||Reductive Transformations of Halogenated Aromatic Hydrocarbons in Anaerobic Water-Sediment Systems: Kinetics, Mechanisms and Products.
Peunenburg, W. J. G. M. ;
't Hart, M. J. ;
den Hollander, H. A. ;
van de Meent., D. ;
||Environmental Research Lab., Athens, GA. Office of Research and Development. ;Rijksinstituut voor de Volksgezondheid en Milieuhygiene, Bilthoven (Netherlands). Lab. for Ecotoxicology, Environmental Chemistry and Drinking Water.
Halogen aromatic hydrocarbons ;
Water pollution ;
Anaerobic conditions ;
Reaction kinetics ;
Structure activity relationships ;
Oxidation reduction reactions ;
Sediment-water interfaces ;
Methane bacteria ;
Environmental persistence ;
Microbial degradation ;
Quantitative Structure-Activity Relationship ;
Chemical reaction mechanisms
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
The degradation of several classes of halogenated aromatic hydrocarbons in methanogenic sediment-water systems was examined in laboratory studies. Several transformation processes were shown to occur, leading to formation of a variety of products. In the study a clear distinction could be made between transformation processes taking place immediately upon incubation of the compounds and processes taking place after a characteristic period of varying length. y-Irradiation was used to quench biological reactions and thus assess the impact of those processes on the overall rates of degradation of the studied compounds. The kinetics of both the initial and the final processes were pseudo-first-order, with half-lives ranging from <0.46 d to no detectable degradation for a number of multiple halogenated benzenes. Compounds were selected with the aim of obtaining a maximum variation in chemical reactivity and physical properties. The sediments were selected with the aim of assessing several environmental factors influencing the kinetics of reduction. (Copyright (c) 1992 SETAC.)