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Arsenic Compounds (arsenic + compound)
Selected AbstractsAccumulation of arsenic by Traustochytrium sp.APPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2002CHN-1 from Seto Inland Sea Abstract The accumulation of arsenic by Traustochytrium sp. CHN-1 (Labyrinthulids) was examined by using a medium [2% (w/v) glucose, 0.1% (w/v) yeast extract, 0.1% (w/v) peptone in a half salt concentration of sea water] containing arsenic as As(V), As(III). Traustochytrium sp. CHN-1 was grown in 1/2 sea water medium [2% (w/v) glucose, 0.1% (w/v) yeast extract, 0.1% (w/v) peptone] containing an arsenate (As(V)) at up to 1000,mg dm,3 and arsenite (As(III)) at up to 50,mg dm3. The cells died even at [As(III)]-100,mg dm,3. These results suggested that the order of growth inhibition of Traustochytrium sp. CHN-1 by arsenic was As(III),>,As(V). The biomass of Traustochytrium sp. CHN-1 decreased with an increase of the surrounding arsenic concentration. On the other hand, the arsenic concentration in cells increased with an increase of the surrounding arsenic concentration. Arsenic compounds were extracted with methanol/water (1:1) from a freeze-dried sample of Traustochytrium sp. CHN-1. The extracts were analyzed by high-performance liquid chromatography, with an inductively coupled plasma mass spectrometer serving as an arsenic-specific detector. Arsenite, arsenate, monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA) and arsenosugar were identified in Traustochytrium sp. CHN-1. The order of arsenic species in Traustochytrium sp. CHN-1 was As(V),>,DMAA,>,As(III),>,MMAA,>,arsenosugar at [As]-10,mg dm,3 in the medium. Detoxification of arsenic by cells was probably achieved by methylation. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enteric bacteria may play a role in mammalian arsenic metabolismAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2001Koichi Kuroda Abstract The cecal content of rats administered dimethylarsinic acid for 6 months via drinking water was cultured in GAM medium with 10,mg l,1 of dimethylarsinic acid. Arsenic compounds in the culture were analyzed by ion chromatography with inductively coupled plasma mass spectrometry (IC,ICP-MS). Dimethylarsinic acid was metabolized. Two bacterial Escherichia coli strains, A3-4 and A3-6, were isolated from the culture. These strains metabolized dimethylarsinic acid and yielded two unidentified arsenic compounds, M-2 and M-3. A3-6 methylated dimethylarsinic acid to trimethylarsine oxide. Both strains metabolized trimethylarsine oxide and yielded an unidentified arsenic compound, M-1. These unknown arsenic compounds were the same compounds as detected in the urine and the feces of rats administered dimethylarsinic acid. The strains reduced arsenate to arsenite efficiently. Cysteine was required for metabolism of dimethylarsinic acid by these bacteria, but glutathione was not required. These results strongly suggested that the intestinal bacteria have a different arsenic metabolism from that in mammals and that they may play a possible role in mammalian arsenic metabolism. Copyright © 2001 John Wiley & Sons, Ltd. [source] Arsenic speciation in terrestrial birds from Yellowknife, Northwest Territories, Canada: The unexpected finding of arsenobetaineENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2005Iris Koch Abstract The surrounding area of Yellowknife, Northwest Territories, Canada, is known for naturally and anthropogenically elevated concentrations of arsenic. Five bird species (gray jay [Perisoreus canadensis], American tree sparrow [Spizella arborea], dark-eyed junco [Junco hyemalis], yellow-rumped warbler [Dendroica coronata], and spruce grouse [Dendragapus canadensis]) were collected from this area. Their tissues were analyzed for total arsenic and for arsenic species, allowing us to report, to our knowledge for the first time, the arsenic characterization in terrestrial birds. Total arsenic concentrations were determined in the terrestrial birds by inductively coupled plasma-optical emission spectrometry, whereas arsenic speciation analysis was performed using high-performance liquid chromatography-inductively coupled plasma-mass spectrometry. Total arsenic concentrations were substantially higher in the terrestrial bird species studied from Yellowknife compared with those reported previously in