Abstract

The main objective of this book chapter is to determine the fate of antibiotic resistance genes (ARGs) in organic wastes such as sewage sludge (SS) from sewage treatment plants (STPs) in the framework of the circular economy (CE). The performance of ARGs in different processes for treating SS in STPs as aerobic and anaerobic digestion is discussed. Moreover, the risks associated to the reuse of organic wastes in agriculture related to the ARG’s fate are also discussed in this book chapter. The results of this study showed that ARGs can be detected in SS with abundances in the range of 106–1018 copies/g·dry weight (DW). Regarding the potential risks associated to the occurrence of ARGs in SS, the soil amendment may represent a relevant human exposure and, therefore, a potential human health and environmental risk that requires the establishment of safe procedures and legislation for ensuring the safe reuse of SS.