedding-parallel layers and framboids) and low-grade metamorphic (porphyroblast) forms, and contains up to > 2000 ppm As. The sulfur isotopic composition of arsenic-bearing pyrite ranges from − 5.2‰ to 63‰. In the marine environment, the sulfur in sedimentary pyrite becomes increasingly enriched in {sup 34}S as the geochemical environment becomes increasingly anoxic. There is a positive correlation between δ{sup 34}S and arsenic content in the Taconic pyrite, suggesting that uptake of arsenic by pyrite increased as the environment became more reducing. This increased anoxia may have been due to a rise in sea level and/or tectonic activity during the late Cambrian and Ordovician. Low-grade metamorphism appears to have little effect on sulfur isotope composition, but does correlate with lower arsenic content in pyrite. New groundwater wells drilled in this region should therefore avoid gray and black slates and phyllites that contain sedimentary/diagenetic pyrite with heavy δ{sup 34}S values. - Highlights: • Pyrite is the source of arsenic in groundwater in the Taconic region of Vermont, USA. • As-bearing pyrite δ{sup 34}S = – 5.2 to 63‰ with higher {sup 34}S as environment becomes more anoxic. • High sea level, tectonic activity create anoxia, with incorporation of As into pyrite. • New wells should avoid slate/phyllite containing sedimentary pyrite with heavy δ{sup 34}S.

Source of arsenic-bearing pyrite in southwestern Vermont, USA: Sulfur isotope evidence

International Nuclear Information System (INIS)

Mango, Helen; Ryan, Peter

2015-01-01

Arsenic-bearing pyrite is the source of arsenic in groundwater produced in late Cambrian and Ordovician gray and black slates and phyllites in the Taconic region of southwestern Vermont, USA. The aim of this study is to analyze the sulfur isotopic composition of this pyrite and determine if a relationship exists between pyrite δ 34 S and arsenic content. Pyrite occurs in both sedimentary/diagenetic (bedding-parallel layers and framboids) and low-grade metamorphic (porphyroblast) forms, and contains up to > 2000 ppm As. The sulfur isotopic composition of arsenic-bearing pyrite ranges from − 5.2‰ to 63‰. In the marine environment, the sulfur in sedimentary pyrite becomes increasingly enriched in 34 S as the geochemical environment becomes increasingly anoxic. There is a positive correlation between δ 34 S and arsenic content in the Taconic pyrite, suggesting that uptake of arsenic by pyrite increased as the environment became more reducing. This increased anoxia may have been due to a rise in sea level and/or tectonic activity during the late Cambrian and Ordovician. Low-grade metamorphism appears to have little effect on sulfur isotope composition, but does correlate with lower arsenic content in pyrite. New groundwater wells drilled in this region should therefore avoid gray and black slates and phyllites that contain sedimentary/diagenetic pyrite with heavy δ 34 S values. - Highlights: • Pyrite is the source of arsenic in groundwater in the Taconic region of Vermont, USA. • As-bearing pyrite δ 34 S = – 5.2 to 63‰ with higher 34 S as environment becomes more anoxic. • High sea level, tectonic activity create anoxia, with incorporation of As into pyrite. • New wells should avoid slate/phyllite containing sedimentary pyrite with heavy δ 34 S

Engineered coryneform bacteria as a bio-tool for arsenic remediation.

Science.gov (United States)

Villadangos, Almudena F; Ordóñez, Efrén; Pedre, Brandán; Messens, Joris; Gil, Jose A; Mateos, Luis M

2014-12-01

Despite current remediation efforts, arsenic contamination in water sources is still a major health problem, highlighting the need for new approaches. In this work, strains of the nonpathogenic and highly arsenic-resistant bacterium Corynebacterium glutamicum were used as inexpensive tools to accumulate inorganic arsenic, either as arsenate (As(V)) or arsenite (As(III)) species. The assays made use of "resting cells" from these strains, which were assessed under well-established conditions and compared with C. glutamicum background controls. The two mutant As(V)-accumulating strains were those used in a previously published study: (i) ArsC1/C2, in which the gene/s encoding the mycothiol-dependent arsenate reductases is/are disrupted, and (ii) MshA/C mutants unable to produce mycothiol, the low molecular weight thiol essential for arsenate reduction. The As(III)-accumulating strains were either those lacking the arsenite permease activities (Acr3-1 and Acr3-2) needed in As(III) release or recombinant strains overexpressing the aquaglyceroporin genes (glpF) from Corynebacterium diphtheriae or Streptomyces coelicolor, to improve As(III) uptake. Both genetically modified strains accumulated 30-fold more As(V) and 15-fold more As(III) than the controls. The arsenic resistance of the modified strains was inversely proportional to their metal accumulation ability. Our results provide the basis for investigations into the use of these modified C. glutamicum strains as a new bio-tool in arsenic remediation efforts.

Arsenic in Drinking Water—A Global Environmental Problem

Science.gov (United States)

Shaofen Wang, Joanna; Wai, Chien M.

2004-02-01

Arsenic contamination of groundwater is a global environmental problem affecting a large number of populations, especially in developing countries. The "blackfoot disease"that occurred in Taiwan more than half of a century ago was attributed to drinking arsenic-contaminated water from deep wells containing high concentrations of the trivalent arsenite species. Similar arsenic poisoning cases were reported later in Chinese Inner Mongolia, Bangladesh, and India—all related to drinking groundwater contaminated with arsenic. The maximum contaminant level (MCL) of arsenic in drinking water has been changed recently by the U.S. EPA from 50 ppb to 10 ppb; the compliance date is January 2006. This article summarizes documented global arsenic contamination problems, the regulatory controversy regarding MCL of arsenic in drinking water, and available technologies for removing arsenic from contaminated waters. Methods for analyzing total arsenic and arsenic species in water are also described.

[Study of relationship between arsenic methylation and skin lesion in a population with long-term high arsenic exposure].

Science.gov (United States)

Su, Liqin; Cheng, Yibin; Lin, Shaobin; Wu, Chuanye

2007-05-01

To investigate the difference of arsenic metabolism in populations with long-term high arsenic exposure and explore the relationship between arsenic metabolism diversity and skin lesion. 327 residents in an arsenic polluted village were voluntarily enrolled in this study. Questionnaire survey and medical examination were carried out to learn basic information and detect skin lesions. Urinary inorganic and methylated arsenic were speciated by high performance liquid chromatography combined with hydride-generation atomic fluorescence spectrometry. Total arsenic concentration in hair was determined with DDC-Ag method. Hair arsenic content of studied polutions was generally high, but no significant difference were found among the studied four groups. MMA and DMA concentration in urine increased with studied polution age, and were positively related with skin lesion grade. The relative proportion of MMA in serious skin lesion group was significantly higher than in other 3 groups, while DMA/MMA ratio was significantly lower than control and mild group. The relative proportion of MMA was positively related with skin lesion grade, DMA/ MMA ratio was negatively related with skin lesion grade. Males could have higher arsenic cumulation and lower methylation capacity than those of females. The population of above 40 years old may have higher methylation capacity than those of adults below 40yeas old. Smokers and drinkers seemed lower methylation capacity than those of non-smokers and non-drinkers respectively. The methylation of arsenic could affect by several factors, including age gender, smoking and drinking. Arsenic methylation copacity mey be associated with skin lesion induced by arsenic exposure.

Arsenic speciation analysis of urine samples from individuals living in an arsenic-contaminated area in Bangladesh.

Science.gov (United States)

Hata, Akihisa; Yamanaka, Kenzo; Habib, Mohamed Ahsan; Endo, Yoko; Fujitani, Noboru; Endo, Ginji

2012-05-01

Chronic inorganic arsenic (iAs) exposure currently affects tens of millions of people worldwide. To accurately determine the proportion of urinary arsenic metabolites in residents continuously exposed to iAs, we performed arsenic speciation analysis of the urine of these individuals and determined whether a correlation exists between the concentration of iAs in drinking water and the urinary arsenic species content. The subjects were 165 married couples who had lived in the Pabna District in Bangladesh for more than 5 years. Arsenic species were measured using high-performance liquid chromatography and inductively coupled plasma mass spectrometry. The median iAs concentration in drinking water was 55 μgAs/L (range 47.9-153.4 μgAs/L), respectively. No arsenobetaine or arsenocholine was detected. The concentrations of the 4 urinary arsenic species were significantly and linearly related to each other. The urinary concentrations of total arsenic and each species were significantly correlated with the iAs concentration of drinking water. All urinary arsenic species are well correlated with each other and with iAs in drinking water. The most significant linear relationship existed between the iAs concentration in drinking water and urinary iAs + MMA concentration. From these results, combined with the effects of seafood ingestion, the best biomarker of iAs exposure is urinary iAs + MMA concentration.

Exiguobacterium mediated arsenic removal and its protective effect against arsenic induced toxicity and oxidative damage in freshwater fish, Channa striata

Directory of Open Access Journals (Sweden)

Neha Pandey

2015-01-01

Full Text Available Arsenic is a toxic metalloid existing widely in the environment, and its removal from contaminated water has become a global challenge. The use of bacteria in this regard finds a promising solution. In the present study, Exiguobacterium sp. As-9, which is an arsenic resistant bacterium, was selected with respect to its arsenic removal efficiency. Quantification of arsenic in the water treated with bacterium showed that Exiguobacterium efficiently removed up to 99% of arsenic in less than 20 h. In order to reveal the possible effect of this bacterium in removal of arsenic from water and protecting fishes from the detrimental effects of arsenic, we initiated a range of studies on fresh water fish, Channa striata. It was observed that the fishes introduced into bacteria treated water displayed no symptoms of arsenic toxicity which was marked by a decreased oxidative damage, whereas the fishes exposed to arsenic revealed a significant (p < 0.05 increase in the oxidative stress together with the elevated levels of malondialdehyde. Determination of the bioaccumulation of arsenic in the liver tissues of C. striata using hydride generation atomic absorption spectrophotometry (HG-AAS revealed an increased As(III accumulation in the fishes exposed to arsenic whereas the arsenic level in the control and bacteria treated fishes were found below the detectable limit. In conclusion, this study presents the strategies of bacterial arsenic removal with possible directions for future research.

Microbial transformations of arsenic: perspectives for biological removal of arsenic from water

NARCIS (Netherlands)

Cavalca, L.; Corsini, A.; Zaccheo, P.; Andreoni, V.; Muyzer, G.

2013-01-01

Arsenic is present in many environments and is released by various natural processes and anthropogenic actions. Although arsenic is recognized to cause a wide range of adverse health effects in humans, diverse bacteria can metabolize it by detoxification and energy conservation reactions. This

Impaired ovarian functions in arsenic-treated freshwater fish, Colisa fasciatus (bl. and sch. )

Energy Technology Data Exchange (ETDEWEB)

Shukla, J.P.; Pandey, K.

1984-01-01

Arsenic(III) oxide (2.0 mg/l) after 15 and 30 days exposure, and 14.0 mg/l concentration after 15 days exposure, produced no marked histological alteration in the ovary of Colisa fasciatus during its mature phase, whereas 14.0 mg/l arsenic(III) oxide concentration after 30 days exposure decreased the development of oocyte (II and III stage), reduced the number and diameter of nucleoli and increased the number of atretic follicles. The possible mechanism for these alterations is discussed.

Immunotoxicological effects of inorganic arsenic on gilthead seabream (Sparus aurata L.)

Energy Technology Data Exchange (ETDEWEB)

Guardiola, F.A.; Gónzalez-Párraga, M.P.; Cuesta, A. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Meseguer, J. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Martínez, S.; Martínez-Sánchez, M.J.; Pérez-Sirvent, C. [Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Esteban, M.A., E-mail: aesteban@um.es [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain)

2013-06-15

Highlights: •Short exposure to arsenic increases the hepato-somatic index and produces histopathological alterations in the liver. •Arsenic is bioaccumulated in the liver of gilthead seabream but no in the muscle. •Arsenic-exposure affects the innate immune system in the gilthead seabream. •Ten days of exposure to As enhances the immune parameters. -- Abstract: Arsenic (As) has been associated with multitude of animal and human health problems; however, its impact on host immune system has not been extensively investigated. In fish, there are very few works on the potential risks or problems associated to the presence of arsenic. In the present study we have evaluated the effects of exposure (30 days) to sub-lethal concentrations of arsenic (5 μM As{sub 2}O{sub 3}) in the teleost fish gilthead seabream (Sparus aurata), with special emphasis in the innate immune response. The arsenic concentration was determined using atomic fluorescence spectrometry (AFS) in liver and muscle of exposed fish showing As accumulation in the liver after 30 days of exposure. The hepatosomatic index was increased at significant extent after 10 days but returned to control values after 30 days of exposure. Histological alterations in the liver were observed including hypertrophy, vacuolization and cell-death processes. Focusing on the immunological response, the humoral immune parameters (seric IgM, complement and peroxidase activities) were no affected to a statistically significant extent. Regarding the cellular innate parameters, head-kidney leucocyte peroxidase, respiratory burst and phagocytic activities were significantly increased after 10 days of exposition compared to the control fish. Overall, As-exposure in the seabream affects the immune system. How this might interfere with fish biology, aquaculture management or human consumers warrants further investigations. This paper describes, for the first time, the immunotoxicological effects of arsenic exposure in the

Linking Arsenic Metabolism and Toxic Effects

Science.gov (United States)

Although arsenic has been long recognized as a toxicant and a carcinogen, the molecular basis for few of its adverse effects are well understood. Like other metalloids, arsenic undergoes extensive metabolism involving oxidation state changes and formation of methyl-arsenic bonds ...

Arsenic geochemistry of groundwater in Southeast Asia.

Science.gov (United States)

Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

2011-12-01

The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 μg·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 μg·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries.

Electrochemical arsenic remediation for rural Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Addy, Susan Amrose [Univ. of California, Berkeley, CA (United States)

2008-01-01

Arsenic in drinking water is a major public health problem threatening the lives of over 140 million people worldwide. In Bangladesh alone, up to 57 million people drink arsenic-laden water from shallow wells. ElectroChemical Arsenic Remediation(ECAR) overcomes many of the obstacles that plague current technologies and can be used affordably and on a small-scale, allowing for rapid dissemination into Bangladesh to address this arsenic crisis. In this work, ECAR was shown to effectively reduce 550 - 580 μg=L arsenic (including both As[III]and As[V]in a 1:1 ratio) to below the WHO recommended maximum limit of 10 μg=L in synthetic Bangladesh groundwater containing relevant concentrations of competitive ions such as phosphate, silicate, and bicarbonate. Arsenic removal capacity was found to be approximately constant within certain ranges of current density, but was found to change substantially between ranges. In order of decreasing arsenic removal capacity, the pattern was: 0.02 mA=cm²> 0.07 mA=cm²> 0.30 - 1.1 mA=cm²> 5.0 - 100 mA=cm². Current processing time was found to effect arsenic removal capacity independent of either charge density or current density. Electrode polarization studies showed no passivation of the electrode in the tested range (up to current density 10 mA=cm²) and ruled out oxygen evolution as the cause of decreasing removal capacity with current density. Simple settling and decantation required approximately 3 days to achieve arsenic removal comparable to filtration with a 0.1 mu m membrane. X-ray Absorption Spectroscopy (XAS) showed that (1) there is no significant difference in the arsenic removal mechanism of ECAR during operation at different current densities and (2) the arsenic removal mechanism in ECAR is consistent with arsenate adsorption onto a homogenous Fe(III)oxyhydroxide similar in structure to 2-line ferrihydrite. ECAR effectively reduced high arsenic concentrations (100

ARSENIC RESEARCH AT GWERD

Science.gov (United States)

Abstract - The presentation will summarize the arsenic research program at the Ground Water & Ecosystems Restoration Division of the National Risk Management Research Laboratory of USEPA. Topics include use of permeable reactive barriers for in situ arsenic remediation in ground...

Granulated Bog Iron Ores as Sorbents in Passive (BioRemediation Systems for Arsenic Removal

Directory of Open Access Journals (Sweden)

Klaudia Debiec

2018-03-01

Full Text Available The main element of PbRS (passive (bioremediation systems are sorbents, which act as natural filters retaining heavy metals and carriers of microorganisms involved in water treatment. Thus, the effectiveness of PbRS is determined by the quality of the (adsorbents, which should be stable under various environmental conditions, have a wide range of applications and be non-toxic to (microorganisms used in these systems. Our previous studies showed that bog iron ores (BIOs meet these requirements. However, further investigation of the physical and chemical parameters of BIOs under environmental conditions is required before their large-scale application in PbRS. The aim of this study was (i to investigate the ability of granulated BIOs (gBIOs to remove arsenic from various types of contaminated waters, and (ii to estimate the application potential of gBIOs in technologies dedicated to water treatment. These studies were conducted on synthetic solutions of arsenic and environmental samples of arsenic contaminated water using a set of adsorption columns filled with gBIOs. The experiments performed in a static system revealed that gBIOs are appropriate arsenic and zinc adsorbent. Dynamic adsorption studies confirmed these results and showed, that the actual sorption efficiency of gBIOs depends on the adsorbate concentration and is directly proportional to them. Desorption analysis showed that As-loaded gBIOs are characterized by high chemical stability and they may be reused for the (adsorption of other elements, i.e., zinc. It was also shown that gBIOs may be used for remediation of both highly oxygenated waters and groundwater or settling ponds, where the oxygen level is low, as both forms of inorganic arsenic (arsenate and arsenite were effectively removed. Arsenic concentration after treatment was <100 μg/L, which is below the limit for industrial water.

Granulated bog iron ores as sorbents in passive (bio)remediation systems for arsenic removal

Science.gov (United States)

Debiec, Klaudia; Rzepa, Grzegorz; Bajda, Tomasz; Uhrynowski, Witold; Sklodowska, Aleksandra; Krzysztoforski, Jan; Drewniak, Lukasz

2018-03-01

The main element of PbRS (passive (bio)remediation systems) are sorbents, which act as natural filters retaining heavy metals and carriers of microorganisms involved in water treatment. Thus, the effectiveness of PbRS is determined by the quality of the (ad)sorbents, which should be stable under various environmental conditions, have a wide range of applications and be non-toxic to (micro)organisms used in these systems. Our previous studies showed that bog iron ores (BIOs) meet these requirements. However, further investigation of the physical and chemical parameters of BIOs under environmental conditions is required before their large-scale application in PbRS. The aim of this study was (i) to investigate the ability of granulated BIOs (gBIOs) to remove arsenic from various types of contaminated waters, and (ii) to estimate the application potential of gBIOs in technologies dedicated to water treatment. These studies were conducted on synthetic solutions of arsenic and environmental samples of arsenic contaminated water using a set of adsorption columns filled with gBIOs. The experiments performed in a static system revealed that gBIOs are appropriate arsenic and zinc adsorbent. Dynamic adsorption studies confirmed these results and showed that the actual sorption efficiency of gBIOs depends on the adsorbate concentration and is directly proportional to them. Desorption analysis showed that As-loaded gBIOs are characterized by high chemical stability and they may be reused for the (ad)sorption of other elements, i.e. zinc. It was also shown that gBIOs may be used for remediation of both highly oxygenated waters and groundwater or settling ponds, where the oxygen level is low, as both forms of inorganic arsenic (arsenate and arsenite) were effectively removed. Arsenic concentration after treatment was <100 µg/L, which is below the limit for industrial water.

Arsenic mobilization and immobilization in paddy soils

Science.gov (United States)

Kappler, A.; Hohmann, C.; Zhu, Y. G.; Morin, G.

2010-05-01

Arsenic is oftentimes of geogenic origin and in many cases bound to iron(III) minerals. Iron(III)-reducing bacteria can harvest energy by coupling the oxidation of organic or inorganic electron donors to the reduction of Fe(III). This process leads either to dissolution of Fe(III)-containing minerals and thus to a release of the arsenic into the environment or to secondary Fe-mineral formation and immobilisation of arsenic. Additionally, aerobic and anaerobic iron(II)-oxidizing bacteria have the potential to co-precipitate or sorb arsenic during iron(II) oxidation at neutral pH that is usually followed by iron(III) mineral precipitation. We are currently investigating arsenic immobilization by Fe(III)-reducing bacteria and arsenic co-precipitation and immobilization by anaerobic iron(II)-oxidizing bacteria in batch, microcosm and rice pot experiments. Co-precipitation batch experiments with pure cultures of nitrate-dependent Fe(II)-oxidizing bacteria are used to quantify the amount of arsenic that can be immobilized during microbial iron mineral precipitation, to identify the minerals formed and to analyze the arsenic binding environment in the precipitates. Microcosm and rice pot experiments are set-up with arsenic-contaminated rice paddy soil. The microorganisms (either the native microbial population or the soil amended with the nitrate-dependent iron(II)-oxidizing Acidovorax sp. strain BoFeN1) are stimulated either with iron(II), nitrate, or oxygen. Dissolved and solid-phase arsenic and iron are quantified. Iron and arsenic speciation and redox state in batch and microcosm experiments are determined by LC-ICP-MS and synchrotron-based methods (EXAFS, XANES).

Impaired arsenic metabolism in children during weaning

International Nuclear Information System (INIS)

Faengstroem, Britta; Hamadani, Jena; Nermell, Barbro; Grander, Margaretha; Palm, Brita; Vahter, Marie

2009-01-01

Background: Methylation of inorganic arsenic (iAs) via one-carbon metabolism is a susceptibility factor for a range of arsenic-related health effects, but there is no data on the importance of arsenic metabolism for effects on child development. Aim: To elucidate the development of arsenic metabolism in early childhood. Methods: We measured iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA), the metabolites of iAs, in spot urine samples of 2400 children at 18 months of age. The children were born to women participating in a population-based longitudinal study of arsenic effects on pregnancy outcomes and child development, carried out in Matlab, a rural area in Bangladesh with a wide range of arsenic concentrations in drinking water. Arsenic metabolism was evaluated in relation to age, sex, anthropometry, socio-economic status and arsenic exposure. Results: Arsenic concentrations in child urine (median 34 μg/L, range 2.4-940 μg/L), adjusted to average specific gravity of 1.009 g/mL, were considerably higher than that measured at 3 months of age, but lower than that in maternal urine. Child urine contained on average 12% iAs, 9.4% MA and 78% DMA, which implies a marked change in metabolite pattern since infancy. In particular, there was a marked increase in urinary %MA, which has been associated with increased risk of health effects. Conclusion: The arsenic metabolite pattern in urine of children at 18 months of age in rural Bangladesh indicates a marked decrease in arsenic methylation efficiency during weaning.

Investigation into mummies from the Atacama Desert, Chile: Did they suffer from arsenic poisoning?

Energy Technology Data Exchange (ETDEWEB)

Krupp, Eva M.; Leidich, Patrick; Raab, Andrea; Ouypornkochagorn, Sairoong; Feldmann, Joerg, E-mail: e.krupp@abdn.ac.uk [TESLA, University of Aberdeen, Aberdeen, Scotland (United Kingdom); Kemp, Helen; Meier-Augenstein, Wolfram [Stable Isotope Laboratory, James Hutton Institute, Invergowrie, Dundee (United Kingdom); Stegen, Susana; Quirolo, Fabrizio; Hubbe, Mark [Universidad del Norte, Antofagasta (Chile)

2011-07-01

Full text: the foothills of the Andes. Despite its hostility, people have lived here for thousands of years, manifested by the discovery of mummies which are from Pre-Columbian times and can be as old as 1500 years. In addition, the water of the few oasis and rivers of this region can be highly contaminated by arsenic, which originates from geogenic sources. The work presented here aims on the question whether the people that lived in this region were exposed to arsenic in their drinking water. Arsenic is known for its acute toxicity when administered in high doses, but also its carcinogenic impact even in very low doses, and the WHO standard for maximum As concentration in drinking water was recently reduced to 10 {mu}g/L. Arsenic exposure in people can be monitored in keratogenous material like hair, nails and skin. In addition, arsenic speciation in these tissues can be used to determine whether the As was metabolised in the body, enabling the differentiation from ingestion of As versus external contamination by either As present in the soil or any cosmetic/preservative treatment of the body prior or after death. The Atacama people traditionally buried their dead in shallow graves in the high regions of the altiplano, and the dry and cold climate set on a natural mummification, which leads to the fact that a huge amount of well preserved mummified remains can be found in the desert. Here, we investigate hair, skin and fingernail samples of up to 10 Mummies dated to approx. 500 years of age, for arsenic concentration and speciation of As, focusing on the determination whether these people may have suffered from As exposure through drinking water. Water sources around the find spots of the mummies were investigated for As concentration, and significant variations can be found for different water sources. In addition to arsenic speciation analysis using XANES and HPLC-ICPMS, stable isotope analysis was performed for C,N,O and H, revealing the source of food these

Investigation into mummies from the Atacama Desert, Chile: Did they suffer from arsenic poisoning?

International Nuclear Information System (INIS)

Krupp, Eva M.; Leidich, Patrick; Raab, Andrea; Ouypornkochagorn, Sairoong; Feldmann, Joerg; Kemp, Helen; Meier-Augenstein, Wolfram; Stegen, Susana; Quirolo, Fabrizio; Hubbe, Mark

2011-01-01

Full text: the foothills of the Andes. Despite its hostility, people have lived here for thousands of years, manifested by the discovery of mummies which are from Pre-Columbian times and can be as old as 1500 years. In addition, the water of the few oasis and rivers of this region can be highly contaminated by arsenic, which originates from geogenic sources. The work presented here aims on the question whether the people that lived in this region were exposed to arsenic in their drinking water. Arsenic is known for its acute toxicity when administered in high doses, but also its carcinogenic impact even in very low doses, and the WHO standard for maximum As concentration in drinking water was recently reduced to 10 μg/L. Arsenic exposure in people can be monitored in keratogenous material like hair, nails and skin. In addition, arsenic speciation in these tissues can be used to determine whether the As was metabolised in the body, enabling the differentiation from ingestion of As versus external contamination by either As present in the soil or any cosmetic/preservative treatment of the body prior or after death. The Atacama people traditionally buried their dead in shallow graves in the high regions of the altiplano, and the dry and cold climate set on a natural mummification, which leads to the fact that a huge amount of well preserved mummified remains can be found in the desert. Here, we investigate hair, skin and fingernail samples of up to 10 Mummies dated to approx. 500 years of age, for arsenic concentration and speciation of As, focusing on the determination whether these people may have suffered from As exposure through drinking water. Water sources around the find spots of the mummies were investigated for As concentration, and significant variations can be found for different water sources. In addition to arsenic speciation analysis using XANES and HPLC-ICPMS, stable isotope analysis was performed for C,N,O and H, revealing the source of food these

Hijacking membrane transporters for arsenic phytoextraction

Science.gov (United States)

LeBlanc, Melissa S.; McKinney, Elizabeth C.; Meagher, Richard B.; Smith, Aaron P.

