Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1021/es9006788
Titel (primär) Natural attenuation potential of phenylarsenicals in anoxic groundwaters
Autor Hempel, M.; Daus, B.; Vogt, C.; Weiss, H. ORCID logo
Quelle Environmental Science & Technology
Erscheinungsjahr 2009
Department ISOBIO; ANA; GWS
Band/Volume 43
Heft 18
Seite von 6989
Seite bis 6995
Sprache englisch
Abstract The extensive production of chemical warfare agents in the 20th century has led to serious contamination of soil and groundwater with phenyl arsenicals at former ammunition depots or warfare agent production sites worldwide. Most phenyl arsenicals are highly toxic for humans. The microbial degradation of phenylarsonic acid (PAA) and diphenylarsinic acid (DPAA) was investigated in microcosms made of anoxic groundwater/sediment mixtures taken from different depths of an anoxic, phenyl arsenical contaminated aquifer in Central Germany. DPAA was not transformed within 91 days incubation time in any of the microcosms. The removal of PAA can be described by a first order kinetics without a lag-phase (rate: 0.037 d-1). In sterilized microcosms, PAA concentrations always remained stable, demonstrating that PAA transformation was a biologically mediated process. PAA transformation occurred under sulfate-reducing conditions due to sulfate consumption and production of sulfide. The addition of lactate (1 mM), a typical substrate of sulfate-reducing bacteria, increased the transformation rate of PAA significantly up to 0.134 d-1. The content of total arsenic was considerably reduced (>75%). Intermediates of PAA transformation were detected by high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Experiments with a pure strain and sterile controls of Desulfovibrio gigas spiked with PAA showed that the elimination process is linked to the presence of sulfide formed through bacterial activity. Phenyl arsenicals were likely immobilized in the sediment through sulfur substitution and a subsequent sulfur bond under the prevailing sulfate reducing condition. The results of this study indicate that PAA can undergo microbiologically mediated transformation in anoxic aquifers, leading to reduced concentrations in groundwater, which indicate a (enhancend) natural attenuation potential.
dauerhafte UFZ-Verlinkung
Hempel, M., Daus, B., Vogt, C., Weiss, H. (2009):
Natural attenuation potential of phenylarsenicals in anoxic groundwaters
Environ. Sci. Technol. 43 (18), 6989 - 6995 10.1021/es9006788