The water-insoluble gaseous pollutants NOx (NO and NO2) and toluene were subjected to UV-C254+185 nm irradiation in humid air, and their photodegradation was quantitatively studied. The pollutants were efficiently decomposed by the ozone and OH radicals produced by UV-C254+185 (nm) irradiation. Because the decomposition products were water soluble, they could be removed with an air washer, which was used for post-treatment. When the photoreactor was dip-coated with a TiO2 catalyst, the photodegradation of the pollutants was enhanced. We propose that the coupling of UV-C254+185 nm irradiation and an air washer would be a useful system for the removal of gaseous pollutants. (c) 2006 Elsevier B.V. All rights reserved.