Abstract: In a method of purifying contaminated liquids and gases, a continuous surface film (31) is produced by means of a nozzle (15) and is simultaneously irradiated by a suitable radiation source (17), e.g. an UV lamp. The surface film (31) is discharged as a falling or trickling film (33) which is also exposed to the radiation. A gas for purification is passed through the surface film (31). In these conditions the pollution particles and other pollutants in the gas are absorbed by the liquid. The advantage of the process described is that decomposition of the pollutants can take place both in the gas phase and in the liquid phase. Gas pollutants which are not decomposed in the gas phase are absorbed by the liquid, where they are finally decomposed. With the present invention liquids and gases can be treated simultaneously.