IVL has performed a follow-up study on anti-inflammatory and analgesic drugs on commission fromthe Swedish EPA. In the first project was sewage water and sludge investigated. This investigation wasfocused on the occurrence of these drugs in surface water, sediment and fish in a watercourseinfluenced by the local WWTP. For this purpose was an analytical method developed capable toconcentrate, separate and detect free and conjugated anti-inflammatory drugs.Eight pharmaceutical drugs were analysed: paracetamol, acetyl salicylic acid, salicylic acid, ibuprofen,naproxen, ketoprofen, diclofenac and two metabolites of ibuprofen.Conjugated anti-inflammatory drugs were detected at low concentrations (< 1 % of total) in influentand effluent. In the water and sediment samples were all the analysed drugs detected but at somewhatdifferent pattern than in the sewage water. The anti-inflammatory drugs and paracetamol were notdetected in fish collected in the vicinity of the WWTP discharge point.