Oxidation of polycyclic aromatic hydrocarbons under sulfate-reducing conditions

[¹⁴C]naphthalene and phenanthrene were oxidized to ¹⁴CO₂ without a detectable lag under strict anaerobic conditions in sediments from San Diego Bay, San Diego, Calif., that were heavily contaminated with polycyclic aromatic hydrocarbons (PAHs) but not in less contaminated sediments. Sulfate reduction was necessary for PAH oxidation. These results suggest that the self-purification capacity of PAH-contaminated sulfate-reducing environments may be greater than previously recognized.