Most conventional wastewater treatment plants hardly remove micropollutants, such as pharmaceuticals. Here the ability of a submerged nanofiltration flat sheet module to remove pharmaceuticals from wastewater is analyzed. The nanofiltration membrane was used at the relatively low pressure of only 0.7 bar; at such low pressure, the membrane does not retain salts to a great extent. This is advantageous in wastewater treatment because no salt concentrate is produced. Carbamazepine was retained only slightly by the nanofiltration membranes, whereas diclofenac was retained by approximately 65%. (C) 2009 Elsevier B.V. All rights reserved.