Analysis of pharmaceuticals in wastewater and removal using a membrane bioreactor

13 pages, 5 tables, 3 figures, 1 appendix.-- PMID: 17115140 [PubMed].-- PMCID: PMC1805043.-- Published online Nov 18, 2006.

Much attention has recently been devoted to the life and behaviour of pharmaceuticals in the water cycle. In this study the behaviour of several pharmaceutical products in different therapeutic categories (analgesics and antiinflammatory drugs, lipid regulators, antibiotics, etc.) was monitored during treatment of wastewater in a laboratoryscale membrane bioreactor (MBR). The results were compared with removal in a conventional activated-sludge (CAS) process in a wastewater-treatment facility. The performance of an MBR was monitored for approximately two months to investigate the long-term operational stability of the system and possible effects of solids retention time on the efficiency of removal of target compounds. Pharmaceuticals were, in general, removed to a greater extent by the MBR integrated system than during the CAS process. For most of the compounds investigated the performance of MBR treatment was better (removal rates >80%) and effluent concentrations of, e.g., diclofenac, ketoprofen, ranitidine, gemfibrozil, bezafibrate, pravastatin, and ofloxacin were steadier than for the conventional system. Occasionally removal efficiency was very similar, and high, for both treatments (e.g. for ibuprofen, naproxen, acetaminophen, paroxetine, and hydrochlorothiazide). The antiepileptic drug carbamazepine was the most persistent pharmaceutical and it passed through both the MBR and CAS systems untransformed. Because there was no washout of biomass from the reactor, high-quality effluent in terms of chemical oxygen demand (COD), ammonium content (N-NH4), total suspended solids (TSS), and total organic carbon (TOC) was obtained.

The study was supported financially by the European Union EMCO project (INCO-CT-2004-509188) and by the Spanish Ministry of Education and Science project EVITA (CTM2004-06255-CO3-01-A) and by the project CTM2005-24254-E. J.R. gratefully acknowledges the I3P Program (Itinerario integrado de inserción profesional), co-financed by CSIC (Consejo Superior de Investigaciones Científicas) and European Social Funds, for a predoctoral grant. Waters (Milford, USA) is gratefully acknowledged for providing the SPE cartridges and Merck (Darmstadt, Germany) for providing the HPLC columns. Hydrochlorothiazide and glibenclamide were kindly supplied by Dr M. Ahel (Centre for Marine and Environmental Research, Zagreb, Croatia).

Peer reviewed