2012-01-01

Arsenic is a toxic metalloid and recognized carcinogen. Arsenate and arsenite are the most common arsenic species available for uptake by plants. As an inorganic phosphate (Pi) analog, arsenate is acquired by plant roots through endogenous Pi transport systems. Inside the cell, arsenate is reduced to the thiol-reactive form arsenite. Glutathione (GSH)-conjugates of arsenite may be extruded from the cell or sequestered in vacuoles by members of the ATP-binding cassette (ABC) family of transporters. In the present study we sought to enhance both plant arsenic uptake through Pi transporter overexpression, and plant arsenic tolerance through ABC transporter overexpression. We demonstrate that Arabidopsis thaliana plants overexpressing the high-affinity Pi transporter family members, AtPht1;1 or AtPht1;7, are hypersensitive to arsenate due to increased arsenate uptake. These plants do not exhibit increased sensitivity to arsenite. Co-overexpression of the yeast ABC transporter YCF1 in combination with AtPht1;1 or AtPht1;7 suppresses the arsenate-sensitive phenotype while further enhancing arsenic uptake. Taken together, our results support an arsenic transport mechanism in which arsenate uptake is increased through Pi transporter overexpression, and arsenic tolerance is enhanced through YCF1-mediated vacuolar sequestration. This work substantiates the viability of coupling enhanced uptake and vacuolar sequestration as a means for developing a prototypical engineered arsenic hyperaccumulator. PMID:23108027

Assessment of global industrial-age anthropogenic arsenic contamination.

Science.gov (United States)

Han, Fengxiang X; Su, Yi; Monts, David L; Plodinec, M John; Banin, Amos; Triplett, Glover E

2003-09-01

Arsenic, a carcinogenic trace element, threatens not only the health of millions of humans and other living organisms, but also global sustainability. We present here, for the first time, the global industrial-age cumulative anthropogenic arsenic production and its potential accumulation and risks in the environment. In 2000, the world cumulative industrial-age anthropogenic arsenic production was 4.53 million tonnes. The world-wide coal and petroleum industries accounted for 46% of global annual gross arsenic production, and their overall contribution to industrial-age gross arsenic production was 27% in 2000. Global industrial-age anthropogenic As sources (as As cumulative production) follow the order: As mining production>As generated from coal>As generated from petroleum. The potential industrial-age anthropogenic arsenic input in world arable surface in 2000 was 2.18 mg arsenic kg(-1), which is 1.2 times that in the lithosphere. The development of substitute materials for arsenic applications in the agricultural and forestry industries and controls of arsenic emissions from the coal industry may be possible strategies to significantly decrease arsenic pollution sources and dissipation rates into the environment.

ARSENIC REMOVAL BY PHYTOFILTRATION AND SILICON TREATMENT : A POTENTIAL SOLUTION FOR LOWERING ARSENIC CONCENTRATIONS IN FOOD CROPS

OpenAIRE

Sandhi, Arifin

2017-01-01

Use of arsenic-rich groundwater for crop irrigation can increase the arsenic (As) content in food crops and act as a carcinogen, compromising human health. Using aquatic plant based phytofiltration is a potential eco-technique for removing arsenic from water. The aquatic moss species Warnstorfia fluitans grows naturally in mining areas in northern Sweden, where high concentrations of arsenic occur in lakes and rivers. This species was selected as a model for field, climate chamber and greenho...

Arsenic and human health effects: A review.

Science.gov (United States)

Abdul, Khaja Shameem Mohammed; Jayasinghe, Sudheera Sammanthi; Chandana, Ediriweera P S; Jayasumana, Channa; De Silva, P Mangala C S

2015-11-01

Arsenic (As) is ubiquitous in nature and humans being exposed to arsenic via atmospheric air, ground water and food sources are certain. Major sources of arsenic contamination could be either through geological or via anthropogenic activities. In physiological individuals, organ system is described as group of organs that transact collectively and associate with other systems for conventional body functions. Arsenic has been associated with persuading a variety of complications in body organ systems: integumentary, nervous, respiratory, cardiovascular, hematopoietic, immune, endocrine, hepatic, renal, reproductive system and development. In this review, we outline the effects of arsenic on the human body with a main focus on assorted organ systems with respective disease conditions. Additionally, underlying mechanisms of disease development in each organ system due to arsenic have also been explored. Strikingly, arsenic has been able to induce epigenetic changes (in utero) and genetic mutations (a leading cause of cancer) in the body. Occurrence of various arsenic induced health effects involving emerging areas such as epigenetics and cancer along with their respective mechanisms are also briefly discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

Role of complex organic arsenicals in food in aggregate exposure to arsenic

Science.gov (United States)

For much of the world’s population, food is the major source of exposure to arsenic. Exposure to this non-essential metalloid at relatively low levels has been linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important ...

In situ chemical fixation of arsenic-contaminated soils: Anexperimental study

Energy Technology Data Exchange (ETDEWEB)

Yang, Li; Donahoe, Rona J.; Redwine, James C.

2007-03-27

procedure (TCLP) and EPA Method 1312 [USEPA.Method 1312:synthetic precipitation leaching procedure. Test methods for evaluatingsolid waste, physical/chemical methods. 3rd ed. Washington, DC: U.S.Environmental Protection Agency, Office of Solid Waste. U.S. GovernmentPrinting Office; 1994]synthetic precipitation leaching procedure(SPLP).Both FW and BH soils showed significant decreases in arsenicleachability for all three treatment solutions, compared to untreatedsoil. While soils treated with solution (3) showed the best results withsubsequent TCLP sequential leaching, SPLP sequential leaching of treatedsoils indicated that lowest arsenic mobility was obtained using treatmentsolution (1). Treatment solution (1) with only FeSO4 is considered thebest choice for remediation of arsenic-contaminated soil because SPLPsequential leaching better simulates natural weathering. Analysis oftreated soils produced no evidence of newly-formed arsenic-bearing phasesin either soil after treatment. Sequential chemical extractions oftreated soils indicate that surface complexation of arsenic on ferrichydroxide is the major mechanism for the fixation process.

ARSENIC INTERACTION WITH IRON (II, III) HYDROXYCARBONATE GREEN RUST: IMPLICATIONS FOR ARSENIC REMEDIATION

Science.gov (United States)

Zerovalent iron is being used in permeable reactive barriers (PRBs) to remediate groundwater arsenic contamination. Iron(II, III) hydroxycarbonate green rust is a major corrosion product of zerovalent iron under anaerobic conditions. The interaction between arsenic and this green...

Preparation of iron-impregnated granular activated carbon for arsenic removal from drinking water

International Nuclear Information System (INIS)

Chang Qigang; Lin Wei; Ying Weichi

2010-01-01

Granular activated carbon (GAC) was impregnated with iron through a new multi-step procedure using ferrous chloride as the precursor for removing arsenic from drinking water. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis demonstrated that the impregnated iron was distributed evenly on the internal surface of the GAC. Impregnated iron formed nano-size particles, and existed in both crystalline (akaganeite) and amorphous iron forms. Iron-impregnated GACs (Fe-GACs) were treated with sodium hydroxide to stabilize iron in GAC and impregnated iron was found very stable at the common pH range in water treatments. Synthetic arsenate-contaminated drinking water was used in isotherm tests to evaluate arsenic adsorption capacities and iron use efficiencies of Fe-GACs with iron contents ranging from 1.64% to 12.13% (by weight). Nonlinear regression was used to obtain unbiased estimates of Langmuir model parameters. The arsenic adsorption capacity of Fe-GAC increased significantly with impregnated iron up to 4.22% and then decreased with more impregnated iron. Fe-GACs synthesized in this study exhibited higher affinity for arsenate as compared with references in literature and shows great potential for real implementations.

A Review of Groundwater Arsenic Contamination in Bangladesh: The Millennium Development Goal Era and Beyond.

Science.gov (United States)

Yunus, Fakir Md; Khan, Safayet; Chowdhury, Priyanka; Milton, Abul Hasnat; Hussain, Sumaira; Rahman, Mahfuzar

2016-02-15

Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs) under four domains: (1) extent of arsenic contamination; (2) health consequences; (3) mitigation and technologies and (4) future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population's access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies.

Distribution and speciation of arsenic by transplacental and early life exposure to inorganic arsenic in offspring rats.

Science.gov (United States)

Xi, Shuhua; Jin, Yaping; Lv, Xiuqiang; Sun, Guifan

2010-04-01

The amount of arsenic compounds was determined in the liver and brain of pups and in breast milk in the pup's stomach in relation to the route of exposure: transplacental, breast milk, or drinking water. Forty-eight pregnant rats were randomly divided into four groups, each group was given free access to drinking water that contained 0, 10, 50, and 100 mg/L NaAsO(2) from gestation day 6 (GD 6) until postnatal day 42 (PND 42). Once pups were weaned, they started to drink the same arsenic-containing water as the dams. Contents of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and trimethylarsenic acid (TMA) in livers and brains of the pups on PND 0, 15, 28, and 42 and breast milk taken from the pup's stomach on PND 0 and 15 were detected using the hydride generation atomic absorption spectroscopy method. Concentrations of iAs, MMA, and DMA in the breast milk, the brain, and the liver of the pups increased with the concentration of arsenic in drinking water on PND 0, 15, 28, and 42. Compared to the liver or brain, breast milk had the lowest arsenic concentrations. There was a significant decrease in the levels of arsenic species on PND 15 compared to PND 0, 28, or 42. It was confirmed that arsenic species can pass through the placental barrier from dams to offspring and across the blood-brain barrier in the pups, and breast milk from dams exposed to arsenic in drinking water contains less arsenic than the liver and brain of pups.

Toxic Substances Portal- Arsenic

Science.gov (United States)

... is found at low levels in breast milk. top How can families reduce their risk for exposure to arsenic? If you use arsenic-treated wood in home projects, you should wear dust masks, gloves, and protective clothing to decrease exposure to sawdust. ...

Arsenic

Science.gov (United States)

... for drinking-water quality Chemical hazards in drinking-water: arsenic Evaluations of the Joint FAO/WHO Expert Committee ... Africa Americas South-East Asia Europe Eastern Mediterranean Western ...

Effect of Fluoride on Arsenic Uptake from Arsenic-Contaminated Groundwater using Pteris vittata L.

Science.gov (United States)

Zhao, Junying; Guo, Huaming; Ma, Jie; Shen, Zhaoli

2015-01-01

High-arsenic groundwater in inland basins usually contains high concentrations of fluoride. In the present study, the effects of fluoride on arsenic uptake by Pteris vittata and on arsenic transformation in growth media were investigated under greenhouse conditions. After P. vittata was hydroponically exposed to 66.8 μM As (V) in the presence of 1.05 mM F- in the form of NaF, KF, or NaF+KF for 10 d, no visible toxicity symptoms were observed, and there were not significant differences in the dry biomass among the four treatments. The results showed that P. vittata tolerated F- concentrations as high as 1.05 mM but did not accumulate fluoride in their own tissues. Arsenic uptake was inhibited in the presence of 1.05 mM F-. However, in hydroponic batches with 60 μM As (III) or 65 μM As (V), it was found that 210.6 and 316.0 μM F(-) promoted arsenic uptake. As(III) was oxidized to As(V) in the growth media in the presence and absence of plants, and F- had no effect on the rate of As(III) transformation. These experiments demonstrated that P. vittata was a good candidate to remediate arsenic-contaminated groundwater in the presence of fluoride. Our results can be used to develop strategies to remediate As-F-contaminated water using P. vittata.

A calibration method for proposed XRF measurements of arsenic and selenium in nail clippings

International Nuclear Information System (INIS)

Gherase, Mihai R; Fleming, David E B

2011-01-01

A calibration method for proposed x-ray fluorescence (XRF) measurements of arsenic and selenium in nail clippings is demonstrated. Phantom nail clippings were produced from a whole nail phantom (0.7 mm thickness, 25 x 25 mm 2 area) and contained equal concentrations of arsenic and selenium ranging from 0 to 20 μg g -1 in increments of 5 μg g -1 . The phantom nail clippings were then grouped in samples of five different masses: 20, 40, 60, 80 and 100 mg for each concentration. Experimental x-ray spectra were acquired for each of the sample masses using a portable x-ray tube and a detector unit. Calibration lines (XRF signal in a number of counts versus stoichiometric elemental concentration) were produced for each of the two elements. A semi-empirical relationship between the mass of the nail phantoms (m) and the slope of the calibration line (s) was determined separately for arsenic and selenium. Using this calibration method, one can estimate elemental concentrations and their uncertainties from the XRF spectra of human nail clippings. (note)

Arsenic in tube well water in Bangladesh: health and economic impacts and implications for arsenic mitigation.

Science.gov (United States)

Flanagan, Sara V; Johnston, Richard B; Zheng, Yan

2012-11-01

A national drinking water quality survey conducted in 2009 furnished data that were used to make an updated estimate of chronic arsenic exposure in Bangladesh. About 20 million and 45 million people were found to be exposed to concentrations above the national standard of 50 µg/L and the World Health Organization's guideline value of 10 µg/L, respectively. From the updated exposure data and all-cause mortality hazard ratios based on local epidemiological studies, it was estimated that arsenic exposures to concentrations > 50 µg/L and 10-50 µg/L account for an annual 24,000 and perhaps as many as 19,000 adult deaths in the country, respectively. Exposure varies widely in the 64 districts; among adults, arsenic-related deaths account for 0-15% of all deaths. An arsenic-related mortality rate of 1 in every 16 adult deaths could represent an economic burden of 13 billion United States dollars (US$) in lost productivity alone over the next 20 years. Arsenic mitigation should follow a two-tiered approach: (i) prioritizing provision of safe water to an estimated 5 million people exposed to > 200 µg/L arsenic, and (ii) building local arsenic testing capacity. The effectiveness of such an approach was demonstrated during the United Nations Children's Fund 2006-2011 country programme, which provided safe water to arsenic-contaminated areas at a cost of US$ 11 per capita. National scale-up of such an approach would cost a few hundred million US dollars but would improve the health and productivity of the population, especially in future generations.

Arsenic removal by manganese greensand filters

Energy Technology Data Exchange (ETDEWEB)

Phommavong, T. [Saskatchewan Environment, Regina (Canada); Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

1994-12-31

Some of the small communities in Saskatchewan are expected to have difficulty complying with the new maximum acceptable concentration (MAC) of 25 {micro}g/L for arsenic. A test column was set up in the laboratory to study the removal of arsenic from the potable water using oxidation with KMnO{sub 4}, followed by manganese greensand filtration. Tests were run using water from the tap having a background arsenic concentration of <0.5 {micro}g/L and iron concentration in the range of 0.02 to 0.77 mg/L. The test water was spiked with arsenic and iron. Results showed that 61 % to 98% of arsenic can be removed from the potable water by oxidation with KMnO{sub 4} followed by manganese greensand filtration.

Maternal Arsenic Exposure, Arsenic Methylation Efficiency, and Birth Outcomes in the Biomarkers of Exposure to ARsenic (BEAR) Pregnancy Cohort in Mexico

Science.gov (United States)

Laine, Jessica E.; Bailey, Kathryn A.; Rubio-Andrade, Marisela; Olshan, Andrew F.; Smeester, Lisa; Drobná, Zuzana; Herring, Amy H.; Stýblo, Miroslav; García-Vargas, Gonzalo G.

2014-01-01

Background: Exposure to inorganic arsenic (iAs) from drinking water is a global public health problem, yet much remains unknown about the extent of exposure in susceptible populations. Objectives: We aimed to establish the Biomarkers of Exposure to ARsenic (BEAR) prospective pregnancy cohort in Gómez Palacio, Mexico, to better understand the effects of iAs exposure on pregnant women and their children. Methods: Two hundred pregnant women were recruited for this study. Concentrations of iAs in drinking water (DW-iAs) and maternal urinary concentrations of iAs and its monomethylated and dimethylated metabolites (MMAs and DMAs, respectively) were determined. Birth outcomes were analyzed for their relationship to DW-iAs and to the concentrations and proportions of maternal urinary arsenicals. Results: DW-iAs for the study subjects ranged from iAs that exceeded the World Health Organization’s recommended guideline of 10 μg As/L. DW-iAs was significantly associated with the sum of the urinary arsenicals (U-tAs). Maternal urinary concentrations of MMAs were negatively associated with newborn birth weight and gestational age. Maternal urinary concentrations of iAs were associated with lower mean gestational age and newborn length. Conclusions: Biomonitoring results demonstrate that pregnant women in Gómez Palacio are exposed to potentially harmful levels of DW-iAs. The data support a relationship between iAs metabolism in pregnant women and adverse birth outcomes. The results underscore the risks associated with iAs exposure in vulnerable populations. Citation: Laine JE, Bailey KA, Rubio-Andrade M, Olshan AF, Smeester L, Drobná Z, Herring AH, Stýblo M, García-Vargas GG, Fry RC. 2015. Maternal arsenic exposure, arsenic methylation efficiency, and birth outcomes in the Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort in Mexico. Environ Health Perspect 123:186–192; http://dx.doi.org/10.1289/ehp.1307476 PMID:25325819

Inhibition of insulin-dependent glucose uptake by trivalent arsenicals: possible mechanism of arsenic-induced diabetes

International Nuclear Information System (INIS)

Walton, Felecia S.; Harmon, Anne W.; Paul, David S.; Drobna, Zuzana; Patel, Yashomati M.; Styblo, Miroslav

2004-01-01

Chronic exposures to inorganic arsenic (iAs) have been associated with increased incidence of noninsulin (type-2)-dependent diabetes mellitus. Although mechanisms by which iAs induces diabetes have not been identified, the clinical symptoms of the disease indicate that iAs or its metabolites interfere with insulin-stimulated signal transduction pathway or with critical steps in glucose metabolism. We have examined effects of iAs and methylated arsenicals that contain trivalent or pentavalent arsenic on glucose uptake by 3T3-L1 adipocytes. Treatment with inorganic and methylated pentavalent arsenicals (up to 1 mM) had little or no effect on either basal or insulin-stimulated glucose uptake. In contrast, trivalent arsenicals, arsenite (iAs III ), methylarsine oxide (MAs III O), and iododimethylarsine (DMAs III O) inhibited insulin-stimulated glucose uptake in a concentration-dependent manner. Subtoxic concentrations of iAs III (20 μM), MAs III O (1 μM), or DMAs III I (2 μM) decreased insulin-stimulated glucose uptake by 35-45%. Basal glucose uptake was significantly inhibited only by cytotoxic concentrations of iAs III or MAs III O. Examination of the components of the insulin-stimulated signal transduction pathway showed that all trivalent arsenicals suppressed expression and possibly phosphorylation of protein kinase B (PKB/Akt). The concentration of an insulin-responsive glucose transporter (GLUT4) was significantly lower in the membrane region of 3T3-L1 adipocytes treated with trivalent arsenicals as compared with untreated cells. These results suggest that trivalent arsenicals inhibit insulin-stimulated glucose uptake by interfering with the PKB/Akt-dependent mobilization of GLUT4 transporters in adipocytes. This mechanism may be, in part, responsible for the development of type-2 diabetes in individuals chronically exposed to iAs

Arsenic, microbes and contaminated aquifers

Science.gov (United States)

Oremland, Ronald S.; Stolz, John F.

2005-01-01

The health of tens of millions of people world-wide is at risk from drinking arsenic-contaminated well water. In most cases this arsenic occurs naturally within the sub-surface aquifers, rather than being derived from identifiable point sources of pollution. The mobilization of arsenic into the aqueous phase is the first crucial step in a process that eventually leads to human arsenicosis. Increasing evidence suggests that this is a microbiological phenomenon.

ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

Directory of Open Access Journals (Sweden)

Palas Roy

2013-01-01

Full Text Available High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Multivariate data analysis was done with the collected groundwater samples from the 132 tubewells of this contaminated region shows that three variable parameters are significantly related with the arsenic. Based on these relationships, a multiple linear regression model has been developed that estimated the arsenic contamination by measuring such three predictor parameters of the groundwater variables in the contaminated aquifer. This model could also be a suggestive tool while designing the arsenic removal scheme for any affected groundwater.

Synthesis and characterization of arsenic-doped cysteine-capped thoria-based nanoparticles

International Nuclear Information System (INIS)

Pereira, F. J.; Díez, M. T.; Aller, A. J.

2013-01-01

Thoria materials have been largely used in the nuclear industry. Nonetheless, fluorescent thoria-based nanoparticles provide additional properties to be applied in other fields. Thoria-based nanoparticles, with and without arsenic and cysteine, were prepared in 1,2-ethanediol aqueous solutions by a simple precipitation procedure. The synthesized thoria-based nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (ED-XRS), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy and fluorescence microscopy. The presence of arsenic and cysteine, as well as the use of a thermal treatment facilitated fluorescence emission of the thoria-based nanoparticles. Arsenic-doped and cysteine-capped thoria-based nanoparticles prepared in 2.5 M 1,2-ethanediol solutions and treated at 348 K showed small crystallite sizes and strong fluorescence. However, thoria nanoparticles subjected to a thermal treatment at 873 K also produced strong fluorescence with a very narrow size distribution and much smaller crystallite sizes, 5 nm being the average size as shown by XRD and TEM. The XRD data indicated that, even after doping of arsenic in the crystal lattice of ThO 2 , the samples treated at 873 K were phase pure with the fluorite cubic structure. The Raman and FT-IR spectra shown the most characteristics vibrational peaks of cysteine together with other peaks related to the bonds of this molecule to thoria and arsenic when present

Distribution of Arsenic and Risk Assessment of Activities on Soccer Pitches Irrigated with Arsenic-Contaminated Water

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Nadia Martínez-Villegas

2018-05-01

Full Text Available The aim of this research was to estimate the risk of human exposure to arsenic due to sporting activities in a private soccer club in Mexico, where arsenic-contaminated water was regularly used for irrigation. For this purpose, the total concentration in the topsoil was considered for risk assessment. This was accomplished through three main objectives: (1 measuring arsenic concentrations in irrigation water and irrigated soils, (2 determining arsenic spatial distribution in shallow soils with Geographical Information Systems (GIS using geostatistical analysis, and (3 collecting field and survey data to develop a risk assessment calculation for soccer activities in the soccer club. The results showed that the average arsenic concentrations in shallow soils (138.1 mg/kg were 6.2 times higher than the Mexican threshold for domestic soils (22 mg/kg. Furthermore, dermal contact between exposed users and contaminated soils accounted for a maximum carcinogenic risk value of 1.8 × 10−5, which is one order of magnitude higher than the recommended risk value, while arsenic concentrations in the irrigation water were higher (6 mg/L than the WHO’s permissible threshold in drinking water, explaining the contamination of soils after irrigation. To the best of our knowledge, this is the first risk study regarding dermal contact with arsenic following regular grass irrigation with contaminated water in soccer pitches.

Certain cases of poisoning by arsenic

Energy Technology Data Exchange (ETDEWEB)

Cristol, P; Fourcade, J; Ravoire, J; Bezenech, C

1939-05-01

Cases of acute and chronic poisoning by arsenic are reported. Diffuse pains, angor, edema of the limbs and genitals, complicated by heptic insufficiency and chronic bronchitis were determined in a subject having lived near an industrial plant processing arseniferous ores for several years. The plant emitted several hundred kg of finely dispersed arsenic oxide daily which settled on forage and vegetables. Symptoms of poisoning by arsenic were also detected in cattle in the same area. The installation of Cottrell type dust separators has helped to suppress the arsenic oxide emissions.

Urinary arsenic speciation profile in ethnic group of the Atacama desert (Chile) exposed to variable arsenic levels in drinking water.

Science.gov (United States)

Yáñez, Jorge; Mansilla, Héctor D; Santander, I Paola; Fierro, Vladimir; Cornejo, Lorena; Barnes, Ramón M; Amarasiriwardena, Dulasiri

2015-01-01

Ethnic groups from the Atacama Desert (known as Atacameños) have been exposed to natural arsenic pollution for over 5000 years. This work presents an integral study that characterizes arsenic species in water used for human consumption. It also describes the metabolism and arsenic elimination through urine in a chronically exposed population in northern Chile. In this region, water contained total arsenic concentrations up to 1250 μg L(-1), which was almost exclusively As(V). It is also important that this water was ingested directly from natural water sources without any treatment. The ingested arsenic was extensively methylated. In urine 93% of the arsenic was found as methylated arsenic species, such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. The original ingested inorganic species [As(V)], represent less than 1% of the total urinary arsenic. Methylation activity among individuals can be assessed by measuring primary [inorganic As/methylated As] and secondary methylation [MMA/DMA] indexes. Both methylation indexes were 0.06, indicating a high biological converting capability of As(V) into MMA and then MMA into DMA, compared with the control population and other arsenic exposed populations previously reported.

Arsenic burden survey among refuse incinerator workers

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Chao Chung-Liang

2005-01-01

Full Text Available Background: Incinerator workers are not considered to have arsenic overexposure although they have the risk of overexposure to other heavy metals. Aim: To examine the relationship between arsenic burden and risk of occupational exposure in employees working at a municipal refuse incinerator by determining the concentrations of arsenic in the blood and urine. Settings and Design: The workers were divided into three groups based on their probability of contact with combustion-generated residues, namely Group 1: indirect contact, Group 2: direct contact and Group 3: no contact. Healthy age- and sex-matched residents living in the vicinity were enrolled as the control group. Materials and Methods: Heavy metal concentrations were measured by atomic absorption spectrophotometer. Downstream rivers and drinking water of the residents were examined for environmental arsenic pollution. A questionnaire survey concerning the contact history of arsenic was simultaneously conducted. Statistical analysis: Non-parametric tests, cross-tabulation and multinomial logistic regression. Results: This study recruited 122 incinerator workers. The urine and blood arsenic concentrations as well as incidences of overexposure were significantly higher in the workers than in control subjects. The workers who had indirect or no contact with combustion-generated residues had significantly higher blood arsenic level. Arsenic contact history could not explain the difference. Airborne and waterborne arsenic pollution were not detected. Conclusion: Incinerator workers run the risk of being exposed to arsenic pollution, especially those who have incomplete protection in the workplace even though they only have indirect or no contact with combustion-generated pollutants.

Long-term consequences of arsenic poisoning during infancy due to contaminated milk powder

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Grandjean Philippe

2006-10-01

Full Text Available Abstract Arsenic toxicity is a global health problem affecting many millions of people. The main source of exposure is drinking water contaminated by natural geological sources. Current risk assessment is based on the recognized carcinogenicity of arsenic, but neurotoxic risks have been overlooked. In 1955, an outbreak of arsenic poisoning occurred among Japanese infants, with more than 100 deaths. The source was contaminated milk powder produced by the Morinaga company. Detailed accounts of the Morinaga dried milk poisoning were published in Japanese only, and an overview of this poisoning incident and its long-term consequences is therefore presented. From analyses available, the arsenic concentration in milk made from the Morinaga milk powder is calculated to be about 4–7 mg/L, corresponding to daily doses slightly above 500 μg/kg body weight. Lower exposures would result from using diluted milk. Clinical poisoning cases occurred after a few weeks of exposure, with a total dose of about 60 mg. This experience provides clear-cut evidence for hazard assessment of the developmental neurotoxicity. At the present time, more than 600 surviving victims, now in their 50s, have been reported to suffer from severe sequelae, such as mental retardation, neurological diseases, and other disabilities. Along with more recent epidemiological studies of children with environmental arsenic exposures, the data amply demonstrate the need to consider neurotoxicity as a key concern in risk assessment of inorganic arsenic exposure.

