@article {1091,
	title = {The toxicity of trimethylarsine: an urban myth},
	journal = {Journal of Environmental Monitoring},
	volume = {7},
	number = {1},
	year = {2005},
	note = {ISI Document Delivery No.: 896IBTimes Cited: 7Cited Reference Count: 50},
	month = {Jan},
	pages = {11-15},
	type = {News Item},
	keywords = {DISEASE, IN-VITRO, METHYLATION, MICE, STACHYBOTRYS-CHARTARUM},
	isbn = {1464-0325},
	url = {<Go to ISI>://000226926700007},
	author = {Cullen, W. R. and Bentley, R.}
}
@article {663,
	title = {Arsenic methylation by micro-organisms isolated from sheepskin bedding materials},
	journal = {Human \& Experimental Toxicology},
	volume = {22},
	number = {6},
	year = {2003},
	note = {ISI Document Delivery No.: 696NKTimes Cited: 6Cited Reference Count: 48},
	month = {Jun},
	pages = {325-334},
	type = {Article},
	abstract = {Sudden infant death syndrome (SIDS) has been associated with the volatilization of arsenic, antimony or phosphorus compounds from infants{\textquoteright} bedding material by micro-organisms, the so-called {\textquoteright}toxic gas hypothesis{\textquoteright}. The volatilization of arsenic by aerobic micro-organisms isolated from new sheepskin bedding material, as well as on material used by a healthy infant and by an infant who perished of SIDS, was examined. Three fungi were isolated from a piece of sheepskin bedding material on which an infant perished of SIDS, which methylated arsenic to form trimethylarsenic(V) species, precursors to volatile trimethylarsine. These three fungi were identified as Scopulariopsis koningii, Fomitopsis pinicola and Penicillium gladioli by their 26S-ribosomal RNA polymerase chain reaction products. These fungi were not previously known to methylate arsenic. The volatilization of arsenic by these three fungi was then examined. Only R gladioli volatilized arsenic and only under conditions such that the production of sufficient trimethylarsine to be acutely toxic to an infant is unlikely. S. brevicaulis grew on the sheepskin bedding material and evolved a trace amount of trimethylarsine. Known human pathogens such as Mycobacterium neoaurum and Acinetobacter junii were isolated from used bedding.},
	keywords = {ANTIMONY COMPOUNDS, arsenic, BIOMETHYLATION, COT MATTRESSES, fungi, GAS, hypothesis, IDENTIFICATION, INFANT-DEATH-SYNDROME, METHYLATION, SCOPULARIOPSIS-BREVICAULIS, SPECIATION, sudden infant death syndrome, toxic gas, TRIMETHYLARSINE, VOLATILIZATION},
	isbn = {0960-3271},
	url = {<Go to ISI>://000183892800008},
	author = {Lehr, C. R. and Polishchuk, E. and Delisle, M. C. and Franz, C. and Cullen, W. R.}
}
@article {386,
	title = {Determination of arsenic metabolic complex excreted in human urine after administration of sodium 2,3-dimercapto-1-propane sulfonate},
	journal = {Chemical Research in Toxicology},
	volume = {15},
	number = {10},
	year = {2002},
	note = {ISI Document Delivery No.: 607TXTimes Cited: 15Cited Reference Count: 42},
	month = {Oct},
	pages = {1318-1323},
	type = {Article},
	abstract = {Sodium 2,3-dimercapto-1-propane sulfonate (DMPS) has been used to treat acute arsenic poisoning. Presumably DMPS functions by chelating some arsenic species to increase the excretion of arsenic from the body. However, the excreted complex of DMPS with arsenic has not been detected. Here we describe a DMPS complex with monomethylarsonous acid (MMA(III)), a key trivalent arsenic in the arsenic methylation process, and show the presence of the DMPS-MMA(III) complex in human urine after the administration of DMPS. The DMPS-MMA(III) complex was characterized using electrospray tandem mass spectrometry and determined by using HPLC separation with hydride generation atomic fluorescence detection (HGAFD). The DMPS-MMAIII complex did not form a volatile hydride with borohydride treatment. On-line digestion with 0.1 M sodium hydroxide following HPLC separation decomposed the DMPS-MMA(III) complex and allowed for the subsequent quantification by hydride generation atomic fluorescence. Arsenite (As-III), arsenate (As-V), monomethylarsonic, acid (MMA(V)), dimethylarsinic acid (DMA(V)), MMA(III), and DMPS-MMA(III) complex were analyzed in urine samples from human subjects collected after the ingestion of 300 mg of DMPS. The administration of DMPS resulted in a decrease of the DMA(V) concentration and an increase of the MMA(V) concentration excreted in the urine, confirming the previous results. The finding of the DMPS-MMA(III) complex in human urine after DMPS treatment provides an explanation for the inhibition of arsenic methylation by DMPS. Because MMA(III) is the substrate for the biomethylation of arsenic from MMA(V) to DMA(V), the formation of DMPS-MMA(III) complex would reduce the availability of MMA(III) for the subsequent biomethylation.},
