Degradation patterns in sediment systems contaminated with a mixture of three polycyclic aromatic hydrocarbons

This study investigated the degradation patterns in sediments contaminated by a defined mixture of polycyclic aromatic hydrocarbons. Particular focus was placed on the effect of naphthalene and acenaphthene on the degradation of fluoranthene in slurry systems by a mixed bacterial culture. The culture was obtained from sediment at Dickinson Bayou, Houston, Texas and was enriched on naphthalene as the sole carbon source. When solely present in slurry systems, aqueous phase concentrations of fluoranthene remained constant, but were rapidly reduced when in the presence of either or both naphthalene and acenaphthene. The results indicate cometabolism or fortuitous oxidation as the probable mechanism of degradation in slurry systems contaminated by a mixture of polycyclic aromatic hydrocarbons. Further work is ongoing to elucidate these mechanisms.