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dc.contributor.authorDiesel, Elizabeth A.en_US
dc.date.accessioned2014-03-14T21:09:37Z
dc.date.available2014-03-14T21:09:37Z
dc.date.issued2011-02-04en_US
dc.identifier.otheretd-02182011-142724en_US
dc.identifier.urihttp://hdl.handle.net/10919/37383
dc.description.abstractDrinking water supplies contaminated with arsenic (As), a toxin and carcinogen, adversely impact the health of millions of people worldwide. Previous work has documented that different inorganic and organic As species vary with respect to their toxicities. It is, however, currently not well understood how As speciation affects bioavailability, defined as the capacity of a contaminant to cross an organismâ s cellular membrane, or how arsenicâ s form (dissolved vs. non-dissolved) can affect bioavailability. This dissertation addresses the effect of speciation and form on As bioavailability through a combination of field and laboratory studies. In the first project, a poultry litter application experiment was conducted to determine if trace elements (As, Cu, and Zn) are released from litter to underlying soil water, and if so, whether the trace elements are present in dissolved form or complexed to nanoparticles, colloids, or particles. Results showed that Cu and Zn released from the litter were dominantly complexed to organic matter or to iron oxides/clay particles, while As was dominantly dissolved or complexed to organic matter. In the second project, a luminescent E. coli bioreporter was created and exposed to different As species, including As(III), As(V), MSMA, and roxarsone. Results showed variable response, with As(III) producing the strongest response, followed by As(V) and MSMA; roxarsone showed no response. The bioreporter was exposed to As solutions with varying cation concentrations to examine the impact of sample geochemistry on performance. Increased monovalent (Na,K) concentrations enhanced luminescent response, while increased divalent (Ca) concentrations inhibited response. These altered responses reflect different As uptake pathways into the cell. The third study addressed bioavailability of As species to Corbicula fluminea, a clam commonly used for biomonitoring. Results demonstrate that As(III) is most bioavailable to Corbicula, followed by As(V), MSMA, and roxarsone. Corbicula also displayed the ability to change As speciation through internal processing and via their shell, demonstrating that Corbicula can affect As speciation in solution. Results of these studies enhance the scientific knowledge of how speciation and form affect As bioavailability, and can also inform regulators who use bioavailability to set remediation goals for As-contaminated systems.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartDiesel_EA_D_2011.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectarsenicen_US
dc.subjectorganoarsenicalen_US
dc.subjectbioavailabilityen_US
dc.subjectspeciationen_US
dc.subjectE. colien_US
dc.subjectC. flumineaen_US
dc.subjectcolloiden_US
dc.subjectnanoparticleen_US
dc.titleThe Effect of Speciation and Form on the Bioavailability of Arsenic: Insight into the Behavior of Arsenic in Natural Watersen_US
dc.typeDissertationen_US
dc.contributor.departmentGeosciencesen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineGeosciencesen_US
dc.contributor.committeechairSchreiber, Madeline E.en_US
dc.contributor.committeememberVikesland, Peter J.en_US
dc.contributor.committeemembervan der Meer, Janen_US
dc.contributor.committeememberHochella, Michael F. Jr.en_US
dc.contributor.committeememberRimstidt, James Donalden_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-02182011-142724/en_US
dc.date.sdate2011-02-18en_US
dc.date.rdate2011-03-15
dc.date.adate2011-03-15en_US


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