	keywords = {ARSENICALS, CHALLENGE TEST, DRINKING-WATER, ENZYMATIC, GLUTATHIONE-REDUCTASE, HUMAN HEPATOCYTES, IN-VITRO INHIBITION, LIVER, METHYLATED, METHYLATION, MONOMETHYLARSONOUS ACID MMA(III), RABBIT, THIOREDOXIN REDUCTASE},
	isbn = {0893-228X},
	url = {<Go to ISI>://000178807800016},
	author = {Gong, Z. and Jiang, G. F. and Cullen, W. R. and Aposhian, H. V. and Le, X. C.}
}
@article {553,
	title = {Facile synthesis of N,N {\textquoteright}-dimethylated N-confused porphyrins},
	journal = {Tetrahedron},
	volume = {58},
	number = {44},
	year = {2002},
	note = {ISI Document Delivery No.: 608QCTimes Cited: 4Cited Reference Count: 8},
	month = {Oct},
	pages = {9111-9116},
	type = {Article},
	abstract = {N-Confused tetraarylporphyrins react with CH3I in the presence of Na2CO3 to give, in high yield, N,N{\textquoteright}-dimethylated N-confused porphyrin salts, which are mixtures of structural isomers. The structures of the major isomers were determined by X-ray diffraction and NMR spectroscopic analyses. These N,N{\textquoteright}-dimethylated N-confused tetraarylporphyrin salts generate singlet oxygen when irradiated at long wavelengths in the visible region, and therefore, are potential sensitizers for photodynamic therapy. (C) 2002 Elsevier Science Ltd. All rights reserved.},
	keywords = {ISOMER, METHYLATION, N, N {\textquoteright}-dimethylated N-confused porphyrin, N-confused porphyrin, RING, singlet oxygen, TETRAPHENYLPORPHYRIN},
	isbn = {0040-4020},
	url = {<Go to ISI>://000178857300026},
	author = {Xiao, Z. W. and Dolphin, D.}
}
@article {5045,
	title = {Determination of trivalent methylated arsenicals in biological matrices},
	journal = {Toxicology and Applied Pharmacology},
	volume = {174},
	number = {3},
	year = {2001},
	note = {ISI Document Delivery No.: 464KTTimes Cited: 129Cited Reference Count: 67},
	month = {Aug},
	pages = {282-293},
	type = {Article},
	abstract = {The enzymatically catalyzed oxidative methylation of As yields methylated arsenicals that contain pentavalent As (As-V). Because trivalent As (As-III) is the favored substrate for this methyltransferase, methylated arsenicals containing As-V are reduced to trivalency in cells. Methylated arsenicals that contain As-III are extremely potent inhibitors of NADPH-dependent flavoprotein oxidoreductases and potent cytotoxins in many cell types. Therefore, the formation of methylated arsenicals that contain As-III may be properly regarded as an activation step, rather than a means of detoxification. Recognition of the role of methylated arsenicals that contain As-III in the toxicity and metabolism of As emphasizes the need for analytical methods to detect and quantify these species in biological samples. Hence, a method was developed to exploit pH-dependent differences in the generation of arsines from inorganic and methylated arsenicals that contain either As-V or As-III. Reduction with borohydride at pH 6 generated arsines from inorganic As-III, methyl As-III, and dimethyl As-III, but not from inorganic As-V, methyl As-V, and dimethyl As-V. Reduction with borohydride at pH 2 or lower generated arsines from arsenicals that contained either As-V or As-III. Arsines are trapped in a liquid nitrogen-cooled gas chromatographic trap, which is subsequently warmed to allow separation of the hydrides by their boiling points. Atomic absorption spectrophotometry is used to detect and quantify the arsines. The detection limits (ng As ml(-1)) for inorganic As-III, methyl As-III, and dimethyl As-III are 1.1, 1.2, and 6.5, respectively. This method has been applied to the analysis of arsenicals in water, human urine, and cultured cells. Both methyl As-III. and dimethyl As-III are detected in urine samples from individuals who chronically consumed inorganic As-contaminated water and in human cells exposed in vitro to inorganic As-III. The reliable quantitation of inorganic and methylated arsenicals that contain As-III. in biological samples will aid the study of the toxicity of these species and may provide a new biomarker of the effects of chronic exposure to As. (C) 2001 Academic Press.},
