Upgrading of Wastewater Treatment Plants Through the Use of Unconventional Treatment Technologies: Removal of Lidocaine, Tramadol, Venlafaxine and Their Metabolites

Abstract

The occurrence and removal efficiencies of the pharmaceuticals lidocaine (LDC), tramadol (TRA) and venlafaxine (VEN), and their major active metabolites monoethylglycinexylidide (MEGX), <em>O</em>-desmethyltramadol (ODT) and <em>O</em>-desmethylvenlafaxine (ODV) were studied at four wastewater treatment plants (WWTPs) equipped with activated sludge treatment technologies. In parallel to activated sludge treatment, the removal efficiency of the compounds in pilot- and full-scale projects installed at the WWTPs was investigated. Within these projects two different treatment methods were tested: adsorption onto powdered/granulated activated carbon (PAC/GAC) and ozonation. The metabolite MEGX was not detected in any sample. The concentrations of the target analytes in wastewater effluents resulting from activated sludge treatment ranged from 55 to 183 (LDC), 88 to 416 (TRA), 50 to 245 (ODT), 22 to 176 (VEN) and 77 to 520 ng L⁻¹ (ODV). In the pilot project with subsequent treatment with PAC/GAC, the mean concentrations of the analytes were between