Cytotoxic effects of S-(dimethylarsino)-glutathione: A putative intermediate metabolite of inorganic arsenicals

International Nuclear Information System (INIS)

Hirano, Seishiro; Kobayashi, Yayoi

2006-01-01

Glutathione (GSH) plays an important role in the metabolism of arsenite and arsenate by generating arsenic-glutathione complexes. Although dimethylarsinic acid (DMA V ) is the major metabolite of inorganic arsenicals (iAs) in urine, it is not clear how DMA V is produced from iAs. In the present study we report that S-(dimethylarsino)-glutathione (DMA III (SG)), a putative precursor of dimethylarsinic acid DMA V , was unstable in the culture medium without excess GSH and generated volatile substances which were highly cytotoxic for both rat heart microvascular endothelial cells and HL60, a human leukemia cell line. Cytotoxicity of DMA III (SG) was higher than that of iAs and its LC 5 value was calculated to be 7.8 μM in the endothelial cells. To our surprise DMA III (SG) effectively killed cells in the neighbor wells of the same multi-well dish, indicating that volatile toxic compounds generated from DMA III (SG) in the culture medium. High performance lipid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) analyses suggested that the freshly generated volatile compounds dissolved into aqueous solution and formed an unstable arsenic compound and the unstable compound was further converted to DMA V . These results suggested that DMA III (SG) exerts its cytotoxicity by generating volatile arsenicals and is implicated in the metabolic conversion of inorganic arsenicals into DMA V , a major final metabolite of inorganic arsenicals in most mammals

Is arsenic biotransformation a detoxification mechanism for microorganisms?

International Nuclear Information System (INIS)

Rahman, M. Azizur; Hassler, Christel

2014-01-01

Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As V , which is thermodynamically stable in oxic waters, and As III , which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As V , biotransform it to As III , then biomethylate it to methylarsenic (MetAs) forms. Although As III is more toxic than As V , As III is much more easily excreted from the cells than As V . Therefore, majority of researchers consider the reduction of As V to As III as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA V , dimethylarsonate; DMA V , and trimethylarsenic oxide; TMAO V ) and trimethylarsine (TMAO III ). However, biomethylation by microorganisms also produces monomethylarsenite (MMA III ) and dimethylarsenite (DMA III ), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data

Containing arsenic-enriched groundwater tracing lead isotopic compositions of common arsenical pesticides in a coastal Maine watershed

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Ayuso, Robert A.; Foley, Nora K.; Robinson, Glipin R.; Colvin, A.S.; Lipfert, G.; Reeve, A.S.

2006-01-01

Arsenical pesticides and herbicides were extensively used on apple, blueberry, and potato crops in New England during the first half of the twentieth century. Lead arsenate was the most heavily used arsenical pesticide until it was officially banned. Lead arsenate, calcium arsenate, and sodium arsenate have similar Pb isotope compositions: 208Pb207Pb = 2.3839-2.4722, and 206Pb207Pb = 1.1035-1.2010. Other arsenical pesticides such as copper acetoarsenite (Paris green), methyl arsonic acid and methane arsonic acid, as well as arsanilic acid are widely variable in isotope composition. Although a complete understanding of the effects of historical use of arsenical pesticides is not available, initial studies indicate that arsenic and lead concentrations in stream sediments in New England are higher in agricultural areas that intensely used arsenical pesticides than in other areas. The Pb isotope compositions of pesticides partially overlap values of stream sediments from areas with the most extensive agricultural use. The lingering effects of arsenical pesticide use were tested in a detailed geochemical and isotopic study of soil profiles from a watershed containing arsenic-enriched ground water in coastal Maine. Acid-leach compositions of the soils represent lead adsorbed to mineral surfaces or held in soluble minerals (Fe- and Mn-hydroxides, carbonate, and some micaceous minerals), whereas residue compositions likely reflect bedrock compositions. The soil profiles contain labile Pb (acid-leach) showing a moderate range in 206Pb 207Pb (1.1870-1.2069), and 208Pb207Pb (2.4519-2.4876). Isotope values vary as a function of depth: the lowest Pb isotope ratios (e.g.,208Pb206Pb) representing labile lead are in the uppermost soil horizons. Lead contents decrease with depth in the soil profiles. Arsenic contents show no clear trend with depth. A multi-component mixing scheme that included lead from the local parent rock (Penobscot Formation), lead derived from combustion of

Chronic exposure to arsenic in drinking water can lead to resistance to antimonial drugs in a mouse model of visceral leishmaniasis.

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Perry, Meghan R; Wyllie, Susan; Raab, Andrea; Feldmann, Joerg; Fairlamb, Alan H

2013-12-03

The Indian subcontinent is the only region where arsenic contamination of drinking water coexists with widespread resistance to antimonial drugs that are used to treat the parasitic disease visceral leishmaniasis. We have previously proposed that selection for parasite resistance within visceral leishmaniasis patients who have been exposed to trivalent arsenic results in cross-resistance to the related metalloid antimony, present in the pentavalent state as a complex in drugs such as sodium stibogluconate (Pentostam) and meglumine antimonate (Glucantime). To test this hypothesis, Leishmania donovani was serially passaged in mice exposed to arsenic in drinking water at environmentally relevant levels (10 or 100 ppm). Arsenic accumulation in organs and other tissues was proportional to the level of exposure and similar to that previously reported in human liver biopsies. After five monthly passages in mice exposed to arsenic, isolated parasites were found to be completely refractory to 500 μg · mL(-1) Pentostam compared with the control passage group (38.5 μg · mL(-1)) cultured in vitro in mouse peritoneal macrophages. Reassessment of resistant parasites following further passage for 4 mo in mice without arsenic exposure showed that resistance was stable. Treatment of infected mice with Pentostam confirmed that resistance observed in vitro also occurred in vivo. We conclude that arsenic contamination may have played a significant role in the development of Leishmania antimonial resistance in Bihar because inadequate treatment with antimonial drugs is not exclusive to India, whereas widespread antimonial resistance is.

First-principles studies of di-arsenic interstitial and its implications for arsenic-interstitial diffusion in crystalline silicon

International Nuclear Information System (INIS)

Kim, Yonghyun; Kirichenko, Taras A.; Kong, Ning; Larson, Larry; Banerjee, Sanjay K.

2007-01-01

We propose new structural configurations and novel diffusion mechanisms for neutral di-arsenic interstitial (As 2 I 2 ) in silicon with a first-principle density functional theory simulation within the generalized gradient approximation. With an assumption of excess silicon interstitials and high arsenic concentrations, neutral As 2 I 2 is expected to be favorable and mobile with low-migration barrier. Moreover, because the diffusion barrier of arsenic interstitial pairs (AsI) is very low ( 2 I 2 can be easily formed and likely intermediate stage of larger arsenic interstitial clusters

Inorganic arsenic levels in baby rice are of concern

International Nuclear Information System (INIS)

Meharg, Andrew A.; Sun, Guoxin; Williams, Paul N.; Adomako, Eureka; Deacon, Claire; Zhu, Yong-Guan; Feldmann, Joerg; Raab, Andrea

2008-01-01

Inorganic arsenic is a chronic exposure carcinogen. Analysis of UK baby rice revealed a median inorganic arsenic content (n = 17) of 0.11 mg/kg. By plotting inorganic arsenic against total arsenic, it was found that inorganic concentrations increased linearly up to 0.25 mg/kg total arsenic, then plateaued at 0.16 mg/kg at higher total arsenic concentrations. Inorganic arsenic intake by babies (4-12 months) was considered with respect to current dietary ingestion regulations. It was found that 35% of the baby rice samples analysed would be illegal for sale in China which has regulatory limit of 0.15 mg/kg inorganic arsenic. EU and US food regulations on arsenic are non-existent. When baby inorganic arsenic intake from rice was considered, median consumption (expressed as μg/kg/d) was higher than drinking water maximum exposures predicted for adults in these regions when water intake was expressed on a bodyweight basis. - Median consumption of organic arsenic levels for UK babies from baby rice is above threshold considered safe

Chronic arsenic poisoning following ayurvedic medication.

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Pinto, Benzeeta; Goyal, Palvi; Flora, S J S; Gill, K D; Singh, Surjit

2014-12-01

Ayurveda, Indian traditional system of medicine, is practiced commonly in South East Asia and in many parts of the world. Many ayurvedic drugs contain heavy metals and may lead to metal toxicity. Of these, chronic lead poisoning is the most common. Chronic arsenic poisoning following the use of ayurvedic medication, though reported, is rare. We describe three patients who presented with features of chronic arsenic poisoning following prolonged ayurvedic medication use. The diagnosis of chronic arsenic poisoning was confirmed by high arsenic levels in the blood, urine, hair, and nails in all the three patients and in ayurvedic drug in two patients. The ayurvedic medication was discontinued and treatment with D-penicillamine started. At 6 months after treatment, blood arsenic levels returned to normal with clinical recovery in all of them. Arsenic poisoning following ayurvedic medication is much less common than lead poisoning, though mineral ayurvedic medicines may lead to it. We used D-penicillamine as chelator and all of them recovered. Whether withdrawal of medication alone or D-penicillamine also played a role in recovery is unclear and needs to be assessed.

Toxic effects of arsenic on Sinorhizobium-Medicago sativa symbiotic interaction

Energy Technology Data Exchange (ETDEWEB)

Pajuelo, Eloisa [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain); Rodriguez-Llorente, Ignacio D. [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain)], E-mail: irodri@us.es; Dary, Mohammed; Palomares, Antonio J. [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain)

2008-07-15

Recently, the Rhizobium-legume symbiotic interaction has been proposed as an interesting tool in bioremediation. However, little is known about the effect of most common contaminants on this process. The phytotoxic effects of arsenic on nodulation of Medicago sativa have been examined in vitro using the highly arsenic resistant and symbiotically effective Sinorhizobium sp. strain MA11. The bacteria were able to grow on plates containing As concentrations as high as 10 mM. Nevertheless, as little as 25-35 {mu}M arsenite produced a 75% decrease in the total number of nodules, due to a 90% reduction in the number of rhizobial infections, as could be determined using the strain MA11 carrying a lacZ reporter gene. This effect was associated to root hair damage and a shorter infective root zone. However, once nodulation was established nodule development seemed to continue normally, although earlier senescence could be observed in nodules of arsenic-grown plants. - First steps of nodulation of alfalfa, in particular infection thread formation, are more sensitive to As than nitrogen fixation due to plant effects.

Role and mechanism of arsenic in regulating angiogenesis.

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Ling-Zhi Liu

Full Text Available Arsenic is a wide spread carcinogen associated with several kinds of cancers including skin, lung, bladder, and liver cancers. Lung is one of the major targets of arsenic exposure. Angiogenesis is the pivotal process during carcinogenesis and chronic pulmonary diseases, but the role and mechanism of arsenic in regulating angiogenesis remain to be elucidated. In this study we show that short time exposure of arsenic induces angiogenesis in both human immortalized lung epithelial cells BEAS-2B and adenocarcinoma cells A549. To study the molecular mechanism of arsenic-inducing angiogenesis, we find that arsenic induces reactive oxygen species (ROS generation, which activates AKT and ERK1/2 signaling pathways and increases the expression of hypoxia-inducible factor 1 (HIF-1 and vascular endothelial growth factor (VEGF. Inhibition of ROS production suppresses angiogenesis by decreasing AKT and ERK activation and HIF-1 expression. Inhibition of ROS, AKT and ERK1/2 signaling pathways is sufficient to attenuate arsenic-inducing angiogenesis. HIF-1 and VEGF are downstream effectors of AKT and ERK1/2 that are required for arsenic-inducing angiogenesis. These results shed light on the mechanism of arsenic in regulating angiogenesis, and are helpful to develop mechanism-based intervention to prevent arsenic-induced carcinogenesis and angiogenesis in the future.

Bacteria, hypertolerant to arsenic in the rocks of an ancient gold mine, and their potential role in dissemination of arsenic pollution

International Nuclear Information System (INIS)

Drewniak, Lukasz; Styczek, Aleksandra; Majder-Lopatka, Malgorzata; Sklodowska, Aleksandra

2008-01-01

The aim of the present study was to find out if bacteria present in ancient gold mine could transform immobilized arsenic into its mobile form and increase its dissemination in the environment. Twenty-two arsenic-hypertolerant cultivable bacterial strains were isolated. No chemolithoautotrophs, which could use arsenite as an electron donor as well as arsenate as an electron acceptor, were identified. Five isolates exhibited hypertolerance to arsenic: up to 500 mM of arsenate. A correlation between the presence of siderophores and high resistance to arsenic was found. The results of this study show that detoxification processes based on arsenate reductase activity might be significant in dissemination of arsenic pollution. It was concluded that the activity of the described heterotrophic bacteria contributes to the mobilization of arsenic in the more toxic As(III) form and a new mechanism of arsenic mobilization from a scorodite was proposed. - The activity of the described heterotrophic bacteria leads to mobilization of arsenic and in this way contributes to the dissemination of arsenic pollution

Small System Use of a Solid Arsenic Oxidizing Media in Place of Chemical Oxidation to Enhance Arsenic Removals

Science.gov (United States)

As part of the USEPA Arsenic Demonstration Program, an arsenic removal adsorptive media treatment system (10 gpm) was installed at Head Start School in Buckeye Lake, Ohio on June 28, 2006. The source water (ground water) contained around 20 µg/L of arsenic, existing predominatel...

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

International Nuclear Information System (INIS)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath

2014-01-01

-induced vascular dysfunction. • Arsenic reduced ACh-induced aortic relaxation but didn’t alter response to SNP and PE. • Arsenic affected aortic NO signalling and production of inflammatory mediators. • Arsenic produced vasculopathic lesions in aorta. • Atorvastatin restored arsenic-induced functional, biochemical and structural changes

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

Energy Technology Data Exchange (ETDEWEB)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath, E-mail: snsarkar1911@rediffmail.com

2014-10-01

-induced vascular dysfunction. • Arsenic reduced ACh-induced aortic relaxation but didn’t alter response to SNP and PE. • Arsenic affected aortic NO signalling and production of inflammatory mediators. • Arsenic produced vasculopathic lesions in aorta. • Atorvastatin restored arsenic-induced functional, biochemical and structural changes.

Arsenic uptake by Lemna minor in hydroponic system.

Science.gov (United States)

Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

2014-01-01

Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

Arsenic species and chemistry in groundwater of southeast Michigan

International Nuclear Information System (INIS)

Kim, M.-J.; Nriagu, Jerome; Haack, Sheridan

2002-01-01

Most of the arsenic detected was arsenite [As(III)]. - Groundwater samples, taken from 73 wells in 10 counties of southeast Michigan in 1997 had arsenic concentrations in the range of 0.5 to 278 μg/l, the average being 29 μg/l. About 12% of these wells had arsenic concentrations that exceeded the current USEPA's maximum contaminant level of 50 μg/l. Most (53-98%) of the arsenic detected was arsenite [As(III)] and other observations supported the arsenic species distribution (low redox potential and DO). In shallow groundwater ( 15 m), the concentration of arsenic is possibly controlled by reductive dissolution of arsenic-rich iron hydroxide/oxyhydroxide and dissolution of arsenic sulfide minerals

Arsenic in groundwater of Licking County, Ohio, 2012—Occurrence and relation to hydrogeology

Science.gov (United States)

Thomas, Mary Ann

2016-02-23

Arsenic concentrations were measured in samples from 168 domestic wells in Licking County, Ohio, to document arsenic concentrations in a wide variety of wells and to identify hydrogeologic factors associated with arsenic concentrations in groundwater. Elevated concentrations of arsenic (greater than 10.0 micrograms per liter [µg/L]) were detected in 12 percent of the wells (about 1 in 8). The maximum arsenic concentration of about 44 µg/L was detected in two wells in the same township.A subset of 102 wells was also sampled for iron, sulfate, manganese, and nitrate, which were used to estimate redox conditions of the groundwater. Elevated arsenic concentrations were detected only in strongly reducing groundwater. Almost 20 percent of the samples with iron concentrations high enough to produce iron staining (greater than 300 µg/L) also had elevated concentrations of arsenic.In groundwater, arsenic primarily occurs as two inorganic species—arsenite and arsenate. Arsenic speciation was determined for a subset of nine samples, and arsenite was the predominant species. Of the two species, arsenite is more difficult to remove from water, and is generally considered to be more toxic to humans.Aquifer and well-construction characteristics were compiled from 99 well logs. Elevated concentrations of arsenic (and iron) were detected in glacial and bedrock aquifers but were more prevalent in glacial aquifers. The reason may be that the glacial deposits typically contain more organic carbon than the Paleozoic bedrock. Organic carbon plays a role in the redox reactions that cause arsenic (and iron) to be released from the aquifer matrix. Arsenic concentrations were not significantly different for different types of bedrock (sandstone, shale, sandstone/shale, or other). However, arsenic concentrations in bedrock wells were correlated with two well-construction characteristics; higher arsenic concentrations in bedrock wells were associated with (1) shorter open intervals and

Spatial patterns of fetal loss and infant death in an arsenic-affected area in Bangladesh

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Streatfield Peter

2010-10-01

Full Text Available Abstract Background Arsenic exposure in pregnancy is associated with adverse pregnancy outcome and infant mortality. Knowledge of the spatial characteristics of the outcomes and their possible link to arsenic exposure are important for planning effective mitigation activities. The aim of this study was to identify spatial and spatiotemporal clustering of fetal loss and infant death, and spatial relationships between high and low clusters of fetal loss and infant death rates and high and low clusters of arsenic concentrations in tube-well water used for drinking. Methods Pregnant women from Matlab, Bangladesh, who used tube-well water for drinking while pregnant between 1991 and 2000, were included in this study. In total 29,134 pregnancies were identified. A spatial scan test was used to identify unique non-random spatial and spatiotemporal clusters of fetal loss and infant death using a retrospective spatial and spatiotemporal permutation and Poisson probability models. Results Two significant clusters of fetal loss and infant death were identified and these clusters remained stable after adjustment for covariates. One cluster of higher rates of fetal loss and infant death was in the vicinity of the Meghna River, and the other cluster of lower rates was in the center of Matlab. The average concentration of arsenic in the water differed between these clusters (319 μg/L for the high cluster and 174 μg/L for the low cluster. The spatial patterns of arsenic concentrations in tube-well water were found to be linked with the adverse pregnancy outcome clusters. In the spatiotemporal analysis, only one high fetal loss and infant death cluster was identified in the same high cluster area obtained from purely spatial analysis. However, the cluster was no longer significant after adjustment for the covariates. Conclusion The finding of this study suggests that given the geographical variation in tube-well water contamination, higher fetal loss and

Arsenic contamination and arsenicosis in China

International Nuclear Information System (INIS)

Sun Guifan

2004-01-01

Arsenicosis is a serious environmental chemical disease in China mainly caused by drinking water from pump wells contaminated by high levels of arsenic. Chronic exposure of humans to high concentrations of arsenic in drinking water is associated with skin lesions, peripheral vascular disease, hypertension, blackfoot disease, and high risk of cancers. Lead by the Ministry of Health of China, we carried out a research about arsenicosis in China recently. Areas contaminated with arsenic from drinking water are determined by 10% pump well water sample method while areas from burning coal are determined by existing data. Two epidemic areas of Shanxi Province and Inner Mongolia are investigated for the distribution of pump wells containing high arsenic. Well water in all the investigated villages of Shanxi Province showed polluted by high arsenic, and the average rate of unsafe pump well water is 52%. In Inner Mongolia, the high percentage of pump wells containing elevated arsenic is found only in a few villages. The average rate of unsafe pump well water is 11%. From our research, we find that new endemic areas are continuously emerging in China. Up to now, epidemic areas of arsenicosis mainly involve eight provinces and 37 counties in China. In the affected areas, the discovery of wells and coal with high levels of arsenic is continuing sporadically, and a similar scattered distribution pattern of patients is also being observed

Groundwater arsenic contamination throughout China.

Science.gov (United States)

Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

2013-08-23

Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

Trace speciation analysis of arsenic in beverages

OpenAIRE

Fajgarová, Aneta

2016-01-01

The aim of this bachelor thesis was to determine the toxicologically important arsenic species in beverages (beer, wine and apple juice) with minimal sample preparation. Determination of arsenic species was performed by selective hydride generation of arsenic hydrides with cryogenic collection under liquid nitrogen and detection by atomic absorption spectrometry. In all the samples only inorganic arsenic was found, methyl substituted species were below the limit of detection. The method is su...

ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

OpenAIRE

Palas Roy; Naba Kumar Mondal; Biswajit Das; Kousik Das

2013-01-01

High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India) has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Mul...

Arsenic poisoning of cattle and other domestic animals

Energy Technology Data Exchange (ETDEWEB)

Moxham, J W; Coup, M R

1968-01-01

One hundred and sixty-one incidents of arsenic poisoning in domestic animals were recorded at Ruakura Veterinary Diagnostic Station from 1955 to 1967. Cattle was the animal species most subject to arsenic poisoning. Clincal signs, post-mortem findings and sources of arsenic are given. Arsenic poisoning was more prevalent in younger cattle and during the warmer months of the year. With cattle most incidents were associated with carelessly discarded arsenical compounds, although most deaths occurred when these compounds were deliberately used. In other species, losses were generally caused by the deliberate use of arsenical preparations for dipping, drenching and weed spraying. 10 references, 2 tables.

Arsenic in the environment: enrichments in the Slovenian soils

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Mateja Gosar

2005-12-01

Full Text Available Arsenic, a toxic element with metalloid properties, is found in detectable concentrations in environmental samples. In nature it is enriched in metal (sulphide ore deposits, mainly as arsenides of Cu, Ni and Fe. Arsenic compounds are used mainly in agricultureand forestry as pesticides and herbicides. The ecosystem can be contaminated with arsenic via both natural and anthropogenic sources. Uses of arsenic contaminated water present so far the greatest health hazard. Occurrences of mining related arsenic problems havealso been recorded in many parts of the world.The impact of mining and metallurgic industry with regard to arsenic contents in soils in some potentially contaminated areas in Slovenia is discussed. Enriched contents of arsenic were found in Mežica. Arsenic correlates very well with lead, zinc and other heavymetals which are enriched as a result of long lasting lead production in the area. Also in Celje and Jesenice arsenic has the same distribution pattern as other anthropogenically introduced pollutants. In Idrija there are some slightly arsenic enriched areas, but there is no correlation with mercury, so the origin of arsenic in not clear yet.

Arsenic (Environmental Health Student Portal)

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... Water Waterborne Diseases & Illnesses Water Cycle Water Treatment Videos Games Experiments For Teachers Home Chemicals Arsenic Print this ... human activities, such as mining, farming, and other industries. This can be dangerous, because arsenic is poisonous ...

Napoleon Bonaparte's exposure to arsenic during 1816.

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Leslie, A C; Smith, H

1978-12-11

Analysis of hair from Napoleon showed that he was exposed to considerable amounts of arsenic during 1816. The distribution pattern of the arsenic in the hair is similar to that found after the daily ingestion of excessive amounts of arsenic.

Speciation of arsenic in rice and estimation of daily intake of different arsenic species by Brazilians through rice consumption.

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Batista, Bruno L; Souza, Juliana M O; De Souza, Samuel S; Barbosa, Fernando

2011-07-15

Rice is an important source of essential elements. However, rice may also contain toxic elements such as arsenic. Therefore, in the present study, the concentration of total arsenic and five main chemical species of arsenic (As(3+), As(5+), DMA, MMA and AsB) were evaluated in 44 different rice samples (white, parboiled white, brown, parboiled brown, parboiled organic and organic white) from different Brazilian regions using high-performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The mean level of total arsenic was 222.8 ng g(-1) and the daily intake of inorganic arsenic (the most toxic form) from rice consumption was estimated as 10% of the Provisional Tolerable Daily Intake (PTDI) with a daily ingestion of 88 g of rice. Inorganic arsenic (As(3+), As(5+)) and dimethylarsinic acid (DMA) are the predominant forms in all samples. The percentages of species were 38.7; 39.7; 3.7 and 17.8% for DMA, As(3+), MMA and As(5+), respectively. Moreover, rice samples harvested in the state of Rio Grande do Sul presented more fractions of inorganic arsenic than rice in Minas Gerais or Goiás, which could lead to different risks of arsenic exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

An investigation of the health effects caused by exposure to arsenic from drinking water and coal combustion: arsenic exposure and metabolism.

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Wei, Binggan; Yu, Jiangping; Kong, Chang; Li, Hairong; Yang, Linsheng; Guo, Zhiwei; Cui, Na; Xia, Yajuan; Wu, Kegong

2017-11-01

Few studies have been conducted to compare arsenic exposure, metabolism, and methylation in populations exposed to arsenic in drinking water and from coal combustion. Therefore, arsenic concentrations in the environment and arsenic speciation in the urine of subjects exposed to arsenic as a consequence of coal combustion in a rural area in Shaanxi province (CCA) and in drinking water in a rural area in Inner Mongolia (DWA) were investigated. The mean arsenic concentrations in drinking water, indoor air, and soil in CCA were 4.52 μg/L, 0.03 mg/m 3 , and 14.93 mg/kg, respectively. The mean arsenic concentrations in drinking water and soil in DWA were 144.71 μg/L and 10.19 mg/kg, respectively, while the level in indoor air was lower than the limit of detection. The total daily intakes of arsenic in DWA and CCA were 4.47 and 3.13 μg/day·kg, respectively. The mean urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsenic acid (DMA), and total arsenic (TAs) for subjects with skin lesions in DWA were 50.41, 47.01, 202.66, and 300.08 μg/L. The concentrations for subjects without skin lesions were 49.76, 44.20, 195.60, and 289.56 μg/L, respectively. The %iAs, %MMA, and %DMA in the TAs in the urine of subjects from CCA were 12.24, 14.73, and 73.03%, while the corresponding values from DWA were 17.54, 15.57, and 66.89%, respectively. The subjects in DWA typically had a higher %iAs and %MMA, and a lower %DMA, and primary and secondary methylation index (PMI and SMI) than the subjects in CCA. It was concluded that the arsenic methylation efficiency of subjects in DWA and CCA was significantly influenced by chronic exposure to high levels of arsenic in the environment. The lower PMI and SMI values in DWA revealed lower arsenic methylation capacity due to ingestion of arsenic in drinking water. However, it remained unclear if the differences in arsenic metabolism between the two groups were due to differences in exposure levels

An approach for identification and determination of arsenic species in the extract of kelp.

Science.gov (United States)

Yu, Lee L; Wei, Chao; Zeisler, Rolf; Tong, Junting; Oflaz, Rabia; Bao, Haixia; Wang, Jun

2015-05-01

The National Institute of Standards and Technology is developing a kelp powder standard reference material (SRM) in support of dietary supplement measurements. Edible seaweeds such as kelp and laver consumed as diet or dietary supplement contain tens of mg/kg arsenic. The speciation information of arsenic in the seaweed should be provided because the total arsenic alone does not fully address the safety issue of the dietary supplement as the value assignment is originally intended. The inability to avail all arsenic species for value assignment measurements prevented the certification of arsenic species in the candidate SRM; however, approximately 70 % of total arsenic extracted with a 1:1 volume fraction of methanol:water mixture allowed arsenic speciation values to be assigned to a procedure-defined extract, which may be used for method validation in research to improve upon current extraction and measurement practices. Arsenic species in kelp and laver were identified using electrospray ionization ion trap time of flight mass spectrometry (ESI-IT-TOF). Arsenosugars As(328), As(482), and As(392) were found in the kelp candidate SRM while As(328) and As(482) were found in GBW 08521, a certified reference material (CRM) of laver produced by the National Institute of Metrology of China (NIM). A discovery that the digests of kelp and laver contained only dimethylarsinic acid led to the conclusion that the seaweeds did not contain detectible levels of arsenobetaine, arsenocholine or trimethylarsine oxide that could overlap with the peaks of arsenosugars in the separation. The mean ± s of (5.68 ± 0.28) mg/kg and (13.43 ± 0.31) mg/kg found for As(482) and As(392) in kelp, respectively, using instrumental neutron activation analysis (INAA) demonstrated that value assignment measurement of arsenosugars was possible without arsenosugar calibration standards.