	keywords = {analysis, arsenic, atomic absorption spectrophotometry, biological matrices, CANCER MORTALITY, DIABETES-MELLITUS, DIMETHYLARSINIC ACID, DOSE-RESPONSE RELATIONSHIP, DRINKING-WATER, ENZYMATIC, HUMAN URINE, HYDRIDE GENERATION, MAMMALIAN SYSTEMS, MASS-SPECTROMETRY, METABOLISM, methylated arsenic, METHYLATION, MONOMETHYLARSONOUS ACID MMA(III), pentavalent arsenic, STABILITY, TOXICITY, trivalent arsenic},
	isbn = {0041-008X},
	url = {<Go to ISI>://000170532300010},
	author = {Del Razo, L. M. and Styblo, M. and Cullen, W. R. and Thomas, D. J.}
}
@article {5136,
	title = {Tetrazole ethers from lignin model phenols: synthesis, crystal structures, and photostability},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {79},
	number = {8},
	year = {2001},
	note = {ISI Document Delivery No.: 473WGTimes Cited: 1Cited Reference Count: 24},
	month = {Aug},
	pages = {1201-1206},
	type = {Article},
	abstract = {{The phenolic OH moiety in lignin is one of the key functional groups responsible for the photo-induced yellowing of mechanical wood pulps and papers. To evaluate new protective groups for the stabilization of lignin phenols, the model compounds, 2-methoxy-4-propylphenol (1) and 4-hydroxy-3-methoxyacetophenone (2) were reacted with 5-chloro-1-phenyl-1H-tetrazole to give the corresponding tetrazole ethers 1{\textquoteright} and 2{\textquoteright}, respectively, that were then studied for their photostability. The synthesis of these ethers was more efficient than that of alkyl ethers because of less hydrolysis of the alkylating agent under the reaction conditions. Compounds 1{\textquoteright} and 2{\textquoteright} were fully characterized, including X-ray crystal structure analyses. Crystals of 1{\textquoteright} and 2{\textquoteright} were monoclinic of space groups P2(1)/c and P2(1)/a, respectively. For 1{\textquoteright}: a = 9.8679(6)},
	keywords = {ALKYLATION, ETHERS, HIGH-YIELD PULPS, LIGHT, LIGNIN MODEL COMPOUNDS, METHYLATION, PHENOLS, yellowing inhibition},
	isbn = {0008-4042},
	url = {<Go to ISI>://000171071400001},
	author = {Lu, A. Z. and Hu, Thomas Q. and Osmond, D. A. and Patrick, B. O. and James, Brian R.}
}
@article {5136,
	title = {Tetrazole ethers from lignin model phenols: synthesis, crystal structures, and photostability},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {79},
	number = {8},
	year = {2001},
	note = {ISI Document Delivery No.: 473WGTimes Cited: 1Cited Reference Count: 24},
	month = {Aug},
	pages = {1201-1206},
	type = {Article},
	abstract = {{The phenolic OH moiety in lignin is one of the key functional groups responsible for the photo-induced yellowing of mechanical wood pulps and papers. To evaluate new protective groups for the stabilization of lignin phenols, the model compounds, 2-methoxy-4-propylphenol (1) and 4-hydroxy-3-methoxyacetophenone (2) were reacted with 5-chloro-1-phenyl-1H-tetrazole to give the corresponding tetrazole ethers 1{\textquoteright} and 2{\textquoteright}, respectively, that were then studied for their photostability. The synthesis of these ethers was more efficient than that of alkyl ethers because of less hydrolysis of the alkylating agent under the reaction conditions. Compounds 1{\textquoteright} and 2{\textquoteright} were fully characterized, including X-ray crystal structure analyses. Crystals of 1{\textquoteright} and 2{\textquoteright} were monoclinic of space groups P2(1)/c and P2(1)/a, respectively. For 1{\textquoteright}: a = 9.8679(6)},
	keywords = {ALKYLATION, ETHERS, HIGH-YIELD PULPS, LIGHT, LIGNIN MODEL COMPOUNDS, METHYLATION, PHENOLS, yellowing inhibition},
	isbn = {0008-4042},
	url = {<Go to ISI>://000171071400001},
	author = {Lu, A. Z. and Hu, Thomas Q. and Osmond, D. A. and Patrick, B. O. and James, Brian R.}
}
@article {5083,
	title = {Unstable trivalent arsenic metabolites, monomethylarsonous acid and dimethylarsinous acid},
	journal = {Journal of Analytical Atomic Spectrometry},
