6 - Degradation of pharmaceuticals in wastewater

Abstract

The majority of the human pharmaceuticals that have been detected in the natural environment have arisen though their discharge in parent or metabolized forms into sewage wastewater which is then treated to various levels of purification to progressively lower the concentrations of pharmaceuticals before discharge of effluent into an aquatic environment. This chapter will introduce a range of physical, biological, and chemical remediation techniques that are the basis of three key wastewater treatment steps—primary, secondary, and tertiary sewage treatment processes. Examples are given of different types of specific processes such as primary sedimentation, secondary biological oxidation, tertiary membrane filtration, and advanced oxidation processes. These are illustrated with the results of both field and laboratory studies of these wastewater treatment processes applied to the degradation and removal of some common pharmaceuticals including paracetamol, diclofenac, ibuprofen, β-blockers, oseltamivir, and fluoxetine. Finally, the effect of the natural organic matrix present in all wastewater on pharmaceutical removal and degradation is briefly considered.