Polycyclic Aromatic Hydrocarbons (PAHs) are known for their adverse and cumulative
effects at low concentration. In particular, the PAHs accumulate in sewage sludge
during wastewater treatment, and may thereafter contaminate agricultural soils by
spreading sludge on land. Therefore, sludge treatment processes constitute the unique
opportunity of PAH removal before their release in the environment. In this study,
the ability of aerobic microorganisms to degrade light and heavy PAHs was investigated
in continuous bioreactors treating trace-level PAH-contaminated sludge.