	volume = {16},
	number = {12},
	year = {2001},
	note = {ISI Document Delivery No.: 498MYTimes Cited: 95Cited Reference Count: 52},
	pages = {1409-1413},
	type = {Article},
	abstract = {Two key arsenic metabolites, monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)), have recently been detected in human urine. There is an increasing interest in the speciation of these metabolites in humans because of their demonstrated effects on cellular toxicity and DNA damage. However, there is no information on the oxidative stability of these arsenic species. It is not known whether and to what extent these trivalent metabolites are changed during sample handling and storage. The objective of this study was to demonstrate the oxidative conversion of these arsenic species during sample storage. We compared the effects of the storage temperature (25, 4, and -20 degreesC) and storage duration (up to 5 months) on the stability of MMA(III) and DMA(III) in de-ionized water and in human urine. We used HPLC with hydride generation atomic fluorescence detection for the speciation of arsenic. This method provided sub-mug L-1 to low-mug L-1 detection limits for each arsenic species. We found that the oxidation of MMA(III) and DMA(III) was matrix and temperature dependent. Low temperature conditions (4 and -20 degreesC) improved the stability of these arsenic species over the room temperature storage condition. MMA(III) in de-ionized water was relatively stable for almost 4 months, when stored at 4 or -20 degreesC with less than 10\% of MMA(III) oxidized to MMA(V). In contrast, most of MMA(III) ( 90\%) in urine was oxidized to MMA(V) over the 5 month period under the 4 or -20 degreesC storage condition. At 25 degreesC, MMA(III) in urine was completely oxidized to MMA(V) within a week. DMA(III) in deionized water was stable for only 2-3 days, being rapidly oxidized to DMA(V). DMA(III) in urine was completely oxidized to DMA(V) within a day at 4 or -20 degreesC. The conversion of DMA(III) to DMA(V) in urine at 25 degreesC was complete in 17 h. These results show that MMA(III) and DMA(III) are much less stable than other arsenic species, and their stability depends on sample matrix and temperature.},
	keywords = {ATOMIC FLUORESCENCE DETECTION, BLACKFOOT DISEASE, chemical, DRINKING-WATER, ENZYMATIC, GLUTATHIONE-REDUCTASE, HUMAN HEPATOCYTES, HUMAN URINE, LIQUID-CHROMATOGRAPHY, METHYLATION, RABBIT LIVER, SPECIATION},
	isbn = {0267-9477},
	url = {<Go to ISI>://000172516100011},
	author = {Gong, Z. L. and Lu, X. F. and Cullen, W. R. and Le, X. C.}
}
@article {4942,
	title = {Comparative toxicity of trivalent and pentavalent inorganic and methylated arsenicals in rat and human cells},
	journal = {Archives of Toxicology},
	volume = {74},
	number = {6},
	year = {2000},
	note = {ISI Document Delivery No.: 349ZATimes Cited: 358Cited Reference Count: 37},
	month = {Aug},
	pages = {289-299},
	type = {Article},
	abstract = {Biomethylation is considered a major detoxification pathway for inorganic arsenicals (iAs). According to the postulated metabolic scheme, the methylation of iAs yields methylated metabolites in which arsenic is present in both pentavalent and trivalent forms. Pentavalent mono- and dimethylated arsenicals are less acutely toxic than iAs. However, little is known about the toxicity of trivalent methylated species. In the work reported here the toxicities of iAs and trivalent and pentavalent methylated arsenicals were examined in cultured human cells derived from tissues that are considered a major site for iAs methylation (liver) or targets for carcinogenic effects associated with exposure to iAs (skin, urinary bladder, and lung). To characterize the role of methylation in the protection against toxicity of arsenicals, the capacities of cells to produce methylated metabolites were also examined. In addition to human cells, primary rat hepatocytes were used as methylating controls. Among the arsenicals examined, trivalent monomethylated species were the most cytotoxic in all cell types. Trivalent dimethylated arsenicals were at least as cytotoxic as trivalent iAs (arsenite) for most cell types. Pentavalent arsenicals were significantly less cytotoxic than their trivalent analogs. Among