Occurrence of Pesticides and Hormones in Municipal Wastewater and their Removal by Membrane Bioreactors

he presence of emerging contaminants (ECs), including pharmaceutically active compounds (PhACs), steroid hormones and pesticides, in municipal wastewater as well as in the aquatic environment has been an issue of concern from an environmental and human health point of view. These ECs have been found in municipal wastewater in the concentration range of several μg/L. Considering the importance assumed by many of ECs, it is not possible to ban their usage. Therefore, it is essential to effectively remove these contaminants to protect the environment and drinking water resources. There is evidence that conventional treatment methods are not able to completely remove many ECs, therefore, advanced processes are demanded in order to degrade these ECs and protect both water environment and human health. Membrane bioreactors (MBRs), coupling biological degradation with membrane filtration, are one possible option due to the advantages that characterize this technology. The present chapter discusses the occurrence and fate of pesticides and hormones in wastewater and proposes a comparison between removal efficiency of conventional activated sludge treatments and MBRs, also defining common concentrations at which these ECs are found in wastewater.