the literature. The primary arsenic species detected in two of the bird species studied was arsenobetaine. Normally, arsenobetaine is not formed or retained by terrestrial animals. Thus, the birds in the present study were thought to be highly adapted compared with other terrestrial animals, because they were able to form and/or retain this relatively nontoxic arsenic compound. This adaptation is thought to be a consequence of the elevated concentrations of arsenic in the Yellowknife area. [source] Occurrence of several arsenic compounds in the liver of birds, cetaceans, pinnipeds, and sea turtlesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2003Reiji Kubota Abstract Concentrations of total arsenic and individual arsenic compounds were determined in livers of birds, cetaceans, pinnipeds, and sea turtles by using hydride generation-atomic absorption spectrometry and high-performance liquid chromatography/inductively coupled plasma-mass spectrometry. Hepatic arsenic concentrations in loggerhead turtles (11.2 ± 3.0 ,g/g dry wt) and black-footed albatrosses (12.2 ± 10.8 ,g/g dry wt) were extremely high among the species examined, and the values were comparable with those of lower trophic marine animals such as fishes, cephalopods, crustaceans, and shellfishes. In all the species, arsenobetaine was the predominant arsenic compound in the livers. Especially, for black-footed albatrosses and black-tailed gull, the mean percentage of arsenobetaine was as high as 97.1 and 87.5, respectively, of extractable arsenic. The present study is among the first on arsenic speciation in avian species. Total arsenic concentration was strongly correlated with the concentration of arsenobetaine, while no significant relationship was observed between total arsenic concentration and other arsenic compounds in these animals. Because arsenobetaine is known to be rapidly excreted into the urine in humans and experimental animals, the observed results suggest that higher trophic marine animals might have a unique metabolism of arsenobetaine and that arsenobetaine plays an important role in the accumulation of arsenic in these animals. [source] Effects of arsenobetaine, a major organic arsenic compound in seafood, on the maturation and functions of human peripheral blood monocytes, macrophages and dendritic cellsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2004Takami Ohta Abstract We examine the in vitro immunotoxicity of synthetically pure arsenobetaine [AsBe; trimethyl (carboxymethyl) arsonium zwitterion], which is a major organic arsenic compound in seafood, on various human immune cells, such as peripheral blood monocytes, monocyte-derived macrophages and monocyte-derived dendritic cells (DCs). In particular, we examine the differentiation of monocytes into macrophages or DCs by comparing the effects of AsBe with those pentavalent inorganic arsenate. AsBe neither enhanced nor inhibited the differentiation of human monocytes into macrophages or DCs, and also did not affect their various immune functions. Furthermore, AsBe had no cytolethality in monocyte-derived macrophages or DCs even at a concentration of 5 mmol l,1. In contrast, inorganic arsenate showed strong cytolethality in these human immune cells in vitro at micromolar concentrations. These data indicate that the organic arsenic compound AsBe in seafood has no in vitro immunotoxicity in human immune cells. Copyright © 2004 John Wiley & Sons, Ltd. [source] Review: Biological effects of organic arsenic compounds in seafood,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2002Teruaki Sakurai Abstract This review describes the results of our recent experiments concerning the in vitro biological effects of water-soluble organic arsenic compounds contained in seafood in murine immune effector cells using synthetic pure materials. A dimethyl organic arsenic compound in seaweed, viz. an arsenosugar, was weakly cytotoxic in murine alveolar macrophages during a 72,h incubation (50% lethal concentration in vitro, LC50,=,8,mmol,dm,3); conversely, it increased the cell viability of peritoneal macrophages at an optimal dose of 5,mmol,dm,3. Trimethyl arsenic compounds in marine animals, arsenocholine and arsenobetaine, were less toxic in murine splenocytes, thymocytes, Peyer's patch lymphocytes, peritoneal macrophages and alveolar macrophages in vitro, even over 