Emphasizing the importance to monitor pesticides and their degradation products and/or metabolites from several vegetables. Typically for this type of analysis, ultra-high-performance liquid chromatography coupled to mass spectrometry and gas chromatography coupled to mass spectrometry (GC-Q-Orbitrap-MS) are used. The dissipation of the active ingredients and their degradants should be monitored at multiple doses (I.e., normal, and double dose) from a prolonged period, like 1 to 40 days (about 1 and a half months) after the application of the commercial product. The Half-lives (DT50) of the products must be determined to figure out the persistence of the compounds in the vegetables. Not only the original pesticides have to be monitored but also the metabolites of the compounds must be considered because in some cases these can be more dangerous for human health than the parent compounds. Mass Analytica is supplying tools for Quantification and calculation of kinetic parameters, to monitor the known compound and to search and elucidate the structures of potential metabolites or degradants.