Arsenic concentrations, related environmental factors, and the predicted probability of elevated arsenic in groundwater in Pennsylvania

Science.gov (United States)

Gross, Eliza L.; Low, Dennis J.

2013-01-01

Analytical results for arsenic in water samples from 5,023 wells obtained during 1969–2007 across Pennsylvania were compiled and related to other associated groundwater-quality and environmental factors and used to predict the probability of elevated arsenic concentrations, defined as greater than or equal to 4.0 micrograms per liter (µg/L), in groundwater. Arsenic concentrations of 4.0 µg/L or greater (elevated concentrations) were detected in 18 percent of samples across Pennsylvania; 8 percent of samples had concentrations that equaled or exceeded the U.S. Environmental Protection Agency’s drinking-water maximum contaminant level of 10.0 µg/L. The highest arsenic concentration was 490.0 µg/L.

Phytoremediation of arsenic contaminated soil by Pteris vittata L. II. Effect on arsenic uptake and rice yield.

Science.gov (United States)

Mandal, Asit; Purakayastha, T J; Patra, A K; Sanyal, S K

2012-07-01

A greenhouse experiment evaluated the effect of phytoextraction of arsenic from a contaminated soil by Chinese Brake Fern (Pteris vittata L.) and its subsequent effects on growth and uptake of arsenic by rice (Oryza sativa L.) crop. Pteris vittata was grown for one or two growing cycles of four months each with two phosphate sources, using single super phosphate (SSP) and di-ammonium phosphate (DAP). Rice was grown on phytoextracted soils followed by measurements of biomass yield (grain, straw, and root), arsenic concentration and, uptake by individual plant parts. The biomass yield (grain, straw and rice) of rice was highest in soil phytoextracted with Pteris vittata grown for two cycles and fertilized with diammonium phosphate (DAP). Total arsenic uptake in contaminated soil ranged from 8.2 to 16.9 mg pot(-1) in first growing cycle and 5.5 to 12.0 mg pot(-1) in second growing cycle of Pteris vittata. There was thus a mean reduction of 52% in arsenic content of rice grain after two growing cycle of Pteris vittata and 29% after the one growing cycle. The phytoextraction of arsenic contaminated soil by Pteris vittata was beneficial for growing rice resulted in decreased arsenic content in rice grain of <1 ppm. There was a mean improvement in rice grain yield 14% after two growing cycle and 8% after the one growing cycle of brake fern.

Arsenic in contaminated soil and river sediment

International Nuclear Information System (INIS)

Bombach, G.; Pierra, A.; Klemm, W.

1994-01-01

Different areas in the Erzgebirge mountains are contaminated by high arsenic concentration which is caused by the occurrence of ore and industrial sources. The study showed clearly a high concentration of arsenic in the surface and under soil (A and B horizons) in the Freiberg district. The distribution of the arsenic concentration in the area, the content of water soluble arsenic, the several oxidation states (As 3+ , As 5+ ) and the bonding types have been analyzed. (orig.)

Stable, fertile, high polyhydroxyalkanoate producing plants and methods of producing them

Energy Technology Data Exchange (ETDEWEB)

Bohmert-Tatarev, Karen; McAvoy, Susan; Peoples, Oliver P.; Snell, Kristi D.

2015-08-04

Transgenic plants that produce high levels of polyhydroxybutyrate and methods of producing them are provided. In a preferred embodiment the transgenic plants are produced using plastid transformation technologies and utilize genes which are codon optimized. Stably transformed plants able to produce greater than 10% dwt PHS in tissues are also provided.

Arsenic Remediation by Synthetic and Natural Adsorbents

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Muhammad Saqaf Jagirani

2017-06-01

Full Text Available The contagion of toxic metals in water is a serious environmental and health concern and threatening problem worldwide. Particularly arsenic contamination in ground water has became great dilemma in the earlier decades. With advent in research for arsenic remediation, standard of drinking water is improving and now reduced to few parts per million (ppm level of arsenic in drinking water sources. However, due to continuous enhancement in environmental pollution, remediation techniques are still needed to achieve the drinking water quality standard. Development of novel and economically feasible removal techniques or materials for selective separation of this toxic specie has been the main focus of research. Several arsenic removal techniques, including membrane separation, coagulation, precipitation, anion exchange have been developed. The aim of this article is to review briefly arsenic chemistry and previous and current available technologies that have been reported various low-cost adsorbents for arsenic removal.

Dietary arsenic consumption and urine arsenic in an endemic population: response to improvement of drinking water quality in a 2-year consecutive study.

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Biswas, Anirban; Deb, Debasree; Ghose, Aloke; Du Laing, Gijs; De Neve, Jan; Santra, Subhas Chandra; Guha Mazumder, Debendra Nath

2014-01-01

We assessed the association between arsenic intake through water and diet, and arsenic levels in first morning-void urine under variable conditions of water contamination. This was done in a 2-year consecutive study in an endemic population. Exposure of arsenic through water and diet was assessed for participants using arsenic-contaminated water (≥50 μg L(-1)) in a first year (group I) and for participants using water lower in arsenic (water in groups I and II males was 7.44 and 0.85 μg kg body wt.(-1) day(-1) (p water were reduced to below 50 μg L(-1) (Indian permissible limit), total arsenic intake and arsenic intake through the water significantly decreased, but arsenic uptake through the diet was found to be not significantly affected. Moreover, it was found that drinking water mainly contributed to variations in urine arsenic concentrations. However, differences between male and female participants also indicate that not only arsenic uptake, but also many physiological factors affect arsenic behavior in the body and its excretion. As total median arsenic exposure still often exceeded 3.0 μg kg body wt.(-1) day(-1) (the permissible lower limit established by the Joint Expert Committee on Food Additives) after installation of the drinking water filters, it can be concluded that supplying the filtered water only may not be sufficient to minimize arsenic availability for an already endemic population.

Arsenic and selenium in microbial metabolism

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Stolz, John F.; Basu, Partha; Santini, Joanne M.; Oremland, Ronald S.

2006-01-01

Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.

Heavy metal, total arsenic, and inorganic arsenic contents of algae food products.

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Almela, C; Algora, S; Benito, V; Clemente, M J; Devesa, V; Súñer, M A; Vélez, D; Montoro, R

2002-02-13

The total arsenic, inorganic arsenic, lead, cadmium, and mercury contents of 18 algae food products currently on sale in Spain were determined. The suitability of the analytical methodologies for this type of matrix was confirmed by evaluating their analytical characteristics. The concentration ranges found for each contaminant, expressed in milligrams per kilogram of dry weight, were as follows: total arsenic, 2.3-141; inorganic arsenic, 0.15-88; lead, mercury, 0.004-0.04. There is currently no legislation in Spain regarding contaminants in algae food products, but some of the samples analyzed revealed Cd and inorganic As levels higher than those permitted by legislation in other countries. Given the high concentrations of inorganic As found in Hizikia fusiforme, a daily consumption of 1.7 g of the product would reach the Provisional Tolerable Weekly Intake recommended by the WHO for an average body weight of 68 kg. A more comprehensive study of the contents and toxicological implications of the inorganic As present in the algae food products currently sold in Spain may be necessary, which might then be the basis for the introduction of specific sales restrictions.

Groundwater arsenic contamination in Bangladesh-21 Years of research.

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Chakraborti, Dipankar; Rahman, Mohammad Mahmudur; Mukherjee, Amitava; Alauddin, Mohammad; Hassan, Manzurul; Dutta, Rathindra Nath; Pati, Shymapada; Mukherjee, Subhash Chandra; Roy, Shibtosh; Quamruzzman, Quazi; Rahman, Mahmuder; Morshed, Salim; Islam, Tanzima; Sorif, Shaharir; Selim, Md; Islam, Md Razaul; Hossain, Md Monower

2015-01-01

Department of Public Health Engineering (DPHE), Bangladesh first identified their groundwater arsenic contamination in 1993. But before the international arsenic conference in Dhaka in February 1998, the problem was not widely accepted. Even in the international arsenic conference in West-Bengal, India in February, 1995, representatives of international agencies in Bangladesh and Bangladesh government attended the conference but they denied the groundwater arsenic contamination in Bangladesh. School of Environmental Studies (SOES), Jadavpur University, Kolkata, India first identified arsenic patient in Bangladesh in 1992 and informed WHO, UNICEF of Bangladesh and Govt. of Bangladesh from April 1994 to August 1995. British Geological Survey (BGS) dug hand tube-wells in Bangladesh in 1980s and early 1990s but they did not test the water for arsenic. Again BGS came back to Bangladesh in 1992 to assess the quality of the water of the tube-wells they installed but they still did not test for arsenic when groundwater arsenic contamination and its health effects in West Bengal in Bengal delta was already published in WHO Bulletin in 1988. From December 1996, SOES in collaboration with Dhaka Community Hospital (DCH), Bangladesh started analyzing hand tube-wells for arsenic from all 64 districts in four geomorphologic regions of Bangladesh. So far over 54,000 tube-well water samples had been analyzed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). From SOES water analysis data at present we could assess status of arsenic groundwater contamination in four geo-morphological regions of Bangladesh and location of possible arsenic safe groundwater. SOES and DCH also made some preliminary work with their medical team to identify patients suffering from arsenic related diseases. SOES further analyzed few thousands biological samples (hair, nail, urine and skin scales) and foodstuffs for arsenic to know arsenic body burden and people sub

Groundwater arsenic in Chimaltenango, Guatemala.

Science.gov (United States)

Lotter, Jason T; Lacey, Steven E; Lopez, Ramon; Socoy Set, Genaro; Khodadoust, Amid P; Erdal, Serap

2014-09-01

In the Municipality of Chimaltenango, Guatemala, we sampled groundwater for total inorganic arsenic. In total, 42 samples were collected from 27 (43.5%) of the 62 wells in the municipality, with sites chosen to achieve spatial representation throughout the municipality. Samples were collected from household faucets used for drinking water, and sent to the USA for analysis. The only site found to have a concentration above the 10 μg/L World Health Organization provisional guideline for arsenic in drinking water was Cerro Alto, where the average concentration was 47.5 μg/L. A health risk assessment based on the arsenic levels found in Cerro Alto showed an increase in noncarcinogenic and carcinogenic risks for residents as a result of consuming groundwater as their primary drinking water source. Using data from the US Geological Survey and our global positioning system data of the sample locations, we found Cerro Alto to be the only site sampled within the tertiary volcanic rock layer, a known source of naturally occurring arsenic. Recommendations were made to reduce the levels of arsenic found in the community's drinking water so that the health risks can be managed.

Low selenium status affects arsenic metabolites in an arsenic exposed population with skin lesions.

Science.gov (United States)

Huang, Zhi; Pei, Qiuling; Sun, Guifan; Zhang, Sichum; Liang, Jiang; Gao, Yi; Zhang, Xinrong

2008-01-01

The antagonistic effects between selenium (Se) and arsenic (As) suggest that low selenium status plays important roles in arsenism development. However, no study has been reported for humans suffering from chronic arsenic exposure with low selenium status. Sixty-three subjects were divided into 2 experimental groups by skin lesions (including hyperkeratosis, depigmentation, and hyperpigmentation). Total urine and serum concentrations of arsenic and selenium were determined by ICP-MS with collision/reaction cell. Arsenic species were analysed by ICP-MS coupled with HPLC. The mean concentration of As in the drinking waters was 41.5 microg/l. The selenium dietary intake for the studied population was 31.7 microg Se/d, and which for the cases and controls were 25.9 and 36.3 microg Se/d, respectively. Compared with the controls, the skin lesions cases had lower selenium concentrations in serum and urine (41.4 vs 49.6 microg/l and 71.0 vs 78.8 microg/l, respectively), higher inorganic arsenic (iAs) in serum (5.2 vs 3.4 microg/l, PiAs in serum and urine (20.2) vs 16.9% and 18.3 vs 14.5%, respectively, PiAs and its inhibition to be biotransformed to DMA occurred in human due to chronic exposure of low selenium status.

Complementary arsenic speciation methods: A review

Energy Technology Data Exchange (ETDEWEB)

Nearing, Michelle M., E-mail: michelle.nearing@rmc.ca; Koch, Iris, E-mail: koch-i@rmc.ca; Reimer, Kenneth J., E-mail: reimer-k@rmc.ca

2014-09-01

The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

Complementary arsenic speciation methods: A review

International Nuclear Information System (INIS)

Nearing, Michelle M.; Koch, Iris; Reimer, Kenneth J.

2014-01-01

The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

The dynamics of arsenic in four paddy fields in the Bengal delta

International Nuclear Information System (INIS)

Stroud, Jacqueline L.; Norton, Gareth J.; Islam, M. Rafiqul; Dasgupta, Tapash; White, Rodger P.; Price, Adam H.; Meharg, Andrew A.; McGrath, Steve P.; Zhao Fangjie

2011-01-01

Irrigation with arsenic contaminated groundwater in the Bengal Delta may lead to As accumulation in the soil and rice grain. The dynamics of As concentration and speciation in paddy fields during dry season (boro) rice cultivation were investigated at 4 sites in Bangladesh and West Bengal, India. Three sites which were irrigated with high As groundwater had elevated As concentrations in the soils, showing a significant gradient from the irrigation inlet across the field. Arsenic concentration and speciation in soil pore water varied temporally and spatially; higher As concentrations were associated with an increasing percentage of arsenite, indicating a reductive mobilization. Concentrations of As in rice grain varied by 2-7 fold within individual fields and were poorly related with the soil As concentration. A field site employing alternating flooded-dry irrigation produced the lowest range of grain As concentration, suggesting a lower soil As availability caused by periodic aerobic conditions. - Research highlights: → Irrigation with As-contaminated groundwater resulted in a gradient of As concentration in the soil. → Arsenic concentration in paddy standing water decreased as arsenite was oxidised to arsenate. → Soil pore water As increased with the %arsenite, suggesting reductive mobilisation. → Alternative flooded-dry conditions led to lowest range of As concentration in rice grain. - Spatial variations of arsenic concentrations in paddy soil and waters do not correlate to within-field variations of arsenic concentrations in rice grain.

Arsenic compounds in a marine food chain

Energy Technology Data Exchange (ETDEWEB)

Goessler, W.; Irgolic, K.J.; Kuehnelt, D.; Schlagenhaufen, C. [Institute for Analytical Chemistry, Karl-Franzens-Universitaet Graz, Universitaetsplatz 1, A-8010 Graz (Austria); Maher, W. [CRC for Freshwater Ecology, University of Canberra, PO Box 1, Belconnen ACT. 2616 (Australia); Kaise, T. [Laboratory of Environmental Chemistry, School of Life Science, University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachijoji, Tokyo 192-03 (Japan)

1997-10-01

A three-organism food chain within a rock pool at Rosedale, NSW, Australia, was investigated with respect to arsenic compounds by high performance liquid chromatography - hydraulic high pressure nebulization - inductively coupled plasma mass spectrometry (HPLC-HHPN-ICP-MS). Total arsenic concentration was determined in the seaweed Hormosira banksii (27.2 {mu}g/g dry mass), in the gastropod Austrocochlea constricta (74.4 {mu}g/g dry mass), which consumes the seaweed, and in the gastropod Morula marginalba (233 {mu}g/g dry mass), which eats Austrocochlea constricta. The major arsenic compounds in the seaweed were (2`R)-dimethyl[1-O-(2`,3`-dihydroxypropyl)-5-deoxy-{beta}-d-ribofuranos-5-yl]arsine oxide and an unidentified compound. The herbivorous gastropod Austrocochlea constricta transformed most of the arsenic taken up with the seaweed to arsenobetaine. Traces of arsenite, arsenate, dimethylarsinic acid, arsenocholine, the tetramethylarsonium cation, and several unknown arsenic compounds were detected. Arsenobetaine accounted for 95% of the arsenic in the carnivorous gastropod Morula marginalba. In Morula marginalba the concentration of arsenocholine was higher, and the concentrations of the minor arsenic compounds lower than in the herbivorous gastropod Austrocochlea constricta. (orig.) With 4 figs., 1 tab., 13 refs.

New Sorbents for Removing Arsenic From Water

Science.gov (United States)

McConchie, D. M.; Genc-Fuhrman, H.; Clark, M. W.; Caldicott, W.; Davies-McConchie, F. G.

2004-12-01

Elevated concentrations of arsenic in the drinking water used in many countries, including some of the poorest developing countries, and recognition that consuming this water can have serious consequences for human health, have led to increased investigations of ways to obtain safe water supplies. Finding new groundwater resources is a possible solution but this is a costly strategy that has no guarantee of success, particularly in areas where water is already a scarce commodity. The alternative is to treat water that is already available, but existing technologies are usually too expensive, too difficult to operate and maintain, or not completely effective when used in less developed countries or remote areas. There is therefore, an urgent need to find a simple and effective but inexpensive sorbent for arsenic that can be used to treat large volumes of water under less than ideal conditions. In this paper we present the results of field and laboratory trials that used a new, highly cost-effective, sorbent to remove arsenic from contaminated water. BauxsolT is the name given to the cocktail of minerals prepared by treating caustic bauxite refinery residues with Mg and Ca to produce a substance with a reaction pH of about 8.5, a high acid neutralizing capacity and an excellent ability to trap trace metals, metalloids and some other ionic species. The trapped ions are tightly bound by processes that include; precipitation of low solubility neoformational minerals, isomorphous substitution, solid-state diffusion, and adsorption; it is also an excellent flocculant. Although ordinary BauxsolT has an excellent ability to bind arsenate, and to a lesser extent arsenite, this ability can be further increased for particular water types by using activated BauxsolT or BauxsolT combined with small amounts of other reagents. Field trials conducted at the Gilt Edge Mine, South Dakota, showed that the addition of BauxsolT to highly sulfidic waste rock reduced the arsenic

A review on environmental factors regulating arsenic methylation in humans

International Nuclear Information System (INIS)

Tseng, C.-H.

2009-01-01

Subjects exposed to arsenic show significant inter-individual variation in urinary patterns of arsenic metabolites but insignificant day-to-day intra-individual variation. The inter-individual variation in arsenic methylation can be partly responsible for the variation in susceptibility to arsenic toxicity. Wide inter-ethnic variation and family correlation in urinary arsenic profile suggest a genetic effect on arsenic metabolism. In this paper the environmental factors affecting arsenic metabolism are reviewed. Methylation capacity might reduce with increasing dosage of arsenic exposure. Furthermore, women, especially at pregnancy, have better methylation capacity than their men counterparts, probably due to the effect of estrogen. Children might have better methylation capacity than adults and age shows inconsistent relevance in adults. Smoking and alcohol consumption might be associated with a poorer methylation capacity. Nutritional status is important in the methylation capacity and folate may facilitate the methylation and excretion of arsenic. Besides, general health conditions and medications might influence the arsenic methylation capacity; and technical problems can cause biased estimates. The consumption of seafood, seaweed, rice and other food with high arsenic contents and the extent of cooking and arsenic-containing water used in food preparation may also interfere with the presentation of the urinary arsenic profile. Future studies are necessary to clarify the effects of the various arsenic metabolites including the trivalent methylated forms on the development of arsenic-induced human diseases with the consideration of the effects of confounding factors and the interactions with other effect modifiers

Determination of leachable arsenic from glass ampoules

International Nuclear Information System (INIS)

Kayasth, S.R.; Swain, K.K.

2004-01-01

Appreciable amounts of different arsenic compounds are used in the manufacture of glass and glass ampoules (injection vials and bottles) used to store drugs. Exposure/intake of arsenic to human beings may result in skin ulceration, injury to mucous membranes, perforation of nasal septum, skin cancer and keratoses, especially of the palms and soles and may cause detrimental effects. Considering the toxicity of arsenic, even if traces of arsenic from such glass containers/ampoules are leached out, it can impart damage to human beings. To check the possibility of leaching of arsenic from glass ampoules, a simple methodology has been developed. Different makes and varieties of glass ampoules filled with de-ionized water were subjected to high pressure and temperature leaching for varying amount of time using autoclave to create extreme conditions for the maximum leaching out of the analyte. Subsequently, the determination of the arsenic contents in leached water using neutron activation analysis is reported in detail with observations. (author)

Isolation of Arsenic Resistant Escherichia coli from Sewage Water and Its Potential in Arsenic Biotransformation

Directory of Open Access Journals (Sweden)

Basanta Bista

2017-04-01

Full Text Available Arsenic contamination in drinking water from ground water poses a threat to the health of a large population in developing countries in Asia. This has sparked great interests in the potential of different microbes in arsenic resistance and removal from water. This study involves isolation of arsenic resistant Escherichia coli from sewage water from Kathmandu University and investigation of its attributes. Arsenic resistant E. coli was successfully isolated which could survive in high concentration of arsenic. The maximum tolerance of arsenite was 909.79 mg/L (sodium arsenite and 3120.1 mg/L arsenate (sodium arsenate which is well above most natural concentration of arsenic in ground water. This particular E. coli tolerated multiple heavy metal like silver nitrate, cobalt sulphate, cadmium chloride, nickel chloride, mercury chloride, copper sulphate, and zinc chloride at concentration 20 µM, 1 mM, 0.5mM, 1mM, 0.01 mM, 1 mM, and 1 mM respectively which are concentrations known to be toxic to E. coli. Biotransformation of arsenite to arsenate was also checked for by a qualitative silver nitrate technique. This E. coli was able to transform arsenate to arsenite. It showed some sensitivity to Ciprofloxacin, Gentamicin and Nalidixic Acid. As E. coli and its genome are very widely studied, these particular properties have a lot of potential in microbial remediation or microbial recovery of metals and possible recombination approaches.

Development of suitable hydroponics system for phytoremediation of arsenic-contaminated water using an arsenic hyperaccumulator plant Pteris vittata.

Science.gov (United States)

Huang, Yi; Miyauchi, Keisuke; Inoue, Chihiro; Endo, Ginro

2016-01-01

In this study, we found that high-performance hydroponics of arsenic hyperaccumulator fern Pteris vittata is possible without any mechanical aeration system, if rhizomes of the ferns are kept over the water surface level. It was also found that very low-nutrition condition is better for root elongation of P. vittata that is an important factor of the arsenic removal from contaminated water. By the non-aeration and low-nutrition hydroponics for four months, roots of P. vittata were elongated more than 500 mm. The results of arsenate phytofiltration experiments showed that arsenic concentrations in water declined from the initial concentrations (50 μg/L, 500 μg/L, and 1000 μg/L) to lower than the detection limit (0.1 μg/L) and about 80% of arsenic removed was accumulated in the fern fronds. The improved hydroponics method for P. vittata developed in this study enables low-cost phytoremediation of arsenic-contaminated water and high-affinity removal of arsenic from water.

Bacteria, hypertolerant to arsenic in the rocks of an ancient gold mine, and their potential role in dissemination of arsenic pollution.

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Drewniak, Lukasz; Styczek, Aleksandra; Majder-Lopatka, Malgorzata; Sklodowska, Aleksandra

2008-12-01

The aim of the present study was to find out if bacteria present in ancient gold mine could transform immobilized arsenic into its mobile form and increase its dissemination in the environment. Twenty-two arsenic-hypertolerant cultivable bacterial strains were isolated. No chemolithoautotrophs, which could use arsenite as an electron donor as well as arsenate as an electron acceptor, were identified. Five isolates exhibited hypertolerance to arsenic: up to 500mM of arsenate. A correlation between the presence of siderophores and high resistance to arsenic was found. The results of this study show that detoxification processes based on arsenate reductase activity might be significant in dissemination of arsenic pollution. It was concluded that the activity of the described heterotrophic bacteria contributes to the mobilization of arsenic in the more toxic As(III) form and a new mechanism of arsenic mobilization from a scorodite was proposed.

Stable isotopes

International Nuclear Information System (INIS)

Evans, D.K.

1986-01-01

Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

Arsenic in North Carolina: public health implications.

Science.gov (United States)

Sanders, Alison P; Messier, Kyle P; Shehee, Mina; Rudo, Kenneth; Serre, Marc L; Fry, Rebecca C

2012-01-01

Arsenic is a known human carcinogen and relevant environmental contaminant in drinking water systems. We set out to comprehensively examine statewide arsenic trends and identify areas of public health concern. Specifically, arsenic trends in North Carolina private wells were evaluated over an eleven-year period using the North Carolina Department of Health and Human Services database for private domestic well waters. We geocoded over 63,000 domestic well measurements by applying a novel geocoding algorithm and error validation scheme. Arsenic measurements and geographical coordinates for database entries were mapped using Geographic Information System techniques. Furthermore, we employed a Bayesian Maximum Entropy (BME) geostatistical framework, which accounts for geocoding error to better estimate arsenic values across the state and identify trends for unmonitored locations. Of the approximately 63,000 monitored wells, 7712 showed detectable arsenic concentrations that ranged between 1 and 806μg/L. Additionally, 1436 well samples exceeded the EPA drinking water standard. We reveal counties of concern and demonstrate a historical pattern of elevated arsenic in some counties, particularly those located along the Carolina terrane (Carolina slate belt). We analyzed these data in the context of populations using private well water and identify counties for targeted monitoring, such as Stanly and Union Counties. By spatiotemporally mapping these data, our BME estimate revealed arsenic trends at unmonitored locations within counties and better predicted well concentrations when compared to the classical kriging method. This study reveals relevant information on the location of arsenic-contaminated private domestic wells in North Carolina and indicates potential areas at increased risk for adverse health outcomes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Arsenic species in ecosystems affected by arsenic-rich spring water near an abandoned mine in Korea

Energy Technology Data Exchange (ETDEWEB)

Kim, Y.T. [Department of Earth System Science, Yonsei University, 134 Shinchon-Dong, Sudaemoon-Gu, Seoul 120-749 (Korea, Republic of); Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Yoon, H.O., E-mail: dunee@kbsi.re.k [Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Yoon, C. [Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Woo, N.C., E-mail: ncwoo@yonsei.ac.k [Department of Earth System Science, Yonsei University, 134 Shinchon-Dong, Sudaemoon-Gu, Seoul 120-749 (Korea, Republic of)

2009-12-15

The objectives of this study were to quantitatively estimate the distribution of arsenic with its speciation and to identify potential pathways for transformation of arsenic species from samples of water, sediments, and plants in the ecosystem affected by the Cheongog Spring, where As(V) concentration reached levels up to 0.270 mg L{sup -1}. After flowing about 100 m downstream, the arsenic level showed a marked reduction to 0.044 mg L{sup -1} (about 84% removal) without noticeable changes in major water chemistry. The field study and laboratory hydroponic experiments with the dominant emergent plants along the creek (water dropwort and thunbergian smartweed) indicated that arsenic distribution, reduction, and speciation appear to be controlled by, (i) sorption onto stream sediments in exchangeable fractions, (ii) bioaccumulation by and possible release from emergent plants, and (iii) transformation of As(V) to As(III) and organic species through biological activities. - Biogeochemical reactions with emergent plants and sediments control the fate of arsenic along creeks originating from a high-As Spring.