the cell types examined, primary rat hepatocytes exhibited the greatest methylation capacity for iAs followed by primary human hepatocytes, epidermal keratinocytes, and bronchial epithelial cells. Cells derived from human bladder did not methylate iAs. There was no apparent correlation between susceptibility of cells to arsenic toxicity and their capacity to methylate iAs. These results suggest that (1) trivalent methylated arsenicals, intermediary products of arsenic methylation, may significantly contribute to the adverse effects associated with exposure to iAs, and (2) high methylation capacity does not protect cells from the acute toxicity of trivalent arsenicals.},
	keywords = {ARSENATE, arsenic, ARSENITE, BINDING, bladder, cell culture, CELLULAR UPTAKE, DIMETHYLARSINIC ACID, dimethylarsinous acid, DRINKING-WATER, ENZYMATIC METHYLATION, GLUTATHIONE, HEPATOCYTES, HUMAN, IN-VITRO METHYLATION, LIVER, lung, METABOLISM, methylarsonic acid, methylarsonous acid, METHYLATION, RABBIT LIVER, SKIN, TOXICITY},
	isbn = {0340-5761},
	url = {<Go to ISI>://000089074500001},
	author = {Styblo, M. and Del Razo, L. M. and Vega, L. and Germolec, D. R. and LeCluyse, E. L. and Hamilton, G. A. and Reed, W. and Wang, C. and Cullen, W. R. and Thomas, D. J.}
}
@article {4862,
	title = {Determination of monomethylarsonous acid, a key arsenic methylation intermediate, in human urine},
	journal = {Environmental Health Perspectives},
	volume = {108},
	number = {11},
	year = {2000},
	note = {ISI Document Delivery No.: 373XPTimes Cited: 101Cited Reference Count: 48},
	month = {Nov},
	pages = {1015-1018},
	type = {Article},
	abstract = {In this study we report on the finding of monomethylarsonous acid [MMA(III)I in human urine. This newly identified arsenic species is a key intermediate in the metabolic pathway of arsenic biomethylation, which involves stepwise reduction of pentavalent to trivalent arsenic species followed by oxidative addition of a methyl group. Arsenic speciation was carried out using ion-pair chromatographic separation of arsenic compounds with hydride generation atomic fluorescence spectrometry detection. Speciation of the inorganic arsenite [As(III)], inorganic arsenate [As(V)], monomethylarsonic acid [MMA(V)], dimethylarsinic acid [DMA(V)], and MMA(III) in a urine sample was complete in 5 min. Urine samples collected from humans before and after a single oral administration of 300 mg sodium 2,3-dimercapto-1-propane sulfonate (DMPS) were analyzed for arsenic species. MMA(III) was found in 51 out of 123 urine samples collected from 41 people in inner Mongolia 0-6 hr after the administration of DMPS. MMA(III)in urine samples did not arise from the reduction of MMA(V) by DMPS. DMPS probably assisted the release of MMA(III) that was formed in the body. Along with the presence of MMA(III), there was an increase in the relative concentration of MMA(V) and a decrease in DMA(V) in the urine samples collected after the DMPS ingestion.},
	keywords = {3-dimercapto-1-propane sulfonate, ARSENIC SPECIATION, BIOMARKERS, CARCINOGENESIS, CHEMICAL FORMS, DIMETHYLARSINIC ACID, ENZYMATIC METHYLATION, EXCRETION, EXPOSURE, GLUTATHIONE-REDUCTASE, INGESTION, METABOLISM, METABOLITES, METHYLATION, MONOMETHYLARSONOUS ACID, sodium 2, SPECIATION, trivalent methylarsenic species, urine metabolites},
	isbn = {0091-6765},
	url = {<Go to ISI>://000165315600019},
	author = {Le, X. C. and Ma, M. S. and Lu, X. F. and Cullen, W. R. and Aposhian, H. V. and Zheng, B. S.}
}
@article {4833,
	title = {Removal of phenolic hydroxyl groups in lignin model compounds and its effect on photostability},
	journal = {Holzforschung},
	volume = {54},
	number = {2},
	year = {2000},
	note = {ISI Document Delivery No.: 301QHTimes Cited: 3Cited Reference Count: 24},
	pages = {127-132},
	type = {Article},