10,mmol,dm,3. Interestingly, they significantly increased the cell viability of immature bone marrow cells at doses over 100,µmol dm,3, and induced the maturation of bone marrow cells especially into granulocytes. The tetramethyl arsenic compound, tetramethylarsonium hydroxide, isolated from some lower marine animals had no in vitro cytolethality on murine immune effector cells. Taken together, organic arsenic compounds in seafood are not very toxic in living systems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enteric bacteria may play a role in mammalian arsenic metabolismAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2001Koichi Kuroda Abstract The cecal content of rats administered dimethylarsinic acid for 6 months via drinking water was cultured in GAM medium with 10,mg l,1 of dimethylarsinic acid. Arsenic compounds in the culture were analyzed by ion chromatography with inductively coupled plasma mass spectrometry (IC,ICP-MS). Dimethylarsinic acid was metabolized. Two bacterial Escherichia coli strains, A3-4 and A3-6, were isolated from the culture. These strains metabolized dimethylarsinic acid and yielded two unidentified arsenic compounds, M-2 and M-3. A3-6 methylated dimethylarsinic acid to trimethylarsine oxide. Both strains metabolized trimethylarsine oxide and yielded an unidentified arsenic compound, M-1. These unknown arsenic compounds were the same compounds as detected in the urine and the feces of rats administered dimethylarsinic acid. The strains reduced arsenate to arsenite efficiently. Cysteine was required for metabolism of dimethylarsinic acid by these bacteria, but glutathione was not required. These results strongly suggested that the intestinal bacteria have a different arsenic metabolism from that in mammals and that they may play a possible role in mammalian arsenic metabolism. Copyright © 2001 John Wiley & Sons, Ltd. [source] Toxicity of a trivalent organic arsenic compound, dimethylarsinous glutathione in a rat liver cell line (TRL 1215)BRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2006T Sakurai Background and purpose: Although inorganic arsenite (AsIII) is toxic in humans, it has recently emerged as an effective chemotherapeutic agent for acute promyelocytic leukemia (APL). In humans and most animals, AsIII is enzymatically methylated in the liver to weakly toxic dimethylarsinic acid (DMAsV) that is a major pentavalent methylarsenic metabolite. Recent reports have indicated that trivalent methylarsenicals are produced through methylation of AsIII and participate in arsenic poisoning. Trivalent methylarsenicals may be generated as arsenical,glutathione conjugates, such as dimethylarsinous glutathione (DMAsIIIG), during the methylation process. However, less information is available on the cytotoxicity of DMAsIIIG. Experimental approach: We synthesized and purified DMAsIIIG using high performance TLC (HPTLC) methods and measured its cytotoxicity in rat liver cell line (TRL 1215 cells). Key results: DMAsIIIG was highly cytotoxic in TRL 1215 cells with a LC50 of 160 nM. We also found that DMAsIIIG molecule itself was not transported efficiently into the cells and was not cytotoxic; however it readily became strongly cytotoxic by dissociating into trivalent dimethylarsenicals and glutathione (GSH). The addition of GSH in micromolar physiological concentrations prevented the breakdown of DMAsIIIG, and the DMAsIIIG-induced cytotoxicity. Physiological concentrations of normal human serum (HS), human serum albumin (HSA), and human red blood cells (HRBC) also reduced both the cytotoxicity and cellular arsenic uptake induced by exposure to DMAsIIIG. Conclusions and implications: These findings suggest that the significant cytotoxicity induced by DMAsIIIG may not be seen in healthy humans, even if DMAsIIIG is formed in the body from AsIII. British Journal of Pharmacology (2006) 149, 888,897. doi:10.1038/sj.bjp.0706899 [source] Modulation of cell adhesion and viability of cultured murine bone marrow cells by arsenobetaine, a major organic arsenic compound in marine animalsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2001Teruaki Sakurai In this study, we investigated the biological effects of trimethyl (carboxymethyl) arsonium zwitterion, namely arsenobetaine (AsBe), which is a major organic arsenic compound in marine animals using murine bone marrow (BM) cells and compared them with