Arsenic Pollution Study at Nitra-Krška Ny Location as an Example of Line Contamination

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Varga Michal

2016-05-01

Full Text Available The aim of this article was to identify the level of arsenic in soils and water as a type of line contamination with widespread environmental impact. For this purpose, as the “model locality” was chosen the Nitra River (Krškany location situated around 80 km from the original source of contamination - Zemianske Kostoľany. EcaFlow 150 analyzer was used to identify the content of arsenic in water and soil samples, SEM and EDS were used to characterize morphology, surface area, and chemical composition of primary substrate. In Nitra-Krškany, significant values of arsenic concentrations were observed for surface water, 14.75 μg l-1, which exceeded the WHO international A limit 1.5 times, for filtered water from the sediment, 149.9 μg l-1, with the present exceedance in all categories (WHO international A limit 15 times, and for soil samples, 26.6 mg kg-1, which exceeded 2.6 times the Slovak soil legal limit (10 mg kg-1. Detection of arsenic confirmed line contamination in Nitra - Krškany. As the main source responsible for contamination there was evaluated coal combustion residuals that consist of spherical aggregates from 2 μm to 1 mm dimension, non-linear topography. This type of contamination has a long-term impact due to hazardous materials and non-stable reactive surface area.

Effect of edta on arsenic phytoextraction by arundo donax

International Nuclear Information System (INIS)

Mirza, N.; Pervez, A.; Mahmood, Q.; Shah, M.M.; Farooq, U.

2014-01-01

Ligand assisted metal uptake by plants is recent trend in environmental clean-up. Arundo donax L. has been demonstrated as a suitable bioresource for the phytoextraction of arsenic recently. A. donax L. plants were grown in arsenic contaminated soil with doses (5 and 10 mg kg/sup -1/) of Ethylene Diamine Tetra Acetic Acid (EDTA) to investigate chelator-assisted phytoextraction. The arsenic treatments included control (no metal) and five doses of arsenic, i.e., 50, 100, 300, 600 and 1000 micro g kg/sup -1/ . The arsenic concentrations linearly increased in parts of plant with the increasing arsenic and EDTA in growth medium. Ligand addition also resulted in the increased arsenic accumulation in the shoot over its control plants. EDTA additionat the rate 5 mg kg/sup -1/ to the treatment system may effectively increase the arsenic uptake by A. donax without severe growth suppression. (author)

[Mixture Leaching Remediation Technology of Arsenic Contaminated Soil].

Science.gov (United States)

Chen, Xun-feng; Li, Xiao-ming; Chen, Can; Yang, Qi; Deng, Lin-jing; Xie, Wei-qiang; Zhong, Yui; Huang, Bin; Yang, Wei-qiang; Zhang, Zhi-bei

2016-03-15

Soil contamination of arsenic pollution has become a severely environmental issue, while soil leaching is an efficient method for remediation of arsenic-contaminated soil. In this study, batch tests were primarily conducted to select optimal mixture leaching combination. Firstly, five conventional reagents were selected and combined with each other. Secondly, the fractions were analyzed before and after the tests. Finally, to explore the feasibility of mixed leaching, three soils with different arsenic pollution levels were used to compare the leaching effect. Comparing with one-step washing, the two-step sequential washing with different reagents increased the arsenic removal efficiency. These results showed that the mixture of 4 h 0.5 mol · L⁻¹ NaOH + 4 h 0.1 mol · L⁻¹ EDTA was found to be practicable, which could enhance the removal rate of arsenic from 66.67% to 91.83%, and the concentration of arsenic in soil was decreased from 186 mg · kg⁻¹ to 15.2 mg · kg⁻¹. Furthermore, the results indicated that the distribution of fractions of arsenic in soil changed apparently after mixture leaching. Leaching process could significantly reduce the available contents of arsenic in soil. Moreover, the mixture of 0.5 mol · L⁻¹ NaOH + 0.1 mol L⁻¹ EDTA could well decrease the arsenic concentration in aluminum-type soils, while the mixture of 0.5 mol · L⁻¹ OX + 0.5 mol · L⁻¹ NaOH could well decrease the arsenic concentration in iron-type soils.

Arsenic speciation in arsenic-rich Brazilian soils from gold mining sites under anaerobic incubation

Science.gov (United States)

De Mello, J. W. V.; Talbott, J.L.; Scott, J.; Roy, W.R.; Stucki, J.W.

2007-01-01

Background. Arsenic speciation in environmental samples is essential for studying toxicity, mobility and bio-transformation of As in aquatic and terrestrial environments. Although the inorganic species As(III) and As(V) have been considered dominant in soils and sediments, organisms are able to metabolize inorganic forms of arsenic into organo-arsenic compounds. Arsenosugars and methylated As compounds can be found in terrestrial organisms, but they generally occur only as minor constituents. We investigated the dynamics of arsenic species under anaerobic conditions in soils surrounding gold mining areas from Minas Gerais State, Brazil to elucidate the arsenic biogeochemical cycle and water contamination mechanisms. Methods. Surface soil samples were collected at those sites, namely Paracatu Formation, Banded Iron Formation and Riacho dos Machados Sequence, and incubated in CaCl2 2.5 mmol L-1 suspensions under anaerobic conditions for 1, 28, 56 and 112 days. After that, suspensions were centrifuged and supernatants analyzed for soluble As species by IC-ICPMS and HPLC-ICPMS. Results. Easily exchangeable As was mainly arsenite, except when reducible manganese was present. Arsenate was mainly responsible for the increase in soluble arsenic due to the reductive dissolution of either iron or manganese in samples from the Paracatu Formation and Riacho dos Machados Sequence. On the other hand, organic species of As dominated in samples from the Banded Iron Formation during anaerobic incubation. Discussion. Results are contrary to the expectation that, in anaerobic environments, As release due to the reductive dissolution of Fe is followed by As(V) reduction to As(III). The occurrence of organo-arsenic species was also found to be significant to the dynamics of soluble arsenic, mainly in soils from the Banded Iron Formation (BIF), under our experimental conditions. Conclusions. In general, As(V) and organic As were the dominant species in solution, which is surprising

The stability of arsenic and selenium compounds that were retained in limestone in a coal gasification atmosphere

Energy Technology Data Exchange (ETDEWEB)

Diaz-Somoano, M.; Lopez-Anton, M.A.; Huggins, F.E.; Martinez-Tarazona, M.R. [CSIC, Oviedo (Spain)

2010-01-15

The aim of this work was to evaluate the stability of arsenic and selenium species retained in a lime/limestone mixture obtained by using limestone as a sorbent for gas cleaning in a coal gasification atmosphere. It was found that the stability of arsenic and selenium species produced by the gas-solid reactions with lime/limestone may be affected by their exposure to air and by their contact with water. The results confirm the conclusions of a previous work in which Ca(AsO{sub 2}){sub 2} and CaSe was postulated as the products of the reaction between the arsenic and selenium species present in a coal gasification atmosphere with lime/limestone. Moreover it was proved that the compounds (Ca(AsO{sub 2}){sub 2} and CaSe) may undergo transformations when the sorbents post-retention are stored or disposed of in air. From the results obtained by XAFS it was possible to identify the Ca{sub 3}(AsO{sub 4}){sub 2} produced by the oxidation of the Ca(ASO{sub 2}){sub 2} on the sorbent surface. The XAFS results for selenium showed that the CaSe formed on the sorbent was transformed to form several species, but mainly elemental Se. These changes in the speciation of arsenic and selenium may explain the behavior of the sorbent post-retention during the water solubility test. Although the selenium compounds and the products that may originate from their decomposition in water are not toxic, in the case of arsenic, species like Ca(AsO{sub 2}){sub 2} and Ca{sub 3}(AsO{sub 4}){sub 2} may lixiviate, and generate toxic arsenic compounds in solution that could pose a risk when the sorbent is finally disposed of.

DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMASIII AND DMASIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC

Science.gov (United States)

DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMAsIII and DMAsIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC. L. M. Del Razo1, M. Styblo2, W. R. Cullen3, and D.J. Thomas4. 1Toxicology Section, Cinvestav-IPN, Mexico, D.F., 2Univ. North Carolina, Chapel Hill, NC; 3Uni...

Effect of applying an arsenic-resistant and plant growth-promoting rhizobacterium to enhance soil arsenic phytoremediation by Populus deltoides LH05-17.

Science.gov (United States)

Wang, Q; Xiong, D; Zhao, P; Yu, X; Tu, B; Wang, G

2011-11-01

Bioremediation of highly arsenic (As)-contaminated soil is difficult because As is very toxic for plants and micro-organisms. The aim of this study was to investigate soil arsenic removal effects using poplar in combination with the inoculation of a plant growth-promoting rhizobacterium (PGPR). A rhizobacterium D14 was isolated and identified within Agrobacterium radiobacter. This strain was highly resistant to arsenic and produced indole acetic acid and siderophore. Greenhouse pot bioremediation experiments were performed for 5 months using poplar (Populus deltoides LH05-17) grown on As-amended soils, inoculated with strain D14. The results showed that P. deltoides was an efficient arsenic accumulator; however, high As concentrations (150 and 300 mg kg(-1)) inhibited its growth. With the bacterial inoculation, in the 300 mg kg(-1) As-amended soils, 54% As in the soil was removed, which was higher than the uninoculated treatments (43%), and As concentrations in roots, stems and leaves were significantly increased by 229, 113 and 291%, respectively. In addition, the As translocation ratio [(stems + leaves)/roots = 0·8] was significantly higher than the uninoculated treatments (0·5). About 45% As was translocated from roots to the above-ground tissues. The plant height and dry weight of roots, stems and leaves were all enhanced; the contents of chlorophyll and soluble sugar, and the activities of superoxide dismutase and catalase were all increased; and the content of a toxic compound malondialdehyde was decreased. The results indicated that the inoculation of strain D14 could contribute to the increase in the As tolerance of P. deltoides, promotion of the growth, increase in the uptake efficiency and enhancement of As translocation. The use of P. deltoides in combination with the inoculation of strain D14 provides a potential application for efficient soil arsenic bioremediation. © 2011 The Authors. Journal of Applied Microbiology ©2011 The Society for Applied

Arsenic efflux from Microcystis aeruginosa under different phosphate regimes.

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Changzhou Yan

Full Text Available Phytoplankton plays an important role in arsenic speciation, distribution, and cycling in freshwater environments. Little information, however, is available on arsenic efflux from the cyanobacteria Microcystis aeruginosa under different phosphate regimes. This study investigated M. aeruginosa arsenic efflux and speciation by pre-exposing it to 10 µM arsenate or arsenite for 24 h during limited (12 h and extended (13 d depuration periods under phosphate enriched (+P and phosphate depleted (-P treatments. Arsenate was the predominant species detected in algal cells throughout the depuration period while arsenite only accounted for no greater than 45% of intracellular arsenic. During the limited depuration period, arsenic efflux occurred rapidly and only arsenate was detected in solutions. During the extended depuration period, however, arsenate and dimethylarsinic acid (DMA were found to be the two predominant arsenic species detected in solutions under -P treatments, but arsenate was the only species detected under +P treatments. Experimental results also suggest that phosphorus has a significant effect in accelerating arsenic efflux and promoting arsenite bio-oxidation in M. aeruginosa. Furthermore, phosphorus depletion can reduce arsenic efflux from algal cells as well as accelerate arsenic reduction and methylation. These findings can contribute to our understanding of arsenic biogeochemistry in aquatic environments and its potential environmental risks under different phosphorus levels.

Magentite nanoparticle for arsenic remotion

International Nuclear Information System (INIS)

Viltres, H; Reguera, E; Odio, O F; Borja, R; Aguilera, Y

2017-01-01

Inorganic As (V) and As (III) species are commonly found in groundwater in many countries around the world. It is known that arsenic is highly toxic and carcinogenic, at present exist reports of diverse countries with arsenic concentrations in drinking water higher than those proposed by the World Health Organization (10 μg/L). It has been reported that adsorption strategies using magnetic nanoparticles as magnetite (<20 nm) proved to be very efficient for the removal of arsenic in drinking water. Magnetic nanoparticles (magnetite) were prepared using a co-precipitation method with FeCl 3 and FeCl 2 as metal source and NaOH aqueous solution as precipitating agent. Magnetite nanoparticles synthesized were put in contact with As 2 O 3 and As 2 O 5 solutions at room temperature to pH 4 and 7. The nanoparticles were characterized by FT-IR, DRX, UV-vis, and XRF. The results showed that synthesized magnetite had an average diameter of 11 nm and a narrow size distribution. The presence of arsenic on magnetite nanoparticles surface was confirmed, which is more remarkable when As (V) is employed. Besides, it is possible to observe that no significant changes in the band gap values after adsorption of arsenic in the nanoparticles. (paper)

Rhizosphere colonization and arsenic translocation in sunflower (Helianthus annuus L.) by arsenate reducing Alcaligenes sp. strain Dhal-L.

Science.gov (United States)

Cavalca, Lucia; Corsini, Anna; Bachate, Sachin Prabhakar; Andreoni, Vincenza

2013-10-01

In the present study, six arsenic-resistant strains previously isolated were tested for their plant growth promoting characteristics and heavy metal resistance, in order to choose one model strain as an inoculum for sunflower plants in pot experiments. The aim was to investigate the effect of arsenic-resistant strain on sunflower growth and on arsenic uptake from arsenic contaminated soil. Based on plant growth promoting characteristics and heavy metal resistance, Alcaligenes sp. strain Dhal-L was chosen as an inoculum. Beside the ability to reduce arsenate to arsenite via an Ars operon, the strain exhibited 1-amino-cyclopropane-1-carboxylic acid deaminase activity and it was also able to produce siderophore and indole acetic acid. Pot experiments were conducted with an agricultural soil contaminated with arsenic (214 mg kg⁻¹). A real time PCR method was set up based on the quantification of ACR3(2) type of arsenite efflux pump carried by Alcaligenes sp. strain Dhal-L, in order to monitor presence and colonisation of the strain in the bulk and rhizospheric soil. As a result of strain inoculation, arsenic uptake by plants was increased by 53 %, whereas ACR3(2) gene copy number in rhizospheric soil was 100 times higher in inoculated than in control pots, indicating the colonisation of strain. The results indicated that the presence of arsenate reducing strains in the rhizosphere of sunflower influences arsenic mobilization and promotes arsenic uptake by plant.

Sedimentology and arsenic pollution in the Bengal Basin: insight into arsenic occurrence and subsurface geology.

Science.gov (United States)

Hills, Andrew; McArthur, John

2014-05-01

The Bengal delta system is a geologically recent feature overlying a deeply incised palaeo-surface formed during the Last Glacial Maximum. This surface is a series of terraces and valleys created by river incision (Goodbred & Kuehl 2003). The terraces were weathered, forming a thin, indurated laterite deposit (Goodbred & Kuehl 2000) at depths greater than 50 m. McArthur et al. (2008) define this as a palaeosol and have identified it at depths greater than 30 m though out Bangladesh and West Bengal. It has been observed that arsenic concentrations at these sites are lower than the rest of the delta. It has been assumed that the surface morphology at sites where there is a palaeosol are similar and can therefore be characterised by remote sensing, in the form of Google Earth images. Sites were selected in Bangladesh and West Bengal, from work by McArthur et al. (2011); Hoque et al. (2012), where groundwater chemistry and sedimentology data are available making it possible to determine if the subsurface is a palaeo-channel or palaeo-interfluve. Arsenic concentration data have been inputted into Google Earth and the palaeo-channels marked where the arsenic concentration is greater than 10 µg/L, and palaeo-interfluves where arsenic concentration is less than 10 µg/L. The surface morphologies in these domains have been examined for similarities, and it was shown that avulsion scars and abandoned river channels are found where arsenic concentrations are greater than 10 µg/L. Conversely the surrounding areas that are devoid of channel scars have arsenic concentrations less than 10 µg/L. Using the correlation between avulsion features being representative of palaeo-channels and high arsenic concentrations, sites were selected that had a similar surface morphology to the type localities. A comparison of these images and arsenic concentrations showed that the postulate is valid for over 80 percent of cases. Where this is not valid, this could indicate that the subsurface

Arsenic in Ground Water of the United States

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... Team More Information Arsenic in groundwater of the United States Arsenic in groundwater is largely the result of ... Gronberg (2011) for updated arsenic map. Featured publications United States Effects of human-induced alteration of groundwater flow ...

[Arsenic - Poison or medicine?].

Science.gov (United States)

Kulik-Kupka, Karolina; Koszowska, Aneta; Brończyk-Puzoń, Anna; Nowak, Justyna; Gwizdek, Katarzyna; Zubelewicz-Szkodzińska, Barbara

2016-01-01

Arsenic (As) is commonly known as a poison. Only a few people know that As has also been widely used in medicine. In the past years As and its compounds were used as a medicine for the treatment of such diseases as diabetes, psoriasis, syphilis, skin ulcers and joint diseases. Nowadays As is also used especially in the treatment of patients with acute promyelocytic leukemia. The International Agency for Research on Cancer (IARC) has recognized arsenic as an element with carcinogenic effect evidenced by epidemiological studies, but as previously mentioned it is also used in the treatment of neoplastic diseases. This underlines the specificity of the arsenic effects. Arsenic occurs widely in the natural environment, for example, it is present in soil and water, which contributes to its migration to food products. Long exposure to this element may lead to liver damages and also to changes in myocardium. Bearing in mind that such serious health problems can occur, monitoring of the As presence in the environmental media plays a very important role. In addition, the occupational risk of As exposure in the workplace should be identified and checked. Also the standards for As presence in food should be established. This paper presents a review of the 2015 publications based on the Medical database like PubMed and Polish Medical Bibliography. It includes the most important information about arsenic in both forms, poison and medicine. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Arsenic metabolites in humans after ingestion of wakame seaweed

Directory of Open Access Journals (Sweden)

Hata A.

2013-04-01

Full Text Available Seaweed contains large amounts of various arsenic compounds such as arsenosugars (AsSugs, but their relative toxicities have not yet been fully evaluated. A risk evaluation of dietary arsenic would be necessary. After developing an arsenic speciation analysis of wakame seaweed (Undaria pinnatifida, we conducted a wakame ingestion experiment using volunteers. Five volunteers ingested 300 g of commercial wakame after refraining from seafood for 5 days. Arsenic metabolites in the urine were monitored over a 5-day period after ingestion. Total arsenic concentration of the wakame seaweed was 34.3 ± 2.1 mg arsenic/kg (dry weight, n = 3. Two AsSugs, 3-[5′-deoxy-5′-(dimethyl-arsinoyl-β-ribofuranosyloxy]-propylene glycol (AsSug328 and 3-[5′-deoxy-5′-(dimethyl-arsinoyl-β- ribofuranosyl-oxy]-2-hydroxypropyl-2,3-dihydroxy-propyl phosphate (AsSug482 were detected, but arsenobetaine, dimethylarsinic acid (DMA, monomethylarsonic acid, and inorganic arsenics (iAs were not detected. The major peak was AsSug328, which comprised 89% of the total arsenic. Approximately 30% of the total arsenic ingested was excreted in the urine during the 5-day observation. Five arsenic compounds were detected in the urine after ingestion, the major one being DMA, which comprised 58.1 ± 5.0% of the total urinary arsenic excreted over the 5 days. DMA was believed to be metabolized not from iAs but from AsSugs, and its biological half-time was approximately 13 h.

Catecholate-siderophore produced by As-resistant bacterium effectively dissolved FeAsO_4 and promoted Pteris vittata growth

International Nuclear Information System (INIS)

Liu, Xue; Yang, Guang-Mei; Guan, Dong-Xing; Ghosh, Piyasa; Ma, Lena Q.

2015-01-01

The impact of siderophore produced by arsenic-resistant bacterium Pseudomonas PG12 on FeAsO_4 dissolution and plant growth were examined. Arsenic-hyperaccumulator Pteris vittata was grown for 7 d in 0.2-strength Fe-free Hoagland solution containing FeAsO_4 mineral and PG12-siderophore or fungal-siderophore desferrioxamine B (DFOB). Standard siderophore assays indicated that PG12-siderophore was catecholate-type. PG12-siderophore was more effective in promoting FeAsO_4 dissolution, and Fe and As plant uptake than DFOB. Media soluble Fe and As in PG12 treatment were 34.6 and 3.07 μM, 1.6- and 1.4-fold of that in DFOB. Plant Fe content increased from 2.93 to 6.24 g kg"−"1 in the roots and As content increased from 14.3 to 78.5 mg kg"−"1 in the fronds. Besides, P. vittata in PG12 treatment showed 2.6-times greater biomass than DFOB. While P. vittata fronds in PG12 treatment were dominated by AsIII, those in DFOB treatment were dominated by AsV (61–77%). This study showed that siderophore-producing arsenic-resistant rhizobacteria may have potential in enhancing phytoremediation of arsenic-contaminated soils. - Graphical abstract: As-induced root exudate phytate enhanced FeAsO_4 dissolution, and As uptake and plant growth of Pteris vittata. Display Omitted - Highlights: • Arsenic-resistant rhizobacterium Pseudomonas PG12 was from rhizosphere of As-hyperaccumulator Pteris vittata. • PG12 was effective in producing catecholate-type siderophore with high affinity with Fe. • PG12-produced siderophore increased Fe and As uptake and growth in P. vittata. - Siderophores produced by arsenic-resistant bacteria were effective in solubilizing FeAsO_4 mineral and enhancing plant growth of As-hyperaccumulator Pteris vittata.

Regenerating an Arsenic Removal Iron-Based Adsorptive ...

Science.gov (United States)

The replacement of exhausted, adsorptive media used to remove arsenic from drinking water accounts for approximately 80% of the total operational and maintenance (O/M) costs of this commonly used small system technology. The results of three, full scale system studies of an on-site media regeneration process (Part 1) showed it to be effective in stripping arsenic and other contaminants from the exhausted media. Part 2, of this two part paper, presents information on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement. The results of the studies indicate that regenerated media is very effective in removing arsenic and the regeneration cost is substantially less than the media replacement cost. On site regeneration, therefore, provides small systems with alternative to media replacement when removing arsenic from drinking water using adsorptive media technology. Part 2 of a two part paper on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement.

TREATMENT TECHNOLOGIES FOR ARSENIC REMOVAL

Science.gov (United States)

The United States Environmental Protection Agency (US EPA) recently reduced the arsenic maximum contaminant level (MCL) from 0.050 mg/L to 0.010 mg/L. In order to increase arsenic outreach efforts, a summary of the new rule, related health risks, treatment technologies, and desig...

Effects of Nrf2 deficiency on arsenic metabolism in mice.

Science.gov (United States)

Wang, Huihui; Zhu, Jiayu; Li, Lu; Li, Yongfang; Lv, Hang; Xu, Yuanyuan; Sun, Guifan; Pi, Jingbo

2017-12-15

Inorganic arsenic (iAs) is a known toxicant and carcinogen. Worldwide arsenic exposure has become a threat to human health. The severity of arsenic toxicity is strongly correlated with the speed of arsenic metabolism (methylation) and clearance. Furthermore, oxidative stress is recognized as a major mechanism for arsenic-induced toxicity. Nuclear factor-E2-related factor 2 (Nrf2), a key regulator in cellular adaptive antioxidant response, is clearly involved in alleviation of arsenic-induced oxidative damage. Multiple studies demonstrate that Nrf2 deficiency mice are more vulnerable to arsenic-induced intoxication. However, what effect Nrf2 deficiency might have on arsenic metabolism in mice is still unknown. In the present study, we measured the key enzymes involved in arsenic metabolism in Nrf2-WT and Nrf2-KO mice. Our results showed that basal transcript levels of glutathione S-transferase omega 2 (Gsto2) were significantly higher and GST mu 1 (Gstm1) lower in Nrf2-KO mice compared to Nrf2-WT control. Arsenic speciation and methylation rate in liver and urine was then studied in mice treated with 5mg/kg sodium arsenite for 12h. Although there were some alterations in arsenic metabolism enzymes between Nrf2-WT and Nrf2-KO mice, the Nrf2 deficiency had no significant effect on arsenic methylation. These results suggest that the Nrf2-KO mice are more sensitive to arsenic than Nrf2-WT mainly because of differences in adaptive antioxidant detoxification capacity rather than arsenic methylation capacity. Copyright © 2017. Published by Elsevier Inc.

Legacy of the California Gold Rush: Environmental geochemistry of arsenic in the southern Mother Lode Gold District

Science.gov (United States)

Savage, K.S.; Bird, D.K.; Ashley, R.P.

2000-01-01

Gold mining activity in the Sierra Nevada foothills, both recently and during the California Gold Rush, has exposed arsenic-rich pyritic rocks to weathering and erosion. This study describes arsenic concentration and speciation in three hydrogeologic settings in the southern Mother Lode Gold District: mineralized outcrops and mine waste rock (overburden); mill tailings submerged in a water reservoir; and lake waters in this monomictic reservoir and in a monomictic lake developing within a recent open-pit mine. These environments are characterized by distinct modes of rock-water interaction that influence the local transport and fate of arsenic. Arsenic in outcrops and waste rock occurs in arsenian pyrite containing an average of 2 wt% arsenic. Arsenic is concentrated up to 1300 ppm in fine-grained, friable iron-rich weathering products of the arsenian pyrite (goethite, jarosite, copiapite), which develop as efflorescences and crusts on weathering outcrops. Arsenic is sorbed as a bidentate complex on goethite, and substitutes for sulfate in jarosite. Submerged mill tailings obtained by gravity core at Don Pedro Reservoir contain arsenic up to 300 ppm in coarse sand layers. Overlying surface muds have less arsenic in the solid fraction but higher concentrations in porewaters (up to 500 ??g/L) than the sands. Fine quartz tailings also contain up to 3.5 ppm mercury related to the ore processing. The pH values in sediment porewaters range from 3.7 in buried gypsum-bearing sands and tailings to 7 in the overlying lake sediments. Reservoir waters immediately above the cores contain up to 3.5 ??g/L arsenic; lake waters away from the submerged tailings typically contain less than 1 ??g/L arsenic. Dewatering during excavation of the Harvard open-pit mine produced a hydrologic cone of depression that has been recovering toward the pre-mining groundwater configuration since mining ended in 1994. Aqueous arsenic concentrations in the 80 m deep pit lake are up to 1000 ??g

Establishment of Groundwater Arsenic Potential Distribution and Discrimination in Taiwan

Science.gov (United States)

Tsai, Kuo Sheng; Chen, Yu Ying; Chung Liu, Chih; Lin, Chien Wen

2016-04-01

According to the last 10 years groundwater monitoring data in Taiwan, Arsenic concentration increase rapidly in some areas, similar to Bengal and India, the main source of Arsenic-polluted groundwater is geological sediments, through reducing reactions. There are many researches indicate that high concentration of Arsenic in groundwater poses the risk to water safety, for example, the farm lands irrigation water contains Arsenic cause the concentration of Arsenic increase in soil and crops. Based on the management of water usage instead of remediation in the situation of insufficient water. Taiwan EPA has been developed the procedures of Arsenic contamination potential area establishment and source discriminated process. Taiwan EPA use the procedures to determine the management of using groundwater, and the proposing usage of Arsenic groundwater accordance with different objects. Agencies could cooperate with the water quality standard or water needs, studying appropriate water purification methods and the groundwater depth, water consumption, thus achieve the goal of water safety and environmental protection, as a reference of policy to control total Arsenic concentration in groundwater. Keywords: Arsenic; Distribution; Discrimination; Pollution potential area of Arsenic; Origin evaluation of groundwater Arsenic

The Case for Visual Analytics of Arsenic Concentrations in Foods

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Omotayo R. Awofolu

2010-04-01

Full Text Available Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i metabolism of arsenic in the human body; (ii arsenic concentrations in various foods; (ii factors affecting arsenic uptake in plants; (ii introduction to visual analytics; and (iv benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species.

