Enhanced 1,2-dichloroethane degradation in heavy metal co-contaminated wastewater undergoing biostimulation and bioaugmentation.

Biostimulation, bioaugmentation and dual-bioaugmentation strategies were investigated in this study for efficient bioremediation of water co-contaminated with 1,2-dichloroethane (1,2-DCA) and heavy metals, in a microcosm set-up. 1,2-DCA concentration was periodically measured in the microcosms by gas chromatographic analysis of the headspace samples, while bacterial population and diversity were determined by standard plate count technique and Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) analysis, respectively. Dual-bioaugmentation, proved to be most effective exhibiting 22.

Kinetics of heavy metal inhibition of 1,2-dichloroethane biodegradation in co-contaminated water.

Sites co-contaminated with heavy metals and 1,2-DCA may pose a greater challenge for bioremediation, as the heavy metals could inhibit the activities of microbes involved in biodegradation. Therefore, this study was undertaken to quantitatively assess the effects of heavy metals (arsenic, cadmium, mercury, and lead) on 1,2-DCA biodegradation in co-contaminated water. The minimum inhibitory concentrations (MICs) and concentrations of the heavy metals that caused half-life doubling (HLDs) of 1,2-DCA as well as the degradation rate coefficient (k(1)) and half-life (t(½)) of 1,2-DCA were measured and used to predict the toxicity of the heavy metals in the water microcosms.