	abstract = {The phenolic hydroxyl groups in the lignin model compounds, 2-methoxy-4-propylphenol and 4-hydroxy-3-methoxyacetophenone, were removed by first converting the hydroxyl groups to the trifluoromethanesulfonates (triflates) and then cleaving the triflate substituents via catalytic hydrogen transfer. The products, 1-methoxy-3-propylbenzene and 3-methoxyacelophenone: were characterized by H-1 and C-13 NMR, mass spectrometry and elemental analyses. The effect of the removal of the phenolic groups on the photostability of the model compounds was evaluated by impregnating the compounds into Whatman filter paper sheets, and subjecting them to an accelerated yellowing experiment in a UV chamber. The removal of the phenolic groups resulted in a significant yellowing inhibition, with a higher photostabilizing effect than methylation or acetylation of the hydroxyl, particularly for the model compound without an alpha-carbonyl group.},
	keywords = {ACETYLATION, DEGRADATION, DEOXYGENATION, GROUPS, HYDROGENATION, LIGNIN MODEL COMPOUNDS, METAL, METHYLATION, phenolic hydroxyl, photostability yellowing, REDUCTION},
	isbn = {0018-3830},
	url = {<Go to ISI>://000086320500004},
	author = {Hu, Thomas Q. and Cairns, G. R. and James, Brian R.}
}
@article {4833,
	title = {Removal of phenolic hydroxyl groups in lignin model compounds and its effect on photostability},
	journal = {Holzforschung},
	volume = {54},
	number = {2},
	year = {2000},
	note = {ISI Document Delivery No.: 301QHTimes Cited: 3Cited Reference Count: 24},
	pages = {127-132},
	type = {Article},
	abstract = {The phenolic hydroxyl groups in the lignin model compounds, 2-methoxy-4-propylphenol and 4-hydroxy-3-methoxyacetophenone, were removed by first converting the hydroxyl groups to the trifluoromethanesulfonates (triflates) and then cleaving the triflate substituents via catalytic hydrogen transfer. The products, 1-methoxy-3-propylbenzene and 3-methoxyacelophenone: were characterized by H-1 and C-13 NMR, mass spectrometry and elemental analyses. The effect of the removal of the phenolic groups on the photostability of the model compounds was evaluated by impregnating the compounds into Whatman filter paper sheets, and subjecting them to an accelerated yellowing experiment in a UV chamber. The removal of the phenolic groups resulted in a significant yellowing inhibition, with a higher photostabilizing effect than methylation or acetylation of the hydroxyl, particularly for the model compound without an alpha-carbonyl group.},
	keywords = {ACETYLATION, DEGRADATION, DEOXYGENATION, GROUPS, HYDROGENATION, LIGNIN MODEL COMPOUNDS, METAL, METHYLATION, phenolic hydroxyl, photostability yellowing, REDUCTION},
	isbn = {0018-3830},
	url = {<Go to ISI>://000086320500004},
	author = {Hu, Thomas Q. and Cairns, G. R. and James, Brian R.}
}
@article {4861,
	title = {Speciation of key arsenic metabolic intermediates in human urine},
	journal = {Analytical Chemistry},
	volume = {72},
	number = {21},
	year = {2000},
	note = {ISI Document Delivery No.: 369XXTimes Cited: 187Cited Reference Count: 45},
	month = {Nov},
	pages = {5172-5177},
	type = {Article},
	abstract = {Biomethylation is the major human metabolic pathway for inorganic arsenic, and the speciation of arsenic metabolites is essential to a better understanding of arsenic metabolism and health effects. Here we describe a technique for the speciation of arsenic in human urine and demonstrate its application to the discovery of key arsenic metabolic intermediates, monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)), in human urine. The study provides a direct evidence in support of the proposed arsenic methylation pathway in the human. The finding of MMA(III) and DMA(III) in human urine, along with recent studies showing the high toxicity of these arsenicals, suggests that the usual belief of arsenic detoxification by methylation needs to be reconsidered, The arsenic speciation technique is based on ion pair chromatographic separation of arsenic species on a 3-mum particle size column at 50 degreesC followed by hydride generation atomic fluorescence detection. Speciation of MMA(III), DMA(III), arsenite (As-III), arsenate (As-V), monomethylarsonic acid(MMA(V)), and dimethylarsinic acid (DMA(V)) in urine samples is complete in 6 min with detection limits of 0.5-2 mug/L. There is no need for any sample pretreatment. The capability of rapid analysis of trace levels of arsenic species, which resulted in the findings of the key metabolic intermediates, makes the technique useful for routine arsenic speciation analysis required for toxicological and epidemiological studies.},
