Natural solid-gas interfaces, such as soil and vegetation, can accumulate globally relevant pollutants such as the Persistent Organic Pollutants (POPs) and chemicals coming from chemical spills or resulting from applications with a specific purpose. Surfaces are, in most cases, the first contaminated environmental compartment and from which the generalized spread of organic pollutants takes place. A particular case is that of pesticide applications. They are needed on the surfaces during a certain period of time, to actuate, but after this they are unwanted compounds and their residues should be removed. Photo-degradation is recognized to be one of the major dissipation pathways of pesticides on solid surfaces under natural conditions [1]. We studied the photo-transformation of vinclozoline on the model surfaces silica and cellulose in the presence of additive that can increase the photo-degradation pathway under sunlight irradiation- citrate ammoniacal iron (III). The main photoproducts were obtained (figure 1) for vinclozoline with addition of [2C6H5O7FeIII · C6H6O7(NH4)2 ·nH2O]. Vinclozoline give one major product in silica and cellulose – 3,5 dichlorphenyl isocyanat and this is main product in phototransformation with and without addition of citrate ammoniacal iron (III) . Main product can be easy transformed in 3,5- dichloroaniline under influence of water or UV irradiation. With addition of [2C6H5O7FeIII · C6H6O7(NH4)2 ·nH2O] we can observe essential acceleration (comparative to the model without additives) of degradation of vinclozoline on solid support . After carrying out investigation on liquid and solid state we can say that phototransformation pathway with addition of citrate ammoniacal iron (III) is equal to pathway in natural conditions (on silica and cellulose).figureFigure 1 : GS-MS traces of vinclozolin on silica 30 min UV irradiated (254 nm) without (2) and with addition of ammonium ferric citrate (1)