ARSENIC IN DRINKING WATER SUPPLY WELLS: A MULTI ...

Science.gov (United States)

Studies have indicated that arsenic concentrations greater than the new U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) concentration of 10 micrograms per liter (µg/L) occur in numerous aquifers around the United States. One such aquifer is the Central Oklahoma aquifer, which supplies drinking water to numerous communities in central Oklahoma. Concentrations as high as 230 µg/L have been reported in some drinking water supply wells from this aquifer. The city of Norman, like most other affected cities, is actively seeking a cost-effective solution to the arsenic problem. Only six of the city’s 32 wells exceeded the old MCL of 50 µg/L. With implementation of the new MCL this year, 18 of the 32 wells exceed the allowable concentration of arsenic. Arsenic-bearing shaly sandstones appear to be the source of the arsenic. It may be possible to isolate these arsenic-bearing zones from water supply wells, enabling production of water that complies with drinking water standards. It is hypothesized that geologic mapping together with detailed hydrogeochemical investigations will yield correlations which predict high arsenic occurrence for the siting of new drinking water production wells. More data and methods to assess the specific distribution, speciation, and mode of transport of arsenic in aquifers are needed to improve our predictions for arsenic occurrence in water supply wells. Research is also needed to assess whether we can ret

Environmental Arsenic Exposure and Microbiota in Induced Sputum

Directory of Open Access Journals (Sweden)

Allison G. White

2014-02-01

Full Text Available Arsenic exposure from drinking water is associated with adverse respiratory outcomes, but it is unknown whether arsenic affects pulmonary microbiota. This exploratory study assessed the effect of exposure to arsenic in drinking water on bacterial diversity in the respiratory tract of non-smokers. Induced sputum was collected from 10 subjects with moderate mean household water arsenic concentration (21.1 ± 6.4 ppb and 10 subjects with low household water arsenic (2.4 ± 0.8 ppb. To assess microbiota in sputum, the V6 hypervariable region amplicons of bacterial 16s rRNA genes were sequenced using the Ion Torrent Personal Genome Machine. Microbial community differences between arsenic exposure groups were evaluated using QIIME and Metastats. A total of 3,920,441 sequence reads, ranging from 37,935 to 508,787 per sample for 316 chips after QIIME quality filtering, were taxonomically classified into 142 individual genera and five phyla. Firmicutes (22%, Proteobacteria (17% and Bacteriodetes (12% were the main phyla in all samples, with Neisseriaceae (15%, Prevotellaceae (12% and Veillonellacea (7% being most common at the genus level. Some genera, including Gemella, Lactobacillales, Streptococcus, Neisseria and Pasteurellaceae were elevated in the moderate arsenic exposure group, while Rothia, Prevotella, Prevotellaceae Fusobacterium and Neisseriaceae were decreased, although none of these differences was statistically significant. Future studies with more participants and a greater range of arsenic exposure are needed to further elucidate the effects of drinking water arsenic consumption on respiratory microbiota.

Behavior of arsenic impurity at antimony electric precipitation

International Nuclear Information System (INIS)

Kim, G.N.; Rakhmanov, A.

2001-01-01

In the paper the arsenic impurity electrochemical behavior and it purification from antimony by electric precipitation out of fluoride solutions was studied. For this the arsenic sample with mass 0.003-0.006 g has been irradiated at the WWR-SM nuclear reactor during 3-5 hour in the thermal neutron flux 10 13 n/cm 2 s, after 24 h keeping the sample has being dissolved in the concentrated nitric acid, and then it has been evaporated several times with distillation water addition up to wet precipitation state. It is shown, that arsenic impurity behavior character in the antimony electric precipitation out to fluoride electrolyte depends on the electrolyte content, electrolysis conditions, arsenic valency state in arsenic impurity existence in the five-valency state its joint electric reduction with antimony is practically not observing. In the case the arsenic being in three-valency state, it joint electric reduction with antimony is taking place. In this time the electrolytic antimony contents arsenic impurities less in dozen time than initial material

Assessment of Nutritional Status of Infants Living in Arsenic-Contaminated Areas in Bangladesh and Its Association with Arsenic Exposure

Science.gov (United States)

Milton, Abul Hasnat; Attia, John; Alauddin, Mohammad; McEvoy, Mark; McElduff, Patrick; Hussain, Sumaira; Akhter, Ayesha; Akter, Shahnaz; Islam, M. Munirul; Ahmed, AM Shamsir; Iyengar, Vasu; Islam, Md Rafiqul

2018-01-01

Data is scarce on early life exposure to arsenic and its association with malnutrition during infancy. This study followed the nutritional status of a cohort of 120 infants from birth to 9 months of age in an arsenic contaminated area in Bangladesh. Anthropometric data was collected at 3, 6 and 9 months of the infant’s age for nutritional assessment whereas arsenic exposure level was assessed via tube well drinking water arsenic concentration at the initiation of the study. Weight and height measurements were converted to Z-scores of weight for age (WAZ-underweight), height for age (HAZ-stunting), weight for height (WHZ-wasting) for children by comparing with WHO growth standard. Arsenic exposure levels were categorized as <50 μg/L and ≥50 μg/L. Stunting rates (<−2 SD) were 10% at 3 months and 44% at both 6 and 9 months. Wasting rates (<−2 SD) were 23.3% at 3 months and underweight rates (<−2 SD) were 25% and 10% at 3 and 6 months of age, respectively. There was a significant association of stunting with household drinking water arsenic exposure ≥50 μg/L at age of 9 months (p = 0.009). Except for stunting at 9 months of age, we did not find any significant changes in other nutritional indices over time or with levels of household arsenic exposure in this study. Our study suggests no association between household arsenic exposure and under-nutrition during infancy; with limiting factors being small sample size and short follow-up. Difference in stunting at 9 months by arsenic exposure at ≥50 μg/L might be a statistical incongruity. Further longitudinal studies are warranted to establish any association. PMID:29301293

Urinary total arsenic and 8-hydroxydeoxyguanosine are associated with renal cell carcinoma in an area without obvious arsenic exposure

Energy Technology Data Exchange (ETDEWEB)

Huang, Chao-Yuan [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Chung, Chi-Jung [Department of Health Risk Management, College of Public Health, China Medical University, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Chu, Jan-Show [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Pathology, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Yang, Hsiu-Yuan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Wu, Chia-Chang [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, Taipei Medical Universtiy-Shuang Ho Hospital, Taipei, Taiwan (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China)

2012-08-01

8-Hydroxydeoxyguanosine (8-OHdG) is one of the most reliable and abundant markers of DNA damage. The study was designed to explore the relationship between urinary 8-OHdG and renal cell carcinoma (RCC) and to investigate whether individuals with a high level of 8-OHdG would have a modified odds ratio (OR) of arsenic-related RCC. This case–control study was conducted with 132 RCC patients and 245 age- and sex-matched controls from a hospital-based pool between November 2006 and May 2009. Pathological verification of RCC was completed by image-guided biopsy or surgical resection of renal tumors. Urinary 8-OHdG levels were determined using liquid chromatography with tandem mass spectrometry (LC–MS/MS). Concentrations of urinary arsenic species, including inorganic arsenic, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), were determined by a high performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Level of urinary 8-OHdG was significantly associated with the OR of RCC in a dose–response relationship after multivariate adjustment. Urinary 8-OHdG was significantly related to urinary total arsenic. The greatest OR (3.50) was seen in the individuals with high urinary 8-OHdG and high urinary total arsenic. A trend test indicated that the OR of RCC was increased with one of these factors and was further increased with both (p = 0.002). In conclusion, higher urinary 8-OHdG was a strong predictor of the RCC. High levels of 8-OHdG combined with urinary total arsenic might be indicative of arsenic-induced RCC. -- Highlights: ► Urinary 8-OHdG was significantly related to urinary total arsenic. ► Higher urinary 8-OHdG was a strong predictor of RCC risk. ► Urinary 8-OHdG may modify arsenic related RCC risk.

Arsenic in sediments from the southeastern Baltic Sea

International Nuclear Information System (INIS)

Garnaga, Galina; Wyse, Eric; Azemard, Sabine; Stankevicius, Algirdas; Mora, Stephen de

2006-01-01

Arsenic occurs as a persistent constituent in many of the chemical weapons dumped into the Baltic Sea; it can be used as an indicator of leakage and dispersal of released munitions to the marine environment. Total arsenic was analysed in sediment samples taken from the Lithuanian economic zone in the Baltic Sea, which included samples from the chemical munitions dumpsite in the Gotland Basin and national monitoring stations in the southeastern Baltic Sea. Arsenic concentrations in sediments ranged from 1.1 to 19.0 mg kg -1 , with an average of 3.4 mg kg -1 . Although there was evidence of slightly elevated arsenic content in sediments near the weapons dumpsite, arsenic concentrations were nevertheless quite low relative to other investigations in the Baltic and North Seas. - Arsenic concentrations in sediments near chemical weapons dumpsites were only slightly elevated

Effects of organic matter and ageing on the bioaccessibility of arsenic

International Nuclear Information System (INIS)

Meunier, Louise; Koch, Iris; Reimer, Kenneth J.

2011-01-01

Arsenic-contaminated soils may pose a risk to human health. Redevelopment of contaminated sites may involve amending soils with organic matter, which potentially increases arsenic bioaccessibility. The effects of ageing on arsenic-contaminated soils mixed with peat moss were evaluated in a simulated ageing period representing two years, during which arsenic bioaccessibility was periodically measured. Significant increases (p = 0.032) in bioaccessibility were observed for 15 of 31 samples tested, particularly in comparison with samples originally containing >30% bioaccessible arsenic in soils naturally rich in organic matter (>25%). Samples where percent arsenic bioaccessibility was unchanged with age were generally poor in organic matter (average 7.7%) and contained both arsenopyrite and pentavalent arsenic forms that remained unaffected by the organic matter amendments. Results suggest that the addition of organic matter may lead to increases in arsenic bioaccessibility, which warrants caution in the evaluation of risks associated with redevelopment of arsenic-contaminated land. - Highlights: → Adding organic matter to contaminated soils may increase arsenic bioaccessibility. → Ageing soils with >25% organic matter can lead to increased arsenic bioaccessibility. → No changes in arsenic bioaccessibility for soils poor in organic matter (mean 7.7%). → No changes in arsenic bioaccessibility for samples containing arsenopyrite. → Organic matter in soil may favour oxidation of trivalent arsenic to pentavalent form. - Adding organic carbon may increase arsenic bioaccessibility, especially in samples originally containing >30% bioaccessible arsenic in organic carbon-rich soils (>25%).

XAS Studies of Arsenic in the Environment

International Nuclear Information System (INIS)

Charnock, J. M.; Polya, D. A.; Gault, A. G.; Morgan, A. J.

2007-01-01

Arsenic is present in low concentrations in much of the Earth's crust and changes in its speciation are vital to understanding its transport and toxicity in the environment. We have used X-ray absorption spectroscopy to investigate the coordination sites of arsenic in a wide variety of samples, including soil and earthworm tissues from arsenic-contaminated land, and human hair and nail samples from people exposed to arsenic in Cambodia. Our results confirm the effectiveness of using X-ray absorption near edge structure (XANES) and X-ray absorption fine structure (EXAFS) spectroscopy to determine speciation changes in environmental samples

Analysis of arsenical metabolites in biological samples.

Science.gov (United States)

Hernandez-Zavala, Araceli; Drobna, Zuzana; Styblo, Miroslav; Thomas, David J

2009-11-01

Quantitation of iAs and its methylated metabolites in biological samples provides dosimetric information needed to understand dose-response relations. Here, methods are described for separation of inorganic and mono-, di-, and trimethylated arsenicals by thin layer chromatography. This method has been extensively used to track the metabolism of the radionuclide [(73)As] in a variety of in vitro assay systems. In addition, a hydride generation-cryotrapping-gas chromatography-atomic absorption spectrometric method is described for the quantitation of arsenicals in biological samples. This method uses pH-selective hydride generation to differentiate among arsenicals containing trivalent or pentavalent arsenic.

Arsenic exposure at low-to-moderate levels and skin lesions, arsenic metabolism, neurological functions, and biomarkers for respiratory and cardiovascular diseases: Review of recent findings from the Health Effects of Arsenic Longitudinal Study (HEALS) in Bangladesh

International Nuclear Information System (INIS)

Chen Yu; Parvez, Faruque; Gamble, Mary; Islam, Tariqul; Ahmed, Alauddin; Argos, Maria; Graziano, Joseph H.; Ahsan, Habibul

2009-01-01

The contamination of groundwater by arsenic in Bangladesh is a major public health concern affecting 35-75 million people. Although it is evident that high levels (> 300 μg/L) of arsenic exposure from drinking water are related to adverse health outcomes, health effects of arsenic exposure at low-to-moderate levels (10-300 μg/L) are not well understood. We established the Health Effects of Arsenic Longitudinal Study (HEALS) with more than 20,000 men and women in Araihazar, Bangladesh, to prospectively investigate the health effects of arsenic predominately at low-to-moderate levels (0.1 to 864 μg/L, mean 99 μg/L) of arsenic exposure. Findings to date suggest adverse effects of low-to-moderate levels of arsenic exposure on the risk of pre-malignant skin lesions, high blood pressure, neurological dysfunctions, and all-cause and chronic disease mortality. In addition, the data also indicate that the risk of skin lesion due to arsenic exposure is modifiable by nutritional factors, such as folate and selenium status, lifestyle factors, including cigarette smoking and body mass index, and genetic polymorphisms in genes related to arsenic metabolism. The analyses of biomarkers for respiratory and cardiovascular functions support that there may be adverse effects of arsenic on these outcomes and call for confirmation in large studies. A unique strength of the HEALS is the availability of outcome data collected prospectively and data on detailed individual-level arsenic exposure estimated using water, blood and repeated urine samples. Future prospective analyses of clinical endpoints and related host susceptibility will enhance our knowledge on the health effects of low-to-moderate levels of arsenic exposure, elucidate disease mechanisms, and give directions for prevention.

Arsenate impact on the metabolite profile, production and arsenic loading of xylem sap in cucumbers (Cucumis sativus L.

Directory of Open Access Journals (Sweden)

Kalle eUroic

2012-04-01

Full Text Available Arsenic uptake and translocation studies on xylem sap focus generally on the concentration and speciation of arsenic in the xylem. Arsenic impact on the xylem sap metabolite profile and its production during short term exposure has not been reported in detail. To investigate this, cucumbers were grown hydroponically and arsenate (AsV and DMA were used for plant treatment for 24 h. Total arsenic and arsenic speciation in xylem sap was analysed including a metabolite profiling under arsenate stress. Produced xylem sap was quantified and absolute arsenic transported was determined. AsV exposure has a significant impact on the metabolite profile of xylem sap. Four m/z values corresponding to four compounds were up regulated, one compound down regulated by arsenate exposure. The compound down regulated was identified to be isoleucine. Furthermore, arsenate has a significant influence on sap production, leading to a reduction of up to 96 % sap production when plants are exposed to 1000 μg kg-1 arsenate. No difference to control plants was observed when plants were exposed to 1000 μg kg-1 DMA. Absolute arsenic amount in xylem sap was the lowest at high arsenate exposure. These results show that AsV has a significant impact on the production and metabolite profile of xylem sap. The physiological importance of isoleucine needs further attention.

Arsenate Impact on the Metabolite Profile, Production, and Arsenic Loading of Xylem Sap in Cucumbers (Cucumis sativus L.)

Science.gov (United States)

Uroic, M. Kalle; Salaün, Pascal; Raab, Andrea; Feldmann, Jörg

2012-01-01

Arsenic uptake and translocation studies on xylem sap focus generally on the concentration and speciation of arsenic in the xylem. Arsenic impact on the xylem sap metabolite profile and its production during short term exposure has not been reported in detail. To investigate this, cucumbers were grown hydroponically and arsenate (AsV) and DMA were used for plant treatment for 24 h. Total arsenic and arsenic speciation in xylem sap was analyzed including a metabolite profiling under AsV stress. Produced xylem sap was quantified and absolute arsenic transported was determined. AsV exposure had a significant impact on the metabolite profile of xylem sap. Four m/z values corresponding to four compounds were up-regulated, one compound down-regulated by AsV exposure. The compound down-regulated was identified to be isoleucine. Furthermore, AsV exposure had a significant influence on sap production, leading to a reduction of up to 96% sap production when plants were exposed to 1000 μg kg−1 AsV. No difference to control plants was observed when plants were exposed to 1000 μg kg−1 DMA. Absolute arsenic amount in xylem sap was the lowest at high AsV exposure. These results show that AsV has a significant impact on the production and metabolite profile of xylem sap. The physiological importance of isoleucine needs further attention. PMID:22536187

Stable groundwater quality in deep aquifers of Southern Bangladesh: the case against sustainable abstraction.

Science.gov (United States)

Ravenscroft, P; McArthur, J M; Hoque, M A

2013-06-01

In forty six wells >150 m deep, from across the arsenic-polluted area of south-central Bangladesh, groundwater composition remained unchanged between 1998 and 2011. No evidence of deteriorating water quality was found in terms of arsenic, iron, manganese, boron, barium or salinity over this period of 13 years. These deep tubewells have achieved operating lives of more than 20 years with minimal institutional support. These findings confirm that tubewells tapping the deep aquifers in the Bengal Basin provide a safe, popular, and economic, means of arsenic mitigation and are likely to do so for decades to come. Nevertheless, concerns remain about the sustainability of a resource that could serve as a source of As-safe water to mitigate As-pollution in shallower aquifers in an area where tens of millions of people are exposed to dangerous levels of arsenic in well water. The conjunction of the stable composition in deep groundwater and the severe adverse health effects of arsenic in shallow groundwater lead us to challenge the notion that strong sustainability principles should be applied to the management of deep aquifer abstraction in Bangladesh is, the notion that the deep groundwater resource should be preserved for future generations by protecting it from adverse impacts, probably of a minor nature, that could occur after a long time and might not happen at all. Instead, we advocate an ethical approach to development of the deep aquifer, based on adaptive abstraction management, which allows possibly unsustainable exploitation now in order to alleviate crippling disease and death from arsenic today while also benefiting future generations by improving the health, education and economy of living children. Copyright © 2013 Elsevier B.V. All rights reserved.

Removal of arsenic from drinking water by the electrocoagulation using Fe and Al electrodes

International Nuclear Information System (INIS)

Kobya, M.; Gebologlu, U.; Ulu, F.; Oncel, S.; Demirbas, E.

2011-01-01

Highlights: → Removal percentages of arsenic from drinking water at optimum operating conditions in electrocoagulation process were 93.5% for Fe electrode and 95.7% for Al electrode. → Operating costs at the optimum conditions were 0.020 Euro m -3 for Fe and 0.017 Euro m -3 for Al electrodes. → Surface topography of the solid particles at Fe/Al electrodes was analyzed with scanning electron microscope. → The adsorption of arsenic followed pseudo second-order adsorption model. - Abstract: A novel technique of electrocoagulation (EC) was attempted in the present investigation to remove arsenic from drinking waters. Experiments were carried out in a batch electrochemical reactor using Al and Fe electrodes with monopolar parallel electrode connection mode to assess their efficiency. The effects of several operating parameters on arsenic removal such as pH (4-9), current density (2.5-7.5 A m -2 ), initial concentration (75-500 μg L -1 ) and operating time (0-15 min) were examined. Optimum operating conditions were determined as an operating time of 12.5 min and pH 6.5 for Fe electrode (93.5%) and 15 min and pH 7 for Al electrode (95.7%) at 2.5 A m -2 , respectively. Arsenic removal obtained was highest with Al electrodes. Operating costs at the optimum conditions were calculated as 0.020 Euro m -3 for Fe and 0.017 Euro m -3 for Al electrodes. EC was able to bring down aqueous phase arsenic concentration to less than 10 μg L -1 with Fe and Al electrodes. The adsorption of arsenic over electrochemically produced hydroxides and metal oxide complexes was found to follow pseudo second-order adsorption model. Scanning electron microscopy was also used to analyze surface topography of the solid particles at Fe/Al electrodes during the EC process.

Removal of arsenic from drinking water by the electrocoagulation using Fe and Al electrodes

Energy Technology Data Exchange (ETDEWEB)

Kobya, M., E-mail: kobya@gyte.edu.tr [Gebze Institute of Technology, Department of Environmental Engineering, 41400 Gebze (Turkey); Gebologlu, U.; Ulu, F.; Oncel, S. [Gebze Institute of Technology, Department of Environmental Engineering, 41400 Gebze (Turkey); Demirbas, E. [Gebze Institute of Technology, Department of Chemistry, 41400 Gebze (Turkey)

2011-05-30

Highlights: > Removal percentages of arsenic from drinking water at optimum operating conditions in electrocoagulation process were 93.5% for Fe electrode and 95.7% for Al electrode. > Operating costs at the optimum conditions were 0.020 Euro m{sup -3} for Fe and 0.017 Euro m{sup -3} for Al electrodes. > Surface topography of the solid particles at Fe/Al electrodes was analyzed with scanning electron microscope. > The adsorption of arsenic followed pseudo second-order adsorption model. - Abstract: A novel technique of electrocoagulation (EC) was attempted in the present investigation to remove arsenic from drinking waters. Experiments were carried out in a batch electrochemical reactor using Al and Fe electrodes with monopolar parallel electrode connection mode to assess their efficiency. The effects of several operating parameters on arsenic removal such as pH (4-9), current density (2.5-7.5 A m{sup -2}), initial concentration (75-500 {mu}g L{sup -1}) and operating time (0-15 min) were examined. Optimum operating conditions were determined as an operating time of 12.5 min and pH 6.5 for Fe electrode (93.5%) and 15 min and pH 7 for Al electrode (95.7%) at 2.5 A m{sup -2}, respectively. Arsenic removal obtained was highest with Al electrodes. Operating costs at the optimum conditions were calculated as 0.020 Euro m{sup -3} for Fe and 0.017 Euro m{sup -3} for Al electrodes. EC was able to bring down aqueous phase arsenic concentration to less than 10 {mu}g L{sup -1} with Fe and Al electrodes. The adsorption of arsenic over electrochemically produced hydroxides and metal oxide complexes was found to follow pseudo second-order adsorption model. Scanning electron microscopy was also used to analyze surface topography of the solid particles at Fe/Al electrodes during the EC process.

Is arsenic biotransformation a detoxification mechanism for microorganisms?

Energy Technology Data Exchange (ETDEWEB)

Rahman, M. Azizur, E-mail: Mohammad.Rahman@uts.edu.au [Centre for Environmental Sustainability, School of the Environment, Faculty of Science, University of Technology, P.O. Box 123, Broadway, Sydney, NSW 2007 (Australia); Hassler, Christel [Marine and Lake Biogeochemistry, Institute F. A. Forel, University of Geneva, 10 rte de Suisse, Versoix, 1290 Switzerland (Switzerland)

2014-01-15

Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As{sup V}, which is thermodynamically stable in oxic waters, and As{sup III}, which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As{sup V}, biotransform it to As{sup III}, then biomethylate it to methylarsenic (MetAs) forms. Although As{sup III} is more toxic than As{sup V}, As{sup III} is much more easily excreted from the cells than As{sup V}. Therefore, majority of researchers consider the reduction of As{sup V} to As{sup III} as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA{sup V}, dimethylarsonate; DMA{sup V}, and trimethylarsenic oxide; TMAO{sup V}) and trimethylarsine (TMAO{sup III}). However, biomethylation by microorganisms also produces monomethylarsenite (MMA{sup III}) and dimethylarsenite (DMA{sup III}), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data.

Arsenic in Drinking Water-A Global Environmental Problem

Science.gov (United States)

Wang, Joanna Shaofen; Wai, Chien M.

2004-01-01

Information on the worldwide occurrence of groundwater pollution by arsenic, the ensuing health hazards, and the debatable government regulations of arsenic in drinking water, is presented. Diagnostic identification of arsenic, and methods to eliminate it from water are also discussed.

Screening and characterization of useful microorganisms to arsenic removal

OpenAIRE

宮武, 宗利; 林, 幸男

2007-01-01

Microorganisms were isolated from soil and their arsenic removal abilities were evaluated. Seven out of the 100 isolated strains showed more than 20% arsenic removal. Time courses of arsenic removal and cell growth were investigated in three of these isolated strains. Although the growth rates were different, the dependence of arsenic removal on cell growth was similar in three strains (A-84, 88, 89). Strain A-89 showed highest arsenic removal rate of 63% after first day. Strain A-88 was best...

Concentrations and chemical species of arsenic in human urine and hair

Energy Technology Data Exchange (ETDEWEB)

Yamato, Naohisa (St. Marianna Univ. School of Medicine, Kawasaki (Japan))

1988-05-01

Because marine products are rich in arsenic, the concentration of arsenic in the human urine varies greatly with the state of ingestion of marine products. It has been revealed that inorganic arsenic is methylated in the human body to form MAA (methylarsonic acid) and DMAA (dimethylarsinic acid). It appears therefore that the arsenic present in the human urine is a mixture of the arsenic originating from marine products and the arsenic metabolized in vivo. Recent studies have shown that inorganic arsenic and methylarsenic compounds are quite different in toxicity and effect on the living body due to their difference in chemical species. Finding the chemical species of arsenic in the urine and hair of normal subjects will therefore provide valuable basal data for the biological monitoring of arsenic exposure and for toxicological studies of arsenic.

Induction of Human Squamous Cell-Type Carcinomas by Arsenic

International Nuclear Information System (INIS)

Martinez, V. D.; Becker-Santos, D. D.; Vucic, E. A.; Lam, S.; Lam, W. L.

2011-01-01

Arsenic is a potent human carcinogen. Around one hundred million people worldwide have potentially been exposed to this metalloid at concentrations considered unsafe. Exposure occurs generally through drinking water from natural geological sources, making it difficult to control this contamination. Arsenic biotransformation is suspected to have a role in arsenic-related health effects ranging from acute toxicities to development of malignancies associated with chronic exposure. It has been demonstrated that arsenic exhibits preference for induction of squamous cell carcinomas in the human, especially skin and lung cancer. Interestingly, keratins emerge as a relevant factor in this arsenic-related squamous cell-type preference. Additionally, both genomic and epi genomic alterations have been associated with arsenic-driven neoplastic process. Some of these aberrations, as well as changes in other factors such as keratins, could explain the association between arsenic and squamous cell carcinomas in humans.

Arsenic removal from industrial effluent through electrocoagulation

Energy Technology Data Exchange (ETDEWEB)

Balasubramanian, N. [Central Electrochemical Research Inst., Karaikudi (India). Dept. of Pollution Control; Madhavan, K. [Coimbatore Inst. of Technology, Coimbatore (India). Dept. of Chemistry

2001-05-01

In the present investigation, it is attempted to remove arsenic from smelter industrial wastewater through electro-coagulation. Experiments covering a wide range of operating conditions for removal of the arsenic present in the smelter wastewater are carried out in a batch electrochemical reactor. It has been observed from the present work that arsenic can be removed effectively through electrocoagulation. (orig.)

Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

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Chen, Shih-Chieh; Chang, Chao-Yuah; Lin, Ming-Lu

2018-01-01

The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.

