CHEMICAL, MICROBIOLOGICAL, AND ECOTOXICOLOGICAL MONITORING OF BIODEGRADATION IN PAH-CONTAMINATED SEDIMENTS

摘要

This study was performed in order to evaluate factors that influence the magnitude and rates of PAH biodegradation processes in contaminated sediments at a laboratory scale. Several factors influence the feasibility and effectiveness of sediment biodegradation: (1) the existence of an indigenous sediment microbial population capable of degrading PAH contaminants, (2) the availability of the contaminants to sediment microbial population (bioavailability), (3) the optimization of environmental factors such as temperature and oxygen, and nutrients availability, (4) the influence of a natural surfactant on PAH degradation velocity. The rate and extent of PAH biodegradation were evaluated by sediment-slurry experiments by monitoring chemical, microbiological and ecotoxicological parameters. The last focus of our work was to investigate the source and the extent of toxicity in slurry experiments using the Microtox? test both on solid and liquid phases, in order to determine any enhancement or shift in toxicity over the time and/or between the solid and liquid phases due to release or increased bioavailability of the target contaminants.