Most countries, especially developed countries have regulations in place to control pesticides usage, but their residues are still detected in raw agricultural commodities and processed foods. The purpose of first and second part was to evaluate validation parameters, matrix effect (ME %), reduction behaviour, processing factor (PF) in contaminated tomato and orange fruits. The third part was focused on the development of photocatalytic degradation of metalaxyl, chlorpyrifos, and diazinon from artificially contaminated tomato puree and orange puree.The results of the first and second parts showed successful trends by evaluating validation parameters [selectivity, linearity, limits of detection (LOD), limits of quantification (LOQ) and precision]. the results of the third part focused on the development of photocatalytic degradation to be a promising method for decontamination of fruits and vegetables with pesticides. We investigate the coupling between Laser irradiation with TiO2nanoparticles catalyst in order to study the photocatalytic degradation of metalaxyl, chlorpyrifos, and Diazinon.