those of an inorganic arsenical, sodium arsenite, in vitro. Sodium arsenite showed strong cytotoxicity in BM cells, and its IC50 was 6 ,M. In contrast, AsBe significantly enhanced the viability of BM cells in a dose-dependent manner during a 72-h incubation; about a twofold increase in the viability of cells compared with that of control cells cultured with the medium alone was observed with a ,M level of AsBe. In morphological investigations, AsBe enhanced the numbers of large mature adherent cells, especially granulocytes, during a 72-h BM culture. When BM cells were cultured together with AsBe and a low dose (1 u ml,1) of recombinant murine granulocyte/macrophage colony-stimulating factor (rMu GM-CSF), significant additive-like increasing effects were observed on the numbers of both granulocytes and macrophages originated from BM cells. However, AsBe did not cause proliferation of BM cells at all as determined by colony-forming assay using a gelatious medium. These findings demonstrate the unique and potent biological effects in mammalian cells of AsBe, a major organic arsenic compound in various marine animals which are ingested daily as seafood in many countries. British Journal of Pharmacology (2001) 132, 143,150; doi:10.1038/sj.bjp.0703790 [source] Speciation of arsenic compounds in fish and oyster tissues by capillary electrophoresis-inductively coupled plasma-mass spectrometryELECTROPHORESIS, Issue 7-8 2005Ching-Fen Yeh Abstract A capillary electrophoresis-inductively coupled plasma-mass spectrometric (CE-ICP-MS) method for the speciation of six arsenic compounds, namely arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid, dimethylarsinic acid, arsenobetaine and arsenocholine is described. The separation has been achieved on a 70,cm length×75,µm,ID fused-silica capillary. The electrophoretic buffer used was 15,mM Tris (pH,9.0) containing 15,mM sodium dodecyl sulfate (SDS), while the applied voltage was set at +22,kV. The arsenic species in biological tissues were extracted into 80%,v/v methanol-water mixture, put in a closed centrifuge tube and kept in a water bath, using microwaves at 80°C for 3,min. The extraction efficiencies of individual arsenic species added to the sample at 0.5,µg As/g level were between 96% and 107%, except for As(III), for which it was 89% and 77% for oyster and fish samples, respectively. The detection limits of the species studied were in the range 0.3,0.5,ng As/mL. The procedure has been applied for the speciation analysis of two reference materials, namely dogfish muscle tissue (NRCC DORM-2) and oyster tissue (NIST SRM 1566a), and two real-world samples. [source] On-line preconcentration for capillary electrophoresis-atomic fluorescence spectrometric determination of arsenic compoundsELECTROPHORESIS, Issue 12 2004Xue-Bo Yin Abstract An on-line preconcentration method was developed for capillary electrophoresis (CE) with hydride generation-atomic fluorescence spectrometric (HG-AFS) detection of arsenite, arsenate, dimethylarsenic acid, and monomethylarsenic acid. These arsenic species were negatively charged in the sample solution with high pH. When the potential was applied to the electrophoretic capillary, the negatively charged analyte ions moved faster and stacked at the boundary of sample and CE buffer with low pH. So, high sample pH in combination with low buffer pH allowed the injection of large sample volumes (, 1100 nL). Comparison of the preconcentration of analyte solution, prepared with doubly deionized water and that prepared with lake or river water, indicated that preconcentration was independent on the original matrix. With injection of ,1100 nL sample, an enrichment factor of 37,50-fold was achieved for the four species. Detection limits for the four arsenic species ranged from 5.0 to 9.3 ,g·L,1. Precisions (RSDs, n = 5) were in the range of 4.9,6.7% for migration time, 4.7,11% for peak area, and 4.3,7.1% for peak height, respectively. The recoveries of the four species in locally collected water solution spiked with 0.1 ,g·mL,1 (as As) ranged from 83 to 109%. [source] Analysis of genomic dose-response information on arsenic to inform key events in a mode of action for carcinogenicityENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2010P. Robinan Gentry Abstract A comprehensive literature search was conducted to identify information on gene expression