LC-HRMS determination of anti-cancer drugs as occupational contaminants applied to photocatalytic degradation of molecules of different stability

The occurrence of toxic drug residues is a hot topic concerning emerging environmental contaminants. The occupational exposure to anticancer drugs could be severe for health-care personnel and general public attending potentially polluted areas (such as oncology departments of hospitals) because of high therapeutic concentrations. The aim of this work was to generate degradation compounds similar to those formed in metabolic or environmental pathways by adopting a photocatalytic process and to identify them in indoor environments alongside parent compounds. A photodegradation model was applied to cyclophosphamide and mitomycin C. Studied substances and degradants were quantified in environmental samples by liquid chromatography with multiple-stage mass spectrometry (LC–MSn) analysis using an orbital trap instrument with an electrospray interface. Various oxidative degradants were formed using the photocatalytic simulation model of degradation of antineoplastic drugs, beside some hydrolysis and molecule breakdown subproducts. High resolution MSn spectra were used to identify and confirm the proposed structures. Kinetics of formation of the main degradation products were also studied.