	keywords = {ATOMIC FLUORESCENCE DETECTION, BLACKFOOT DISEASE, DRINKING-WATER, EXCRETION, EXPOSURE, INGESTION, METHYLATION, PERFORMANCE LIQUID-CHROMATOGRAPHY, SEPARATION, TEMPERATURE},
	isbn = {0003-2700},
	url = {<Go to ISI>://000165094000012},
	author = {Le, X. C. and Lu, X. F. and Ma, M. S. and Cullen, W. R. and Aposhian, H. V. and Zheng, B. S.}
}
@article {3289,
	title = {ARSENIC BIOMETHYLATION BY THE MICROORGANISM APIOTRICHUM HUMICOLA IN THE PRESENCE OF L-METHIONINE-METHYL-D(3)},
	journal = {Applied Organometallic Chemistry},
	volume = {9},
	number = {7},
	year = {1995},
	note = {ISI Document Delivery No.: TG189Times Cited: 15Cited Reference Count: 273rd International Conference on Environmental and Biological Aspects of Main Group Organometals (ICEBAMO 94)SEP, 1994BORDEAUX, FRANCESoc Francaise Chim, Royal Soc Chem, CNRS, EC Measurement \& Testing Program, French Minist Environm, French Minist Res \& Technol, Univ Bordeaux I, Univ Bordeaux II, IFREMER, INRA, Conseil Reg Aquitaine, Lyonnaise Eaux Dumez Water Co., Thermo Jarell Ash, John Wiley \& Sons, Freund Publ, Elsevier Sci Publ},
	month = {Nov},
	pages = {507-515},
	type = {Proceedings Paper},
	abstract = {The microorganism Apiotrichum humicola (previously known as Candida humicola) grown in the presence of either arsenate, arsenite, methyl-arsonic acid or dimethylarsinic acid, produces arsenic-containing metabolites in the growth medium. When L-methionine-methyl-d(3) is added to the cultures, the CD3 label is incorporated intact into the metabolites to a considerable extent to form deuterated dimethylarsenic and trimethylarsenic species, indicating that S-adenosylmethionine, or some related sulphonium compound, is involved in the biological methylation. Conclusive evidence of CD3 incorporation in the arsenicals found in the growth medium was provided by using a specially developed hydride generation-gas chromatography-mass spectrometry system (HG-GC-MS).},
	keywords = {ARSENATE, ARSENITE, CHROMATOGRAPHY MASS SPECTROMETRY, DIMETHYLARSINIC ACID, EXTRACELLULAR, GAS, HYDRIDE GENERATION, HYDRIDE GENERATION GAS, L-METHIONINE-METHYL-D(3), methylarsonic acid, METHYLATION, MICROORGANISM, REDUCTION, S-ADENOSYLMETHIONINE, THIOLS, TRIMETHYLARSINE OXIDE},
	isbn = {0268-2605},
	url = {<Go to ISI>://A1995TG18900002},
	author = {Cullen, W. R. and Li, H. and Pergantis, S. A. and Eigendorf, G. K. and Mosi, A. A.}
}
@article {3000,
	title = {BIOACCUMULATION AND EXCRETION OF ARSENIC COMPOUNDS BY A MARINE UNICELLULAR ALGA, POLYPHYSA-PENICULUS},
	journal = {Applied Organometallic Chemistry},
	volume = {8},
	number = {4},
	year = {1994},
	note = {ISI Document Delivery No.: PD643Times Cited: 27Cited Reference Count: 43},
	month = {Jul},
	pages = {313-324},
	type = {Article},
	abstract = {Polyphysa peniculus was grown in artificial sea-water in the presence of arsenate, arsenite, monomethylarsonate and dimethylarsinic acid. The separation and identification of some of the arsenic species produced in the cells as well as in the growth medium were achieved by using hydride generation-gas chromatography-atomic absorption spectrometry methodology. Arsenite and dimethylarsinate were detected following incubation with arsenate. When the alga was treated with arsenite, dimethylarsinate was the major metabolite in the cells and in the growth medium; trace amounts of monomethylarsonate were also detected in the cells. With monomethylarsonate as a substrate, the metabolite is dimethylarsinate. Polyphysa peniculus did not metabolize dimethylarsinic acid when it was used as a substrate. Significant amounts of more complex arsenic species, such as arsenosugars, were not observed in the cells or medium on the evidence of flow injection-microwave digestion-hydride generation-atomic absorption spectrometry methodology. Transfer of the exposed cells to fresh medium caused release of most cell-associated arsenicals to the surrounding environment.},
	keywords = {ARSENIC BIOACCUMULATION, ARSENIC METYLATION, arsenic species, ARSENIC UPTAKE, COMPOUNDS, CONTAINING RIBOFURANOSIDES, ENVIRONMENT, IDENTIFICATION, KELP ECKLONIA-RADIATA, METABOLISM, METHYLATION, NON-REDUCIBLE ARSENICALS, ORGANOARSENIC, PHYTOPLANKTON, POLYPHYSA-PENICULUS, RIVER BEAULIEU, SPECIATION},
	isbn = {0268-2605},
	url = {<Go to ISI>://A1994PD64300004},
	author = {Cullen, W. R. and Harrison, L. G. and Li, H. and Hewitt, G.}