changes following exposures to inorganic arsenic compounds. This information was organized by compound, exposure, dose/concentration, species, tissue, and cell type. A concentration-related hierarchy of responses was observed, beginning with changes in gene/protein expression associated with adaptive responses (e.g., preinflammatory responses, delay of apoptosis). Between 0.1 and 10 ,M, additional gene/protein expression changes related to oxidative stress, proteotoxicity, inflammation, and proliferative signaling occur along with those related to DNA repair, cell cycle G2/M checkpoint control, and induction of apoptosis. At higher concentrations (10,100 ,M), changes in apoptotic genes dominate. Comparisons of primary cell results with those obtained from immortalized or tumor-derived cell lines were also evaluated to determine the extent to which similar responses are observed across cell lines. Although immortalized cells appear to respond similarly to primary cells, caution must be exercised in using gene expression data from tumor-derived cell lines, where inactivation or overexpression of key genes (e.g., p53, Bcl-2) may lead to altered genomic responses. Data from acute in vivo exposures are of limited value for evaluating the dose-response for gene expression, because of the transient, variable, and uncertain nature of tissue exposure in these studies. The available in vitro gene expression data, together with information on the metabolism and protein binding of arsenic compounds, provide evidence of a mode of action for inorganic arsenic carcinogenicity involving interactions with critical proteins, such as those involved in DNA repair, overlaid against a background of chemical stress, including proteotoxicity and depletion of nonprotein sulfhydryls. The inhibition of DNA repair under conditions of toxicity and proliferative pressure may compromise the ability of cells to maintain the integrity of their DNA. Environ. Mol. Mutagen., 2010. © 2009 Wiley-Liss, Inc. [source] Occurrence of several arsenic compounds in the liver of birds, cetaceans, pinnipeds, and sea turtlesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2003Reiji Kubota Abstract Concentrations of total arsenic and individual arsenic compounds were determined in livers of birds, cetaceans, pinnipeds, and sea turtles by using hydride generation-atomic absorption spectrometry and high-performance liquid chromatography/inductively coupled plasma-mass spectrometry. Hepatic arsenic concentrations in loggerhead turtles (11.2 ± 3.0 ,g/g dry wt) and black-footed albatrosses (12.2 ± 10.8 ,g/g dry wt) were extremely high among the species examined, and the values were comparable with those of lower trophic marine animals such as fishes, cephalopods, crustaceans, and shellfishes. In all the species, arsenobetaine was the predominant arsenic compound in the livers. Especially, for black-footed albatrosses and black-tailed gull, the mean percentage of arsenobetaine was as high as 97.1 and 87.5, respectively, of extractable arsenic. The present study is among the first on arsenic speciation in avian species. Total arsenic concentration was strongly correlated with the concentration of arsenobetaine, while no significant relationship was observed between total arsenic concentration and other arsenic compounds in these animals. Because arsenobetaine is known to be rapidly excreted into the urine in humans and experimental animals, the observed results suggest that higher trophic marine animals might have a unique metabolism of arsenobetaine and that arsenobetaine plays an important role in the accumulation of arsenic in these animals. [source] Arsenic derivatives in hematologic malignancies: a role beyond acute promyelocytic leukemia?HEMATOLOGICAL ONCOLOGY, Issue 4 2006Srdan Verstovsek Abstract The importance of arsenic trioxide (As2O3) has been underscored over the last decade due to its efficacy against acute promyelocytic leukemia (APL), a disease in which this agent has been associated with complete hematologic and molecular remission rates of 87% and 83%, respectively. The different molecular mechanisms of action of As2O3 suggest its applicability in hematologic malignancies other than APL. However, responses obtained thus far have consisted of improvements in signs and symptoms without the elimination of a given disease. Toxicities derived from As2O3 