Arsenic sequestration by nitrate respiring microbial communities in urban lake sediments.

TitleArsenic sequestration by nitrate respiring microbial communities in urban lake sediments.
Publication TypeJournal Article
Year of Publication2007
AuthorsGibney BP, Nüsslein K
JournalChemosphere
Volume70
Issue2
Pagination329-36
Date Published2007 Dec
ISSN0045-6535
KeywordsArsenic, Betaproteobacteria, Biodegradation, Environmental, DNA, Bacterial, DNA, Ribosomal, Fresh Water, Geologic Sediments, Massachusetts, Nitrates, Oxidation-Reduction, RNA, Ribosomal, 16S, Urbanization, Water Microbiology, Water Pollutants, Chemical
Abstract

Changes in microbial community composition and activity were related to geochemical conditions favoring arsenic sequestration in sediments collected from the urban, arsenic-contaminated Upper Mystic Lake. After amendment with nitrate, >94% total soluble arsenic is sequestered by Fe(III)-(oxy)hydroxides generated in live sediments. Of this sequestered arsenic, >75% existed as As(III), indicating As redox state alone is not responsible for changes in mobility. Arsenic sequestration was concurrent with the microbial respiration of nitrate as indicated by steady state hydrogen concentration and the presence of organisms similar to nitrate-reducing, iron-oxidizing bacteria belonging to the genus Dechloromonas in 16S rDNA clone libraries.

DOI10.1016/j.chemosphere.2007.05.094
Alternate JournalChemosphere
PubMed ID17935754