}
@article {3002,
	title = {IDENTIFICATION OF EXTRACELLULAR ARSENICAL METABOLITES IN THE GROWTH-MEDIUM OF THE MICROORGANISMS APIOTRICHUM-HUMICOLA AND SCOPULARIOPSIS-BREVICAULIS},
	journal = {Applied Organometallic Chemistry},
	volume = {8},
	number = {4},
	year = {1994},
	note = {ISI Document Delivery No.: PD643Times Cited: 34Cited Reference Count: 28},
	month = {Jul},
	pages = {303-311},
	type = {Article},
	abstract = {The separation and identification of some of the arsenic species produced in cells present in the growth medium when the microorganisms Apiotrichum humicola (previously known as Candida humicola) and Scopulariopsis brevicaulis were grown in the presence of arsenicals were achieved by using hydride generation-gas chromatography-atomic absorption spectrometry methodology (HG GC AA). Arsenite, monomethylarsonate, dimethylarsinate and trimethylarsine oxide were detected following incubation with arsenate. With arsenite as a substrate, the metabolites were monomethylarsonate, dimethylarsinate and trimethylarsine oxide; monomethylarsonate afforded dimethylarsinate and trimethylarsine oxide, and dimethylarsinate afforded trimethylarsine oxide. Trimethylarsine was not detected when the arsenic concentration was 1 ppm.},
	keywords = {APIOTRICHUM-HUMICOLA, arsenic, CANDIDA-HUMICOLA, DIMETHYULARSINATE, ENDOCELLULAR, EXTRACELLULAR, GROWTH MEDIUM, HYDRIDE GENERATION GAS CHROMATOGRAPHY ATOMIC ABSORPTION SPECTROMETRY, METHYLARSONATE, METHYLATION, mobility, SCOPULARIOPSIS-BREVICAULIS, TRIMETHYLARSINE, TRIMETHYLARSINE OXIDE},
	isbn = {0268-2605},
	url = {<Go to ISI>://A1994PD64300003},
	author = {Cullen, W. R. and Li, H. and Hewitt, G. and Reimer, K. J. and Zalunardo, N.}
}
@article {3003,
	title = {THE METHYLATION OF ARSENATE BY A MARINE ALGA POLYPHYSA-PENICULUS IN THE PRESENCE OF L-METHIONINE-METHYL-D(3)},
	journal = {Chemosphere},
	volume = {28},
	number = {5},
	year = {1994},
	note = {ISI Document Delivery No.: NC959Times Cited: 13Cited Reference Count: 39},
	month = {Mar},
	pages = {1009-1019},
	type = {Article},
	abstract = {Polyphysa peniculus growing in artificial seawater methylates arsenate to produce a dimethylarsenic derivative, probably dimethylarsinate. When L-methionine-methyl-d3 is added to the culture the CD3 label is incorporated intact in the dimethylarsenic compound to a considerable extent, indicating that S-adenosylmethionine, or some related sulphonium compound, is involved in the biological methylation. Conclusive evidence of the CD3 incorporation was provided by using a specially developed hydride generation-gas chromatography-mass spectrometry methodology.},
	keywords = {ALGAE, arsenic, COMPOUNDS, CONTAINING RIBOFURANOSIDES, ENVIRONMENT, GENERATION GAS CHROMATOGRAPHY MASS SPECTROMETRY (HG-GC-MS), hydride, IDENTIFICATION, KELP ECKLONIA-RADIATA, L-METHIONINE-METHYL-D(3), METHYLARSENIC COMPOUNDS, METHYLATION, NATURAL-WATERS, ORGANOARSENIC, REDUCTION, SPECIATION, SPECTROMETRY},
	isbn = {0045-6535},
	url = {<Go to ISI>://A1994NC95900016},
	author = {Cullen, W. R. and Li, H. and Pergantis, S. A. and Eigendorf, G. K. and Harrison, L. G.}
}
@article {2770,
	title = {BIOTRANSFORMATION OF [H-3] METHYLARSONIC ACID IN A STATIC SEAWATER SYSTEM CONTAINING MYTILUS-CALIFORNIANUS},
	journal = {Applied Organometallic Chemistry},
	volume = {7},
	number = {5},
	year = {1993},
	note = {ISI Document Delivery No.: LV681Times Cited: 8Cited Reference Count: 24},
	month = {Sep},
	pages = {329-334},
	type = {Article},
	abstract = {Mytius californianus exposed for 9 days to a seawater system containing [H-3]methylarsonic acid, was found to contain [H-3]methylarsonic acid along with [H-3]arsenobetaine and two unknown H-3-labeled compounds in the tissue parts of the mussel. A linear increase with time in the specific activity present in the flesh of Mytilus californianus was also observed. The highest specific activity was found in the visceral mass and the gills of the mussel.},
	keywords = {ALGAE, ARSENIC SPECIATION, arsenobetaine, ARSENOCHOLINE, BIOACCUMULATION, H-3 LABEL, IDENTIFICATION, marine environment, methylarsonic acid, METHYLATION, mussel, ORGANOARSENIC},
	isbn = {0268-2605},
	url = {<Go to ISI>://A1993LV68100005},
	author = {Cullen, W. R. and Pergantis, S. A.}
}
