Biodegradation of dichloromethane in an estuarine environment

Dichloromethane (DCM) is a toxic pollutant showing prolonged persistence in water. So far, biodegradation of DCM has only been reported in soils and freshwater systems. Herein, we studied whether or not biodegradation of DCM could occur in estuarine waters. Results showed over 90% mineralization of DCM in natural estuarine waters supplemented with DCM. Biodegradation of DCM in estuarine waters occurred by association of different bacterial species. Generally, two bacterial species participated in DCM degradation. Two bacterial consortia were obtained. Consortia were able to degrade around 80% of DCM in about 6 days. The species involved in the process were identified by 16S rRNA gene sequencing; a consortium was constituted by Pseudomonas sp. and Brevundimonas sp. and a second consortium was formed by Pseudomonas sp. and an Acinetobacter sp. Our results showed that DCM can be readily biodegraded in estuarine waters.Peer Reviewe

Bacterial degradation of dichloromethane in cultures and natural environments

Dichloromethane (DCM) is a toxic pollutant showing prolonged persistence in water. DCM biodegradation is usually determined from increases in Cl ions, gas chromatography, or by using radioisotopes. Herein, we present an original and easy spectrophotometric method to estimate DCM concentrations in cultures and environmental samples during DCM biodegradation experiments.Valentina I. Krausova acknowledges her support from a Fulbright fellowship to perform her work at the Center of Marine Biotechnology. Frank T. Robb and Juan M. González were supported in part by an NSF LEXEN grant. Juan M. Gonza´lez is supported by grants from the Spanish Ministry of Science and Technology (Ramón y Cajal Program and REN2002- 00041/GLO).Peer Reviewe