are significant but manageable and reversible. However, the risk/benefit ratio of As2O3 in hematologic malignancies other than APL is still unclear. The development of new generations of orally bioavailable inorganic, as well as new organic, arsenic compounds with improved toxicity profiles may bolster the therapeutic application of arsenic derivatives in hematologic malignancies such as leukemia, multiple myeloma and myelodysplastic syndromes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Development of resistance to biocides used in vinylJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2007Richard F. Grossman The opportunistic bacterium Pseudomonas fluorescens and the predatory fungus Trichoderma viride can develop heritable resistance to the common broad spectrum biocide Captan. Another biocide commonly used in vinyl compositions to replace organic arsenic compounds, zinc pyrithione, appears more difficult to mutate against. J. VINYL ADDIT. TECHNOL., 13:136,137, 2007. © 2007 Society of Plastics Engineers [source] Levels and chemical speciation of arsenic in polychaetes: a reviewMARINE ECOLOGY, Issue 3-4 2005Daniele Fattorini Abstract Relatively few studies have characterized basal content and variability of arsenic in polychaetes, despite the potential importance of this element as a pollutant of marine environments. Even less have investigated the chemical speciation of arsenic, occurring as inorganic and organic forms, which reflect a different biological reactivity of the element. In the present paper we integrate existing literature with new data in order to summarize the status quo on arsenic bioaccumulation in polychaetes. We consider species with different trophic habits, phylogenetic relationships, geographic distribution and ecology. Reported data indicate a high variability in arsenic concentration with levels ranging from <1 ,g·g,1 to more than 2500 ,g·g,1 in different species; some additional species analyzed in this work confirm species-specific characteristics which are not easily explained by biological or ecological factors. The profile of arsenic compounds in polychaetes is different to that of most aquatic organisms. Typically this element occurs in non-toxic organic forms, however several polychaete species have been shown to accumulate relatively toxic molecules and subsequently biotransform them by processes such as methylation. Conclusions from the literature review reveal a complex array of arsenic actions in the environment and suggest a biological role of this element in the life history of some polychaete species. [source] Occupational risk factors for non-Hodgkin's lymphoma: A population-based case,control study in Northern GermanyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2008David B. Richardson Abstract Objectives To identify occupational factors associated with non-Hodgkin's lymphoma (NHL). Methods A population-based case,control study was conducted in which incident cases of high-malignancy NHL (NHLhigh), low-malignancy NHL (NHLlow), and chronic lymphocytic leukemia (CLL) were ascertained during the period 1986,1998 among men and women aged 15,75 years residing in six German counties; controls were drawn from population registries. Occupational histories were collected and agent-specific exposures were estimated via a job-exposure-matrix. Odds ratios were estimated by conditional logistic regression. Results A total of 858 cases were included in these analyses. Agricultural workers [odds ratio (OR),=,2.67, 95% confidence interval (CI): 0.99, 7.21) and farmers (OR,=,1.98, 95% CI: 0.98, 3.98] had elevated risk of NHLhigh. Risk of NHLlow was elevated among agricultural workers (OR,=,2.46, 95% CI: 1.17, 5.16), and among blacksmiths, toolmakers, and machine tool operators (OR,=,3.12, 95% CI: 1.31, 7.47). Workers in sales and construction had elevated risks of NHLhigh and NHLlow. Exposure to arsenic compounds, chlorophenols, diesel fuel, herbicides, nitrites/nitrates/nitrosamines, and organic dusts were associated with NHLhigh and NHLlow, while exhibiting little association with CLL. A positive monotonic trend in NHLlow risk across tertiles of cumulative diesel fuel exposure was observed [P -value for test of linear trend (P),=,0.03]. Conclusions These findings provide insights into several potential occupational risk factors for NHL and suggest some specific