Activated carbon (AC) is used for the removal of organic compounds from freshwater and saltwater systems. The effect of salinity on the sorption of organic compounds by sorbents with pores such as AC is not yet well understood. Phenanthrene sorption equilibrium and kinetic experiments are performed in the present work. An EPA granular AC bed model is employed to demonstrate the effect the salinity has on the breakthrough curves at different phenanthrene initial concentrations. At high relative to the solubility phenanthrene concentrations (20050 mu g/L), sorption is higher in the saltwater than in the freshwater solutions. At low relative to the solubility phenanthrene concentrations (3 mu g/L), sorption is lower in the saltwater than in the freshwater solutions. Activated carbon is less efficient in removing phenanthrene from saltwater than from freshwater solutions when phenanthrene is present at low relative concentrations (<10 mu g/L).