Arsenic removal in drinking water by reverse osmosis

OpenAIRE

Ahmad, Md. Fayej

2012-01-01

Arsenic is widely distributed in nature in the air, water and soil. Acute and chronic arsenic exposure by drinking water has been reported in many countries, especially Argentina, Bangladesh, India, Mexico, Mongolia, Thailand and Taiwan. There are many techniques used to remove arsenic from drinking water. Among them reverse osmosis is widely used. Therefore the purpose of this study is to find the conditions favorable for removal of arsenic from drinking water by using reverse osmosis ...

Chronic arsenic exposure increases TGFalpha concentration in bladder urothelial cells of Mexican populations environmentally exposed to inorganic arsenic

International Nuclear Information System (INIS)

Valenzuela, Olga L.; Germolec, Dori R.; Borja-Aburto, Victor H.; Contreras-Ruiz, Jose; Garcia-Vargas, Gonzalo G.; Razo, Luz M. del

2007-01-01

Inorganic arsenic (iAs) is a well-established carcinogen and human exposure has been associated with a variety of cancers including those of skin, lung, and bladder. High expression of transforming growth factor alpha (TGF-α) has associated with local relapses in early stages of urinary bladder cancer. iAs exposures are at least in part determined by the rate of formation and composition of iAs metabolites (MAs III , MAs V , DMAs III , DMAs V ). This study examines the relationship between TGF-α concentration in exfoliated bladder urothelial cells (BUC) separated from urine and urinary arsenic species in 72 resident women (18-51 years old) from areas exposed to different concentrations of iAs in drinking water (2-378 ppb) in central Mexico. Urinary arsenic species, including trivalent methylated metabolites were measured by hydride generation atomic absorption spectrometry method. The concentration of TGF-α in BUC was measured using an ELISA assay. Results show a statistically significant positive correlation between TGF-α concentration in BUC and each of the six arsenic species present in urine. The multivariate linear regression analyses show that the increment of TGF-α levels in BUC was importantly associated with the presence of arsenic species after adjusting by age, and presence of urinary infection. People from areas with high arsenic exposure had a significantly higher TGF-α concentration in BUC than people from areas of low arsenic exposure (128.8 vs. 64.4 pg/mg protein; p < 0.05). Notably, exfoliated cells isolated from individuals with skin lesions contained significantly greater amount of TGF-α than cells from individuals without skin lesions: 157.7 vs. 64.9 pg/mg protein (p = 0.003). These results suggest that TGF-α in exfoliated BUC may serve as a susceptibility marker of adverse health effects on epithelial tissue in arsenic-endemic areas

Linking geochemical processes in mud volcanoes with arsenic mobilization driven by organic matter.

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Liu, Chia-Chuan; Kar, Sandeep; Jean, Jiin-Shuh; Wang, Chung-Ho; Lee, Yao-Chang; Sracek, Ondra; Li, Zhaohui; Bundschuh, Jochen; Yang, Huai-Jen; Chen, Chien-Yen

2013-11-15

The present study deals with geochemical characterization of mud fluids and sediments collected from Kunshuiping (KSP), Liyushan (LYS), Wushanting (WST), Sinyangnyuhu (SYNH), Hsiaokunshui (HKS) and Yenshuikeng (YSK) mud volcanoes in southwestern Taiwan. Chemical constituents (cations, anions, trace elements, organic carbon, humic acid, and stable isotopes) in both fluids and mud were analyzed to investigate the geochemical processes and spatial variability among the mud volcanoes under consideration. Analytical results suggested that the anoxic mud volcanic fluids are highly saline, implying connate water as the probable source. The isotopic signature indicated that δ(18)O-rich fluids may be associated with silicate and carbonate mineral released through water-rock interaction, along with dehydration of clay minerals. Considerable amounts of arsenic in mud irrespective of fluid composition suggested possible release through biogeochemical processes in the subsurface environment. Sequential extraction of As from the mud indicated that As was mostly present in organic and sulphidic phases, and adsorbed on amorphous Mn oxyhydroxides. Volcanic mud and fluids are rich in organic matter (in terms of organic carbon), and the presence of humic acid in mud has implications for the binding of arsenic. Functional groups of humic acid also showed variable sources of organic matter among the mud volcanoes being examined. Because arsenate concentration in the mud fluids was found to be independent from geochemical factors, it was considered that organic matter may induce arsenic mobilization through an adsorption/desorption mechanism with humic substances under reducing conditions. Organic matter therefore plays a significant role in the mobility of arsenic in mud volcanoes. Copyright © 2012 Elsevier B.V. All rights reserved.

Attenuation of arsenic neurotoxicity by curcumin in rats

International Nuclear Information System (INIS)

Yadav, Rajesh S.; Sankhwar, Madhu Lata; Shukla, Rajendra K.; Chandra, Ramesh; Pant, Aditya B.; Islam, Fakhrul; Khanna, Vinay K.

2009-01-01

In view of continued exposure to arsenic and associated human health risk including neurotoxicity, neuroprotective efficacy of curcumin, a polyphenolic antioxidant, has been investigated in rats. A significant decrease in locomotor activity, grip strength (26%) and rota-rod performance (82%) was observed in rats treated with arsenic (sodium arsenite, 20 mg/kg body weight, p.o., 28 days) as compared to controls. The arsenic treated rats also exhibited a decrease in the binding of striatal dopamine receptors (32%) and tyrosine hydroxylase (TH) immunoreactivity (19%) in striatum. Increased arsenic levels in corpus striatum (6.5 fold), frontal cortex (6.3 fold) and hippocampus (7.0 fold) associated with enhanced oxidative stress in these brain regions, as evident by an increase in lipid perioxidation, protein carbonyl and a decrease in the levels of glutathione and activity of superoxide dismutase, catalase and glutathione peroxidase with differential effects were observed in arsenic treated rats compared to controls. Simultaneous treatment with arsenic (sodium arsenite, 20 mg/kg body weight, p.o., 28 days) and curcumin (100 mg/kg body weight, p.o., 28 days) caused an increase in locomotor activity and grip strength and improved the rota-rod performance in comparison to arsenic treated rats. Binding of striatal dopamine receptors and TH expression increased while arsenic levels and oxidative stress decreased in these brain regions in co-treated rats as compared to those treated with arsenic alone. No significant effect on any of these parameters was observed in rats treated with curcumin (100 mg/kg body weight, p.o., 28 days) alone compared to controls. A significant protection in behavioral, neurochemical and immunohistochemical parameters in rats simultaneously treated with arsenic and curcumin suggest the neuroprotective efficacy of curcumin.

Distribution of microbial arsenic reduction, oxidation and extrusion genes along a wide range of environmental arsenic concentrations.

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Lorena V Escudero

Full Text Available The presence of the arsenic oxidation, reduction, and extrusion genes arsC, arrA, aioA, and acr3 was explored in a range of natural environments in northern Chile, with arsenic concentrations spanning six orders of magnitude. A combination of primers from the literature and newly designed primers were used to explore the presence of the arsC gene, coding for the reduction of As (V to As (III in one of the most common detoxification mechanisms. Enterobacterial related arsC genes appeared only in the environments with the lowest As concentration, while Firmicutes-like genes were present throughout the range of As concentrations. The arrA gene, involved in anaerobic respiration using As (V as electron acceptor, was found in all the systems studied. The As (III oxidation gene aioA and the As (III transport gene acr3 were tracked with two primer sets each and they were also found to be spread through the As concentration gradient. Sediment samples had a higher number of arsenic related genes than water samples. Considering the results of the bacterial community composition available for these samples, the higher microbial phylogenetic diversity of microbes inhabiting the sediments may explain the increased number of genetic resources found to cope with arsenic. Overall, the environmental distribution of arsenic related genes suggests that the occurrence of different ArsC families provides different degrees of protection against arsenic as previously described in laboratory strains, and that the glutaredoxin (Grx-linked arsenate reductases related to Enterobacteria do not confer enough arsenic resistance to live above certain levels of As concentrations.

Study of arsenic accumulation in rice and evaluation of protective effects of Chorchorus olitorius leaves against arsenic contaminated rice induced toxicities in Wistar albino rats.

Science.gov (United States)

Hosen, Saeed Mohammed Imran; Das, Dipesh; Kobi, Rupkanowar; Chowdhury, Dil Umme Salma; Alam, Md Jibran; Rudra, Bashudev; Bakar, Muhammad Abu; Islam, Saiful; Rahman, Zillur; Al-Forkan, Mohammad

2016-10-14

In the present study, we investigated the arsenic accumulation in different parts of rice irrigated with arsenic contaminated water. Besides, we also evaluated the protective effects of Corchorus olitorius leaves against arsenic contaminated rice induced toxicities in animal model. A pot experiment was conducted with arsenic amended irrigation water (0.0, 25.0, 50.0 and 75.0 mg/L As) to investigate the arsenic accumulation in different parts of rice. In order to evaluate the protective effects of Corchorus olitorius leaves, twenty Wistar albino rats were divided into four different groups. The control group (Group-I) was supplied with normal laboratory pellets while groups II, III, and IV received normal laboratory pellets supplemented with arsenic contaminated rice, C. olitorius leaf powder (4 %), arsenic contaminated rice plus C. olitorius leaf powder (4 %) respectively. Different haematological parameters and serum indices were analyzed to evaluate the protective effects of Corchorus olitorius leaves against arsenic intoxication. To gather more supportive evidences of Corchorus olitorius potentiality against arsenic intoxication, histopathological analysis of liver, kidney, spleen and heart tissues was also performed. From the pot experiment, we have found a significant (p ≤ 0.05) increase of arsenic accumulation in different parts of rice with the increase of arsenic concentrations in irrigation water and the trend of accumulation was found as root > straw > husk > grain. Another part of the experiment revealed that supplementation of C. olitorius leaves with arsenic contaminated rice significantly (p rice induced toxicities. Arsenic accumulation in different parts of rice increased dose-dependently. Hence, for irrigation purpose arsenic contaminated water cannot be used. Furthermore, arsenic contaminated rice induced several toxicities in animal model, most of which could be minimized with the food supplementation of Corchorus olitorius

Slow arsenic poisoning of the contaminated groundwater users

International Nuclear Information System (INIS)

Uddin, M. M.; Harun-Ar-Rashid, A. K. M.; Hossain, S. M.; Hafiz, M. A.; Nahar, K.; Mubin, S. H.

2006-01-01

This paper gives impact of Arsenic contaminated water on human health as well as overview of the extent and severity of groundwater arsenic contamination in Bangladesh. Scalp hair is the most important part of the human body to monitor the accumulation of this type of poison. Therefore, an experiment has been carried out by Neutron Activation Analysis at Atomic Energy Research Establishment , Savar, Dhaka, Bangladesh on human hair of corresponding tube well water users of these areas to determine the total accumulation of arsenic to their body. Hair samples collected from the region where the groundwater was found highly contaminated with arsenic. The obtained results of arsenic concentration in the lower age (Hb) categories of users (below 12 years of age users) is in the range of 0.33 to 3.29 μg/g (ppm) and that in the Hu categories (upper 12 years of age users) is 0.47 to 6.64 μg/g (ppm). Where as maximum permissible range is 1 ppm certified from WHO. Results show that the peoples are highly affected where the groundwater is highly contaminated with arsenic and acts as the primary source of arsenic poisoning among the peoples of those areas. The results indicate that human population is affected with arsenic locally using the contaminated water for a long time

Association of Low-Moderate Arsenic Exposure and Arsenic Metabolism with Incident Diabetes and Insulin Resistance in the Strong Heart Family Study.

Science.gov (United States)

Grau-Perez, Maria; Kuo, Chin-Chi; Gribble, Matthew O; Balakrishnan, Poojitha; Jones Spratlen, Miranda; Vaidya, Dhananjay; Francesconi, Kevin A; Goessler, Walter; Guallar, Eliseo; Silbergeld, Ellen K; Umans, Jason G; Best, Lyle G; Lee, Elisa T; Howard, Barbara V; Cole, Shelley A; Navas-Acien, Ana

2017-12-20

High arsenic exposure has been related to diabetes, but at low-moderate levels the evidence is mixed. Arsenic metabolism, which is partly genetically controlled and may rely on certain B vitamins, plays a role in arsenic toxicity. We evaluated the prospective association of arsenic exposure and metabolism with type 2 diabetes and insulin resistance. We included 1,838 American Indian men and women free of diabetes (median age, 36 y). Arsenic exposure was assessed as the sum of inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) urine concentrations (ΣAs). Arsenic metabolism was evaluated by the proportions of iAs, MMA, and DMA over their sum (iAs%, MMA%, and DMA%). Homeostasis model assessment for insulin resistance (HOMA2-IR) was measured at baseline and follow-up visits. Incident diabetes was evaluated at follow-up. Median ΣAs, iAs%, MMA%, and DMA% was 4.4 μg/g creatinine, 9.5%, 14.4%, and 75.6%, respectively. Over 10,327 person-years of follow-up, 252 participants developed diabetes. Median HOMA2-IR at baseline was 1.5. The fully adjusted hazard ratio [95% confidence interval (CI)] for incident diabetes per an interquartile range increase in ΣAs was 1.57 (95% CI: 1.18, 2.08) in participants without prediabetes at baseline. Arsenic metabolism was not associated with incident diabetes. ΣAs was positively associated with HOMA2-IR at baseline but negatively with HOMA2-IR at follow-up. Increased MMA% was associated with lower HOMA2-IR when either iAs% or DMA% decreased. The association of arsenic metabolism with HOMA2-IR differed by B-vitamin intake and AS3MT genetics variants. Among participants without baseline prediabetes, arsenic exposure was associated with incident diabetes. Low MMA% was cross-sectional and prospectively associated with higher HOMA2-IR. Research is needed to confirm possible interactions of arsenic metabolism with B vitamins and AS3MT variants on diabetes risk. https://doi.org/10.1289/EHP2566.

Use of arsenic-73 in research supports USEPA's regulatory decisions on inorganic arsenic in drinking water*

Science.gov (United States)

Inorganic arsenic is a natural contaminant of drinking water in the United States and throughout the world. Long term exposure to inorganic arsenic in drinking water at elevated levels (>100 ug/L) is associated with development of cancer in several organs, cardiovascular disease,...

Bacteria-mediated arsenic oxidation and reduction in the growth media of arsenic hyperaccumulator Pteris vittata.

Science.gov (United States)

Wang, Xin; Rathinasabapathi, Bala; de Oliveira, Letuzia Maria; Guilherme, Luiz R G; Ma, Lena Q

2012-10-16

Microbes play an important role in arsenic transformation and cycling in the environment. Microbial arsenic oxidation and reduction were demonstrated in the growth media of arsenic hyperaccumulator Pteris vittata L. All arsenite (AsIII) at 0.1 mM in the media was oxidized after 48 h incubation. Oxidation was largely inhibited by antibiotics, indicating that bacteria played a dominant role. To identify AsIII oxidizing bacteria, degenerate primers were used to amplify ∼500 bp of the AsIII oxidase gene aioA (aroA) using DNA extracted from the media. One aioA (aroA)-like sequence (MG-1, tentatively identified as Acinetobacter sp.) was amplified, exhibiting 82% and 91% identity in terms of gene and deduced protein sequence to those from Acinetobacter sp. 33. In addition, four bacterial strains with different arsenic tolerance were isolated and identified as Comamonas sp.C-1, Flavobacterium sp. C-2, Staphylococcus sp. C-3, and Pseudomonas sp. C-4 using carbon utilization, fatty acid profiles, and/or sequencing 16s rRNA gene. These isolates exhibited dual capacity for both AsV reduction and AsIII oxidation under ambient conditions. Arsenic-resistant bacteria with strong AsIII oxidizing ability may have potential to improve bioremediation of AsIII-contaminated water using P. vittata and/or other biochemical strategies.

Arsenic and mercury partitioning in fly ash at a Kentucky power plant

Energy Technology Data Exchange (ETDEWEB)

Tanaporn Sakulpitakphon; James C. Hower; Alan S. Trimble; William H. Schram; Gerald A. Thomas [University of Kentucky, Lexington, KY (United States). Center for Applied Energy Research

2003-08-01

Coal and fly ash samples were collected from a 500-MW unit at a Kentucky power plant, with the objective of studying the distribution of arsenic, mercury, and other trace elements in fly ash. The coal feed was low-sulfur, high volatile A bituminous central West Virginia coal. The plant produced a relatively low-carbon fly ash. In contrast to power plants with high-mercury feed coal, the fly ashes from the lower-mercury feed coal had low mercury values, generally not exceeding 0.01 ppm Hg. Mercury capture by fly ash varies with both the amount and type of carbon and the collection temperature; mercury capture is more efficient at lower temperatures. Arsenic in the feed coal and in the flue gas is of concern to the utility, because of the potential for catalyst poisoning in the selective catalytic reduction system (in the planning stage at the time of the sampling). Arsenic is captured in the fly ash, increasing in concentration in the more-distant (from the boiler) reaches of the electrostatic precipitator system. 16 refs., 2 figs., 5 tabs.

Biological and environmental hazards associated with exposure to chemical warfare agents: arsenicals.

Science.gov (United States)

Li, Changzhao; Srivastava, Ritesh K; Athar, Mohammad

2016-08-01

Arsenicals are highly reactive inorganic and organic derivatives of arsenic. These chemicals are very toxic and produce both acute and chronic tissue damage. On the basis of these observations, and considering the low cost and simple methods of their bulk syntheses, these agents were thought to be appropriate for chemical warfare. Among these, the best-known agent that was synthesized and weaponized during World War I (WWI) is Lewisite. Exposure to Lewisite causes painful inflammatory and blistering responses in the skin, lung, and eye. These chemicals also manifest systemic tissue injury following their cutaneous exposure. Although largely discontinued after WWI, stockpiles are still known to exist in the former Soviet Union, Germany, Italy, the United States, and Asia. Thus, access by terrorists or accidental exposure could be highly dangerous for humans and the environment. This review summarizes studies that describe the biological, pathophysiological, toxicological, and environmental effects of exposure to arsenicals, with a major focus on cutaneous injury. Studies related to the development of novel molecular pathobiology-based antidotes against these agents are also described. © 2016 New York Academy of Sciences.

Biological and environmental hazards associated with exposure to chemical warfare agents: arsenicals

Science.gov (United States)

Li, Changzhao; Srivastava, Ritesh K.; Athar, Mohammad

2016-01-01

Arsenicals are highly reactive inorganic and organic derivatives of arsenic. These chemicals are very toxic and produce both acute and chronic tissue damage. Based on these observations, and considering the low cost and simple methods of their bulk syntheses, these agents were thought to be appropriate for chemical warfare. Among these, the most known agent synthesized and weaponized during World War I (WWI) is Lewisite. Exposure to Lewisite causes painful inflammatory and blistering responses in the skin, lung, and eye. These chemicals also manifest systemic tissue injury following their cutaneous exposure. Although largely discontinued after WWI, their stockpiles are still known to exist in the former Soviet Union, Germany, Italy, the United States, and Asia. Thus, their access by terrorists or accidental exposure could be highly dangerous for humans and the environment. This review summarizes studies which describe the biological, pathophysiological, toxicological, and environmental effects of exposure to arsenicals, with a major focus on cutaneous injury. Studies related to the development of novel molecular pathobiology–based antidotes against these agents are also described. PMID:27636894

[Effect of glutathione and sodium selenite on the metabolism of arsenic in mice exposed to arsenic through drinking water].

Science.gov (United States)

Yu, Xiao-Yun; Zhong, Yuan; Niu, Yu-Hong; Qu, Chun-Qing; Li, Ge-Xin; Lü, Xiu-Qiang; Sun, Gui-Fan; Jin, Ya-Ping

2008-09-01

To explore the effect of glutathione (GSH) and sodium selenite on the metabolism of arsenic in the liver, kidney and blood of mice exposed to iAsIII through drinking water. The mice were randomly divided into control, arsenic, GSH and sodium selenite group, respectively. And each group had eight mice and the mice were exposed to 50 mg/L arsenite by drinking water for 4 weeks. Mice were intraperitoneally injected with GSH (600 mg/kg) and sodium selenite (1 mg/kg) for seven days from the beginning of the fourth week. At the end of the fourth week, liver, kidney and blood were sampled to assess the concentrations of inorganic arsenic (iAs), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA) by hydride generation trapping by ultra-hypothermia coupled with atomic absorption spectrometry. The liver DMA (233.76 +/- 60.63 ng/g) concentration in GSH group was significantly higher than the arsenic group (218.36 +/- 42.71 ng/g). The concentration of DMA (88.52 +/- 30.86 ng/g) and total arsenic (TAs) (162.32 +/- 49.45 ng/g) in blood of GSH group was significantly higher than those [(45.32 +/- 12.19 ng/g), (108.51 +/- 18.00 ng/g), respectively] of arsenic groups(q values were 3.06, 6.40, 10.72 respectively, P < 0.05). The primary methylated index (PMI) (0.65 +/- 0.050) and secondary methylated index (SMI) (0.55 +/- 0.050) in liver sample of GSH group were significantly higher than those (0.58 +/- 0.056, 0.44 +/- 0. 093) in arsenic group. In blood samples, the PMI (0.85 +/- 0.066) in GSH group was significantly higher than that (0.54 +/- 0.113) in arsenic group (q values were 3.75, 5.26, 4.21 respectively, P < 0.05). However, no significant difference was identified between sodium selenite and arsenic groups in liver, kidney or blood samples. And no significant difference was detected in kidney samples among all arsenic exposing groups. Exogenous GSH could promote the methylated metabolism of iAsIII, but sodium selenite showed no significant effects.

Simultaneous arsenic and fluoride removal from synthetic and real groundwater by electrocoagulation process: Parametric and cost evaluation.

Science.gov (United States)

Thakur, Lokendra Singh; Mondal, Prasenjit

2017-04-01

Co-existence of arsenic and fluoride in groundwater has raised severe health issues to living being. Thus, the present research has been conducted for simultaneous removal of arsenic and fluoride from synthetic groundwater by using electrocoagulation process with aluminum electrode. Effects of initial pH, current density, run time, inter electrode distance and NaCl concentration over percentage removal of arsenic and fluoride as well as operating cost have been studied. The optimum experimental conditions are found to be initial pH: 7, current density: 10 A/m 2 , run time: 95 min, inter electrode distance: 1 cm, NaCl concentration: 0.71 g/l for removal of 98.51% arsenic (initial concentration: 550 μg/l) and 88.33% fluoride (initial concentration: 12 mg/l). The concentration of arsenic and fluoride in treated water are found to be 8.19 μg/l and 1.4 mg/l, respectively, with an operating cost of 0.357 USD/m 3 treated water. Pseudo first and second order kinetic model of individual and simultaneous arsenic and fluoride removal in electrocoagulation have also been studied. Produced sludge characterization studies also confirm the presence of arsenic in As(III) form, and fluoride in sludge. The present electrocoagulation process is able to reduce the arsenic and fluoride concentration of synthetic as well as real groundwater to below 10 μg/l and 1.5 mg/l, respectively, which are maximum contaminant level of these elements in drinking water according to WHO guidelines. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aquatic arsenic: phytoremediation using floating macrophytes.

Science.gov (United States)

Rahman, M Azizur; Hasegawa, H

2011-04-01

Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Relationship between arsenic skin lesions and the age of natural menopause.

Science.gov (United States)

Yunus, Fakir Md; Rahman, Musarrat Jabeen; Alam, Md Zahidul; Hore, Samar Kumar; Rahman, Mahfuzar

2014-05-02

Chronic exposure to arsenic is associated with neoplastic, cardiovascular, endocrine, neuro-developmental disorders and can have an adverse effect on women's reproductive health outcomes. This study examined the relationship between arsenic skin lesions (a hallmark sign of chronic arsenic poisoning) and age of natural menopause (final menopausal period) in populations with high levels of arsenic exposure in Bangladesh. We compared menopausal age in two groups of women--with and without arsenic skin lesions; and presence of arsenic skin lesions was used as an indicator for chronic arsenic exposure. In a cross-sectional study, a total of 210 participants were randomly identified from two ongoing studies--participants with arsenic skin lesions were identified from an ongoing clinical trial and participants with no arsenic skin lesions were identified from an ongoing cohort study. Mean age of menopause between these two groups were calculated and compared. Multivariable linear regression was used to estimate the relationship between the status of the arsenic skin lesions and age of natural menopause in women. Women with arsenic skin lesions were 1.5 years younger (p <0.001) at the time of menopause compared to those without arsenic skin lesions. After adjusting with contraceptive use, body mass index, urinary arsenic level and family history of premature menopause, the difference between the groups' age at menopause was 2.1 years earlier (p <0.001) for respondents with arsenic skin lesions. The study showed a statistically significant association between chronic exposure to arsenic and age at menopause. Heavily exposed women experienced menopause two years earlier than those with lower or no exposure.

An insight of environmental contamination of arsenic on animal health

Directory of Open Access Journals (Sweden)

Paramita Mandal

2017-03-01

Full Text Available The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. Exposure to arsenic is mainly via intake of food and drinking water, food being the most important source in most populations. Although adverse health effects of heavy metals have been known for a long time, exposure to heavy metals continues and is even increasing in some areas. Long-term exposure to arsenic in drinking-water is mainly related to increased risks of skin cancer, but also some other cancers, as well as other skin lesions such as hyperkeratosis and pigmentation changes. Therefore, measures should be taken to reduce arsenic exposure in the general population in order to minimize the risk of adverse health effects. Animal are being exposed to arsenic through contaminated drinking water, feedstuff, grasses, vegetables and different leaves. Arsenic has been the most common causes of inorganic chemical poisoning in farm animals. Although, sub-chronic and chronic exposure of arsenic do not generally reveal external signs or symptoms in farm animals but arsenic (or metabolites concentrations in blood, hair, hoofs and urine are remained high in animals of arsenic contaminated zones. So it is assumed that concentration of arsenic in blood, urine, hair or milk have been used as biomarkers of arsenic exposure in field animals.

Genomic responses to arsenic in the cyanobacterium Synechocystis sp. PCC 6803.

Directory of Open Access Journals (Sweden)

Ana María Sánchez-Riego

Full Text Available Arsenic is a ubiquitous contaminant and a toxic metalloid which presents two main redox states in nature: arsenite [As(III] and arsenate [As(V]. Arsenic resistance in Synechocystis sp. strain PCC 6803 is mediated by the arsBHC operon and two additional arsenate reductases encoded by the arsI1 and arsI2 genes. Here we describe the genome-wide responses to the presence of arsenate and arsenite in wild type and mutants in the arsenic resistance system. Both forms of arsenic produced similar responses in the wild type strain, including induction of several stress related genes and repression of energy generation processes. These responses were transient in the wild type strain but maintained in time in an arsB mutant strain, which lacks the arsenite transporter. In contrast, the responses observed in a strain lacking all arsenate reductases were somewhat different and included lower induction of genes involved in metal homeostasis and Fe-S cluster biogenesis, suggesting that these two processes are targeted by arsenite in the wild type strain. Finally, analysis of the arsR mutant strain revealed that ArsR seems to only control 5 genes in the genome. Furthermore, the arsR mutant strain exhibited hypersentivity to nickel, copper and cadmium and this phenotype was suppressed by mutation in arsB but not in arsC gene suggesting that overexpression of arsB is detrimental in the presence of these metals in the media.