occupational agents for further investigation. Am. J. Ind. Med. 51:258,268, 2008. © 2008 Wiley-Liss, Inc. [source] Nitrogen purity influences the occurrence of As+ ions in high-performance liquid chromatography/electrospray ionization mass spectrometric analysis of four common arsenosugarsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 7 2003Doris Kuehnelt High-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC/ESI-MS) can provide both elemental and molecular information and, therefore, is a very useful tool for the identification of arsenic compounds. When a method for the identification of four arsenosugars was employed in our laboratory with an HPLC/ESI-MS system equipped with a Whatman model 75-72 nitrogen generator, a signal at m/z 75 (As+) could not be observed. When the HPLC/ESI-MS system was operated with nitrogen 5.0 (nitrogen of a purity of at least 99.999%) all four arsenosugars gave a signal at m/z 75. Because of this observation the influence of the quality of the nitrogen drying gas on the fragmentation of the four arsenosugars was systematically investigated. Standard solutions containing the four arsenosugars (0.5 ng As each) were separated on an anion-exchange column and detected with ESI-MS in the positive ion mode by monitoring the signals for [M+H]+, m/z 237, 91, and 75. Nitrogen with defined oxygen concentrations was used as drying gas. The purity of the nitrogen ranged from 99 to 99.999% (10,400 to 10 ppm oxygen impurity). The nitrogen with 99% purity gave no signal at m/z 75, but signals were obtained at m/z 91, 237, and for [M+H]+. When higher purity nitrogen (99.9%) was used, a signal was obtained at m/z 75, which accounted for 0.8,1.1% (depending on the kind of arsenosugar) of the sum of the signals for m/z 75, 91, 237 and [M+H]+. As the level of oxygen in the nitrogen decreased, the m/z 75 signal increased to 2.0,3.1%. This was accompanied by a concomitant decrease in the m/z 91 signal from 5.2,6.6% to 0.7,1.5%, whereas the signals for [M+H]+ and m/z 237 were essentially unchanged. Signals at m/z 75 with intensities comparable with those observed for the 99.9% pure nitrogen were also obtained for all the arsenosugars when the HPLC/ESI-MS system was operated with a Domnick Hunter Nitrox UHPLCMS18 nitrogen generator. Dimethylarsinic acid, arsenobetaine, trimethylarsine oxide, arsenocholine and the tetramethylarsonium cation also gave no signal at m/z 75 when they were analyzed with the Whatman model 75-72 nitrogen generator, but clear signals at m/z 75 were observed with the Domnick Hunter Nitrox UHPLCMS18 nitrogen generator. A nitrogen quality of at least 99.9% is required to obtain elemental information (m/z 75) when arsenic compounds are investigated by HPLC/ESI-MS. Molecular and elemental information from one chromatographic run is a valuable tool for the characterization of unknown arsenic compounds. Copyright © 2003 John Wiley & Sons, Ltd. [source] Determination of diphenylarsinic acid and phenylarsonic acid, the degradation products of organoarsenic chemical warfare agents, in well water by HPLC,ICP-MSAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 2 2005Kenji Kinoshita Abstract Diphenylarsinic acid (DPAA) and phenylarsonic acid (PAA), which were degradation products of organoarsenic chemical warfare agents used as sternutatory gas, were detected in the well water at Kamisu, Ibaraki Prefecture, Japan. The standard material of DPAA was synthesized with aqueous arsenic acid and phenylhydrazine in order to determine organic arsenic compounds in well water. The DPAA showed a protonated ion at m/z 263 [M + H]+ and a loss of H2O ion at m/z 245 [M + H , H2O]+ from protonated ion by the electrospray ionization time-of-flight mass spectrometry. The quantitative analysis of DPAA and PAA was performed by high-performance liquid chromatography inductively coupled plasma mass spectrometry and the system worked well for limpid liquid samples such as well water. Copyright © 2005 John Wiley & Sons, Ltd. [source] Review: Biological effects of organic arsenic compounds in seafood,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2002Teruaki Sakurai Abstract This review describes the results of our recent experiments concerning the in vitro biological effects of water-soluble organic arsenic compounds contained in seafood in murine immune effector cells using synthetic pure materials. A