A method, using a photocatalyst, to accelerate the reduction of semivolatile organic chemicals absorbed into porous, solid materials. The porous, solid material having absorbed one or more semivolatile organic contaminants. The photocatalytic material located on the surface of the porous, solid material is exposed to a light source, under aerobic conditions, which excites the photocatalyst and results in the reduction of the absorbed semivolatile organic chemical contaminants.