Transformation of 2,4-dichlorophenoxyacetic acid in four different marine and estuarine sediments: effects of sulfate, hydrogen and acetate on dehalogenation and side-chain cleavage

Citation
Aw. Boyle et al., Transformation of 2,4-dichlorophenoxyacetic acid in four different marine and estuarine sediments: effects of sulfate, hydrogen and acetate on dehalogenation and side-chain cleavage, FEMS MIC EC, 29(1), 1999, pp. 105-113
Citations number
38
Categorie Soggetti
Biology,Microbiology
Journal title
FEMS MICROBIOLOGY ECOLOGY
ISSN journal
01686496 → ACNP
Volume
29
Issue
1
Year of publication
1999
Pages
105 - 113
Database
ISI
SICI code
0168-6496(199905)29:1<105:TO2AIF>2.0.ZU;2-D
Abstract
Enrichments initiated with marine and estuarine sediments from the Arthur K ill (NY/MJ estuary) and Paleta Creek (San Diego Bay, CA), transformed 2,4-d ichlorophenoxyacetic acid to 4-chlorophenol in the presence of sulfate (25 mM). Transformation of 2,4-dichlorophenoxyacetic acid was not observed with two other marine sediments from Tuckerton, NJ and Flax Pond (Stony Brook, NY). The lag period prior to 2,4-dichlorophenoxyacetic acid loss or the lim e required for 50% removal of 2,4-dichlorophenoxyacetic acid (t(50)) in Art hur Kill and San Diego enrichments was not affected by the presence of sulf ate, although the addition of hydrogen and acetate decreased the lag period s and t(50) values in these enrichments. The first step in the transformati on of 2,4-dichlorophenoxyacetic acid was side-chain removal forming 2,4,dic hlorophenol which was then dechlorinated to 4-chlorophenol. Second-generati on Arthur Kill cultures dechlorinated 2,4-dichlorophenoxyacetic acid to 4-c hlorophenoxyacetic acid. This dechlorination occurred both in the presence and absence of sulfate (25 mM); however, sulfate reduced the rate of dechlo rination by approximately 50%. Second-generation cultures inoculated with t he sulfate-amended enrichments consumed sulfate and dechlorinated 2,4-dichl orophenoxyacetic acid to 4-chlorophenoxyacetic acid concurrently when suppl ied with hydrogen and acetate; the rate of dechlorination was twice that of cultures that did not receive hydrogen and acetate. Sulfate consumption oc curred only in cultures supplemented with hydrogen and acetate. These resul ts indicate that dechlorination of an organochlorine pesticide in marine an d estuarine sediments occurs in the presence of sulfate and the addition of readily utilizable carbon and electron donors can stimulate dechlorinating activity. (C) 1999 Federation of European Microbiological Societies. Publi shed by Elsevier Science B.V. All rights reserved.