dimethyl organic arsenic compound in seaweed, viz. an arsenosugar, was weakly cytotoxic in murine alveolar macrophages during a 72,h incubation (50% lethal concentration in vitro, LC50,=,8,mmol,dm,3); conversely, it increased the cell viability of peritoneal macrophages at an optimal dose of 5,mmol,dm,3. Trimethyl arsenic compounds in marine animals, arsenocholine and arsenobetaine, were less toxic in murine splenocytes, thymocytes, Peyer's patch lymphocytes, peritoneal macrophages and alveolar macrophages in vitro, even over 10,mmol,dm,3. Interestingly, they significantly increased the cell viability of immature bone marrow cells at doses over 100,µmol dm,3, and induced the maturation of bone marrow cells especially into granulocytes. The tetramethyl arsenic compound, tetramethylarsonium hydroxide, isolated from some lower marine animals had no in vitro cytolethality on murine immune effector cells. Taken together, organic arsenic compounds in seafood are not very toxic in living systems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Comparison of three methods for the extraction of arsenic compounds from the NRCC standard reference material DORM-2 and the brown alga Hijiki fuziformeAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2001Doris Kuehnelt Abstract The NRCC standard reference material DORM-2 and the marine brown alga Hijiki fuziforme were extracted with water, methanol/water (9,+,1), and 1.5 M orthophosphoric acid. The extracts from DORM-2 were analyzed by HPLC,ICP-MS for arsenobetaine, arsenocholine, trimethylarsine oxide, and the tetramethylarsonium cation and the extracts from H. fuziforme for arsenous acid, arsenic acid, dimethylarsinic acid, methylarsonic acid, and four arsenoriboses. Almost no differences between the three extractants were observed when DORM-2 was investigated. Only arsenobetaine was slightly better extracted with 1.5 M orthophosphoric acid or methanol/water (9,+,1) than with water. The sum of all extractable compounds (arsenobetaine, the tetramethylarsonium cation, and a formerly unknown compound recently identified as the trimethyl(2-carboxyethyl)arsonium ion) accounted for 94% of the total arsenic when 1.5 M orthophosphoric acid was used, for 92% when methanol/water (9,+,1) was used, and for 87% when water was used. Significant differences in the extraction yields obtained for the alga were observed for arsenic acid and one of the arsenoriboses (,glycerol-ribose'). Orthophosphoric acid removed twice as much of this ribose from the algal material than water and three times more than methanol/water (9,+,1). Arsenic acid was 1.2 times better extracted with orthophosphoric acid than with water and ten times better than with methanol/water (9,+,1). Almost no differences in the extraction yields were found for dimethylarsinic acid and the other three riboses. Orthophosphoric acid extracted 76%, water 65%, and methanol/water 33% of the total arsenic from H. fuziforme. Copyright © 2001 John Wiley & Sons, Ltd. [source] Enteric bacteria may play a role in mammalian arsenic metabolismAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2001Koichi Kuroda Abstract The cecal content of rats administered dimethylarsinic acid for 6 months via drinking water was cultured in GAM medium with 10,mg l,1 of dimethylarsinic acid. Arsenic compounds in the culture were analyzed by ion chromatography with inductively coupled plasma mass spectrometry (IC,ICP-MS). Dimethylarsinic acid was metabolized. Two bacterial Escherichia coli strains, A3-4 and A3-6, were isolated from the culture. These strains metabolized dimethylarsinic acid and yielded two unidentified arsenic compounds, M-2 and M-3. A3-6 methylated dimethylarsinic acid to trimethylarsine oxide. Both strains metabolized trimethylarsine oxide and yielded an unidentified arsenic compound, M-1. These unknown arsenic compounds were the same compounds as detected in the urine and the feces of rats administered dimethylarsinic acid. The strains reduced arsenate to arsenite efficiently. Cysteine was required for metabolism of dimethylarsinic acid by these bacteria, but glutathione was not required. These results strongly suggested that the intestinal bacteria have a different arsenic metabolism from that in mammals and that they may play a possible role in mammalian arsenic metabolism. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||||||||