During the course of this book, we have witnessed how wastewater represents an important agronomic resource especially in areas of the world affected by drought or where availability is usually limited. However, this practice raises many fears not only in the environmental field but especially in the case of food safety. In fact, wastewater represents the main source of diffusion of pharmaceutical residues (including degradation products and metabolites) in the aquatic and terrestrial environment. For assessing the occurrence of drugs and related substances, sensitive analytical methods have recently become available.