Method development for arsenic analysis by modification in spectrophotometric technique

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M. A. Tahir

2012-01-01

Full Text Available Arsenic is a non-metallic constituent, present naturally in groundwater due to some minerals and rocks. Arsenic is not geologically uncommon and occurs in natural water as arsenate and arsenite. Additionally, arsenic may occur from industrial discharges or insecticide application. World Health Organization (WHO and Pakistan Standard Quality Control Authority have recommended a permissible limit of 10 ppb for arsenic in drinking water. Arsenic at lower concentrations can be determined in water by using high tech instruments like the Atomic Absorption Spectrometer (hydride generation. Because arsenic concentration at low limits of 1 ppb can not be determined easily with simple spectrophotometric technique, the spectrophotometric technique using silver diethyldithiocarbamate was modified to achieve better results, up to the extent of 1 ppb arsenic concentration.

Reduction and Coordination of Arsenic in Indian Mustard1

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Pickering, Ingrid J.; Prince, Roger C.; George, Martin J.; Smith, Robert D.; George, Graham N.; Salt, David E.

2000-01-01

The bioaccumulation of arsenic by plants may provide a means of removing this element from contaminated soils and waters. However, to optimize this process it is important to understand the biological mechanisms involved. Using a combination of techniques, including x-ray absorption spectroscopy, we have established the biochemical fate of arsenic taken up by Indian mustard (Brassica juncea). After arsenate uptake by the roots, possibly via the phosphate transport mechanism, a small fraction is exported to the shoot via the xylem as the oxyanions arsenate and arsenite. Once in the shoot, the arsenic is stored as an AsIII-tris-thiolate complex. The majority of the arsenic remains in the roots as an AsIII-tris-thiolate complex, which is indistinguishable from that found in the shoots and from AsIII-tris-glutathione. The thiolate donors are thus probably either glutathione or phytochelatins. The addition of the dithiol arsenic chelator dimercaptosuccinate to the hydroponic culture medium caused a 5-fold-increased arsenic level in the leaves, although the total arsenic accumulation was only marginally increased. This suggests that the addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element. PMID:10759512

Ecotoxicology of arsenic in the marine environment

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Neff, J.M. [Battelle Ocean Sciences Lab., Duxbury, MA (United States)

1997-05-01

Arsenic has a complex marine biogeochemistry that has important implications for its toxicity to marine organisms and their consumers. The average concentration of total arsenic in the ocean is about 1.7 {micro}g/L, about two orders of magnitude higher than the US Environmental Protection Agency`s human health criterion value of 0.0175 {micro}g/L. The dominant form of arsenic in oxygenated marine and brackish waters in arsenate (As V). The more toxic and potentially carcinogenic arsenite (As III) rarely accounts for more than 20% of total arsenic in seawater. Uncontaminated marine sediments contain from 5 to about 40 {micro}g/g dry weight total arsenic. Arsenate dominates in oxidized sediments and is associated primarily with iron oxyhydroxides. In reducing marine sediments, arsenate is reduced to arsenite and is associated primarily with sulfide minerals. Marine algae accumulate arsenate from seawater, reduce it to arsenite, and then oxidize the arsenite to a large number of organoarsenic compounds. The algae release arsenite, methylarsonic acid, and dimethylarsinic acid to seawater. Dissolved arsenite and arsenate are more toxic to marine phytoplankton than to marine invertebrates and fish. This may be due to the fact that marine animals have a limited ability to bioconcentrate inorganic arsenic from seawater but can bioaccumulate organoarsenic compounds from their food. Tissues of marine invertebrates and fish contain high concentrations of arsenic, usually in the range of about 1 to 100 {micro}g/g dry weight, most of it in the form of organoarsenic compounds, particularly arsenobetaine. Organoarsenic compounds are bioaccumulated by human consumers of seafood products, but the arsenic is excreted rapidly, mostly as organoarsenic compounds. Arsenobetaine, the most abundant organoarsenic compound in seafoods, is not toxic or carcinogenic to mammals. Little of the organoarsenic accumulated by humans from seafood is converted to toxic inorganic arsenite.

Total arsenic in selected food samples from Argentina: Estimation of their contribution to inorganic arsenic dietary intake.

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Sigrist, Mirna; Hilbe, Nandi; Brusa, Lucila; Campagnoli, Darío; Beldoménico, Horacio

2016-11-01

An optimized flow injection hydride generation atomic absorption spectroscopy (FI-HGAAS) method was used to determine total arsenic in selected food samples (beef, chicken, fish, milk, cheese, egg, rice, rice-based products, wheat flour, corn flour, oats, breakfast cereals, legumes and potatoes) and to estimate their contributions to inorganic arsenic dietary intake. The limit of detection (LOD) and limit of quantification (LOQ) values obtained were 6μgkg(-)(1) and 18μgkg(-)(1), respectively. The mean recovery range obtained for all food at a fortification level of 200μgkg(-)(1) was 85-110%. Accuracy was evaluated using dogfish liver certified reference material (DOLT-3 NRC) for trace metals. The highest total arsenic concentrations (in μgkg(-)(1)) were found in fish (152-439), rice (87-316) and rice-based products (52-201). The contribution to inorganic arsenic (i-As) intake was calculated from the mean i-As content of each food (calculated by applying conversion factors to total arsenic data) and the mean consumption per day. The primary contributors to inorganic arsenic intake were wheat flour, including its proportion in wheat flour-based products (breads, pasta and cookies), followed by rice; both foods account for close to 53% and 17% of the intake, respectively. The i-As dietary intake, estimated as 10.7μgday(-)(1), was significantly lower than that from drinking water in vast regions of Argentina. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diverse arsenic- and iron-cycling microbial communities in arsenic-contaminated aquifers used for drinking water in Bangladesh.

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Hassan, Zahid; Sultana, Munawar; van Breukelen, Boris M; Khan, Sirajul I; Röling, Wilfred F M

2015-04-01

Subsurface removal of arsenic by injection with oxygenated groundwater has been proposed as a viable technology for obtaining 'safe' drinking water in Bangladesh. While the oxidation of ferrous iron to solid ferric iron minerals, to which arsenic adsorbs, is assumed to be driven by abiotic reactions, metal-cycling microorganisms may potentially affect arsenic removal. A cultivation-independent survey covering 24 drinking water wells in several geographical regions in Bangladesh was conducted to obtain information on microbial community structure and diversity in general, and on specific functional groups capable of the oxidation or reduction of arsenic or iron. Each functional group, targeted by either group-specific 16S rRNA or functional gene amplification, occurred in at least 79% of investigated samples. Putative arsenate reducers and iron-oxidizing Gallionellaceae were present at low diversity, while more variation in potentially arsenite-oxidizing microorganisms and iron-reducing Desulfuromonadales was revealed within and between samples. Relations between community composition on the one hand and hydrochemistry on the other hand were in general not evident, apart from an impact of salinity on iron-cycling microorganisms. Our data suggest widespread potential for a positive contribution of arsenite and iron oxidizers to arsenic removal upon injection with oxygenated water, but also indicate a potential risk for arsenic re-mobilization by anaerobic arsenate and iron reducers once injection is halted. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Association of Arsenic Exposure and Arsenic Metabolism with the Metabolic Syndrome and its Individual Components: Prospective Evidence from the Strong Heart Family Study.

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Spratlen, Miranda J; Grau-Perez, Maria; Best, Lyle G; Yracheta, Joseph; Lazo, Mariana; Vaidya, Dhananjay; Balakrishnan, Poojitha; Gamble, Mary V; Francesconi, Kevin A; Goessler, Walter; Cole, Shelley A; Umans, Jason G; Howard, Barbara V; Navas-Acien, Ana

2018-03-15

Inorganic arsenic exposure is ubiquitous and both exposure and inter-individual differences in its metabolism have been associated with cardiometabolic risk. The association between arsenic exposure and arsenic metabolism with metabolic syndrome and its individual components, however, is relatively unknown. We used poisson regression with robust variance to evaluate the association between baseline arsenic exposure (urine arsenic levels) and metabolism (relative percentage of arsenic species over their sum) with incident metabolic syndrome and its individual components (elevated waist circumference, elevated triglycerides, reduced HDL, hypertension, elevated fasting plasma glucose) in 1,047 participants from the Strong Heart Family Study, a prospective family-based cohort in American Indian communities (baseline visits in 1998-1999 and 2001-2003, follow-up visits in 2001-2003 and 2006-2009). 32% of participants developed metabolic syndrome over follow-up. An IQR increase in arsenic exposure was associated with 1.19 (95% CI: 1.01, 1.41) greater risk for elevated fasting plasma glucose but not with other individual components or overall metabolic syndrome. Arsenic metabolism, specifically lower MMA% and higher DMA% was associated with higher risk of overall metabolic syndrome and elevated waist circumference, but not with any other component. These findings support there is a contrasting and independent association between arsenic exposure and arsenic metabolism with metabolic outcomes which may contribute to overall diabetes risk.

Reassessing the role of sulfur geochemistry on arsenic speciation in reducing environments

KAUST Repository

Couture, Raoul-Marie

2011-05-01

Recent evidence suggests that the oxidation of arsenite by zero-valent sulfur (S(0)) may produce stable aqueous arsenate species under highly reducing conditions. The speciation of arsenic (As) in reducing soils, sediments and aquifers may therefore be far more complex than previously thought. We illustrate this by presenting updated Eh-pH diagrams of As speciation in sulfidic waters that include the most recently reported formation constants for sulfide complexes of As(III) and As(V). The results show that the stability fields of As(III) and As(V) (oxy)thioanions cover a large pH range, from pH 5 to 10. In particular, As(V)-S(-II) complexes significantly enhance the predicted solubility of As under reducing conditions. Equilibrium calculations further show that, under conditions representative of sulfidic pore waters and in the presence of solid-phase elemental sulfur, the S0 (aq)/HS- couple yields a redox potential (Eh)~0.1V higher than the SO4 2-/HS- couple. S(0) may thus help stabilize aqueous As(V) not only by providing an electron acceptor for As(III) but also by contributing to a more oxidizing redox state. © 2011 Elsevier B.V.

Reassessing the role of sulfur geochemistry on arsenic speciation in reducing environments

KAUST Repository

Couture, Raoul-Marie; Van Cappellen, Philippe

2011-01-01

Recent evidence suggests that the oxidation of arsenite by zero-valent sulfur (S(0)) may produce stable aqueous arsenate species under highly reducing conditions. The speciation of arsenic (As) in reducing soils, sediments and aquifers may therefore be far more complex than previously thought. We illustrate this by presenting updated Eh-pH diagrams of As speciation in sulfidic waters that include the most recently reported formation constants for sulfide complexes of As(III) and As(V). The results show that the stability fields of As(III) and As(V) (oxy)thioanions cover a large pH range, from pH 5 to 10. In particular, As(V)-S(-II) complexes significantly enhance the predicted solubility of As under reducing conditions. Equilibrium calculations further show that, under conditions representative of sulfidic pore waters and in the presence of solid-phase elemental sulfur, the S0 (aq)/HS- couple yields a redox potential (Eh)~0.1V higher than the SO4 2-/HS- couple. S(0) may thus help stabilize aqueous As(V) not only by providing an electron acceptor for As(III) but also by contributing to a more oxidizing redox state. © 2011 Elsevier B.V.

Arsenic bioleaching in medical realgar ore and arsenicbearing ...

African Journals Online (AJOL)

However, the maximum arsenic leaching ratio from realgar in the presence of mixed unadapted strains was only 12.4 %. Besides, maximum arsenic leaching ratios from arsenic-bearing refractory gold ore by mixed adapted strains or unadapted strains were 45.0 and 22.9 %, respectively. Oxidation of these two ores by ...

Arsenic inhibits hedgehog signaling during P19 cell differentiation

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Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

2014-12-15

Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

Identification of Arsenic Direct-Binding Proteins in Acute Promyelocytic Leukaemia Cells

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Tao Zhang

2015-11-01

Full Text Available The identification of arsenic direct-binding proteins is essential for determining the mechanism by which arsenic trioxide achieves its chemotherapeutic effects. At least two cysteines close together in the amino acid sequence are crucial to the binding of arsenic and essential to the identification of arsenic-binding proteins. In the present study, arsenic binding proteins were pulled down with streptavidin and identified using a liquid chromatograph-mass spectrometer (LC-MS/MS. More than 40 arsenic-binding proteins were separated, and redox-related proteins, glutathione S-transferase P1 (GSTP1, heat shock 70 kDa protein 9 (HSPA9 and pyruvate kinase M2 (PKM2, were further studied using binding assays in vitro. Notably, PKM2 has a high affinity for arsenic. In contrast to PKM2, GSTP1and HSPA9 did not combine with arsenic directly in vitro. These observations suggest that arsenic-mediated acute promyelocytic leukaemia (APL suppressive effects involve PKM2. In summary, we identified several arsenic binding proteins in APL cells and investigated the therapeutic mechanisms of arsenic trioxide for APL. Further investigation into specific signal pathways by which PKM2 mediates APL developments may lead to a better understanding of arsenic effects on APL.

Alternative technology for arsenic removal from drinking water

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Purenović Milovan

2007-01-01

Full Text Available Arsenic is a naturally occurring element in water, food and air. It is known as a poison, but in very small quantities it is showed to be an essential element. Actual problem in the world is arsenic removal from drinking water using modern and alternative technology, especially because EPA's and other international standards have reduced MCL from 50 to 10 ug/1. Because of rivers and lakes pollution, in a number of plants for natural water purification, average concentrations of arsenic in water are up to 100 ug/1. According to MCL, present technologies are unadjusted for safely arsenic removal for concentrations below of 10 ug/1. This fact has inspired many companies to solve this problem adequately, by using an alternative technologies and new process able materials. In this paper the observation of conventional and the alternative technologies will be given, bearing in mind complex chemistry and electrochemistry of arsenic, formation of colloidal arsenic, which causes the biggest problems in water purification technologies. In this paper many results will be presented, which are obtained using the alternative technologies, as well as the newest results of original author's investigations. Using new nanomaterials, on Pilot plant "VALETA H2O-92", concentration of arsenic was removed far below MLC value.

Removal of Arsenic with Oyster Shell: Experimental Measurements

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Md. Atiqur Rahman, , and

2008-12-01

Full Text Available Oyster shell has tremendous potential as a remediation material for the removal of arsenic from groundwater. A single arsenic removal system was developed with oyster shell for tube well water containing arsenic. The system removes arsenic from water by adsorption through fine oyster shell. Various conditions that affect the adsorption/desorption of arsenic were investigated. Adsorption column methods showed the removal of As(III under the following conditions: initial As concentration, 100 µg /L; oyster shell amount, 6 g; particle size, <355µm ; treatment flow rate, 1.7 mL/min; and pH 6.5. Arsenic concentration of the treated water were below the Bangladesh drinking water standard of 50 µg/L for As. The desorption efficiencies with 2M of KOH after the treatment of groundwater were in the range of 80-83%. A combination of techniques was used to measure the pH, conductivity, cations and anions. The average concentrations of other inorganic constituents of health concern (Na, K, Ca, Mg and Fe in treated water were below their respective WHO guideline for drinking. The present study might provide new avenues to achieve the arsenic concentrations required for drinking water recommended by Bangladesh and the World Health Organization (WHO.

Removal of Arsenic from Drinking Water by Adsorption and Coagulation

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Zhang, M.; Sugita, H.; Hara, J.; Takahashi, S.

2013-12-01

Removal of arsenic from drinking water has been an important issue worldwide, which has attracted greater attentions in recent years especially for supplying safe drinking water in developing countries. Although many kinds of treatment approaches that are available or applicable both in principle and practice, such as adsorption, coagulation, membrane filtration, ion exchange, biological process, electrocoagulation and so on, the first 2 approaches (i.e., adsorption and coagulation) are most promising due to the low-cost, high-efficiency, simplicity of treating systems, and thus can be practically used in developing countries. In this study, a literature survey on water quality in Bangladesh was performed to understand the ranges of arsenic concentration and pH of groundwater in Bangladesh. A series of tests were then organized and performed to investigate the effects of arsenic concentration, arsenic forms, pH, chemical compositions of the materials used for adsorption and coagulation, particle size distribution and treatment time on quality of treated water. The experimental results obtained in the study illustrated that both adsorption and coagulation can be used to effectively reduce the concentrations of either arsenic (V) or arsenic (III) from the contaminated water. Coagulation of arsenic with a magnesium-based material developed in this study can be very effective to remove arsenic, especially arsenic (V), from contaminated water with a concentration of 10 ppm to an undetectable level of 0.002 ppm by ICP analyses. Compared to arsenic (III), arsenic (V) is easier to be removed. The materials used for adsorption and coagulation in this study can remove arsenic (V) up to 9 mg/g and 6 mg/g, and arsenic (III) up to 4 mg/g and 3 mg/g, respectively, depending on test conditions and compositions of the materials being used. The control of pH during treatment can be a challenging technical issue for developing both adsorbent and coagulant. Keywords: Water Treatment

Total and inorganic arsenic in fish samples from Norwegian waters.

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Julshamn, Kaare; Nilsen, Bente M; Frantzen, Sylvia; Valdersnes, Stig; Maage, Amund; Nedreaas, Kjell; Sloth, Jens J

2012-01-01

The contents of total arsenic and inorganic arsenic were determined in fillet samples of Northeast Artic cod, herring, mackerel, Greenland halibut, tusk, saithe and Atlantic halibut. In total, 923 individual fish samples were analysed. The fish were mostly caught in the open sea off the coast of Norway, from 40 positions. The determination of total arsenic was carried out by inductively coupled plasma mass spectrometry following microwave-assisted wet digestion. The determination of inorganic arsenic was carried out by high-performance liquid chromatography-ICP-MS following microwave-assisted dissolution of the samples. The concentrations found for total arsenic varied greatly between fish species, and ranged from 0.3 to 110 mg kg(-1) wet weight. For inorganic arsenic, the concentrations found were very low (fish used in the recent EFSA opinion on arsenic in food.

Arsenic evolution in fractured bedrock wells in central Maine, USA

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Yang, Q.; Zheng, Y.; Culbertson, C.; Schalk, C.; Nielsen, M. G.; Marvinney, R.

2010-12-01

Elevated arsenic concentration in fractured bedrock wells has emerged as an important and challenging health problem, especially in rural areas without public water supply and mandatory monitoring of private wells. This has posed risks of skin, bladder, prostate diseases and cancers to private well users. In central Maine, including the study site, 31% of bedrock wells in meta-sedimentary formations have been reported of elevated arsenic concentrations of > 10 µg/L. Geophysical logging and fracture specific water sampling in high arsenic wells have been conducted to understand how water flowing through the aquifers enters the boreholes and how arsenic evolves in the fracture bedrock wells. Two domestic wells in Manchester, Maine, located 50 meter apart with 38 µg/L and 73 µg/L of arsenic in unfiltered water, were investigated to characterize fractures by geophysical logging and to determine flow rates by pumping test. Water samples, representing the bore hole and the fractures, were collected and analyzed for arsenic under ambient and pumping conditions. Transmissivity of the fractures was estimated at 0.23-10.6 m2/day. Water with high dissolved arsenic was supplied primarily by high yielding fractures near the bottom of the borehole. Dissolved arsenic concentrations in borehole water increased as fracture water with high arsenic was replacing borehole water with initially low dissolved arsenic in response to pumping. The precipitation of iron particulates enriched in arsenic was common during and after pumping. Laboratory experiment on well water samples over a period of 16 days suggested that in the borehole arsenic was mainly settled with iron enriched particles, likely amorphous ferric oxyhydroxides, with possibly minor adsorption on the iron minerals. Another bedrock well in Litchfield, Maine, with 478 µg/L of arsenic in the unfiltered well water, is being investigated to quantify and reconstruct of the groundwater flow under ambient and pumping conditions

Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

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Jasrotia, Shivakshi; Kansal, Arun; Mehra, Aradhana

2017-05-01

This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth ( Eichhornia crassipes) and two algae ( Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3-8.4, whereas COD reduced by 50-65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to arsenic by 40-50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation.

Dissolved Air Flotation of arsenic adsorbent particles

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Mario Enrique Santander Muñoz

2015-01-01

Full Text Available The removal of arsenic from synthetic effluent was studied using the adsorbent particle flotation technique (APF and dissolved air flotation (DAF. A sample of an iron mineral was used as adsorbent particles of arsenic, ferric chloride as coagulant, cationic poly-acrylamide (NALCO 9808 as flocculants, and sodium oleate as collector. Adsorption studies to determine the pH influence, contact time, and adsorbent particles concentration on the adsorption of arsenic were carried out along with flotation studies to determine the removal efficiency of adsorbents particles. The results achieved indicate that the adsorption kinetic of arsenic is very rapid and that in range of pH’s from 2 to 7 the adsorption percentages remain constant. The equilibrium conditions were achieved in 60 minutes and about 95% of arsenic was adsorbed when used an adsorbent concentration of 2 g/L and pH 6.3. The maximum adsorption capacity of adsorbent particles was 4.96 mg/g. The mean free energy of adsorption (E was found to be 2.63 kJ/mol, which suggests physisorption. The results of the flotation studies demonstrated that when synthetic effluents with 8.9 mg/L of arsenic were treated under the following experimental conditions; 2 g/L of adsorbent particles, 120 mg/L of Fe(III, 2 mg/L of Nalco 9808, 20 mg/L of sodium oleate, and 40% of recycle ratio in the DAF, it was possible to reach 98% of arsenic removal and 6.3 NTU of residual turbidity in clarified synthetic effluent.

Arsenic removal by electrocoagulation process: Recent trends and removal mechanism.

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Nidheesh, P V; Singh, T S Anantha

2017-08-01

Arsenic contamination in drinking water is a major issue in the present world. Arsenicosis is the disease caused by the regular consumption of arsenic contaminated water, even at a lesser contaminated level. The number of arsenicosis patients is increasing day-by-day. Decontamination of arsenic from the water medium is the only one way to regulate this and the arsenic removal can be fulfilled by water treatment methods based on separation techniques. Electrocoagulation (EC) process is a promising technology for the effective removal of arsenic from aqueous solution. The present review article analyzes the performance of the EC process for arsenic removal. Electrocoagulation using various sacrificial metal anodes such as aluminium, iron, magnesium, etc. is found to be very effective for arsenic decontamination. The performances of each anode are described in detail. A special focus has been made on the mechanism behind the arsenite and arsenate removal by EC process. Main trends in the disposal methods of sludge containing arsenic are also included. Comparison of arsenic decontamination efficiencies of chemical coagulation and EC is also reported. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of inorganic arsenic in algae using bromine halogenation and on-line nonpolar solid phase extraction followed by hydride generation atomic flourescence spectrometry

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Accurate, stable and fast analysis of toxic inorganic arsenic (iAs) in complicated and arsenosugar-rich algae matrix is always a challenge. Herein, a novel analytical method for iAs in algae was reported, using bromine halogenation and on-line nonpolar solid phase extraction (SPE) followed by hydrid...

Determining the arsenic, cadmium, lead, copper and chromium contents by atomic absorption spectrometry in Pangasius fillets from Vietnam.

Science.gov (United States)

Molognoni, Luciano; Vitali, Luciano; Ploêncio, Leandro As; Santos, Jacson N; Daguer, Heitor

2016-07-01

Pangasius is a fish produced on a large scale in Vietnam and exported to many countries. Since river contamination from human activities can affect the safety of this food, fish consumption can cause exposure to potentially toxic elements for humans. The aim of this study, therefore, was to assess arsenic, cadmium, lead, copper and chromium contents by atomic absorption spectrometry in Pangasius fillet produced in the provinces of Dong Thap and Can Tho (Vietnam) and exported to Brazil. The limits of detection were: arsenic 0.5443 µg kg(-1) , cadmium 0.0040 mg kg(-1) , chromium 0.0004 mg kg(-1) , copper 0.0037 mg kg(-1) and lead 0.0284 mg kg(-1) . Analysis of 20 samples showed results below the limit of detection for arsenic, chromium and lead, while copper average concentration was 0.0234 mg kg(-1) . Cadmium average concentration was 0.0547 mg kg(-1) , with no significant difference between the two regions studied. The samples of Pangasius had no detectable concentrations of arsenic, chromium, copper and lead, and do not represent a hazard to public health. However, cadmium analysis revealed non-compliant samples, demonstrating the importance of monitoring the quality of imported Pangasius fish. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Arsenic contamination in food chain: Thread to food security

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Shekhar Azad Kashyap, Chandra; Singh, Swati

2017-04-01

The supply of good quality food is a necessity for economic and social health welfare of urban and rural population. Over the last several decades groundwater contamination in developing countries has assumed dangerous levels as a result millions of people are at risk. This is so particularly with respect to arsenic that has registered high concentration in groundwater in countries like India and Bangladesh. The arsenic content in groundwater varies from 10 to 780 µg/L, which is far above the levels for drinking water standards prescribed by World Health Organization (WHO). Currently arsenic has entered in food chain due to irrigation with arsenic contaminated water. In the present study reports the arsenic contamination in groundwater that is being used for irrigating paddy in Manipur and West Bengal. The arsenic content in irrigation water is 475 µg/L and 780 µg/L in Manipur and West Bengal, respectively. In order to assess the effect of such waters on the rice crop, we collected rice plant from Manipur and determined the arsenic content in roots, stem, and grain. The arsenic content in grain varies from 110 to 190 mg/kg while the limit of arsenic intake by humans is 10 mg/kg (WHO). This problem is not confine to the area, it spread global level, and rice being cultivated in these regions is export to the other countries like USA, Middle East and Europe and will be thread to global food security.

Costs of Arsenic Removal Technologies for Small Water Systems: U.S. EPA Arsenic Removal Technology Demonstration Program

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As part of the Arsenic Rule Implementation Research Program, between July 2003 and July 2011, the U.S. environmental Protection Agency (EPA) conducted 50 full-scale demonstration projects on treatment systems removing arsenic from drinking water in 26 states throughout the U.S. ...

Spatial modeling for groundwater arsenic levels in North Carolina.

Science.gov (United States)

Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E

2011-06-01

To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area.

Arsenic and Environmental Health: State of the Science and ...

Science.gov (United States)

Background: Exposure to inorganic and organic arsenic compounds is a major public health problem that affects hundreds of millions of people worldwide. Exposure to arsenic is associated with cancer and noncancer effects in nearly every organ in the body, and evidence is mounting for health effects at lower levels of arsenic exposure than previously thought. Building from a tremendous knowledge base with > 1,000 scientific papers published annually with “arsenic” in the title, the question becomes, what questions would best drive future research directions? Objectives: The objective is to discuss emerging issues in arsenic research and identify data gaps across disciplines. Methods: The National Institutes of Health’s National Institute of Environmental Health Sciences Superfund Research Program convened a workshop to identify emerging issues and research needs to address the multi-faceted challenges related to arsenic and environmental health. This review summarizes information captured during the workshop. Discussion: More information about aggregate exposure to arsenic is needed, including the amount and forms of arsenic found in foods. New strategies for mitigating arsenic exposures and related health effects range from engineered filtering systems to phytogenetics and nutritional interventions. Furthermore, integration of omics data with mechanistic and epidemiological data is a key step toward the goal of linking biomarkers of exposure and suscepti

Spatial Modeling for Groundwater Arsenic Levels in North Carolina

Science.gov (United States)

Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E.

2013-01-01

To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. PMID:21528844

Spatial modeling for groundwater arsenic levels in North Carolina

Science.gov (United States)

Kim, D.; Miranda, M.L.; Tootoo, J.; Bradley, P.; Gelfand, A.E.

2011-01-01

To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. ?? 2011 American Chemical Society.

Biotechnology based processes for arsenic removal