Microbial Degradation of Aromatic Hydrocarbons in Marine Sediments

摘要

This study examined how adsorption to marine sediments affects thebioavailability of aromatic hydrocarbons. Sediment slurries were used to study microbial mineralization of the aromatic hydrocarbons, phenanthrene and naphthalene, added at low concentrations. Two types of experiments were performed, abiotic extraction assays and biotic mineralization assays (bioassay). In abiotic experiments, both phenanthrene and naphthalene became more resistant to chemical extraction with time and increasing organic carbon content. In bioassays, the percent phenanthrene or naphthalene mineralized decreased with increasing sediment concentration and in general with increasing organic carbon content of the sediment. However, the organic carbon content of the sediments did not entirely explain the differences seen in mineralization of these aromatic hydrocarbons. The organic carbon content of the sediment appears to strongly control adsorption of these aromatic hydrocarbons and, therefore, their bioavailability generally decreased in the presence of sediment, especially in sediments with high organic carbon compounds, it is predicted that if spills occur in Lower Cook Inlet, these compounds are likely to persist for decades.