@article {3093, title = {HUMAN URINARY ARSENIC EXCRETION AFTER ONE-TIME INGESTION OF SEAWEED, CRAB, AND SHRIMP}, journal = {Clinical Chemistry}, volume = {40}, number = {4}, year = {1994}, note = {ISI Document Delivery No.: NE582Times Cited: 145Cited Reference Count: 48}, month = {Apr}, pages = {617-624}, type = {Article}, abstract = {We studied chemical speciation of arsenic compounds in urine samples by using HPLC with inductively coupled plasma mass spectrometry detection. We examined urinary arsenic excretion patterns and the arsenic species excreted from nine human subjects who ingested seaweed products and crab (or shrimp). Fast urinary excretion of unchanged arsenobetaine was seen after ingestion of crab and shrimp, which contain arsenobetaine as the major arsenic species. In contrast, the arsenosugars, which comprise the major arsenic species in seaweed, are metabolized and have a longer retention time in the human body. When nine volunteers ingested the commercial seaweed product nori, both the urinary arsenic excretion pattern and the excreted arsenic species varied from individual to individual, and as many as six metabolites could be detected. It seems that arsenosugars are not decomposed by stomach acid and that reactions involving enzymatic and (or) microbial activity in the human body may be responsible for the metabolism of arsenosugars.}, keywords = {arsenobetaine, arsenosugars, ATOMIC-ABSORPTION SPECTROMETRY, EDIBLE, HAMSTER, JAPANESE, METABOLISM, ORGANOARSENIC COMPOUNDS, PLASMA, RABBITS, SEAWEED, SPECIATION, TOXICOLOGY}, isbn = {0009-9147}, url = {://A1994NE58200023}, author = {Le, X. C. and Cullen, W. R. and Reimer, K. J.} } @article {3092, title = {SPECIATION OF ARSENIC COMPOUNDS BY HPLC WITH HYDRIDE GENERATION ATOMIC-ABSORPTION SPECTROMETRY AND INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY DETECTION}, journal = {Talanta}, volume = {41}, number = {4}, year = {1994}, note = {ISI Document Delivery No.: NJ813Times Cited: 94Cited Reference Count: 45}, month = {Apr}, pages = {495-502}, type = {Article}, abstract = {An arsenic specific detection system utilizing on-line microwave digestion and hydride generation atomic absorption spectrometry (MD/HGAAS) is described for arsenic speciation by using high performance liquid chromatography (HPLC). Both ion exchange chromatography and ion pair chromatography have been studied for the separation of arsenite, arsenate, monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA), and arsenobetaine (AB). When the commonly used mobile phases, phosphate and carbonate buffers at pH 7.5, are used on an anion exchange column, arsenite and AB co-elute. However, selective determination of these two arsenic compounds can be achieved by using the new detection system. Partial separation between arsenite and AB can be achieved by increasing the mobile phase pH to 10.3 and by using a polymer based anion exchange column. The detection limit obtained by using anion exchange chromatography with MD/HGAAS detection is approximately 10 ng/ml (or 200 pg for a 20-mul sample injection) for arsenite, DMAA and AB, 15 ng/ml (or 300 pg) for MMAA, and 20 ng/ml (or 400 pg) for arsenate. Complete separation of the five arsenic compounds is achieved on a reversed phase C18 column by using sodium heptanesulfonate as ion pair reagent. Comparable resolution between chromatographic peaks is obtained by using MD/HGAAS detection and inductively coupled plasma mass spectrometry (ICPMS) detection.}, keywords = {ELEMENT-SPECIFIC DETECTOR, IDENTIFICATION, ION CHROMATOGRAPHY, MUSCLE, ORGANOARSENIC COMPOUNDS, PERFORMANCE LIQUID-CHROMATOGRAPHY, QUANTITATION, REFERENCE MATERIAL, SEPARATION, TRACE-ELEMENTS, WATER}, isbn = {0039-9140}, url = {://A1994NJ81300003}, author = {Le, X. C. and Cullen, W. R. and Reimer, K. J.} } @article {3091, title = {SPECIATION OF ARSENIC COMPOUNDS IN SOME MARINE ORGANISMS}, journal = {Environmental Science \& Technology}, volume = {28}, number = {9}, year = {1994}, note = {ISI Document Delivery No.: PE258Times Cited: 43Cited Reference Count: 49}, month = {Sep}, pages = {1598-1604}, type = {Article}, abstract = {Speciation of arsenic compounds in some marine algae, bivalves, and crustaceans was studied by using two techniques: (i) high-performance liquid chromatography with inductively coupled plasma mass spectrometry detection and (ii) hydride generation atomic absorption spectrometry following microwave-assisted digestion. Arsenosugars were identified as the major arsenic compounds present in marine algae, whereas arsenobetaine was the dominant arsenic species present in crab and shrimp. In contrast to most previous reports, which claimed arsenobetaine as the only major arsenic species present in marine bivalves, this study revealed the presence of arsenosugars in addition to arsenobetaine in the bivalves. The speciation of arsenic in sample extracts and {\textquoteright}{\textquoteright}defrost liquid{\textquoteright}{\textquoteright} from previously frozen marine animal samples revealed that up to 48\% of the total arsenic in the sample can be released in the defrost liquid. Arsenic species found in the defrost liquid were identical with those in the sample extracts. Changes in arsenic speciation were observed in the sample extracts that were stored for a long term. Arsenobetaine in sample extracts that were stored at 4 degrees C for 9 months was decomposed to trimethylarsine oxide and two other unidentified arsenic species.}, keywords = {ARSENIC COMPOUNDS, arsenobetaine, ATOMIC-ABSORPTION SPECTROMETRY, BOMBARDMENT MASS-SPECTROMETRY, ECKLONIA-RADIATA, HOMARUS-AMERICANUS, IDENTIFICATION, KELP, ORGANOARSENIC COMPOUNDS, TRACE-ELEMENTS, TRIMETHYLARSINE OXIDE}, isbn = {0013-936X}, url = {://A1994PE25800015}, author = {Le, S. X. C. and Cullen, W. R. and Reimer, K. J.} }